U.S. patent application number 11/173076 was filed with the patent office on 2006-02-23 for curing light capable of multiple wavelengths.
This patent application is currently assigned to Discus Dental Impressions, Inc.. Invention is credited to Robert Hayman, Christopher N. Quan, Nancy N. Quan.
Application Number | 20060040231 11/173076 |
Document ID | / |
Family ID | 35732684 |
Filed Date | 2006-02-23 |
United States Patent
Application |
20060040231 |
Kind Code |
A1 |
Quan; Nancy N. ; et
al. |
February 23, 2006 |
Curing light capable of multiple wavelengths
Abstract
The present invention relates to a curing light having at least
one wavelength transformer for transforming a shorter wavelength
suitable for curing a dental composite into a longer wavelength
also suitable for curing a dental composite. The wavelength
transformer may be made of materials including organic dyes,
inorganic dyes, pigments, nanocrystals and combinations thereof.
The wavelength transformer can be of many different configurations.
The curing light also includes at least one heat sink which can be
made of a material including at least one phase change
material.
Inventors: |
Quan; Nancy N.; (North
Hills, CA) ; Hayman; Robert; (Los Angeles, CA)
; Quan; Christopher N.; (Quincy, MA) |
Correspondence
Address: |
DISCUS DENTAL IMPRESSIONS, INC.
8550 HIGUERA STREET
CULVER CITY
CA
90232
US
|
Assignee: |
Discus Dental Impressions,
Inc.
Culver City
CA
|
Family ID: |
35732684 |
Appl. No.: |
11/173076 |
Filed: |
June 30, 2005 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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60585224 |
Jul 2, 2004 |
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60658517 |
Mar 3, 2005 |
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60594297 |
Mar 25, 2005 |
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60631267 |
Nov 26, 2004 |
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60594327 |
Mar 30, 2005 |
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60664696 |
Mar 22, 2005 |
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Current U.S.
Class: |
433/29 |
Current CPC
Class: |
Y10S 362/80 20130101;
A61K 8/19 20130101; A61K 8/24 20130101; A61K 6/864 20200101; C08L
91/06 20130101; C08L 91/06 20130101; A61C 19/004 20130101; A61K
8/20 20130101; A61K 6/884 20200101; A61Q 11/00 20130101; A61K 6/884
20200101; A61K 6/884 20200101; Y10S 362/804 20130101; A61K 8/21
20130101 |
Class at
Publication: |
433/029 |
International
Class: |
A61C 1/00 20060101
A61C001/00 |
Claims
1. A dental curing light suitable for curing light curable dental
composite materials comprises: a light module housing having at
least one heat sink therein, said heat sink comprising at least one
mounting platform for mounting a light source; and a device
proximate the light source comprising at least one wavelength
transformer for transforming light of a shorter wavelength suitable
for curing light activatable composites into light of a longer
wavelength comprising at least a portion that is suitable for
curing light activatable composite.
2. The dental curing light of claim 1 wherein said wavelength
transformer is capable of capturing substantially all light in its
path and transforming at least a portion of the captured light into
a longer wavelength.
3. The dental curing light of claim 1 wherein said wavelength
transformer comprises one absorber/emitter having at least a
portion that is substantially transparent to an incident light, and
at least a portion capable of absorbing an incident light and
emitting light having a longer wavelength.
4. The dental curing light of claim 1 wherein at least one
wavelength transformer is positioned to capture substantially all
light in its path and transforming only a portion of the captured
light into a longer wavelength.
5. The dental curing light of claim 1 wherein at least one
wavelength transformer is configured to capture at least a portion
of the light emitted by the light source and transforming all of it
into a longer wavelength.
6. The dental curing light of claim 1 wherein said wavelength
transformer comprises an absorber/emitter comprising a material
selected from the group consisting of an organic dye, a pigment, an
inorganic dye, a semiconductor nanocrystal and combinations
thereof.
7. The dental curing light of claim 6 wherein said organic dye
comprises any fluorescent dye, any compound having an N-aryl
substituent and mixtures thereof.
8. The dental curing light of claim 7 wherein said the N-aryl
substituent selected from the group consisting of phenyl, naphthyl,
anthracyl, dinaphthyl, ditoluyl, bis(p-methylphenyl),
dianthracenyl, mixed aryl groups, substituted aryl groups and
combinations thereof.
9. The dental curing light of claim 6 wherein said organic dye
absorbs between about 350 nm to about 430 nm and emits between
about 450 nm and about 500 nm.
10. The dental curing light of claim 6 wherein said inorganic dye
comprises at least one element selected from the lanthanides.
11. The dental curing light of claim 6 wherein said semiconductor
nanocrystals are selected from the group consisting of CdS, CdSe,
CdTe and mixtures thereof.
12. The dental curing light of claim 1 wherein said wavelength
transformer comprises an absorber/emitter capable of absorbing a
relatively broad spectrum and transforming it into a relatively
broad spectrum at a higher wavelength.
13. The dental curing light of claim 1 wherein said wavelength
transformer comprises an absorber/emitter capable of absorbing a
relatively broad spectrum and transforming it into a relatively
narrow spectrum at a higher wavelength.
14. The dental curing light of claim 1 wherein said wavelength
transformer comprises an absorber/emitter capable of absorbing a
relatively narrow spectrum and transforming it into a relatively
narrow spectrum at a higher wavelength.
15. The dental curing light of claim 1 wherein said light source
comprises a cover comprising a wavelength transformer, an emitting
surface or combinations thereof.
16. The dental curing light of claim 15 wherein said emitting
surface comprises an absorber/emitter.
17. The dental curing light of claim 1 wherein at least one
wavelength transformer is stationary.
18. The dental curing light of claim 1 wherein at least one
wavelength transformer is adapted for rotation about a longitudinal
axis of the light module housing.
19. The dental curing light of claim 1 wherein said heat sink
comprises a phase change material.
20. The dental curing light of claim 1 wherein at least one light
source is selected from the group consisting of a lamp, an arc lamp
such as a halogen light source, semiconductor light emitting
devices, light-emitting chips such as an LED, a solid state LED, an
LED array, a fluorescent bulb and combinations thereof.
21. The dental curing light of claim 1 wherein said device
comprises a reflector.
