U.S. patent application number 10/957896 was filed with the patent office on 2005-06-23 for illuminator with peak wavelength variation.
Invention is credited to Gardiner, Allan, Haber, Constance.
Application Number | 20050135102 10/957896 |
Document ID | / |
Family ID | 38814274 |
Filed Date | 2005-06-23 |
United States Patent
Application |
20050135102 |
Kind Code |
A1 |
Gardiner, Allan ; et
al. |
June 23, 2005 |
Illuminator with peak wavelength variation
Abstract
Illuminators and systems are provided that permit the production
of a beam of electromagnetic radiation having selected peak
wavelength, bandwidth, intensity, pulse frequency and pulse
duration for a variety of analytical and therapeutic applications.
Multiple beam illuminators use filter elements arranged into filter
arrays, having characteristic wavelength absorption properties. By
providing a series of filter arrays formed into tracks having
defined wavelength offsets, radiation passing through a portion of
a track can be modified to include selected peak wavelength and
bandwidth. Selection of peak wavelength(s) and bandwidth can be
accomplished using mechanical interrupters, mechanical shutters, or
electro-optical devices including liquid crystal device. Multiple
output beams permit the coordinated illumination of a target, and
sensors provide feedback regarding the effects of illumination on a
target. Computer storage devices, programs, and controllers can
provide easy selection of the characteristics of the output beams.
Output beams can have a variety of different shapes and
configurations, depending on the desired application.
Inventors: |
Gardiner, Allan;
(Kensington, CA) ; Haber, Constance; (Murrysville,
PA) |
Correspondence
Address: |
FLIESLER MEYER, LLP
FOUR EMBARCADERO CENTER
SUITE 400
SAN FRANCISCO
CA
94111
US
|
Family ID: |
38814274 |
Appl. No.: |
10/957896 |
Filed: |
October 4, 2004 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10957896 |
Oct 4, 2004 |
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10180643 |
Jun 26, 2002 |
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6886964 |
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60301376 |
Jun 26, 2001 |
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60301319 |
Jun 26, 2001 |
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Current U.S.
Class: |
362/276 |
Current CPC
Class: |
G01J 3/10 20130101; G01J
3/02 20130101; A61B 5/389 20210101; G01J 3/0229 20130101; A61B
5/0531 20130101; A61N 5/0619 20130101; A61N 2005/0663 20130101;
G01J 2003/1213 20130101; G01J 3/0232 20130101 |
Class at
Publication: |
362/276 |
International
Class: |
F21V 001/00 |
Claims
1-42. (canceled)
43. An illuminator for providing an output beam of electromagnetic
radiation, comprising: a source of electromagnetic radiation; a
filter array for controlling wavelength; and a controller of peak
wavelength variation.
44. The illuminator of claim 43, wherein said controller is
selected from the group consisting of non-overlapping filters and
shutters.
45. The illuminator of claim 43, wherein said output beam has a
peak wavelength in the range of ultraviolet to infrared
wavelengths.
46. The illuminator of claim 43, further comprising at least one
waveguide comprising an optical fiber.
47. The illuminator of claim 43, wherein said peak wavelength
variation has a waveform selected from linear, sinusoidal and
trapezoidal.
48. The illuminator of claim 43, wherein said source is selected
from the group consisting of incandescent, gas discharge and
radiation emitting diode devices.
49. An illuminator, comprising: a source of electromagnetic
radiation; at least one filter array; means for selecting at least
one of peak wavelength, bandwidth and intensity of said radiation
thereby forming a beam of output radiation; and means for providing
peak wavelength variation.
50. The illuminator of claim 49, wherein said means for providing
peak wavelength variation provides a linear, sinusoidal or
trapezoidal wavelength variation.
51. The illuminator of claim 43, wherein said filter array
comprises at least one concentric circular filter array.
52. The illuminator of claim 43, wherein said wavelength variation
is in the range of about 1 nm to about 100 nm.
53. The illuminator of claim 43, wherein rate of wavelength
variation has; a lower limit of about 1 nm/sec; and an upper limit
of about 100 nm/sec.
54. The illuminator of claim 43, wherein wavelength variation
occurs as a step change.
Description
RELATED APPLICATIONS
[0001] This U.S. Utility Patent Application claims priority to U.S.
Provisional Patent Application, Ser. No. 60/301,376, entitled
"Multiple Wavelength Illuminator," filed Jun. 26, 2001, and U.S.
Provisional Patent Application Ser. No. 60/301,319, entitled
"Therapeutic Methods Using Electromagnetic Radiation," filed Jun.
26, 2001.
[0002] This U.S. Utility Patent Application is related to U.S.
Utility Patent Application Ser. No. ______, entitled "Therapeutic
Methods Using Electromagnetic Radiation," Allan Gardiner and
Constance Haber, inventors, filed Jun. 26, 2002. Each of the above
applications is incorporated herein by reference.
BACKGROUND
[0003] 1. Field of the Invention
[0004] This invention relates to devices used for illumination of
target objects by electromagnetic radiation. In particular, this
invention relates to illumination devices having multiple beams,
each of which can have selected wavelength, bandwidth, pulse
duration, pulse frequency and intensity.
[0005] 2. Description of Related Art
[0006] Physical treatment of disorders associated with the
peripheral nervous system is becoming increasingly important in the
management of disease. Acupuncture, acupressure and related healing
arts typically involve the mechanical stimulation of peripheral
sensory and motor nerves. In acupuncture, needles are typically
inserted through the skin to reach the desired locations.
Acupressure involves the application of localized surface pressure
above the desired site and the transmission of that pressure to the
nerves under the skin.
[0007] Stimulation of peripheral nerves can be accomplished using
heat or infrared radiation. Infrared radiation can be produced
using lasers or sources of incoherent electromagnetic
radiation.
[0008] There is a need in numerous technologies for providing two
or more selectable wavelengths of radiation. Examples include
electromagnetic radiation therapy, fluorescence microscopy,
contrast enhancement for photography or machine vision, and
simulation of radiation combination effect from sources of
radiation having narrow spectral ranges, such as light emitting
diodes ("LEDs"), and characterization of the quality of optical
systems.
[0009] There is also a need in the art for inexpensive devices that
can produce electromagnetic radiation of discrete wavelengths and
deliver beams of those discrete wavelengths separately from one
another.
[0010] A variable bandpass tunable filter system is available
commercially from Ocean Optics, Inc. that consists of two filters,
each coated with a linearly variable multilayer interference
coating, providing a "wedge" filter. To select a bandwidth, two
filters are placed overlapping each other, in series with the
source of radiation, so that a beam of radiation passes through
both filters. To increase the bandwidth of output radiation, the
two filters are offset relative to each other. Although this system
can provide output variable bandwidth, because the output radiation
must pass through both filters, desired wavelengths the output beam
will be reduced in intensity.
[0011] Therefore, there is need in the art for inexpensive
illuminators that can provide output beams of electromagnetic
radiation having controllable wavelength, bandwidth and
intensity.
SUMMARY OF THE INVENTION
[0012] One object of this invention is the production of devices
for illuminating target objects with electromagnetic radiation in
selected wavelengths in the range from ultraviolet to infrared.
[0013] Another object of this invention is the manufacture of
devices that can provide multiple beams of electromagnetic
radiation of controlled wavelength ranges.
[0014] Yet another object of this invention is the manufacture of
devices that can be used to direct separately controlled beams of
electromagnetic radiation to selected target sites.
[0015] A further object of this invention is the manufacture of
devices that can produce electromagnetic radiation having
controllable ranges of wavelengths.
[0016] Yet another object of this invention is the manufacture of
devices that can produce electromagnetic radiation having
controllable bandwidths.
[0017] An additional object of this invention is the production of
systems for therapeutic use of electromagnetic radiation that can
incorporate illuminators for delivery of electromagnetic radiation,
monitoring effects of therapeutic radiation, for coordinating
therapeutic intervention and subject's physiological responses to
therapy, and devices for maintaining information concerning
electromagnetic radiation therapy of individual subjects and groups
of subjects.
[0018] These and other objects are achieved by devices that in
certain aspects, incorporate a generator of non-coherent
electromagnetic radiation ("illumination source"), band pass
filters ("filters"), and wave guides (including optical fibers). An
illumination source can produce a broad range of wavelengths of
electromagnetic radiation, including, but not limited to
ultraviolet, visible and infrared wavelengths. The term
"illumination source" includes embodiments having a single source
of radiation and one or more devices for dividing the radiating
element ("beam splitter"). Desired wavelengths can be selected by
electromagnetic filtering devices which selectively absorb
undesired wavelengths. The radiation passing through the filter can
then be captured by one or more wave guides for transmission to
sites remote from the source. A portion of the radiation produced
by the source may be captured into a focusing device for filtering
and transmission to therapeutic sites. A beam splitter or separate
sources can two or more separate beams of electromagnetic
radiation, which can be separately controlled.
[0019] Selection of a peak wavelength in a beam can be accomplished
by using a plurality of "filter arrays," each array comprising a
plurality of filter elements, each filter element having selected
transmission characteristics. Materials having known transmission
spectra are known in the art. By selecting materials having desired
transmission spectra, one can produce a series of filters having
different transmission characteristics. For some filter materials,
the radiation transmitted through the filter material does not
necessarily represented as a single wavelength, but rather
comprises radiation having multiple wavelengths, all of which
comprise the "bandwidth" of the beam of radiation. Each of these
materials has characteristic maximum transmitted wavelength ("peak
wavelength" or "peak .lambda.") and bandwidth dispersion
("bandwidth"). Bandwidth means the range of wavelengths in a beam
that are either greater than or less than the peak wavelength.
[0020] By way of illustration only, one filter can remove
wavelengths outside the "orange" range, permitting only wavelengths
in the orange visible range to pass. Next to the "orange" filter, a
"yellow" filter may be present that removes wavelengths outside the
yellow region. When the beam of radiation passes through the
"orange" filter, orange radiation is produced, and when the beam
passes through the "yellow" filter, yellow radiation is produced.
By placing the filters in non-overlapping fashion, in parallel with
each other, one portion of the beam passes through the "orange"
filter, and another portion of the beam passes through the "yellow"
filter. After combining the outputs of the two filters, the
resultant radiation has characteristics of both the "orange" and
the "yellow" filters. This arrangement can minimize undesirable
losses of intensity that can occur when an output beam passes
through overlapping filters.
[0021] By providing a plurality of filters, each having different
bandwidth characteristics in an array, and by moving the filters
relative to the source beam, one can control the wavelengths and
the bandwidth dispersion produced by the device. Thus, it can be
desirable to provide an array having a large number of different
filters arranged progressively, with filters having short maximum
transmitted wavelength at one end of the array and filters having
long maximum transmitted wavelengths at another end of the array.
By moving the filters relative to the source beam, or by moving the
source beam relative to the filters, the wavelength of an output
beam can be controlled. In embodiments using linear filters,
movement of the series can be accomplished using linear motors and
the like. A filter array can alternatively be arranged in a circle
or arc on a disk. Angular (rotational) movement of the filter array
relative to an incident beam of radiation can be accomplished using
rotary means, such as a rotary motor. Radial movement can be
accomplished using, for example, a linear motor.
[0022] Controlling the bandwidth of radiation can be accomplished
using series of filter arrays described above. For example, to
produce radiation having a desired mean wavelength (e.g., and
"orange" color) and a narrow bandwidth, a single "orange" filter
can be used. The bandwidth can be determined by the bandwidth
characteristics of the filter medium. To produce radiation having
the same mean "orange" wavelength as above, but having a greater
bandwidth dispersion, one can use a plurality (e.g., two or more)
similar filter arrays, having, for example, "red", "orange" and
"yellow" regions near each other. If the "orange" regions are
adjacent to each other, and a portion of the beam passes through
only the "orange" regions of the filter arrays, the output will be
"orange" and will have a relatively narrow wavelength bandwidth.
However, if the "orange" region of one filter is offset, so as to
be adjacent to the "red" region of one and the "yellow" region of
yet another filter array, then different portions of the source
beam can be directed to pass through each filter. After combining
the three separate output beams into a single beam (e.g., using a
"mixer"), the transmitted radiation comprises all three "colors".
In this case, the maximum transmitted wavelength can be orange, yet
both red and yellow wavelengths can also be present. The previous
discussion is intended only to provide an example of the principle
of operation of the devices of this invention, and is not intended
to be limiting. Numerous other configurations of filters, filters
having certain maximum transmitted wavelengths and bandwidth
dispersion characteristics are possible, and are all included in
this invention. Other configurations include those that can be used
to select wavelength and bandwidth characteristics in the
ultraviolet, red, blue, green, infrared and other, desired regions
of the electromagnetic spectrum.