22. The dental curing light of claim 1 wherein said wavelength
transformer comprises a beam splitter.
23. The dental curing light of claim 1 wherein said light module
housing comprises a reflecting surface.
24. A dental curing light capable of generating light of a multiple
wavelength suitable for curing light curable dental composite
materials comprises: a light module housing; and at least one heat
sink located in the light module housing, said heat sink includes
at least one mounting platform for mounting at least one light
source comprising at least one wavelength transformer for
transforming at least a portion of light emitted by the light
source suitable for curing light activatable composites into a
longer wavelength suitable for curing light activatable
composites.
25. The dental curing light of claim 24 wherein said wavelength
transformer is capable of capturing at least a portion of the light
emitted by the light source and transforming all captured light
into a longer wavelength.
26. The dental curing light of claim 24 wherein said wavelength
transformer is capable of capturing all light emitted by the light
source and transforming at least a portion of it into a longer
wavelength.
27. The dental curing light of claim 24 wherein said light source
comprises a cover comprising a wavelength transformer.
28. The dental curing light of claim 24 wherein said light source
comprises an emitting surface.
29. The dental curing light of claim 28 wherein said wavelength
transformer is present on at least a portion of the emitting
surface.
30. The dental curing light of claim 24 wherein said light source
comprises an emitting source comprising at least one edge.
31. The dental curing light of claim 30 wherein said wavelength
transformer is present on at least one emitting edge.
32. The dental curing light of claim 24 the light module housing
further comprises a beam splitter.
33. The dental curing light of claim 24 wherein said wavelength
transformer comprises an absorber/emitter comprising a material
selected from the group consisting of an organic dye, a pigment, an
inorganic dye, a semiconductor nanocrystal and combinations
thereof.
34. The dental curing light of claim 24 wherein said heat sink
comprises a phase change material.
35. A dental curing light suitable for curing light curable dental
composite materials comprises: a light module housing having at
least one heat sink located therein, said heat sink comprising at
least one mounting platform for mounting at least one light source;
and a device situated in the light path of the light source
comprising at least one wavelength transformer for transforming at
least a portion of the light emitted by the light source suitable
for curing light activatable composites into a longer wavelength
suitable for curing light activatable composites.
36. The dental curing light of claim 35 wherein said wavelength
transformer comprises at least one beam splitter and at least one
absorber/emitter comprising a chemical capable of absorbing
incident light and emitting light having a longer wavelength.
37. The dental curing light of claim 35 wherein said at least one
heat sink comprises a phase change material.
38. The dental curing light of claim 35 wherein said at least one
heat sink comprises a well having side walls.
39. The dental curing light of claim 35 wherein at least a portion
of the side walls is reflective.
40. The dental curing light of claim 36 wherein said at least one
wavelength transformer is configured to capture substantially one
beam coming from the beam splitter.
41. The dental curing light of claim 35 wherein said at least one
wavelength transformer is positioned at an oblique angle to the
emitted light path.
42. The dental curing light of claim 35 wherein said at least one
heat sink comprises a reflecting surface.
43. A dental curing light capable of generating light of more than
one wavelength suitable for curing light curable dental composite
material comprises at least one wavelength transformer capable of
transforming at least a portion of light emitted by a light source
suitable for curing a dental composite into a longer wavelength
suitable for curing a composite.
44. The dental curing light of claim 43 wherein said at least one
wavelength transformer comprises at least one absorber/emitter
having at least a portion that is substantially transparent to
incident light, and at least one portion comprising a chemical
capable of absorbing incident light and emitting light having a
longer wavelength.
45. The dental curing light of claim 43 wherein said at least one
wavelength transformer is configured to capture substantially all
light emitted by the light source.
46. The dental curing light of claim 43 wherein said at least one
wavelength transformer is configured to capture at least a portion
of light emitted by the light source.
47. The dental curing light of claim 43 wherein said at least one
wavelength transformer comprises at least one beam splitter.
48. The dental curing light of claim 43 wherein said wavelength
transformer comprises an absorber/emitter capable of absorbing a
relatively broad spectrum and transforming it into a relatively
broad spectrum at a higher wavelength.
49. The dental curing light of claim 43 wherein said wavelength
transformer comprises an emitter/absorber capable of absorbing a
relatively broad spectrum and transforming it into a relatively
narrow spectrum at a higher wavelength.
50. The dental curing light of claim 43 wherein said wavelength
transformer comprises an emitter/absorber capable of absorbing
substantially all wavelengths below about 400 nm, and transforming
them into a relatively narrow spectrum at a higher wavelength.
51. The dental curing light of claim 43 wherein said wavelength
transformer comprises an emitter/absorber capable of absorbing
substantially all wavelengths below about 400 nm, and transforming
them into a relatively broad spectrum at a higher wavelength.
52. The dental curing light of claim 43 wherein said wavelength
transformer comprises an emitter/absorber capable of absorbing a
relatively narrow spectrum at a low wavelength and transforming it
to a relatively narrow spectrum at a higher wavelength.
53. The dental curing light of claim 43 wherein light from the
curing light comprises multiple discrete peaks.
54. The dental curing light of claim 43 wherein light from the
curing light comprises a continuum between about 390 nm to about
500 nm.
55. The dental curing light of claim 43 wherein said light source
comprises an emitting source comprising at least one edge
comprising at least one wavelength transformer.
56. The dental curing light of claim 43 wherein said at least one
heat sink comprises a phase change material.
57. A curing light system capable of generating light of more than
one wavelength suitable for curing light curable dental composite
materials comprises: a light module housing having at least one
heat sink therein, said heat sink comprising at least one mounting
platform for mounting a light source; a device positioned proximate
the light source comprising at least one wavelength transformer for
transforming light of a shorter wavelength suitable for curing
light activatable composites into light of a longer wavelength
suitable for curing light activatable composites; and a light guide
comprising a formation adapted for supporting the curing light at a
target position.
58. The curing light system of claim 57 wherein said system further
comprises a lip retracting device comprising wing-like members.
59. The curing light system of claim 57 wherein said formation is
adapted for coupling the light guide to the wing-like members of
the lip retracting device.
60. The curing light system of claim 57 wherein said light module
housing comprises a support means for supporting the curing light
on said light guide.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. provisional
patent application Ser. No. 60/585,224, filed Jul. 2, 2004,
entitled "Dental Light Devices With Phase Change Heat Sink";
60/658,517, filed Mar. 3, 2005, entitled "Apparatus and Method For
Radiation Spectrum Shifting in Dentistry Application"; 60/594,297,
filed Mar. 25, 2005, entitled "Curing Light Having A Detachable
Tip"; 60/631,267, filed Nov. 26, 2004, entitled "Curing Light
Having A Reflector"; 60/594,327, filed on Mar. 30, 2005, entitled,
"Curing Light"; and 60/664,696, filed Mar. 22, 2005, entitled
"Curing Light Having A Detachable Tip"; the contents of all of
which are hereby incorporated by reference.
[0002] The present application includes claims that may be related
to the claims of co-pending U.S. patent applications, Ser. No.
10/______, to be concurrently filed, entitled "Illumination System
for Dentistry Applications"; Ser. No. 10/______, to be concurrently
filed, entitled "Voice Alert System for Dentistry Applications; the
contents of all of which are hereby incorporated by reference.
FIELD OF THE INVENTION
[0003] This invention relates to curing light devices for use in
dentistry. Specifically, this invention relates to curing light
devices for activating the curing of composite materials in
dentistry.
BACKGROUND OF THE INVENTION
[0004] In the field of tooth restoration and repair, dental
cavities are often filled and/or sealed with compounds that are
photosensitive to visible and/or ultraviolet light. These
compounds, commonly known as light-curable compounds, are placed
within dental cavity preparations or onto dental surfaces and are
cured when exposed to light from a dental curing light device.
[0005] Many light-curing devices are configured to be handheld
devices. Some of them are constructed with fiber optic light wands
designed for directing light from the light sources into the
patient's mouths. The light sources may be lamps, halogen bulbs or
light-emitting diodes (LED). One end of the light wand may be
placed close to the light source so that the light emitted from the
light source may be directed into the light wand. Some of the light
wands are not configured to capture all the light that is generated
by the light sources, particularly light that is emitted from LEDs,
which may be emitted at angles of up to about 120.degree.. This
inefficiency in capturing most of the available light output may
contribute to excessive heat generation, which may lead to limited
run times for the curing devices.
[0006] One method for overcoming the limitations of light capture
disclosed in the prior art is to improve the efficiency of the
curing devices by placing the light source(s) of the light-curing
devices at the tip of the light-curing devices, so that all of the
light generated by the light source(s) may be directed towards a
desired location within the patients' mouths. This, however, does
not overcome the run time problem mentioned above. At the same
time, this method may create the problem of having the light source
too close to the patient's mouth, causing discomfort to the patient
if the hot tip of the curing device happens to come in contact to
the sensitive tissues of the patient's mouth.
[0007] One way of overcoming the problem of having excessive heat
from coming too close to the patient's mouth is to mount the light
source(s) on a heat sink that may generally conduct the heat away
from the tip of the light-curing device. This, however, only
minimally solves the runtime problem mentioned above.
[0008] In addition, multiple light sources used in making a curing
light capable of multiple wavelengths may further add to excessive
heat generation problems if the light sources generate a wide
spectrum of light, leading to more heat that needs to be diverted
away from the light source. Even with light sources generating just
the desired wavelength for composite curing, heat generation is
still a problem. Consequently, elaborate cooling systems are needed
to handle heat, possibly creating a large, heavy and expensive
curing light.
[0009] Accordingly, there remains a need for a device capable of
curing restorative compounds containing different initiators.
SUMMARY OF THE INVENTION
[0010] The present invention relates to a dental curing device
suitable for curing light curable dental composite material. The
device includes a light module housing having a substantially
cylindrical shape including a substantially hollow interior with at
least one heat sink, located in the light module housing. The heat
sink includes at least one surface or mounting platform for
locating, positioning or mounting a light source, for example, a
lamp, an arc lamp such as a halogen light source, semiconductor
light emitting devices, light-emitting chips such as an LED, a
solid state LED, an LED array, a fluorescent bulb, and so on. Light
emitted by the light source has an emission spectrum including at
least one wavelength capable of initiating curing of a composite. A
device situated in the proximity of the light source includes at
least one wavelength transformer for capturing substantially all
the light in its path emitted by the light source and transforming
at least a portion of the captured light into a longer wavelength,
which is also capable of initiating a chemical reaction to cure the
dental composite material.
[0011] At least one wavelength transformer includes at least one
absorber/emitter having at least a portion that is substantially
transparent to the incident light, and at least one portion capable
of absorbing the incident light and emitting light having a longer
wavelength. In one embodiment, at least one wavelength transformer
is configured or positioned to capture substantially all the
emitted light and to transform only a portion of the capture light
into a longer wavelength. In another embodiment, at least one
wavelength transformer is configured or positioned to capture at
least a portion of the light emitted by the light source and to
transform all captured light into a longer wavelength. In one
aspect, at least one wavelength transformer is stationary. In
another aspect, at least one wavelength transformer is adapted for
rotation about a longitudinal axis of the light module housing.
[0012] In one other embodiment, the light source includes an
emitting surface. In another embodiment, the light source includes
at least one emitting edge.
[0013] In a further embodiment, at least one wavelength transformer
may be in a direct path of the emitted light. In a yet further
embodiment, at least one wavelength transformer may be at an
oblique angle to the direct path of the light emitted by the light
source.
[0014] The present invention also relates to a dental curing device
suitable for curing light curable dental composite materials. The
curing device includes a light module housing having a
substantially cylindrical shape including a substantially hollow
interior with at least one heat sink located in the light module
housing. The heat sink includes at least one surface or, mounting
platform for locating, positioning or mounting at least one light
source, as noted above. Light emitted by the light source includes
a wavelength suitable for curing light curable dental composite
materials. In one aspect, a light source includes at least one
wavelength transformer for capturing at least a portion of the
light emitted by the light source and transforming all captured
light into a longer wavelength, which is also suitable for curing
light curable dental composite material. In another aspect, the
light source includes at least one wavelength transformer for
capturing all light emitted by the light source and transforming at
least a portion of it into a longer wavelength such that the
resultant light directed at the light curable dental composite
material includes a portion having the emitted wavelength and a
portion having a longer wavelength.