[0023] In other aspects of this invention, bandwidth can be
controlled by adjusting the dimensions of an aperture that selects
a portion of the output beam containing desired spectra. Thus, with
apertures having dimensions comparable to a single filter element
in a filter array, the transmitted bandwidth will be small. In
contrast, if an aperture is large and encompasses a plurality of
filter elements, the transmitted radiation can have a wider
bandwidth.
[0024] In addition to providing a fixed, single wavelength, the
wavelengths of electromagnetic radiation can be varied during
application. For example, in some embodiments, it can be desirable
to provide "wavelength variations" around a "central wavelength."
In such embodiments, a central wavelength can be selected and the
illuminator can be used to vary the wavelength to include
wavelengths of longer or shorter wavelengths, typically in the
range of about .+-.1 nm to about .+-.100 nm, alternatively about
.+-.5 nm to about .+-.50 nm, in other embodiments in the range of
about .+-.20 nm to about .+-.50 nm. It can be appreciated that
other ranges of wavelength variation can be used. It can also be
appreciated that one can have variations about a central wavelength
that are asymmetrical, that is, the change in wavelength can be
greater in one direction than in the other.
[0025] Similarly, the rate of change of wavelength, from the lowest
to the highest can be in the range of about 1 sec to about 100
sec., alternatively about 5 sec to about 50 sec, in other
embodiments in the range of about 20 sec to about 50 sec.
Additionally, the rate of change of wavelength can be in the range
of about 1 nm/sec to about 100 nm/sec, alternatively in the range
of about 5 nm/sec to about 50 nm/sec, and in other embodiments,
from about 20 nm/sec to about 50 nm/sec.
[0026] Moreover, the rate of change of wavelength can be varied,
and includes by way of example only, linear changes, a sinusoidal
output, whereby the rate of change of wavelength varies according
to a sine wave function, in other embodiments, the change of
wavelength can be trapezoidal. It can be appreciated that any type
of a large number of variations in wavelength about a central
wavelength can be used.
[0027] To create wavelength variations as described above, in
certain embodiments of this invention, a series of filters can be
provided that, when placed in a beam of electromagnetic radiation,
produces an output beam having a spatially arranged series of
different wavelengths (e.g., red at one end and blue at another
end). Thus, by placing interrupters in front of the output beam and
by changing the relative positions of the output beam and the
interrupter, one can select various portions of the output
spectrum. For example, using a linear array of filters having
different wavelengths represented in a two-dimensional array, a
circular interrupter that has a "window" or trasparent region that
encompasses different distances from an axis of rotation (e.g., a
"eccentric aperture") can be used to select different portions of
the filter array and thereby select wavelengths that can vary over
time. It can be appreciated that the input beam can encompass a
relatively large portion of the interrupter window.
[0028] Additional aspects of this invention include the use of
arrays of shutters positioned relative to a filter array so that
radiation passing through each filter element can be blocked by an
individual shutter. Shutters can be controllable either by
mechanical means (e.g., rotating mirrors or plate shutters, or
electrical means (such as liquid crystal devices or other
electro-optical shutters). By selectively opening desired shutters,
radiation passing through a desired part of a filter array can be
captured by a waveguide or series of waveguides. In such fashions
one can provide output beams having desired intensity, desired peak
wavelength and desired bandwidth.
[0029] By directing the output, of such an array, two or more
discrete, separate beams can be provided.
[0030] Waveguides can be flexible, so that the output of the
waveguides can be directed toward desired target locations.
[0031] This invention includes devices that regulate the intensity
of radiation. Such devices can vary the intensity of the source of
radiation, the use of shutters, apertures and the like, and by the
use of interrupters that interrupt the beam for certain periods of
time during a duty cycle.
[0032] One or more "interrupters" or "choppers" can interrupt the
output beam to provide repeated pulses of radiation, the pulses
having desired frequency and each pulse having a desired duration.
Interrupters can also be used to alter the total amount or dose of
radiation delivered. Other electronically operated interrupters or
mirrors may be used to modulate the intensity of the output beam.
Some common types of electronic interrupters include "liquid
crystal devices", or "LCD"s.
[0033] The shape of an output beam can be controlled so as to
produce beams having circular, annular, polygonal, or other desired
shape.
[0034] Additional components of systems of this invention include
computer interface, software and hardware for running programs that
control the output beams and record information obtained from
monitoring sensors. Systems of this invention can also include
memory devices and software that maintain records of treatment
protocols, physiological responses to treatment, efficacy of
therapy, annotations, other information regarding the subject's
therapy and condition, and can include transmission of subject
information to and from remote sites.
[0035] Systems including the illuminators of this invention can be
used to treat acute and chronic pain, and a variety of disorders
involving abnormalities in the function of excitable tissues,
including, but not limited to peripheral somatic nerves, autonomic
nerves, muscles, connective tissues and the central nervous system.
Additional description of therapeutic uses are included in
concurrently filed patent application titled "Therapeutic Methods
Using Electromagnetic Radiation" Constance Haber and Allan
Gardiner, inventors, incorporated herein fully by reference.
BRIEF DESCRIPTION OF THE FIGURES
[0036] This invention will be described according to embodiments
thereof. Other features of the embodiments of this invention are
described in the Figures, in which:
[0037] FIG. 1 depicts a schematic diagram of a system of this
invention for producing electromagnetic radiation.
[0038] FIGS. 2a-2b depict a schematic drawing two views of a
portion of an illuminator of this invention.
[0039] FIGS. 3a-3i depict embodiments of this invention having
rectangular filter arrays.
[0040] FIGS. 4a-4c depict embodiments of this invention having
circular filter arrays.
[0041] FIGS. 5a-5e depict embodiments of this invention having
different mixtures of output from illuminators.
[0042] FIGS. 6a-6g depict common types of end effectors used with
the illuminators of this invention.
[0043] FIG. 7 depicts the use of an illuminator of this invention
to monitor vascular function in a subject's hand.
[0044] FIG. 8 depicts a system for monitoring and analyzing signals
generated to an illuminator of this invention and physiological
signals produced in response to signals generated by the
illuminator.
[0045] FIG. 9 depicts an embodiment of this invention in which
output of two radiation sources is combined into a single output
beam.
[0046] FIG. 10 depicts a portion of an embodiment of this invention
having a rotating mirror to interrupt an output beam.
[0047] FIG. 11 depicts an alternative portion of an embodiment of
this invention having a rotating, multifaceted mirror.
[0048] FIG. 12 depicts a portion of an embodiment of this invention
having a multiple segment mirror.
[0049] FIG. 13 depicts a portion of an embodiment of this invention
having a rotatable mirror and two sources of electromagnetic
radiation.
[0050] FIG. 14 depicts an alternative portion of an embodiment of
this invention having a rotatable mirror and two sources of
electromagnetic radiation.
[0051] FIGS. 15a and 15b depict an embodiment of this invention
having a circular filter array.
[0052] FIGS. 16a-16c depict embodiments of this invention having
apertures that control the peak wavelength and bandwidth of a beam
of radiation passing through a filter array.
[0053] FIG. 17 depicts an embodiment of this invention in which a
shutter array is used to select peak wavelength and bandwidth of an
output beam of electromagnetic radiation.
[0054] FIG. 18 depicts an embodiment of this invention in which a
shutter array is used to select peak wavelength, bandwidth, and
intensity of an output beam of electromagnetic radiation.
[0055] FIG. 19 depicts part of an embodiment of this invention,
comprising an interrupter wheel having regularly spaced transparent
portions to permit light to pass through therethrough. The duty
cycle is fixed.
[0056] FIG. 20 depicts an alternative part of an embodiment of this
invention, in which an interrupter wheel has a transparent portion
to permit a linear change in light intensity.
[0057] FIG. 21 depicts an alternative part of an embodiment of this
invention, in which an interrupter wheel has a transparent portion
to permit both increase and decrease in light intensity passing
through the wheel.
[0058] FIG. 22 depicts an alternative part of an embodiment of this
invention, in which an interrupter wheel has an a circular edge, so
that with rotation, the beam of light can be at least partially
occluded.
[0059] FIG. 23 depicts an alternative part of an embodiment of this
invention, in which an interrupter wheel has an eccentric
transparent portion.
DETAILED DESCRIPTION OF THE INVENTION
[0060] Illuminators of this invention include sources of
electromagnetic radiation (including visible radiation "light")
that incorporate simple, reliable means for producing beams of
radiation having desired wavelengths and/or other characteristics.
A source of broad-band electromagnetic radiation produces radiation
having a wide range of wavelengths, including those desired. One or
more filters placed in the path of the radiation can attenuate
certain wavelengths that are not desired, permitting desired
wavelengths to pass through the filter and directed to a target.
The wavelengths of radiation that pass through the attenuator
("filter") have a characteristic spectrum, depending upon the
properties of the attenuator. It can be desirable to rapidly change
the wavelength, wavelength bandwidth characteristics, polarization,
to provide pulses of radiation, and to direct beams of radiation to
a desired, localized target area. Means are provided to supply
radiation, to attenuate radiation, to direct and shape a beam of
radiation, and provide a pulsatile beam having desired pulse
duration and frequency to suit a particular purpose. Systems are
provided to coordinate the production of one or more beams of
radiation and to direct beams independently of one another. In some
of these embodiments, the characteristics of multiple beams of
electromagnetic radiation can be regulated separately.
[0061] Radiation can be used to treat pathophysiological
conditions, such as those caused by diseases or disorders.
Physiological responses to electromagnetic radiation of different
frequencies is variable. For example, ultraviolet radiation of
wavelengths in the range of about 200 nanometers ("nm") to 300 nm
(ultraviolet wavelengths) can be used for sterilizing wounds or
other physical objects, and infrared radiation of wavelengths
longer than 700 nm maybe used to heat tissues. Each wavelength of
the spectrum from 200 nm to about 1000 nm or more can be absorbed
by tissues differently to provide different responses. Simultaneous
application of two or more wavelengths can be used to augment the
response that would have been effected by application of a single
wavelength. Because of the variability of each subject (animals and
human), the ability to select specific wavelengths for that
individual is desirable. Additionally, varying the wavelength
during treatment can augment therapeutic effects.
[0062] A Illuminator Radiation Sources
[0063] Illuminators of this invention are not dependent upon any
particular radiation source for operation. Each type of source
(e.g. tungsten, tungsten-halogen, arc, gas discharge, broad
spectrum radiation emitting devices "LEDs", and the like) has a
spectral output that may be useful for various applications. In
certain emdodiments, incandescent lamps can provide desirable
ranges of wavelengths, can be found in a variety of configurations,
can be inexpensive and readily available. In other embodiments, for
example, arc lamps provide radiation containing wavelengths from
ultraviolet through infrared that can be used as a radiation source
that can be used to deliver beams of electromagnetic radiation
having a narrow bandwidth that can be selected over a wide range of
peak wavelengths. Another series of embodiments include gas
discharge lamps that can supply radiation pulses having high power.
Some lamps, such as commercial tungsten-halogen reflector lamps are
pre-focused such that it can be possible to reduce the number of
lenses are required in the optical radiation path to provide a beam
having desired dimensions.
[0064] B Filter Based Selection of Wavelength and Bandwidth
Characteristics
[0065] Certain embodiments of this invention include means for
controlling the output of electromagnetic radiation arising from a
lamp. In several embodiments of this invention, the means for
controlling the output comprises an attenuator, dichroic filter or
series of attenuators or dichroic filters. As used herein, the term
"dichroic" means a filter or attenuator that passes certain
wavelengths of radiation based upon the wavelength of that
radiation.
[0066] A plurality of filters can be used to adjust the bandwidth
of the output radiation beam. In certain embodiments, a filter
assembly comprises a series of individual filter elements, each
having a transmission maximum at a certain wavelength. This
wavelength is termed the "peak", "central", or "mode" wavelength.
Additionally, each filter element has a certain range of
wavelengths that can pass through in sufficient amount to be useful
for the intended purpose of the illuminator. The wavelengths that
can pass through a filter element is termed the "bandwidth" or
"wavelength range". For certain filter elements, the bandwidth can
be relatively narrow, that is, the peak wavelength and only a
relatively narrow range of wavelengths on either side of the peak
can pass through in significant amounts. In contrast, for other
filter elements, the intrinsic absorptivity of the filter material
is such that a relatively wide range of wavelengths can pass
through in significant amounts. Such filters are herein termed
"wide bandwidth" filters.