[0015] The present invention further relates to a dental curing
light suitable for curing light curable dental composite materials.
The curing device includes a light module housing having a
substantially cylindrical shape including a substantially hollow
interior with at least one heat sink located in the light module
housing. The heat sink includes at least one surface or mounting
platform for locating, positioning or mounting a light source, as
noted above. Light emitted by the light source includes a
wavelength suitable for curing light curable dental composite
materials. A device situated in the light path of the light source
includes at least one wavelength transformer for transforming at
least a portion of the light emitted by the light source into a
longer wavelength. The wavelength transformer includes at least one
beam splitter and at least one absorber/emitter including a
chemical capable of absorbing the incident light and emitting light
having a longer wavelength.
[0016] In one embodiment, at least one wavelength transformer is
configured or positioned to substantially capture one beam coming
from the beam splitter. In another embodiment, at least one
wavelength transformer is at an oblique angle to the emitted light
path. In a further embodiment, at least one wavelength transformer
is at substantially right angles to the emitted light path.
[0017] In one embodiment, the heat sink includes at least one
elongated heat sink located in the light module housing, with the
proximal end of the heat sink being situated close to a proximal
end of the housing and at least one surface or mounting platform
located at the proximal end of the elongated heat sink.
[0018] In another embodiment, at least one of the heat sinks may be
of any shape situated close to a proximal end of the housing and at
least one surface or mounting platform located at the proximal face
or portion of the heat sink.
[0019] Furthermore, the present invention relates to a dental
curing light capable of generating light of more than one
wavelength suitable for curing light-curable dental composite
material. The curing light includes at least one wavelength
transformer capable of transforming at least a portion of light
emitted by a light source, as disclosed above, into a longer
wavelength which is also suitable for curing light activatable
composites. In one embodiment, at least one wavelength transformer
includes at least one absorber/emitter having at least a portion
that is substantially transparent to the light incident on it, and
at least one portion including a chemical capable of absorbing the
incident light and emitting light having a longer wavelength. In
one aspect, at least one wavelength transformer is configured or
positioned to capture substantially all of the emitted light. In
another aspect, at least one wavelength transformer is configured
or positioned to capture at least a portion of the light emitted by
the light source. In a further aspect, at least one wavelength
transformer is stationary. In still another aspect, at least one
wavelength transformer is adapted for rotation about a longitudinal
axis of the light module housing.
[0020] Still furthermore, the present invention relates to a dental
curing light capable of generating light of more than one
wavelength suitable for curing light curable dental composite
material. The curing light includes at least one wavelength
transformer for transforming at least a portion of the light
emitted by the light source into a longer wavelength which is also
capable of activating a light activatable composite. At least one
wavelength transformer includes at least one beam splitter and at
least one absorber/emitter includes a chemical capable of absorbing
the incident light and emitting light having a longer
wavelength.
[0021] In one embodiment, at least one wavelength transformer is
configured or positioned to capture one beam coming from the beam
splitter. In another embodiment, at least one wavelength
transformer is at an oblique angle to the emitted light path. In a
further embodiment, at least one wavelength transformer is at
substantially right angles to the emitted light path.
[0022] Yet furthermore, the present invention relates to a dental
curing light capable of generating light of more than one
wavelength suitable for curing light curable dental composite
materials. The curing light includes at least one wavelength
transformer for transforming the shorter wavelength portion of the
light emitted by a light source, described above, which is
unsuitable for curing composites, into a longer wavelength, both
the longer wavelength portion of the emitted light and transformed
light are capable of activating light activatable composites. At
least one wavelength transformer includes at least one filter
including an absorber/emitter capable of absorbing substantially
all the shorter wavelength of light emitted by the light source,
and transforming it into a longer wavelength. In one aspect, the
emitter/absorber is capable of absorbing a relatively broad
spectrum, below about, for example, 400 nm, and transforming it
into a relatively broad spectrum at a higher wavelength, for
example, about 450 nm. In another aspect, the emitter/absorber is
capable of absorbing a relatively broad spectrum, below about, for
example, 400 nm, and transforming it into a relatively narrow
spectrum at a higher wavelength, for example, about 470 nm. In yet
another aspect, the emitter/absorber is capable of absorbing
substantially all wavelengths, below about, for example, 400 nm,
and transforming them into a higher wavelength, for example, about
470 nm. In still yet another aspect, the emitter/absorber is
capable of absorbing substantially all wavelengths, below about,
for example, 400 nm, and transforming them into a relatively broad
spectrum at a higher wavelength, for example, about 450 nm. In
still yet a further aspect, the absorber/emitter is capable of
absorbing a relatively narrow spectrum at a low wavelength and
transforming it to a relatively narrow spectrum at a higher
wavelength. In one embodiment, at least one wavelength transformer
is stationary. In another embodiment, at least one wavelength
transformer is adapted for rotation about the longitudinal axis of
the light module housing.
[0023] The light module housing of any of the above disclosed
curing lights may include at least one reflecting surface. In one
embodiment, the at least one reflecting surface may be present in
the direct path of the emitted light. In another embodiment, the at
least one reflecting surface may be present in an oblique angle to
the emitted light.
[0024] The light source of any of the above disclosed curing lights
may include a primary and a secondary heat sink. The heat sink may
include a material that can more efficiently remove or divert heat
from a curing light device when a reduced weight of heat sink
material is used for better portability.
[0025] In one aspect, the heat sink may have a reflective surface.
In another aspect, the heat sink may include a surface or a
mounting platform. The surface or mounting platform may also have a
reflective surface.
[0026] In one embodiment of the above disclosed invention, the heat
sink includes a material that can more efficiently remove or divert
heat from a light source or sources with a given weight of heat
sink material when compare to a heat sink made of a solid block of
thermally conductive material such as metal.
[0027] In another embodiment of the above disclosed invention, the
heat sink includes at least one suitable phase change material
including organic materials, inorganic materials and combinations
thereof. These materials can undergo substantially reversible phase
changes, and can typically go through a large, if not an infinite
number of cycles without losing their effectiveness.
[0028] In a further embodiment of the above disclosed invention,
the output of the light spectrum from the curing device may include
of multiple discrete peaks.
[0029] In yet a further embodiment of the above disclosed
invention, the output of the light spectrum from the curing device
may be substantially a continuum.
[0030] The wavelength transformers of the present invention may be
positioned at any distance from the light source. In one
embodiment, the transformer maybe formed directly on the light
source. In another embodiment, the transformer may be positioned at
a few mm away from the light source.
[0031] In one embodiment, a light source may include edge emitting
LEDs or LED arrays. In one aspect, the wavelength transformer
capable of transforming all captured light in its path may be
formed onto at least one edge of the emitting edges. In another
aspect, the wavelength transformer capable capturing all light in
its path and transforming portions of it may be formed onto all
emitting edges.
[0032] The curing lights of the present invention may include a
light transport device at the proximal end of the housing. In one
aspect, the light transport device may be a light guide. In another
aspect, the light transport system may comprise a focusing dome
that may also be capable of varying the beam diameter of the light
exiting the curing light device. In a further aspect of the
invention, the light transport system may be a tacking tip. In a
further aspect, the light transport device may be a positioning
light guide adapted for positioning the curing light to a
target.
BRIEF DESCRIPTION OF THE DRAWINGS
[0033] FIG. 1 shows a cross-sectional view of the curing light of
the present invention.
[0034] FIG. 2 shows another cross-sectional view of an embodiment
of the present invention, depicting the arrangement of the mounting
platform and the wavelength transformer of the present
invention.
[0035] FIG. 3A shows a cross-sectional view of another embodiment
of the arrangement of the mounting platform and wavelength
transformer.
[0036] FIG. 3B shows a perspective view of an alternative
embodiment of a wavelength transformer including a patterned
absorber/emitter.
[0037] FIG. 3C shows a perspective view a further alternative
embodiment of a wavelength transformer according to principles of
the invention.
[0038] FIG. 4 shows a cross-sectional view of yet another
embodiment of the present invention including a mounting platform,
beam splitter and wavelength transformer.
[0039] FIG. 5 shows a cross-sectional view of still yet another
embodiment of the present invention including an arrangement of the
mounting platform, beam splitter and wavelength transformers.
[0040] FIG. 6 shows a cross-sectional view of an embodiment of the
curing light module using a reflector for reflecting portions of
the light.
[0041] FIG. 7 shows a cross-sectional view of an embodiment of the
curing light module including a reflector equipped with a
wavelength transformer.
[0042] FIG. 8 shows a perspective view of an embodiment of the
curing light device having a light transport system such as a light
guide or an optically conductive cable.
[0043] FIG. 9A shows a perspective view of a light guide that may
serve to position the light source in the mouth of a patient.
[0044] FIG. 9B shows a perspective view of a light guide mated to a
lip retractor according to principles of the invention;
[0045] FIG. 9C shows the light guide and lip retractor of FIG. 9B
supporting a curing light according to principles of the
invention.
[0046] FIG. 10 shows a perspective view of an embodiment of a light
source including a protective dome or cover with wavelength
transformer.
[0047] FIG. 11 shows a perspective view of an embodiment of the
curing light device having a tacking tip.
[0048] FIG. 12 shows a handgrip having coupling means for coupling
to the light guide.
[0049] FIG. 13 shows a cross-sectional view of an embodiment of the
curing light device having a plurality of LEDs mounted on a heat
sink in a manner that the emitted light passes through a wavelength
transformer and is collected by a reflector apparatus and focused
by a lens means.
[0050] FIG. 14A shows a cross-sectional view of an embodiment of
the curing light device having a plurality of LEDs, each having its
own heat sink, that the emitted light passes through a wavelength
transformer and is collected by a reflector apparatus and focused
by a lens.
[0051] FIG. 14B shows a cross-sectional view of a curing light
according to one embodiment of the invention.
[0052] FIG. 15 shows a cross-sectional view of an embodiment of the
curing light device where the elongated heat sink has a curved
structure for positioning an LED array.
[0053] FIG. 15a shows a cross-sectional view of an embodiment of
the curing light device where the heat sink has a well structure
for mounting LEDs.
[0054] FIG. 16 shows a cross-sectional view of an embodiment of the
curing light device where the elongated heat sink has a planar
mounting platform for positioning a light source.
[0055] FIG. 17 shows a perspective view of a curing light device
according to principles of the invention.
[0056] FIG. 18 shows a battery charger module suitable for use with
the present invention.
[0057] The detailing description set forth below is intended as a
description of the presently preferred embodiments provided in
accordance with aspects of the present invention and is not
intended to represent the only forms in which the present invention
may be prepared or utilized. It is to be understood, however, that
the same or equivalent functions and components may be accomplished
by difference embodiments that are also intended to be encompassed
within the spirit and scope of the invention.
[0058] Unless defined otherwise, all technical and scientific terms
used herein have the same meaning as commonly understood to one of
ordinary skill in the art to which this invention belongs. Although
any methods, devices and materials similar or equivalent to those
described herein may be used in the practice or testing of the
invention, the exemplified methods, devices and materials are now
described.
[0059] A dental curing light useful for curing or activating
light-activated materials is disclosed. The present invention has
applications in a variety of fields, including but not limited to
medicine and dentistry, where light-activated materials including a
photoinitiator or photoinitiators are used. As an example, a
photoinitiator absorbs light of a particular wavelength and
initiates the polymerization of monomers into polymers.
[0060] In an exemplary embodiment, light-activated materials
including a single photoinitiator or multiple photoinitiators may
be applied to a surface of, such as a tooth, and later cured by
light of a wavelength or wavelengths that activates the
photoinitiator or photoinitiators. The light used not only is of a
wavelength to which the photoinitiator is sensitive, but also of a
power level to cause curing for certain durations of time. Although
the light used to activate the photoinitiator is of a wavelength to
which a photoinitiator is sensitive, the light may come from a
variety of sources, including a lamp, an arc lamp such as a halogen
light source, semiconductor light emitting devices, light-emitting
chips such as an LED, a solid state LED, an LED array, a
fluorescent bulb, and so on. The present invention discloses, for
example, light systems that use semiconductor chips as their source
of light for a compact curing light device.