[0067] Many types of filters are available, and any type of filter
material can be used that is compatible with the types of
electromagnetic radiation, the other components of the system, and
the ultimate use of the illuminators. For example, plastic, glass,
quartz, resin or gel filters can be provided in sizes that can be
adapted for use in a variety of configurations. In certain
embodiments, filter elements can be made of a base material and
then provided ("doped") with a material suitable for controlling
the radiation emitted from the illuminator. In other embodiments,
coated glass can be used.
[0068] Once manufactured, a plurality of filter elements can be
arranged in an array. For example, a series of filters can be
arranged linearly, to provide a series of filters having
progressively increasing (or decreasing) peak transmission
wavelengths. Alternatively, a linear array of filters can be
provided in which certain peak wavelengths are clustered, that is,
not necessarily in progressively increasing (or decreasing) peak
transmission. In certain other embodiments, filter elements can be
arranged in a circular or ovoid fashion on a rotating disk. Thus,
when the disk rotates and/or translates relative to a radiation
source, the bandwidth characteristics of the radiation can be
selected. Alternative embodiments of this invention utilize a
series of fixed filters which allows selection of spectral
transmission based upon the location of the filter assembly
relative to the beam of radiation passing through. Alternatively, a
single filter can be manufactured that has bandwidth
characteristics controlled by way of example, an externally applied
electrical field.
[0069] Regulation of the peak wavelength can be readily
accomplished using dichroic filters. Filters having selected peak
wavelength bandpass characteristics are known in the art, and can
be obtained, for example from Ocean Optics, Inc. Filters can be
made using precision lithography, such as used in the semiconductor
manufacturing industry.
[0070] The "bandwidth" of a filter assembly is the range of
frequencies (wavelengths) that pass through a filter. A band pass
filter has a transmission that is high for a particular band of
frequencies and with a lower transmission of frequencies above and
below this band. The width or narrowness of the band for
frequencies transmitted through a filter is often measured by the
"half bandwidth" that is the full width of the band at half-power
or half of the peak transmittance points specified in either
wavelength units or in percent of center wavelength. Another common
measure of a bandwidth filter is the "half-power point" that is the
wavelength at which a filter is transmitting one-half of its peak
transmission power. For example, for a bandwidth filter with a peak
transmission of 80 percent, the wavelengths at which it transmits
40 percent are the half-power points.
[0071] Color is an attribute of visual experience that can be
described as having quantitatively specifiable dimensions of hue,
saturation, and brightness or lightness. The visual experience also
can include other aspects of perception, including extent (e.g.
size, shape, texture, and the like) and duration (e.g. movement,
flicker, pulse duration, and the like). Color names (e.g. blue,
turquoise, etc.) are often used to describe various wavelengths or
groups wavelengths of visible light. The radiation used in
scientific, industrial, and medical instruments is generally
specified by the wavelengths transmitted and the proportions of
each wavelength within the active area. The use of color names can
be a convenient way to express the appearance of the light. For
purposes of these descriptions, color names can be used to convey
an approximate range of wavelengths used. Color names often
describe combinations of wavelengths of radiation from differing
portions of the visible spectrum. The color to wavelength
conversion identity varies slightly from the various resources. One
source, Van Nostrand's Scientific Encyclopedia, Third Edition,
lists the conversion as:
1 Violet 390-455 nm Blue 455-492 nm Green 492-577 nm Yellow 577-597
nm Orange 597-622 nm Red 622-770 nm
[0072] However, other reference books recite other wavelength
ranges for the above colors. Thus, we do not intend that each color
name be provided with an exact wavelength or bandwidth
characteristic. Rather, each of the colors described herein is
intended to be a guide for use of the devices of this invention.
For example, for therapeutic purposes, the color "violet" may
contain amounts of longer, blue wavelengths, and may also include
certain amounts of shorter wavelengths, in the ultraviolet range.
Similarly, the color yellow may contain certain amounts of green
and/or orange light. Moreover, other colors described by their
common names may include greater or lesser amounts of other,
wavelengths.
[0073] Some commonly named colors include two or more wavelength
bands of light. Magenta, for example, has two peaks, one in the
violet region and another in the red region. Purple has peaks
similar in wavelength to Magenta but has higher violet
transmission.
[0074] Perception of a given color may result from combinations of
wavelengths added together. The most common combination is
red+green+blue. These three colors are used in differing
proportions in computer monitors and displays to create the colors
available on the display. Other combinations of filters may be used
in parallel to produce perceived color. The printing industry
adapts to varying ink properties as a routine matter.
[0075] 1. Filters
[0076] When used for therapeutic purposes, a purpose of filtering
radiation to specific narrow bandwidth characteristics is to
provide radiation having wavelengths that interact with particular
biologic components (e.g. nerves, muscles, blood vessels, blood,
etc), specific chemicals or molecules, or other wavelength-specific
receptors. By selecting the desired wavelength(s) and the
bandwidths of wavelengths can permit a rapid and efficient means of
delivering a reproducible electromagnetic stimulus to an area or
volume of tissue or other material.
[0077] In certain embodiments, our invention utilizes filters that
transmit a single wavelength or narrow bandwidth of wavelengths.
One aspect of our filter design permits control of the width of the
bandwidth by means of moving the filter in two directions with
respect to the radiation path. Movement of the filter relative to
the radiation source in one direction controls the peak, center,
mean or mode wavelength, and movement in another direction can
provide radiation having differing bandwidth ranges.
[0078] In certain embodiments, a fixed aperture that limits the
transmission of radiation to a well-defined area such that the mix
of wavelengths transmitted represents the sum of filter elements
within that aperture. The amount of radiation at the peak
transmission wavelength may diminish as additional filter elements
of differing wavelengths are introduced into the radiation path.
This design is simple and can use any desired aperture area
practical. Movement of the filter during treatment allows a
continuously variable peak wavelength, providing a "wavelength
variation," which can be varied in magnitude (e.g., how much the
wavelength changes around a central wavelength), intensity, pattern
of wavelength change and speed of wavelength change.
[0079] 2. Linear Filter Arrays
[0080] In certain embodiments, a series of filters having different
fixed transmission characteristics may be placed between a
radiation source and one of the waveguides. These filters may be
used to select the desired ranged of wavelengths or to exclude
large segments of the spectrum, such as, for example, infrared
blocking filters.
[0081] In other embodiments of this invention, a linear filter,
such as a Schott Veril 60, may be manufactured such that the
transmission spectrum continuously changes with respect to the
position along the filter array. The variable spectrum
characteristics of the filter array are accessed as desired by
moving the filter array along the variable wavelength axis through
the radiation beam in the illuminator section by means of a
mechanism. The mechanism must allow repeatable motion when driven
manually or by a motor. One embodiment of this apparatus uses a
leadscrew and carriage assembly to move the filter. A linear
version of the circular variable filter described below may be
manufactured as either an array of individual filters or as an
array that permits changes in the width of the spectrum and maximum
transmitted wavelength by moving the filter array in two axes
transverse to the radiation beam.
[0082] It other embodiments, "wedge" type filters can be used, in
which an absorptive medium is provided on a substrate. One portion
of the wedge typically has a thinner layer of absorptive medium,
and another portion typically has a thicker layer of absorptive
medium. An interference pattern can be generated by wavelengths of
radiation, so that radiation transmitted can have different
wavelengths, depending upon the thickness of the layer of
absorptive material. Certain filters useful for the devices of this
invention can be obtained commercially from Ocean Optics, Inc.
Thus, in certain embodiments, two or more wedge filters can be
place near one another so that the radiation emitted by both
filters can be collected and used. However, the above description
is not intended to be limiting, rather any available filter types
can be used.
[0083] In certain embodiments, arrays of small filter elements can
be provided that have small size (about 1 .mu.m on a side) and
manufactured using photolithographic methods, as used in the
semiconductor manufacturing industry. For radiation having short
wavelengths, (e.g., 200 nm), the size of the filter elements can be
even smaller (e.g., 200 nm). Planar arrays of such filters can have
large numbers of individually manufactured filters, and, if
desired, each can have different bandpass characteristics. Certain
of these types of filter arrays can be obtained from Ocean Optics,
Inc.
[0084] Filters may be fixed in place or moved into or out of the
beam by mechanisms provided for that purpose. The characteristics
of the filters are selected for the requirement of the system. For
example, a filter may pass two or more fixed wavelengths of
radiation through one illumination section which is then combined
with a variable wavelength radiation from another illumination
section to provide more specific narrow wavelengths than the number
of illumination sections. Additional filters may be selected or
automatically placed in the radiation path as designed into the
particular mechanism. Some example of the filter types are narrow
band, cut-off, or bandwidth filters.
[0085] The variable filter used to select the wavelength or
spectrum of wavelengths for each illumination section may be
created by a variety of methods and physical shapes and sizes. The
filter media maybe of any type that has the desired radiation
transmission characteristics. Some example filters include gel
filters, interference filters, dichroic filters, substrate filters
or other types known in the art. The geometry of the illumination
beam and the shape and position of filters can be adjusted to
obtain radiation having desired spectral characteristics.
[0086] 3. Circular Filter Arrays
[0087] In certain embodiments, a circular filter array can be used
that has a pattern of filter elements or materials that allow
transmission of different wavelengths at different rotational
positions around the circular filter array. The filter array may be
rotated to discrete angular positions manually or motorized for
remote control. A means of repeatedly returning to a desired
angular position can be provided by a dial or by a memory element
associated with the motorizing system. Some examples of a
motorizing system are a stepping motor with a means of initializing
the angular position, or, a servo motor with an encoder which
provides initializing information.
[0088] The dimensions of the beam of radiation relative to the
active circumference of the illumination section can contribute to
the spectral distribution of the radiation entering the waveguide.
In some embodiments, a variable filter pattern can comprise an
annulus that has variable wavelength transmission along the
circumference that passes through the illumination path as the
filter is rotated about its axis of rotation. One result can be
that each angular position corresponds to a different specific
narrow spectrum of wavelengths. For filter arrays having continuous
and monotonically changing transmission along the circumference of
the array, the width of the radiation spectrum emerging from the
illumination section is determined by the ratio of the active
circumference to the diameter, or width (for non-circular entrance
ports) of the beam entering the waveguide. A filter array may also
be manufactured that comprises a series of discrete filter elements
or materials which are accessed by rotation of the filter disk.
[0089] In certain embodiments, a process permits manufacturing of a
pattern such that the transmission characteristics of any angular
and radial position can be selected. The pattern may be such that
the area of each pattern element is small relative to the active
area of the beam. This allows the center of rotation of the
circular filter to be moved relative to the beam to provide
differing transmission characteristics based on both active radius
and angular position. For example, the outer radius portion of the
pattern area may have a constant linear variability, for example,
from 400 nanometers ("nm") to 1000 nm, that provides a narrow
spectrum of wavelengths to emerge from the illumination section,
while the inner portion of the pattern area may provide a mixture
of elements that combine to provide a broader spectrum of
wavelengths to emerge from the illumination section. Thus moving
the center of rotation and angle of the filter relative to the
radiation beam can select a specific narrow wavelength or a wider
spectrum of wavelengths. This ability to select center wavelength
and spread of wavelengths allows the system to provide additional
control over the radiation emerging from the illumination
section.
[0090] Illuminators of this invention may have a fixed aperture
that limits the transmission of radiation to a well-defined area
such that the mix of wavelengths represents the sum of filter
elements within that aperture. The amount of radiation at the peak
transmission wavelength may diminish as additional filter elements
of differing wavelengths are introduced into the radiation path.
This design is simple and can use the maximum aperture area
practical. In other embodiments, an aperture having variable area
may be constructed that may increase in size if desired to allow
additional radiation of differing wavelengths to be added to the
original beam. Conversely, if it is desired to provide a narrower
band pass, the aperture can be decreased in size to exclude
undesired wavelengths from passing. This design can be used to keep
the amount of radiation at peak transmission wavelengths
approximately constant while adding radiation of differing
wavelengths.
[0091] In other embodiments, selection of peak wavelength,
bandwidth and/or intensity can be controlled by the use of a
plurality of shutters positioned relative to a filter array. By
opening certain shutters that are positioned corresponding to a
desired peak wavelength, a beam of radiation can be captured that
has that selected peak wavelength. In other embodiments, one can
open up shutters corresponding to higher, lower, or both higher and
lower wavelengths to permit the passage of radiation having a
broader bandwidth. In yet other embodiments, one can open up a
plurality of shutters corresponding to a peak wavelength to
increase the intensity of radiation in an output beam. In still
further embodiments, a plurality of peak wavelengths can be
selected to provide multiple wavelength output beams. It can be
readily appreciated that numerous variations of the above can be
used to provide a large number of possible output beams.
[0092] The types of shutter mechanisms used are not crucial. In
certain embodiments, one can use mechanical shutters that can be
retracted to open up an aperture. In other embodiments, an array of
mirrors can be used to reflect the beam of radiation toward a
particular location. In still other embodiments, a shutter array
can incorporate an electro-optical device, including by way of
example only, liquid crystal devices (LCDs), Pockels cells, Kerr
cells and other optical devices. In a shutter array, control over
individual shutters can be accomplished using mechanical or
electrical signals, and those can, in certain embodiments, be
controlled by a computer program.
[0093] C Pulsed Illuminators
[0094] In addition to providing radiation having controlled
wavelength and bandwidth characteristics, the radiation may be
provided in a continuous or pulsed fashion. Pulsing radiation can
either provide a frequency of radiation that can be absorbed by
different targets differently to achieve a desired degree of
stimulation, or alternatively as a means for controlling the total
dose of radiation emitted by the device. To provide pulses of
radiation, any suitable mechanism that can regulate the pulse width
(duration), the frequency, or the pattern of radiation pulses can
be used. For example, in several embodiments, radiation can be
passed through a shutter or interrupter system to provide the
aforementioned radiation as pulses at variable frequencies. In a
circular interrupter, a disk of opaque material having holes,
slits, slots, or areas of transparency can be rotated about an axis
perpendicular to the plane of the disk. A portion of the rotating
disk can be placed in a beam of radiation, and during the time that
a hole or transparent area is in front of the beam, the beam can
pass through the disk, thereby providing the desired radiation.
When an opaque portion of the disk is in front of the beam, the
radiation is blocked from passing through. Advantages of pulsed
radiation include increased efficacy of electromagnetic radiation
therapy. For example, the use of different frequencies of radiation
pulses has been demonstrated to affect nerve cells differently from
muscle cells. The selection of the wavelength and frequency of the
radiation can be based upon methods developed for each
application.
[0095] An interrupter or shutter mechanism may be placed in the
radiation path of an illumination section to provide intermittent
pulses. An interrupter can be desirable if it transmits all of the
radiation in the open state. The number of apertures in the
interrupter and the rotational speed of the interrupter can
determine the pulse rate. Low pulse rates may also be obtained by
oscillating the interrupter aperture across the radiation beam. The
rate that the interrupter is moved may be varied over time to
produce a profile of radiation intensity vs. time. A single
interrupter may be placed such that two or more radiation sources
pass through the interrupter. The placement of the radiation
sources, the placement of the center of rotation of the
interrupter, and the number of apertures affect the relative timing
of the pulses for each radiation source. Certain of these
embodiments can have four apertures and two radiation sources
placed symmetrically around the center of rotation such that the
initiation of each pulse is concurrent for both entrance ports.
Electro-optical shutters, including by way of example only, LCDs,
may be used in place of the interrupter wheel to achieve similar
results and add independent initiation of pulses and/or pulse
profiling.
[0096] It can be readily appreciated that an interrupter or an
electro-optical mechanism can be designed to provide any desired
pattern of pulses. For example, in one series of embodiments, a
circular disk having transparent areas arranged in arcs around the
disk can be used in situations in which it is desired to have a
repeated pattern of pulses. It can be appreciated that the arc
length of a transparent area and the rotation speed can determine
the duration and frequency of pulses. However, by providing
transparent areas of differing configurations, for example, one
having a relatively long arc length, and another having a
relatively shorter arc length, a pattern of long and short pulses
can be provided. It can also be appreciated that providing
transparent areas that are equidistantly arrayed about the disk can
provide a pulse frequency that is substantially constant. However,
by providing transparent areas of differing distances from one
another, one can select the pattern of radiation pulses. By
altering the speed of interrupter rotation, the pulse rate can be
varied.
[0097] During treatment of physiological of pathophysiological
conditions, the oscillating interrupter can provide variable pulse
width, variable frequency, and can be used to vary the wavelength.
The configuration of transparent areas in an interrupter and the
rotational speed of the interrupter can be adjusted to provide a
wide variety of waveforms (see below).
[0098] It can also be appreciated that a pulse can have an abrupt
onset or a ramped onset. By providing transparent areas that have a
clean, or "sharp" edge, the onset of a pulse can be abrupt.
However, by providing a wedge-shaped slot, or alternatively, a
gradient transition between opaque and transparent areas, the onset
of the pulse can be varied. Moreover, in these embodiments, one can
appreciate that providing a slower rotation can provide a prolonged
transition period between "off" and "on" parts of the duty cycle
and can provide longer durations of a pulse. Although different
pulse patterns are described for mechanical interrupters, it can be
readily appreciated that electro-optical interrupters can be used
that can provide a wide variety of pulse patterns.
[0099] In certain embodiments, a sensor may be added to monitor the
beginning of radiation pulses and functionality of the illumination
section. Many devices and methods are available to determine the
start time of a pulse. For example, a fiberoptic pickoff may be
mounted next to the waveguide entrance port. The output of this
pickoff may be used to monitor the wavelength and intensity of the
radiation passing through the illumination section when coupled to
appropriate sensors. The output may be passed through a narrow-pass
filter to initialize a reference position or confirm the positional
repeatability of the system. Another example is a sensor to
determine the location of the interrupter apertures relative to the
entrance ports. Pulse rate can be adjusted by the interrupter motor
controller circuitry based on output of an encoder integral with
the interrupter motor. The accuracy of the radiation pulse rate can
depend upon the control circuitry and may have different ranges of
acceptable accuracy for different applications.
[0100] In one series of embodiments of devices include a radiation
source, filters and an optical system to deliver the filtered
radiation to a waveguide, such as a fiberoptic element. Multiple
radiation sources can be combined in the fiberoptic cable system
and delivered to one or more radiation delivery ports. The routing
of fibers determines the proportion of each wavelength at each
delivery port.
[0101] D Multiple Beam Illuminators
[0102] Devices of this invention can utilize two or more radiation
sources that may be of the same or different types. Typical
radiation sources include incandescent lamps, arc lamps, and strobe
lamps for systems that are intended to provide selectable
wavelengths. Narrow spectrum devices, such as lasers or LED's, may
also be used when the bandwidth dispersion is desirably narrow. Gas
discharge lamps can have several wavelengths that are emitted which
may also be useful, such as combining UV radiation with visible
and/or infrared radiation.
[0103] A radiation source optical system may be as simple as a
mirrored reflector behind the radiation source which can focus the
radiation beam onto the waveguide. Additional optics may be
incorporated as desired for the particular illumination system. For
example, a broad area source, such as a strobe, may use a
collecting or collimating lens system between the source and the
filter. The characteristics of the radiation source reflector may
affect the operation of the system. For example, a reflector may be
used which allows a high proportion of the infrared (heat) emitted
by the radiation source to be transmitted away from the filter and
waveguide.
[0104] E Waveguide/Fiber-Optic Cable Assembly
[0105] In certain embodiments of this invention, a waveguide or
fiberoptic cable assembly can consist of multiple entry ports and
one or more exit ports. Routing of the fibers can determine the
proportion of radiation from each entry port to each exit port. The
material of the waveguides or optical fibers is selected to permit
passage of the desired wavelengths. For example, glass fibers may
be used for visible and infrared radiation (400-1000 nm) while
other materials, such as quartz fibers may be selected for
ultraviolet radiation (200-400 nm). Many configurations and
materials, including liquids, are possible. In certain embodiments,
there can be two entrance ports and two exit ports. The fibers can
be routed to provide one-half of the radiation from each entrance
port to be directed to each exit port. This arrangement can provide
the user with two radiation sources with similar multi-wavelength
output.
[0106] In other embodiments, alternate fiber routing configurations
maybe used to provide different ratios of input to output. For
example, a third entrance port may have a radiation source that
does not utilize a filter system. This illumination section may
provide output from a simple lamp to provide general illumination
or may provide a source of ultraviolet radiation (or infrared, or
other wavelength) that can pass directly into the entrance port of
the waveguide with little attenuation. In other embodiments, a
laser can be used to provide a narrow bandpass light source.
[0107] The output beam of electromagnetic radiation can be provided
in a number of different desired shapes and configurations. For
example, for certain therapeutic uses, it can be desirable to
provide beams having rectangular, triangular, polygonal, circular,
oblong, annular, or other desired shape. By arranging waveguides in
any of the above configurations, a desired beam can be provided. By
providing flexible waveguides, the different beams can be
separately directed at different desired locations.
[0108] F Uses of Illuminators
[0109] The industrial utilization of this device includes many
fields in addition to health care and treatment of disorders. The
ability to control dominant wavelength and bandwidth width is, by
way of example only, can be used for: (a) discriminating subtle
variations in color characteristics for machine vision; (b) grading
of material characteristics automatically, such as fruit ripeness,
or paint reflectance; (c) microscope illumination for biological
and industrial applications, fluorescence microscope; (d) as a
catalyst in radiation triggered chemical processes; (e) simulation
of radiation source and filter combinations; (f) testing of optical
assemblies; and (g) dispersion characteristics of materials,
especially optical materials and fiberoptics, (h) phototherapy
using drugs tha require specific waveforms for activation. Certain
of these uses are described more fully in the U.S. Patent
Application titled "Therapeutic Methods Using Electromagnetic
Radiation" Constance Haber and Allan Gardiner, Inventors, Attorney
Docket No: WMAG 1010 US1 SRM/DBB, filed concurrently and
incorporated herein fully by reference.
[0110] G Analysis of Temporal Data and Therapeutic Responses
[0111] Analysis of spectral and timing data from illuminators of
this invention can be performed using a computer and a software
package, either designed specifically for the purpose, or using
commercially available software. A data filter in a commercial
application including joint time frequency analysis using Fast
Fourier Transform "FFT" as well as other deconvolution methods can
permit correlation of spectral and time related data (pulse or
chop) and physiological effects of electromagnetic radiation. In
certain embodiments, measurements involve monitoring a radiation
signal using the interrupter or electro-optical shutter to expose a
part of a subject's body to radiation of a known wavelength,
wavelength variation, bandwidth, pulse width, intensity, and pulse
frequency. Simultaneously or at intervals, one can monitor effects
of such radiation using, for example, the surface electromyogram
(sEMG or SEMG), electroencephalogram (EEG), evoked responses and
the like. An analog input can be provided into the computer, and
the phase and frequency domain of the signal relative to output of
interrupter signal can be determined using, for example LabView.TM.
software. This can be used to determine the signal strength and the
transit time for the signal to travel to the sensor. In addition, a
system from Neurometrix can be used. The system consists of an
interrupter, which can be run at a frequency of about 1 Hertz (Hz)
to about 1000 Hz. In alternative embodiments, the interrupter can
operate at a frequency of between about 1 Hz and about 500 Hz, and
in still other embodiments from about 5 Hz to about 100 Hz. Using
pulsed illumination a system can detect the presence of signal and
the phase differences between remote locations on the body. This
can permit comparison of transmission capability through excitable
tissues, such as nerves, muscles, and connective tissues, in
conditions such as, for example, diabetic neuropathy and other
nervous disorders, especially disorders of the spine. Normal
physiological responses can be obtained by studying subjects
without specific disorders, or by studying unaffected organ and
tissues of normal subjects.
[0112] Additionally, by comparing the above-obtained normal results
with those obtained from subjects having specific disorders of
excitable tissues and organs, improved diagnosis of those
conditions can be provided. Additionally, by monitoring a subject's
responses to electromagnetic radiation therapy over time, such as
heart rate variability, SEMG and other real-time measurements,
improved evaluation of the progression and/or treatment of those
disorders can be provided. Additional discussion of specific
disorders of excitable tissues is provided in the U.S. Provisional
Patent Application titled: Therapeutic Methods Using
Electromagnetic Radiation, Constance Haber Stevenson, D.C., and
Allan Gardiner, P.E., inventors, filed concurrently, incorporated
herein fully by reference.
EXAMPLES
[0113] The following of examples are intended to be for
illustration only. Other embodiments of this invention can include
variations of the systems and devices described. All of these other
variations and combinations are considered to be part of this
invention.