[0061] The typical photo-sensitizers used in composite curing
include Camphorquinone (CQ), which absorbs light at about 465 nm,
and phenyl-propanedione (PPD), which absorbs light at about 390 nm.
Dental curing lights having multiple wavelengths suitable for
curing curable composites usually include output wavelengths
encompassing the absorbing wavelengths of these two typically used
photo-initiators. The output is generally a composite spectrum
generated by LEDs or LED arrays emitting different wavelengths. The
present invention includes a curing light capable of curing all
composites by means of a light source as mentioned above, emitting
a single peak wavelength. The light source may include an emitting
surface or at least one emitting edge such as an edge emitting chip
noted above.
[0062] FIG. 1 shows the cross-section of a curing light 100 having
a light module housing 101 having a distal end 111, a proximal end
112, a handle 102 towards its distal end and a neck and head
portion 103 on its proximal end at an angle to the handle portion
102. The light module housing 101 includes a substantially
cylindrical shape having a substantially hollow interior 101a with
at least one heat sink 120 located in the light module housing 101.
The heat sink 120 includes at least one surface or mounting
platform 121 for locating, positioning or mounting a light source
130, as noted above.
[0063] The light module housing may include a wavelength
transformer 140. The wavelength transformer 140 may be present in
the emitting surface of the light source 131, in front of the light
source 130 towards the proximal end 112 of the light module
housing, or at least one emitting edge of an edge emitting source,
or in the light path of the light source, as shown in FIG. 1.
[0064] For example, in FIG. 2, the light source 130 may include a
single LED 131, emitting light, for example, in the blue range,
suitable for curing light activatable composites. Also as shown in
FIG. 2, the heat sink 120 has an elongated shape, though any other
shape is also useful. The elongated heat sink 120 includes a distal
end 120a and a proximal end 120b, and is positioned such that the
proximal end 120b is situated towards the proximal end 112 of the
light module housing 101. One surface or mounting platform 121, as
shown, is located towards the proximal end 120b of the elongated
heat sink 120. In other embodiments, one mounting platform 121 may
be present towards the distal end 120a of a heat sink 120, if the
heat sink 120 is an elongated heat sink, as shown for example in
FIG. 5, or on a proximal face or portion of the heat sink 120 if
the heat sink 120 is of any other shape, as shown for example in
FIG. 4.
[0065] Light emitted from the LED 131 includes an emission spectrum
including at least one wavelength capable of initiating curing of a
composite. A device situated in the light path of the LED includes
at least one wavelength transformer 140 for transforming at least a
portion of the light emitted by the LED 131 into a longer
wavelength, which is also capable of initiating a chemical reaction
to cure the dental composite material.
[0066] The wavelength transformer 140 includes at least one
absorber/emitter. The absorber/emitter may be of any substances
that absorbs electromagnetic waves, for example, in the blue
wavelength range, and then luminesce, in particular fluoresce, when
optically excited. Such chemical compounds may include organic and
inorganic dyes or pigments.
[0067] Organic dyes may include any fluorescent dye having at least
one amine moiety substituted with at least two aryl groups, and
compounds having N-aryl substituents which exhibit reduced pH
sensitivity and enhanced stability to protonation. Examples of an
aryl group include phenyl, naphthyl, anthracyl, dinaphthyl,
ditoluyl, bis(p-methylphenyl), dianthracenyl, mixed aryl groups
such as phenylnaphthyl and phenyltoluyl, or substituted aryl groups
such as toluyl, some of these are disclosed in U.S. Pat. No.
6,627,111, "Organic light emitting displays and new fluorescent
compounds", incorporated herein by reference. Some embodiments
include dyes that absorb between about 350 to about 430 nm and emit
between about 450 nm and to about 500 nm, for example, DAPI
(4',6-Diamidino-2-phenylindole, 2HCl, absorbing at about 359 nm and
emitting at about 461 nm); HOE 33258
(2-[2-(4-Hydroxyphenyl)-6-benzimidazoyl]-6-(1-methyl-4-piperazyl)-benzimi-
dazole, 3HCl), absorbing at about 346 nm and emitting at about 460
nm; HOE 33342
(2'-(4-Ethoxyphenyl)-5-(4-methyl-1-piperazinyl)-2,5'-bi-1H-benzimid-
azole, 3HCl), absorbing at about 346 nm and emitting at about 460
nm; 7-Diethylamino-3-(4-maleimidylphenyl)-4-methylcoumarin,
absorbing at about 387 nm and emitting at about 465 nm;
2-(4'-(Dimethylamino)phenyl)-6-methylbenzothiazole
6-Methyl-BenzoThiazole-Aniline-2-Methyls, absorbing at about 356
nm, and emitting at about 437 nm, and combinations thereof.
[0068] Useful inorganic dyes may include, for example, elements
from the group of lanthanides, including the element Y, La, Ce, Pr,
Nd, Sm, Yb or Lu. Some examples may include phosphors such as
yttrium aluminum garnet doped with praseodymium and cerium
(YAG:Pr+Ce), strontium sulfide doped with europium (SrS:Eu),
strontium thiogallate, or any other suitable phosphor. Other
examples of such dyes are disclosed in the German Patent Document
DE 37 03 495 A1, incorporated herein by reference.
[0069] The dyes may also be, for example, in pigment form. Some
examples of commercially available ones include Lumogen.RTM. dyes
(available from BASF AG, Ludwigshafen), Lumilux.RTM. pigments
(available from Riedel de Haen GmbH, Seelze), or mixtures
thereof.
[0070] The wavelength transformer 140 includes at least one
absorber/emitter 141 having at least a portion that is
substantially transparent to the incident light, and at least one
portion capable of absorbing the incident light and emitting light
having a longer wavelength. In the embodiment exemplified in FIG.
2, at least one wavelength transformer is configured or positioned
to capture substantially all of the emitted light while
transforming only a portion of the capture light into a longer
wavelength.
[0071] The absorber/emitter 141 may be positioned at any distance
away from an emitting surface, from a few .mu.m to a few mm,
including right at the light source or emitting surface or edge, or
incorporated therewith into the construction of the emitting
surfaces or edges. Such incorporation of the absorber/emitter may
be accomplished by sputtering, thin film deposition, vapor
deposition, lithographic printing, coating, or other techniques
known in the art.
[0072] In one aspect, the light source emits a narrow band and the
portion of light being transformed may be of a wavelength that is
suitable for activating the curable composite. In another aspect,
the light source emits a broader band of wavelengths and the
portion of light being transformed may be of a shorter wavelength
than that is suitable for activating the curable composite.
[0073] In another embodiment, as shown in FIG. 3A, at least one
wavelength transformer including an absorber/emitter may be
configured or positioned to capture at least a portion of the light
emitted by the light source and transforming all captured light.
The absorber/emitter 141 may be positioned at any distance away
from an emitting surface, from a few .mu.m to a few mm.
[0074] FIG. 3B shows an alternative embodiment of the wavelength
transformer 140 including an absorber/emitter. The absorber/emitter
in this alternative embodiment has a checkerboard pattern of
absorbing/emitting material deposited on a clear substrate, such as
glass. The pattern in this embodiment may be deposited using
photoresist techniques or by various thin film deposition
techniques including sputtering. The present invention is not
limited to the patterning techniques listed here. Further alternate
embodiments include patterns other than checkerboard.
[0075] For an absorber/emitter capable of capturing all of the
emitted light and transforming only a portion of it into a longer
wavelength, the dye, pigment or mixtures thereof, may be present in
at least at portion of the absorber/emitter. In one embodiment, the
absorber/emitter has a matrix of domains including dyes, pigments
or mixtures thereof, surrounded by domains that are substantially
transparent to the incident light. The domains may be of any size,
including domains of the size of a few molecules, to domains that
may be almost half the size of the entire absorber/emitter. In
another embodiment, the configuration of the absorber/emitter may
have two separate portions, one portion including a dye, pigment or
mixtures thereof, capable of absorbing a shorter wavelength and
emitting a longer wavelength and the other portion being
transparent to the incident light. In one other embodiment, the
configuration of the absorber/emitter may have a matrix of domains
of any shape and size, some of which may include a dye, pigment or
mixtures thereof, capable of absorbing a shorter wavelength and
emitting a longer wavelength and the others being transparent to
the incident light. In a further embodiment, the configuration of
the absorber/emitter may have a matrix of stripes having a dye,
pigment or mixtures thereof, interposed with stripes of having no
dye or pigment. The coating of dye, pigment or mixtures thereof may
be deposited in a variety of patterns including, straight line
patterns such as parallel longitudinal lines, parallel transverse
lines; rectangular patterns; circular or arcuate patterns; dot
patterns such as symmetrical or unsymmetrical patterns of dots, and
combinations thereof. The patterns may be formed by any of a number
of coating methods including slot coating, pattern coating, and
rotogravure coating and the like. Suitable methods for applying
selected patterns include, for example, slot coating, transfer
coating, and rotogravure coating, may be used.
[0076] For the absorber/emitter capable of capturing at least a
portion of the emitted light and transforming substantially all of
the captured light into a longer wavelength, the dye, pigment or
mixtures thereof may be present in substantially all regions of the
absorber/emitter.
[0077] An organic dye, pigment or mixtures thereof may be used as
an absorber/emitter in a wavelength transformer. Examples are
discussed in, for example, U.S. Pat. No. 5,126,214 to Tokailin et
al. (which discloses a fluorescent material part that emits in a
visible light range from red to blue); and U.S. Pat. No. 5,294,870
to Tang et al. (which makes reference to the use of both organic
and inorganic dye materials), the contents of which are
incorporated herein by reference.
[0078] An absorber/emitter capable of capturing at least a portion
of the light emitted by the light source and transforming all
captured light, the absorber/emitter may have a matrix of a uniform
coating or layer of a dye, pigment or mixtures thereof in its
entirety.
[0079] In one aspect of the invention, at least one wavelength
transformer may be fixed in the light path of the light source. In
another aspect, at least one wavelength transformer is adapted for
rotation about the longitudinal axis of the light module housing.
In a further aspect, at least one wavelength transformer may be,
for example, in the form of an interchangeable filter disk,
permanently or reversibly connected to a light guide. One
embodiment of a light guide may be as shown in FIG. 10.
[0080] In one embodiment, the wavelength transformer includes a
substrate, an absorber/emitter matrix capable of absorbing a lower
wavelength of light and transforming or re-emitting that light at a
longer wavelength, and a cover element.
[0081] The dye, pigment or mixtures thereof, may be coated on any
substrate such as a sheet or a plate of glass, a polymer film such
as polymethylmethacrylate (PMMA), polyethylene (PE), polypropylene
(PP), polystyrene (PS), polycarbonate (PC), polyvinylchloride
(PVC), polyester terephthalate (PET) or combinations thereof, to
form the absorber/emitter matrix.
[0082] In one embodiment, the wavelength transformer 140 may be
capable of capturing substantially all of the light emitted by the
emitting source, and may be positioned directly over at least a
portion of the emitting source and transforming all of the captured
light. In another embodiment, the wavelength transformer 140 may be
capable of capturing substantially all of the light emitted by the
emitting source, and may be positioned directly over the emitting
source and transforming at least a portion of the captured
light.
[0083] In one embodiment, the emitting source 131 may include an
edge emitting chip. In one aspect, the absorber/emitter 141 is
electrophoretically deposited, stenciled, screen printed, coated or
sputtered directly onto at least one of the emitting edges so that
at least one of the emitting edges include a wavelength transformer
140. In another aspect, the absorber/emitter 141 may be directly
deposited, coated or sputtered onto the emitting edges so that at
least a portion of each emitting edge includes a wavelength
transformer 140. In a further aspect, the absorber/emitter 141 may
be positioned directly over at least one of the edges or all of the
emitting edges, depending on whether the transformer is capable is
transforming all or apportion of the light it captures.