Example 1
Optical Illuminator I
[0114] In one embodiment, a device is provided that has two lamps
with focusing reflectors, two rotary filter arrays and one
interrupter wheel with four apertures. Control circuitry receives
signals from the operator that provides (a) the intended brightness
of each lamp, (b) the intended wavelength peak for each
illuminator, (c) the intended wavelength spread for each
illuminator, and (d) the intended frequency of output pulses,
wavelength variation. The signals are processed and the appropriate
actions are initiated by servo controllers. The signals from the
operator may be locally developed through electronic and mechanical
input devices or from a remote source such as a computer. The lamps
in this embodiment are standard lamps used for 8 mm movie
projectors. Lamp reflectors concentrate the radiation into a spot
suitable for fiberoptic illumination. The filter is a pattern on a
glass substrate that transmits radiation of varying wavelength
depending upon its angular and radial position relative to the
radiation beam. The filter is produced using a photolithographic
method that allows individual areas of a few square microns to be
individually manufactured with specific filtering characteristics.
Further descriptions are provided with reference to FIGS. 1-18.
[0115] FIG. 1 depicts an embodiment 100 of this invention as
described immediately above. Computer interface 104, receives input
signals from an operator and provides outputs to lamp brightness
control 108, which controls the current or voltage 112 to lamps 114
and 116. The brightness control can be any of a number of different
types, including but not limited to a transistor control or a
transformer with a radiation dimmer. Any means of adjusting the
brightness of the lamps under computer control or manual control
can provide illuminator beams having differing brightness.
[0116] Computer interface 104 provides signals to wavelength driver
120 and bandwidth driver 130 drives the motors 124 and 128 which
position filter arrays (not shown) in series with lamps 114 and 116
to provide output beams 132 and 136 having desired peak wavelengths
and wavelength bandwidth characteristics. The controls of driver
120 can be stepper motors or servomotors, or alternatively
servomotors with closed loop encoders. A desirable feature is the
ability to position filter arrays using motors 124 and 128
reproducibly to the same location relative to the lamps 114 and 116
such that the wavelength of beams 132 and 136 can be controlled
from the host program through the computer interface 104. The
wavelength driver 120 electronics can be a simple system using
transistors or some of the micro controller chips, which provide
position information, acceleration and deceleration. Motion
controls are available commercially from vendors in a variety of
industries to position radiation controlling devices. In the case
of circular filter, the motor may be a direct drive to position the
angle of the filter. In the case of linear filters then the motors
maybe connected to some other devices such as a lead screw or a
rack and pinion system. A second motor is used to position the
filter to control the bandwidth.
[0117] Computer interface 104 provides a signal to interrupter
speed and position control 140, which regulates the position of
interrupter servomotor 144. Interrupter 152 is a simple plate with
slots in it or other holes 204. Interrupter 152 can be a glass disk
with an emulsion that is opaque over part of the area with another
part being clear. A simple embodiment includes a disk with slots in
it with one, two, four or however many slots are appropriate in
order to get the total speed range necessary to get the pulse rate
required for the output. The limiting speed of the motor 144 is
controlled by the interrupter speed position feedback controller
148 or by its own electronics. Servomotor 144 has an encoder which
provides information to the controller 140 of how fast the motor is
turning and the current position of the aperture(s) relative to the
illuminator beam. A reference mark is used to initialize the
location of interrupter 152 attached to servomotor 144 and can
provide information about the timing of the pulse of radiation
emitted by lamps 114 and 116. In this case the home position or
reference mark could be used to know where the radiation is being
transmitted through the interrupter 152. A computer program can
control the interrupter speed position control to move the
interrupter until the reference mark is located. At that point the
counters can be zeroed or that mark in some other way tracked such
that the location of the disk now can be reliably returned to that
open position. Alternatively, or if that speed of the interrupter
is tracked alone and not position then each time is desired to
control the interrupter to be either opened or closed, the
reference mark would be relocated.
[0118] The interrupter speed position controller 140 can be as
simple as a voltage placed out to the motor which would cause the
motor to turn at a desired speed. The control of that speed may not
be as accurate as desired and in that case, a tachometer (not
shown) can be used, and a servo amplifier that controls velocity
could be implemented. Alternatively, a microprocessor can control
the speed and also track the position of the interrupter 152 such
that it would always come to rest in either an opened or closed
position as desired by the operator. Using such a system, it can be
desirable to monitor the output of the illuminator(s) directly, and
not operate solely by presetting desired values of the variables.
The beam may be interrupted by an electro optical shutter or
mirror.
[0119] Wavelength sensors 160 and 164 can be used to monitor the
wavelength of radiation of either one or both illuminators. For
each lamp/filter assembly, one sensor is shown, although two or
more sensors may be used if desired. Each sensor 160 and 164 is
associated with a narrow bandwidth filter, having bandwidths in the
range of a few nanometers. Computer software 156 in the hardware
would be used to find a peak value of wavelength. For instance, if
the wavelength drivers 120 position filter 124 and 128 to a desired
wavelength and the interrupter 152 is positioned so that the
radiation is being transmitted, then the wavelength sensor 160 can
determine whether the desired wavelength is detected. If the
observed wavelength is not as desired, then the computer interface
104 can provide signals to driver controller 120 to adjust the
position of filters 124 and 128 to produce the desired wavelength
of output beams 132 and 136. Combinations of peak bandpass and
bandwidth settings may be used to calibrate the system.
[0120] The system described can allow for ongoing calibration and
confirmation that the wavelength, wavelength bandwidth and other
variables remain as desired. Combinations of peak bandpass and
bandwidth settings may be used to calibrate the system. In
alternative embodiments, one can provide multiple sensors sensitive
to different portions of the filter array. That way the system
could drive the filter to wavelength number one, find the peak,
find the calibrated location that matches wavelength number one,
and then repeat the process for wavelength number two. All of the
intervening wavelengths could be determined by calculation relative
to those two calibration points.
[0121] The first time that the system is used, it can be calibrated
using another device to interpolate the positions in between two
calibration points. And then later, the relative positions of
wavelengths can be used to confirm that the computer now has
confirmed control over wavelength. Additionally, the speed of the
interrupter could be measured by moving the filter to one of the
wavelengths and using the feedback to the computer to determine
that the frequency of the interrupter indeed matches the expected
frequency being programmed by the computer interface. In the
machine design it can be desirable to allow the machine to
self-test upon start up or at any time there is some question about
the accuracy of the system. By providing feedback, the system can
do this self-calibration. A sensor which is sensitive to a wide
range of wavelengths maybe used during operations to detect the
presence of radiation for timing purposes.
[0122] FIG. 2a depicts a schematic diagram of the interrupter
speed/position controller 140 as depicted in FIG. 1. Interrupter
speed position control 140 is attached to the servomotor 144.
Encoder feedback 148 can provide the system with more speed range
and stability of speed. The interrupter disk 152 has two slots 204
shown.
[0123] FIG. 2b depicts a side view of the interrupter 152 as shown
in FIG. 2a. Interrupter 152 is depicted on a shaft of servomotor
144. The disk of interrupter 152 is shown in the path of
electromagnetic radiation produced by lamp 114. Output of lamp 114
is controlled by the output of power controller 112, and is focused
by lens 216 and heat-absorbing filter 212, which maintains the
output beam receiver 224 at a desired temperature. The beam passes
through slots 204 of interrupter disk 152 and the output passes to
filter 220. The output beam then passes through the aperture 230 to
waveguide 224 for transmission remotely to the desired site of
illumination. Relative placement of the heat absorbing filter 212
and the lens 216 can depend on the configuration of lamp 208 and
waveguide 224. In certain embodiments, lens 216 and heat filter 212
may not be required at all. The elements can be placed in other
relationships, depending on the desired configuration. For example,
in certain embodiments, the beam may pass through a filter and then
the interrupter. In other embodiments, more than one waveguide may
be used, in which radiation gathered after passing through an
interrupter can be transmitted remotely to a filter, and then pass
through a filter. If desired, another waveguide can then gather the
filtered radiation for transmission to a remote site for
illumination.
Example 2
Rectangular Filter Array
[0124] FIGS. 3a-3h depict the relationships between lamps, filters
and waveguides of embodiments of this invention having rectangular
filter arrays. FIG. 3a depicts a side view of an embodiment of this
invention with no restricting aperture, including lamp 208, filter
array 220 and waveguide 224. FIG. 3b depicts an embodiment 300 of a
parallel filter array of this invention having two axes. The
vertical dimension of filter array 300 comprises filter elements
arrayed according to peak wavelength, from 400 nm on the top to
1000 nm on the bottom of filter 300. The left side of filter 300
has areas of narrow bandwidth, in which the individual filter
elements have narrow bandwidth characteristics. Toward the right
side of filter 300, the bandwidth of the filter is increased, so
that radiation passing through those areas has a wider bandwidth
characteristic.
[0125] Thus, to provide radiation having a desired peak wavelength
and a narrow bandwidth range, a source beam 224 is aligned with a
portion of the filter 300 on the left side, where the bandwidth is
narrow. Then, by moving the source beam 224 vertically, one can
select the peak wavelength desired. FIG. 3c depicts schematically a
portion 304 of a filter of this invention having narrow bandwidth
range. By moving the filter relative to the source beam 224
vertically in this diagram, the wavelength can be selected. One can
readily appreciate that the bandwidth characteristics of this type
of embodiment can be selected by providing source beam 224 having
dimensions that are greater than the size of an individual filter
element. Thus, in embodiments in which source beam 224 passes
through several filter elements, each having a different peak
wavelength, then the output beam can have a series of wavelengths
corresponding to those wavelengths of the filter elements so
provided.
[0126] FIG. 3d depicts in more detail, an embodiment 300 of this
invention having a rectangular parallel array of filter elements.
As depicted in FIG. 3b, rectangular filter 300 has a vertical axis
having individual filter elements arranged in order of increasing
peak wavelength, from top to bottom, from 400 nm to 1000 nm. The
horizontal axis has a left portion A in which the wavelength
bandwidth is constant at any particular vertical position in the
filter. A relatively narrow bandwidth 320 of portion A is depicted
below portion A. To the right of portion A, portion B is provided
that has a broader bandwidth than that of portion A. An
intermediate bandwidth 324 of portion B is depicted below portion
B. Similarly, portions C and D are provided that have progressively
greater bandwidths, such as depicted by spectrum 328. Thus, by
moving the different portions of filter 300 across a source beam
horizontally, different bandpass characteristics can be
provided.
[0127] FIG. 3e schematically depicts an embodiment of this
invention illustrating rectangular filters which can provide
selectable wavelength bandwidth characteristics for a beam of
electromagnetic radiation. In this embodiment, the wavelength
bandwidth is selected by positioning a source beam relative to one
of a series of different tracks, here labeled 1, 2 and 3, each of
which comprises vertical filter arrays comprising elements having
narrow bandwidth characteristics. In a first area 1, for any
vertical position, the peak wavelength is uniform across the
horizontal direction, and is represented by a horizontal line. An
adjacent vertical filter array 2 is comprised of 3 identical filter
arrays 2a, 2b and 2c. Each of the individual filter arrays are as
depicted for area 1 except that the peak wavelength in area 2a is
offset or displaced to shorter wavelengths by a fixed amount, by
way of example, only, 10 nanometers in wavelength, and area 2c is
offset by a similar amount but to the longer wavelengths. Area 2b
is identically arranged as area 1. Area 3 is otherwise identical to
areas 1 and 2, but comprises 5 discrete vertical filter arrays, 3a,
3b, 3c, 3d, and 3e, with arrays 3a, 3b, 3d, and 3e offset with
respect to area 3c.
[0128] For example, as illustrated in FIGS. 3f, 3g and 3h, the peak
wavelength is shown as 600 nanometers for three different
bandwidths. In FIG. 3f, a single vertical array is present having a
narrow bandwidth, and producing a relatively sharp peak in
intensity of radiation (I) at 600 nm. In FIG. 3g, three vertical
arrays of filters are represented as 3ga, 3gb and 3gc. Vertical
array 3gb is in the same position as the array shown in FIG. 3f,
whereas array 3ga is offset to smaller wavelengths, and 3gc is
offset to longer wavelengths. Thus, radiation passing through area
3ga has a peak wavelength of 590 nanometers and that passing
through area 3gc has a peak wavelength of 610 nm. If an aperture
for a source beam is sufficiently large to encompass areas 3ga,
3gb, and 3gc, then the radiation passing through the filter will
comprise one portion derived from area 3ga, one portion from area
3gb, and one portion from area 3gc, and therefore having a broader
bandwidth than that obtained for FIG. 3f.
[0129] FIG. 3h depicts a series of areas 3ha-3he of vertical filter
arrays of this invention. As with FIG. 3g, radiation passing
through all 5 areas with have a peak wavelength of 600 nm, but with
a bandwidth greater than that of FIG. 3g.
[0130] FIG. 3i illustrates an embodiment 308 of a variable
bandwidth mechanism of this invention. Three filter arrays 309, 310
and 311 each have a peak wavelength of 600 nm. Filter arrays 309,
310 and 311 are depicted being moveable relative to each other by
motors 312, 313 and 314. In FIG. 3i, filter array 309 is depicted
having a peak wavelength of 600 nm in a relatively central position
relative to arrays 310 and 311. In contrast, array 310 is offset by
motor 313 below array 309, and array 311 is offset above element
310 and 309.
[0131] It can be appreciated that other configurations are possible
and can comprise multiple different areas. It can also be
appreciated that the offset of individual areas not need be the
same, so that in certain desired wavelength regions, the bandwidth
can be larger or smaller than the bandwidth in other wavelength
regions. It can also be appreciated that by adjusting the aperture
size, more or fewer regions of each area can be placed in the path
of the source beam and can produce radiation having different
wavelength compositions.
[0132] As the filter is moved in front of the aperture or waveguide
bundle, the amount of radiation for each wave length could be
controlled by moving the filter in the vertical direction to
control the central or peak wavelength and in the horizontal
direction to control the bandwidth spread. By designing the widths
of the vertical filter arrays and their offsets, the ability to
control the wavelength spread can be programmed into the controller
so that the host program can send controls to position different
filter areas, apertures or sources of the beam to provide a high
degree of control over the composition of the radiation emitted by
the illuminator.
[0133] It can also be appreciated that an aperture or waveguide
bundle can be asymmetrical, having, for example a rectangular
cross-section. Thus, if the same bundle were rotated 90 degrees,
for example, then the wavelength spread could be varied.
[0134] By way of illustration for a linear filter, if the distance
between the area having a peak wavelength of 400 nanometers to that
having 1000 nm were six inches long, there would be 100 nanometers
per inch. If the diameter of the source beam were a quarter of an
inch (0.25"), source beam would have approximately 25 nanometers
spread in the wavelengths. For a rectangular source beam, the
intensities of the wavelengths within the spread of 25 nanometers
would be different from the intensities with a circular aperture.
However, for a curved (e.g., circular or ovoid) source beam, the
distribution of wavelengths would be different. The distribution of
a circular beam source would be much more centrally weighted than
for a rectangular source beam. It can be appreciated that if the
admitting aperture or waveguide were a narrow rectangle across the
filter area, then the wavelength spread would be much narrower.
Example 3
Circular Filter Arrays
[0135] FIGS. 4a-4c depict an alternative embodiment of this
invention 408 comprising a circular filter array. In FIG. 4a,
individual filter elements are arrayed circumferentially about the
central axis of the filter 408. At a given distance d from the
central axis, an array of individual filter elements is provided in
a fashion similar to those shown in FIGS. 3b and 3c, but rather
than being linear, they are circular. Thus, by providing source
beam 224 at distance d from the central axis, a particular series
of filter elements can be exposed to the beam. By rotating the
filter 408 about its axis, the wavelength of the radiation can be
adjusted, in this case, between 400 nm and 1000 nm.
[0136] FIG. 4b depicts an embodiment of this invention in which
different regions of filter 408 have different bandwidth
characteristics. In this embodiment, an area more central to the
axis d1 has relatively larger bandwidth characteristics than a more
peripheral area d2. Thus, if a relatively narrow bandwidth is
desired, source 224 can be positioned more peripherally on filter
408, and if a relatively narrower bandwidth is desired, source 224
can be positioned more centrally on filter 408.
[0137] FIG. 4c depicts additional details of a circular embodiment
408 of a filter of this invention, as shown in FIG. 4a and 4b
above. As with FIG. 3e above, there are areas of filter 408 defined
by a distance from the axis r. In area 404, the bandwidth is
relatively narrow and is constant with r. However, in areas 406,
412 and 416, respectively, the bandwidth increases progressively as
distance r decreases, in a fashion similar to that of FIG.
3e-3h.
[0138] The selection of wavelengths for a given position or angle
in a rotary filter may also be selected to be a very different
wavelength characteristics if the combined output of the optical
system requires wavelengths that are of significant differences in
the spread. Tracks A, B, C and D can be varied in other ways also.
For instance, by way of illustration only, track A could have a
peak wavelength of 700 nanometers, track B could be set to have a
peak at 500 nanometers. The combined beam can have a combined
wavelength spread that is much larger than simply a single
wavelength with its usual distribution. The multiple wavelengths
achieved in this way can provide colors which are not available as
pure colors when perceived by the human eye. The same effect of
multiple colors can also be achieved by having an illumination
source set at one wavelength and another set to a different
wavelength so that the combined output of the two and now go and
mimic any color. Embodiments incorporating this strategy can be
expanded to include 3 colors providing red, green and blue, or even
more different wavelengths.
[0139] One advantage of circular embodiments is that controlling
the position can be simpler than controlling a two-dimensional
array as for the embodiments depicted in FIG. 3. In circular
embodiments, the angular position can be controlled by direct drive
on a motor, and then angular position can control the peak
wavelength. The wavelength spread can be controlled by moving the
center of rotation of the disk relative to the radiation path in
the radial direction. In the case of the rotary filter the tracks
are again designed such that the relative placement of the optical
path can select either a narrow spread or a wider wavelength
spread. Circular embodiments can have an added feature of a longer
filter path, depending on the circumference of the disk rather as
simply a linear device. Other advantages of circular embodiments
include the possibility that the size of the total assembly can be
smaller than rectangular arrays because the filter can be
positioned angularly and translated in one axis only. The position
of the source beam can be changed by a simple mechanism controlled
by a stepping motor or servomotor to move the beam radially with
respect to the center of the disk. These motors can be controlled
by the computer interface as depicted in FIG. 1.
[0140] There are a variety of manufacturing techniques which can
produce filters suitable for the illuminators of this invention
where there are tracks or areas which have different wavelength
characteristics. In embodiments having fixed filter elements,
individual elements can be deposited on plastic, glass, quartz or
other substrate in areas which can be addressed as X, Y coordinates
for rectangular arrays as in FIG. 3, or as angle .theta. and radius
r from an axis of rotation for circular arrays as depicted in FIG.
4c. In certain embodiments, the output radiation can have a
graduation of wavelength and wavelength spread. In other
embodiments, changes in wavelength can be more rapid, or even in a
step-wise or saltatory fashion. In certain embodiments, the filter
can move while the waveguide and lamp assembly are stationary, and
in alternative embodiments, the source beam can move and the filter
array can remain stationary. Additionally, if desired, a
rectangular aperture or other non-circular aperture can be used
along with a mechanism which can rotate the aperture relative to
the vertical filter arrays, and in that way even a wider variety of
wavelength spreads could be available from the system. Moreover,
because the embodiments described herein can be controlled by
external signals, each configuration can be programmable and the
composition of the radiation emitted by the illuminators can be
repeatable.
[0141] In other embodiments, an array of liquid crystal shutters
can be positioned over a filter array. By selectively opening one
or more shutters, radiation can be selected. Embodiments of this
type can be especially useful in situations in which it is
desirable to have devices with a minimum number of moving parts, or
in situations in which rapid electrical control over emitted
wavelengths is desired.
Example 4
Waveguides and Output Beams
[0142] Once an output beam is created having certain wavelength,
wavelength bandwidth, pulse duration and pulse pattern, the output
can be directed to a desired location using waveguides. For
example, waveguides can be in the form of a fiber optic cable as
depicted in FIGS. 5a-5e. FIG. 5a depicts a simple, single waveguide
500 having an input end 501 and an output end 502. FIG. 5b depicts
an alternative embodiment of this invention 504 in which a single
input beam 501 is split into two output beams 502a and 502b. FIG.
5c depicts an embodiment of this invention 508 having a dual mixer
cable where some portion of each input beam 501a and 501b goes to
each of the two end effectors 503a and 503b. The ratio for the
output maybe any desired value, for example, from about 1%: about
99% to about 50%: about 50%, or alternatively about 99%: about 1%.
There is no limitation in proportion as long is there is some
portion of each lamp source being mixed in the alternate
output.
[0143] FIG. 5d depicts an embodiment 512 in which three inputs
501a, 501b, and 501c are mixed to provide two outputs 505 and 506.
As with FIG. 5b above, the ratio of the components of the output
beam mixture can vary from about 1%: about 99% to about 99%: about
1%. FIG. 5e depicts another embodiment of this invention 516 where
three inputs 501a, 501b, and 501c are directed to one or more of
the outputs 517 and/or 518. In this embodiment, inputs 501a and
501b are directed to outputs 507 and 508, whereas input 501c is
directed only toward output 508. This type of configuration permits
additional wavelengths to be mixed (a "mixer").
[0144] In certain embodiments, fiber optic cables can be desirable
because fibers from one illuminator port may be directed to the
other fiber optic cable. For applications that do not require fiber
optic cables, the beam from the source and filter can be
transmitted via an optical path which could include mirrors and
beam splitters to combine radiation from multiple lamps. In other
embodiments, fiber bundles having mixed fiber types can be used to
transmit radiation having differing wavelengths. For example, to
transmit both visible radiation and ultraviolet radiation, one can
use plastic or glass fibers to transmit the visible wavelengths,
and can use quartz to transmit the ultraviolet wavelengths.
Example 5
Configurations of Output Beams
[0145] Once an output beam has been produced, the beam can be
delivered to a site using any of a number of different end
effectors. FIGS. 6a-6g depicts a variety of end effectors 600.
Common types of end effectors are available from fiber optic light
source manufacturers. FIGS. 6a1-6a3 depict embodiment 604 having a
source 601 and a "dental end" with a 45-degree bend (FIGS. 6a1 and
6a2), or alternatively a 90-degree bend (FIG. 6a3), or a bend at
any desired angle. These can be simple light pipes made with fiber
optics, which can be relatively resilient and can direct the
radiation at a convenient angle. These can be made to be
replaceable and/or reusable after sterilization, such as in an
autoclave. Dental ends can be obtained from one or more commercial
sources.
[0146] FIGS. 6b1 and 6b2 depict an embodiment 608 of this invention
comprising an input beam 601 and an annular or ring light 602. Such
"ring lights" can be commercially available and can distribute a
bundle of receiving fibers by means of a mechanical housing or
assembly to output light from an annulus "ring" of fibers.
[0147] FIGS. 6c1 and 6c2 depict an alternative embodiment 612 of
this invention comprising an input beam 601 and a series of fibers
distributed to form a "line" 603, or to form a rectangle or other
shape that is desired.
[0148] FIG. 6d depicts an embodiment of this invention 616 that
comprises an input beam 601 an output beam 605 and a lens 606 to
focus the output beam. In an alternative embodiment shown in FIG.
6e, lens 606 can be used to collimate the beam.
[0149] FIG. 6f depicts 4 different shapes of output beams. A square
configuration is depicted by effector end 630, a horizontally
aligned rectangular end 634, a vertically aligned rectangular end
638, anc circular end 642 are shown. However, it can be appreciated
that numerous other shapes of effector ends can be used
advantageously.
[0150] FIG. 6g depicts an embodiment 624 of this invention that
uses two separate input beams 601a and 601b, and two lenses 605a
and 605b to focus two output beams 607a and 607b on a target. It
can be readily appreciated that more than two end effectors may be
used. Input beams 601a and 601b can have the same wavelength
characteristics or can have different characteristics. By providing
different wavelength inputs, a gradient of wavelength intensities
can be generated where the two (or more) output beams interact.
When this device is placed near an object to be illuminated, such a
human finger during therapeutic applications, a gradient of
wavelength interaction throughout a zone within the tissue is
illuminated. One purpose of this gradient is to allow a continuum
of interaction based on relative strength of two or more different
wavelengths. A wavelength gradient can be desirable for treating
conditions where different wavelengths cause different biological
interactions. The ability to combine the two wavelengths in a
graded fashion can permit the illuminated tissues to experience
combinations of stimuli. This can be especially useful when the
precise ratio is not known for maximum therapeutic affect.
Alternative constructions of the applicator can use either line
effectors, ring effectors, rectangular effectors or effectors
having any other desired configuration. Any of the applicators can
be moved relative to one another and across tissue to increase the
area of tissue illuminated.
[0151] In certain applications, an effector configuration can use
two line outputs arranged relative to each other such that the
lines are parallel with overlapping regions of radiation. An
intensity/wavelength gradient can be developed between the lines
along a parallel zone beyond the effectors to increase the volume
of the tissue exposed to the radiation. The spacing and angle of
the effectors can determine the gradient zone.
[0152] In applications in which an effector configuration uses two
concentric rings, each with a separate source, an
intensity/wavelength gradient can be developed between the rings
beyond the effectors. The spacing of the rings can determine the
gradient zone.
[0153] Any of the applicators may be supplied by dual or mixing
type fiberoptic cable assemblies which can have additional
characteristics such as delivering the same wavelengths or
combination of wavelengths to both effectors. This application may
be used to provide more energy at the selected wavelengths
determined by the fiber optic cable configuration.
[0154] Variations on these applicators may concurrently deliver
energy by means of dental effectors, for instance, to the inside
and the outside of the mouth. A mechanical housing can align the
sources so that they remain in alignment while the applicator is
moved. This method can provide the maximum amount of illumination
to the full thickness of the side of the mouth. Use of single
cables can permit uses in which one wavelength is directed inside
the mouth and a different wavelength is directed outside the mouth,
if desired. Use of a mixing cable can provide the same or similar
wavelengths on both sides of the affected tissue. This same general
scheme can be extended to have more than two radiation inputs if
multiple wavelengths are desired.
Example 6
Vascular Imaging
[0155] Devices and systems of this invention can be used for
vascular imaging. In certain embodiments of this invention a body
part can be transilluminated. FIG. 7 depicts an embodiment 700 of
this invention used for this purpose. The system comprises a lamp
114, a filter 220, a waveguide 224 an end effector 600 as described
above. A body part, for example, hand 720 is placed on support 724
and radiation passing through hand 720 is detected using camera
728. The end effector 600 hand 720, calibration source 732 and
camera 728 are depicted housed in a radiation-tight box 702, with a
radiation-tight curtain 703. In operation, the hand is place on a
support 724, and there can be additional registration pins or
bumpers (not shown) which can allow the hand to be placed initially
without the person being required to be very precise. The inside of
the cabinet can be illuminated by an additional lamp 705 to provide
visual feedback while positioning the hand. The actual field of
view of the camera determines the size of the image relative to the
total field. The camera signal is processed by a signal processor
732 which can control brightness and contrast, or any other
variable of the video signal desired in order to produce the best
image possible.
[0156] The output of the signal processor goes to display 736, a
recorder (not shown), or other desired instrumentation. In use,
this system can provide scanning through wavelengths typically in
the 600 to 650-nanometer wavelength range to find the wavelengths
that are most strongly absorbed by the particular person's vascular
system. The wavelength can be changed while observing the output of
the camera, either before or after signal processing, in order to
find the particular wavelengths which provides the best contrast
and visibility of the vasculature within the hand. The location
observed on a particular finger or web of the hand can be selected
for vasculature observation. More than one illumination source may
be desirably provided so that more radiation is available for
illumination through the body part.
[0157] The camera gain and offset can be controlled and
standardized using a calibration target 732 which can permit the
system to be returned to the same settings after treatment. By
providing reproducible initial conditions of observation, the hand
can be placed into the machine again and secondary pictures may be
taken. The change in observed blood flow can be used to monitor
treatments which increase or decrease blood perfusion. For
instance, if the feet are placed in cold water or ice water, the
blood flow to the hands may diminish over a period of time. Such
diminishing flow can be observed through the video system.
[0158] In preliminary experiments, tests have been performed using
a wavelength of 625 nanometers. Initial results indicate that there
are substantial variations in absorption between individual people.
This same apparatus can be configured to accept a foot in which
case people with circulation problems of the feet such as people
with diabetic neuropathy can be observed for changes in blood flow
during and/or after treatment. For the feet, certain blood vessels
are located on the bottom of the toes and the apparatus of this
invention can be configured such that the camera is on the bottom
of the foot and the illumination comes down from the top. The
configuration of the illuminator and the camera can permit
transmission of radiation through the tissue for observation by the
camera. Experiments have shown that radiation around 600 to 650
nanometers appears to be strongly absorbed by blood vessels which
provide imaging capability. Radiation of shorter wavelengths tends
to be absorbed more uniformly and thus the contrast measured using
shorter wavelengths can be diminished. Wavelengths longer than
optimum are absorbed less and again contrast can be diminished. The
optimum wavelength is dependent upon the absorption characteristics
of the particular person. Oxygenation of the blood also affects the
wavelengths absorbed. There may be several wavelengths of interest
and this apparatus can provide measurements using more than one
wavelength. In certain embodiments, the apparatus of this invention
can be used to is observe blood vessels at different depths below
the skin.
[0159] A black and white camera with broad low radiation level
spectral sensitivity can be used to allow varying the wavelength
over a wide range ("sweeping") to determine the desired wavelengths
that are best transmitted through bulk tissue and also those that
can be absorbed by the vascular system. Some cameras possess
infrared sensitivity to wavelengths longer than 700 nanometers
and/or have the capability of having a filter removed from the
optical system which allows the detector, such as a CCD array, to
receive the infrared radiation. In this case it can be desirable to
use the infrared portion of the radiation spectrum rather than the
visible portion because different features within the finger, hand
or toe can be studied using different wavelengths. The ability to
select a wavelength and have sufficiently intense radiation pass
through substantial thicknesses of the body can permit observations
that cannot made with normal full spectrum radiation.
[0160] The repeatability of this system can be improved by
including means of self-calibrating the system and adjusting for
brightness. These elements are not shown in FIG. 8. One such
element can include an integrating sphere with a standardized
sensor in it. An integrating sphere can be moved into a location to
receive radiation from the end effector or optical train built into
the cabinet. The power or intensity of radiation could then be
adjusted and standardized for each wavelength by removing the hand
or other body part from the radiation path and doing a calibration
based on the particular wavelength. Standardized laboratory
techniques can be used to carry out this calibration. Similarly,
calibrations of the video camera can be accomplished using targets
of known illumination. In certain embodiments, targets can have
areas which are either clear or opaque, or may have steps of
opacity which may be moved in front of the camera to measure the
apparent brightness of the radiation source. The placement of these
accessories and the precision of their motion can be designed to
allow repeatability and accurate calibration of measurements with
the device.
[0161] Larger body parts, such as the thicker parts of the hand or
even the thinner portions of the leg maybe imaged using a very
intense radiation source and a very sensitive camera. Thus,
measuring and/or imaging is not restricted solely to thin body
tissues such as fingers or toes. Finer detail is generally seen
with the thinner body parts because the vasculature that is being
imaged is close to the surface. The optical density of the tissue
and its ability to transmit or conduct radiation at varying
wavelengths is dependent on the individual. Individuals with very
fine vasculature throughout the hand, for instance, can appear very
opaque compared to people who have large veins and tissue which
readily conducts certain wavelengths of radiation, such as 625
nanometers. One can also use embodiments of this invention to
transilluminate a body part at one wavelength and then observe that
body part at a different wavelength. Using the systems and
measurement methods of this invention can permit detecting certain
responses of the vascular system to therapeutic intervention.
Example 7
Integrated System for Controlling Illuminator Function
[0162] For many applications, it is desirable to provide software
and a computer with a reference signal to which information coming
back from sensors placed on the skin can be compared to the desired
output beam. An embodiment 800 of such a system for controlling
illuminator function is depicted in FIG. 8. FIG. 8 depicts lamp
114, interrupter motor 144, and the interrupter disk 152, which
interrupts the beam of radiation going through filter 220, and
entering fiber optic cable 224. The fiber optic cable 224 can be
any of the types described herein. The end effector 600 can also be
of any type. To make comparisons of output radiation and the
desired response, an aspect of this system is the ability to
interrupt the output signal at a known frequency and/or divert a
portion of that signal to the computer for analysis. A portion of
the signal can be detected by a pick-off 607. Fiber optic signal
pick-off 607 and detection electronics 608, can condition the
signal for entry into the computer interface 603. Other means of
detecting the signal are possible such as discrete pick-off from
the fiber optic cable itself or from monitoring the position of the
interrupter and computing the beginning and ending of the radiation
going down the fiber optic cable. The position of illumination
apertures 204 may be determined by an encoder instead of a
pick-off.
[0163] One desirable feature of the system, whether the pick-off is
achieved by software or by hardware, can include providing the
software in the computer with a reference signal by which
information coming back from sensors placed on the target (e.g.,
skin) at selected sites can be compared to the reference output
signal generated by the illuminator and captured by the signal
pick-off 607. For therapeutic uses, detectors 601a, 601b and 601c
can be sEMG detectors, thermal sensors, muscle probe detectors, or
any other type of biological or physiological sensor. The signal
from the sensors 601a, 601b and 601c passes through amplifier
assembly 602 comprising an amplifier, isolator and optionally,
filters which are designed to augment the signal of interest which
will be compared to a reference signal. The amplifier filter
assembly 602 can be commercially obtained from a variety of
vendors.
[0164] One purpose of the amplifier assembly is to allow a human
subject to have sensors placed on them without the risk of
electrical signals from the computer interface from causing harm to
the subject. It can be desirable that the amplifier assembly be
able to pass signals having frequencies up to around 600 Hz and
optionally, it maybe desirable to provide a filter for reducing
ambient noise, by way of illustration only, 50/60 Hz noise.
Alternatively, one can provide filters to reduce any signal that is
not desired, by way of example only, EEG signals, EMG signals, and
the like, thereby permitting one to more easily detect and analyze
signals that represent a desired response. Alternatively, this
filtration may take place later using software-configured filters.
The output of the amplifier isolator 602 maybe an analog signal
going to an analog interface and then to the computer 603, or it
may be converted to digital signals and then routed to the computer
603. The software and the computer 604, can desirably perform
analyses of the signals, including joint time and frequency
analysis, or other types of analyses. It can be desirable to place
the sensors at locations where the maximum physiological effects
are to be observed. For example, for monitoring therapeutics of
nerves, it can be desirable to place sensors at locations of
maximum innervation of the muscle of interest. Alternatively, to
monitor muscle activity, sEMG electrodes can be desirably placed
near the muscle to be studied and treated. Multiple sensors can be
used to determine the amount of signal which is coming through at
various points on the body.
[0165] Placement of the illuminator's end effectors can be selected
to provide signals from the output radiation beam into the nervous
system of the individual being studied. The software desirably can
permit the operator to determine the percentage of signal that is
arriving at the various sensors, and thus, maybe an indication of
therapeutic effectiveness. The software can use the pulsed input
signal and the frequency of that signal to discriminate information
returning from the sensors which have a phase and time relationship
to the input signal. The system can thus be operated in a fashion
similar to that of a nerve conduction velocity study carried out
using electrical stimulation. However, rather than electrical
stimulation, systems of this invention can use electromagnetic
radiation provided at selected intensities, pulse durations and
pulse frequencies. In those embodiments using a rotating
interrupter, the interrupter's rotational velocity can determine
the pulse frequency. The pulse duration can be selected by
adjusting the size of the interrupter's slit relative to the
circumference and rotational velocity of the interrupter disk. In
embodiments using electrical or other means to provide pulses, the
input can be in the form of control signals to the interrupter.
Different variables, including pulse duration, frequency, and
intensity can be independently controlled.
[0166] The combination of the wavelength, bandwidth, pulse duration
and pulse frequency can affect selected excitable tissues,
depending on intrinsic-responsiveness of those tissues to the
radiation. The relationships of output signals from tissues to the
input signals can be determined for a variety of different
wavelengths and frequencies. In certain embodiments, these
determinations can be made automatically with the aid of a computer
system that had been pre-programmed for the purpose. The ability to
make measurements at a variety of different wavelengths and
frequencies of intermittent radiation or signal can permit the
adjustment of illuminators to maximize outputs detected by the
sensors. The combination of multiple illumination systems, multiple
end effectors and/or multiple interrupters can permit the
practitioner to more finely select desired variables to optimize
diagnosis and treatment of disorders of excitable tissues, such as
nerves, muscles and connective tissues.
[0167] The illumination system maybe replaced by electronic
emitting device, such as LED, once the selected wavelengths are
known and the ability to scan wavelengths provides the operator
with additional control. The system allows the ability to go and
determine the nerve conduction properties of an individual before
and after treatment in order to determine if nerve conduction has
improved. In one specific application for persons with diabetic
neuropathy of the feet, the detection of nerve conduction may be
used in conjunction with other standard techniques for monitoring
the abilities of the patient such as monofilament testing. The
ability to inject signals and vary both the frequency and the
wavelengths permits the operator/system to determine the optimal
conditions for treating this and other disorders.
[0168] In certain embodiments, optical systems other than
waveguides can be used to transmit the radiation and resize or
reconfigure a radiation beam as required by some other piece of
equipment.
Example 8
Alternative Optical Configuration I
[0169] In certain of these embodiments, mirror beam selectors can
be provided to direct certain portions of emitted radiation. FIG. 9
depicts an alternative embodiment 900 of this invention in which
two beams of radiation are combined into a single output beam.
Lamps 114 and 116 produce electromagnetic radiation that passes
through lenses 216 and 217 and then through filter arrays 220 and
221. The beams of radiation are then reflected by rotatable mirrors
904. A portion of the reflected radiation then is captured by
waveguide 224 for remote transmission to a site of illumination. It
can be appreciated that by rotating the mirrors selectively,
selected portions of the radiation from either source can be
reflected to waveguide 224.
Example 9
Alternative Optical Configuration II
[0170] Another embodiment 1000 is depicted in FIG. 10. Lamp 114
produces a beam of electromagnetic radiation, a portion of which is
reflected from rotatable mirror 904, passes through filter 224 and
is captured by waveguide 224.
Example 10
Alternative Optical Configuration III
[0171] Another embodiment 1100 of this invention is depicted in
FIG. 11. Lamp 114 produces a beam of radiation that is reflected by
multifaceted rotatable mirror 908. A portion of the reflected beam
passes through filter 220 and is then captured by waveguide
224.
Example 11
Alternative Optical Configuration IV
[0172] In another embodiment of this invention 1200 depicted in
FIG. 12. Lamp 114 produces a beam of electromagnetic radiation that
is reflected by a multiple segment mirror 912. Mirror 912 can be,
for example, a DLP.TM. mirror.
Example 12
Alternative Optical Configuration V
[0173] In yet another embodiment of this invention 1300 depicted in
FIG. 13, a beam can be selected from between two different lamps
114 and 116. As rotating mirror 904 rotates, the beams of radiation
arising from the lamps 114 and 116, respectively, can be reflected
alternatively through filter 220 and captured by waveguide 224.
Example 13
Alternative Optical Configuration VI
[0174] In a further embodiment of this invention 1400 depicted in
FIG. 14, lamps 114 and 116 are shown near each other. As rotating
mirror 904 rotates, the beams of radiation produced by lamps 114
and 116, respectively, can be reflected alternatively through
filter 220 and captured by waveguide 224.
Example 14
Selecting Bandwidth Using a Circular Filter
[0175] FIGS. 15a and 15b depict an embodiment 1500 of this
invention in which the bandwidth of a beam of radiation is selected
using a circular filter 408. FIG. 15a depicts circular filter 408
that is rotated by motor 1506 about an axis of rotation x. Filter
408 has area 1504 which has one bandwidth that is at radius r from
axis x.
[0176] FIG. 15b depicts a side view of the embodiment 1500, in
which lamp 114 is shown producing a beam of radiation that passes
through area 1504 of filter 408 and then is captured by waveguide
224. Area 1504 is shown at radius r1 relative to the axis of
rotation x. To change the bandwidth of the beam of radiation
captured by waveguide 224, motor 1506 moves in response to forces
produced by another motor (not shown), which can translate motor
assembly 1506 (arrows) relative to the lamp 114, so that area 1508
(at radius r2) from axis x on filter 408 is now in position
relative to lamp 114, so that the radiation passing through area
1508 can be captured by waveguide 224.
Example 15
Selection of Bandwidth by Variable Aperture
[0177] In certain embodiments of this invention, the bandpass
characteristics can be selected by adjusting an aperture. FIGS.
16a-16c depict such embodiments. FIG. 16a depicts an embodiment
1600 in which aperture 230 overlays a filter array 1601. The peak
wavelength .lambda.p is shown, as is the spectrum of intensity I at
each wavelength .lambda. (insert). The maximum intensity is found
at .lambda.p.
[0178] FIG. 16b depicts an embodiment 1604 in which filter array
1602 has an area of narrow bandwidth filters (left side), and an
area of progressively wider bandwidth filters (right side). The
position of .lambda.p is shown as in FIG. 16a. Aperture 234 is
shown over the narrow bandwidth area of filter 1602, so the
spectrum (insert) shows a maximum wavelength at .lambda.p, as in
FIG. 16a, but the intensity I is less than that for FIG. 16a,
reflecting the decreased area of filter 1602 through which the
output beam passes.
[0179] FIG. 16c depicts an embodiment 1608 in which filter 1602 and
aperture 234 are as shown in FIG. 16b except that aperture 234 is
displaced to the right compared to FIG. 16b. By being displaced
into the area of wider bandwidth, the spectrum of output radiation
(insert) shows a peak at .lambda.p, but also has a wider bandwidth
than depicted in FIG. 16b. In other embodiments, aperture 234 can
be expandable in either the horizontal or the vertical dimension,
or both. For example, by expanding the horizontal dimension of
aperture 234 to the right, one can include broader bandwidths and
keep the intensity of .lambda.p the same. Thus by controlling the
left and/or right sides of aperture 234, one can control the
.lambda.p as well as the bandwidth and the relative intensities of
the different wavelengths transmitted.
Example 16
Selection of Bandwidth by Liquid Crystal Shutters
[0180] FIG. 17 depicts an embodiment 1700 of this invention in
which filter array 1704 has areas of different bandwidth filters
thereon. On the left side of filter array 1704, .lambda.p is shown,
and progressively to the right, areas of progressively wider
bandwidth are present (with .lambda.p shown as horizontal lines).
An array of liquid crystal shutters 1708 is shown in relationship
to filter array 1704. Shutter array 1708 has two dimensions, x and
y, so each shutter element in the two-dimensional shutter array
1708 has a unique x and y coordinate. The horizontal x dimension
has elements addressed by a, b, c, d, e, and so on. The vertical y
dimension has elements addressed by 1, 2, 3, 4, 5 and so on. Each
element can be controlled by a voltage applied to that element, so
that in one voltage state, the liquid crystal of that element is
"open" and radiation can pass through that element. Thus, to select
a bandwidth in this embodiment, one can select those x and y
coordinates that will open the desired pattern of shutters. It can
be readily appreciated that shutter array 1708 can be effectively
used to select desired .lambda.p and bandwidths from a filter array
that is not offset as in filter array 1704. In fact, because
embodiment 1700 has no moving mechanical parts, one can select and
rapidly change selection of .lambda.p and bandwidth as desired for
that particular application.
Example 17
Selection of Peak Wavelength and Bandwidth by Liquid Crystal
Shutters
[0181] FIG. 18 depicts an embodiment 1800 of this invention in
which filter array 1804 is a single array of filter elements and a
desired peak wavelength .lambda.p, that is in the same location
across the horizontal direction of filter array 1804. The vertical
direction of filter array 1804 depicts different wavelengths. As
with FIG. 17, an array of liquid crystal shutters 1708 ("shutter
array") is depicted in relationship to filter array 1804. In this
embodiment 1800, .lambda.p is selected by opening up the shutters
immediately above the portion of filter array 1804 that corresponds
to .lambda.p. To increase the intensity of the output beam,
additional shutters in the horizontal, or x direction can be
opened, thereby permitting additional radiation to pass through the
shutter array. Opening additional shutters in the x dimension can
increase the intensity further, until all of the shutters are
opened.
[0182] To select a bandwidth, one can open shutters in the y
dimension different from the location immediately corresponding to
.lambda.p. To increase the bandwidth, one can open additional
shutters in the y dimension from .lambda.p. Using this type of
embodiment, one can produce an output beam having any .lambda.p and
any bandwidth that are permitted by the range of wavelengths
incorporated into filter array 1804. Thus, to provide a beam having
greatest intensity at .lambda.p, one can open more shutters in the
x dimension of shutter array 1708 corresponding to .lambda.p than
shutters at any other wavelength.
[0183] In certain embodiments, one can produce an output beam
having a plurality of .lambda.p by opening more shutters at each of
two selected wavelengths than at other wavelengths. If desired, the
relative intensity at the two peak wavelengths can be the same or
can be different. Thus, using a shutter array as described in
Examples 16 and 17, one can select between a variety of different
output beams. One can select a beam having the output of a single
filter element .lambda.p, at a number of different intensities
depending on the output of the lamp and the number of open shutters
at .lambda.p. Alternatively, one can select an output beam having
.lambda.p and a bandwidth that depends on shutters at different
wavelengths. Moreover, one can select a bandwidth pattern wherein
the intensity of the output beam can be selected by opening up
different patterns of shutters. Because individual elements of the
shutter array 1708 can be controlled rapidly using electronic
signals addressed by x and y coordinates, these embodiments can
provide a high degree of flexibility and control over the
wavelengths in the output beam.
Example 18
Diode Array Illuminator
[0184] In other embodiments, illuminators are provide that comprise
a variety of diode emitters, selected to provide a variety of
different output wavelengths. By selecting which of such emitters
are activated, the central wavelength, bandpass, wavelength
variation, frequency, intensity and pulse duration can be
regulated. If desired, a computer system can be used along with a
series of diode emitters to provide preset control over the
different variables.
Example 19
Interrupter Designs
[0185] In certain embodiments of this invention, interrupters are
provided to permit production of electromagnetic radiation having
desired patterns. FIG. 19 depicts an embodiment of this invention
in which an interrupter 1900 has a disk portion 1904, 4 transparent
areas 1908 and an axis of rotation 1912. Interrupter 1900 is placed
in front of a beam of electromagnetic radiation (not shown) and the
beam is interrupted when an opaque portion of disk 1904 blocks the
radiation. When a transparent portion 1908 passes in front of the
beam, radiation can pass through the interrupter and can be
directed toward an object for illumination.
[0186] FIG. 20 depicts an embodiment of an interrupter of this
invention 2000, having a disk portion 2004 a transparent portion
2008 and an axis of rotation 2012. Upon rotation of interrupter
2000, when electromagnetic radiation passes through the narrowest
portion of transparent portion 2008, the intensity of radiation can
be minimized. When used in conjunction with a linear array of
filters as described herein, the transparent portion 2008 can be
used to adjust the wavelength bandpass. Upon rotation of the
interrupter so that a wider portion of the transparent portion 2008
is in front of the beam of radiation, more radiation or a wider
bandpass of radiation can pass through.
[0187] FIG. 21 depicts another embodiment of an interrupter of this
invention 2100, having a disk portion 2104, a transparent portion
2108, and an axis of rotation 2112. Upon rotation of interrupter
2100, light passing from a narrow end to a wider portion of 2108
can result in passage of a beam having higher intensity and/or
wider wavelength bandpass. As the transparent portion 2108
continues further, the beam can be progressively occluded by the
narrowing portion of 2108 and thereby the intensity and/or
wavelength bandpass can decrease.
[0188] FIG. 22 depicts a yet further embodiment of an interrupter
of this invention 2200, having a disk portion 2204 a spiral edge
2206 and an axis of rotation 2212. Upon rotation of interrupter
2200, a portion of a beam of electromagnetic radiation (not shown)
can be occluded by edge 2206. Further rotation can cause greater
occlusion of the beam, thereby decreasing intensity and/or
wavelength bandpass. When the interrupter 2200 rotates sufficiently
so that the beam passes by radial edge 2207, the intensity and/or
wavelength bandpass can abruptly change.
[0189] FIG. 23 depicts a further embodiment of an interrupter of
this invention 2300 having a disk portion 2304, an eccentric window
or transparent portion 2308 and an axis of rotation 2312. Upon
rotation of interrupter 2300, the transparent portion 2308 rotates
with respect to an underlying linear filter array (not shown),
thereby exposing different parts of the filter array with each
revolution of interrupter 2300. By exposing different parts of the
filter array, the wavelength of radiation passing through
transparent portion 2308 can vary over time.
[0190] The above examples and descriptions are by way of
illustration only, and are not intended to be limiting to the scope
of the invention. Other devices and systems embodying features of
this invention can be contemplated, and all of those devices and
systems are considered to be part of this invention.
INDUSTRIAL APPLICABILITY
[0191] Illuminators and systems for providing electromagnetic
radiation are useful for therapeutic applications involving
exposure of subjects to radiation of selected wavelength,
bandwidth, pulse frequency and pulse duration. The illuminators and
systems are also useful for applications in machine vision, grading
material characteristics, microscope illumination, catalysis in
radiation-triggered chemical reactions, testing of optical
assemblies and determining dispersion characteristics of materials.
Computer control systems permit the acquisition and analysis of
physiological and other information relating to the effects of
illumination.
* * * * *