[0084] In the present invention, a handheld curing device is
desirable. Such devices tend to have restricted spaces. Hence
thermal management is important. Heat generation tends to cause
run-time problems. Multiple light sources used in making a curing
light capable of multiple wavelengths might further add to
excessive heat generation problems, particularly if the light
sources generate a wide spectrum of light that is then passed
through filters and/or bandwidth adjusters to remove some of the
light that is outside of the wavelength ranges suitable for
activating light curable composites, leading to more heat that
needs to be diverted away from the light source or sources. Even
with light sources that generate just the desired wavelength for
composite curing, heat generation may still present a problem,
leading to the need for elaborate cooling systems. Multiple LEDs
such as arrays emitting one wavelength may also present problems if
the materials used for absorber/emitter have broad emission
photoluminescence spectra that require additional optical filters
for spectra correction. These additional optical filters may also
introduce additional loss of intensity. Thus, the efficiency of a
wavelength transformer may depend on the broadness of the emission
spectra of the absorber/emitter, i.e., how much light that is
emitted by components of the wavelength transformer is outside of
the usable ranges of the photoinitiators employed in the curing
composites. The more desirable ones are those capable of
re-emitting a narrower spectrum of light at a longer wavelength, or
re-emitting a broad spectrum having a portion that overlaps another
usable wavelength range.
[0085] The present invention also includes wavelength transformers
including absorber/emitters capable of absorbing light at
wavelengths lower than those suitable for curing activatable
composites and transforming them into longer wavelengths useful for
curing activatable composites. This type of wavelength transformers
may accommodate light sources emitting a broader spectrum, for
example, having a portion of light outside the wavelength suitable
for curing light activatable composites, for example, on the
shorter wavelength side. For these wavelength transformers, some of
them are capable of emitting a narrow band or a broader band, all
within the suitable range for activating a light curable composite.
The wavelength transformer can make use of substantially all
emitted light and therefore help solve at least a portion of the
heat problem generally present in light sources emitting a wide
spectrum, as noted above.
[0086] In one embodiment, a wavelength transformer 140 may include
an organic dye, alone or in combination with organic dyes pigments
or combinations thereof, for example, an inorganic-based material
that provides a narrower photoluminescence emission spectrum when
optically stimulated by a lower wavelength photon energy source. An
example of such inorganic-based materials includes semiconductor
nanocrystals.
[0087] In another embodiment, the absorber/emitter 141 includes
matrices having, for example, semiconductor nanocrystals uniformly
dispersed in a transparent organic binding material. The wavelength
of the re-emitted light may be tunable by altering the size or the
size distribution of the semiconductor nanocrystals.
[0088] The excitation of some of these nanocrystals is apparently
unaffected by the excitation wavelengths, thus enabling a choice of
emission spectrum wavelengths by the use of a single excitation
wavelength, for example, an LED emitting at a wavelength capable of
initiating curing of a dental composite.
[0089] Examples of semiconductor nanocrystals, such as passivated
CdSe crystal, in the size range of about 10 to about 200 Angstroms,
are known to be widely tunable to emit up through the visible
spectrum, as disclosed in U.S. Pat. No. 6,608,439, incorporated
herein by reference. They may also be controllably fabricated with
narrow size distributions from scalable colloidal precipitation and
other techniques known in the art.
[0090] It is also known that a layer or layers containing the
semiconductor nanocrystals may be fabricated into a stable film or
films by patterned photolithographic techniques. The
absorber/emitter 141 may include at least one layer. As noted
before, the absorber/emitter 141 may also be positioned at any
distance away from an emitting surface, from a few .mu.m to a few
mm, or even directly over the emitting source.
[0091] The semiconductor nanocrystals may include, for example, the
group of the semiconductor compounds CdS, CdSe, CdTe and mixtures
of two or more of the semiconductor compounds. Organic binding
material for use with nano-crystals may be the same material
disclosed above in relationship to the substrate, or other
polymers, oligomers, monomers or a mixture of them.
[0092] The benefits of using semiconducting nanocrystals are
related to their fundamental properties, as described in the
available research literature, for example, a review presented by
A. P. Alivisatos in "Semiconductor clusters, nanocrystals, and
quantum dots," Science 271 (Feb. 16, 1996) 933-937; and an article
by C. B. Murray, D. J. Norris and M. G. Bawendi, "Synthesis and
characterization of nearly monodisperse CdE (E=S, Se, Te)
semiconductor nanocrystallites," J. Am. Chem. Soc. 115 (1993)
8706-8715, contains detailed art about the synthesis and properties
of nanocrystals from the cadmium family.
[0093] Methods of fabricating semiconductor nanocrystals can be
found in U.S. Pat. No. 5,559,057 to Goldstein (disclosing the
method of manufacturing thin films from nanocrystal precursors);
and U.S. Pat. No. 5,525,377 to Gallagher et al. (disclosing the
method of making doped encapsulated semiconductor nanocrystallites
for use in thin films for electroluminescent displays), both of
which are incorporated herein by reference.
[0094] In a further embodiment, a combination of nanocrystals and
an organic transport layer maybe used as a wavelength transformer.
Examples of semiconductor nanocrystals in combination with an
organic electron transport layer to transform wavelengths are
disclosed in U.S. Pat. No. 5,537,000 to Alivisatos et al., all of
which are incorporated herein by reference.
[0095] For example, organic electron transport layers may be
multifunctional linking agents such as, for example, difunctional
thiols, and linking agents containing a thiol group and a carboxyl
group. In particular, dithiols described are those having the
formula H--S--R--S--H, where R is an organic group which provides
sufficient spacing between the sulfur atoms at the opposite ends of
the molecule to permit the respective thiol groups on the opposite
ends of the molecules to respectively bond to adjacent
nanocrystals, or to a nanocrystal at one end and a substrate or
support surface on the other end. Thus, R may include an organic
moiety, such as an alkylene or an arylene, containing from 4 to 8
carbon atoms. Examples of such dithiol organic compounds include
1,4-dithiol n-butane; 1,5-dithiol n-pentane; 1,4-dithiol
cyclohexane; 1,6-dithiol n-hexane; 1,7-dithiol n-heptane; and
1,8-dithiol n-octane. Such shorter chain molecules are more
desirable over longer chain molecules to prevent or inhibit the
linking agent from doubling back to adhere on both ends to the
material to which the semiconductor nanocrystals is being bonded.
However, it may be possible to also use longer chain linking agents
in some instances, particularly when multiple monolayers of the
nanocrystals are being applied over a support media.
[0096] The wavelength transformer may be fabricated in any shape
that is suitable for use in the curing light, such as a
rectangular, triangular, circular or elliptical flat film; a curve
film having a concave or convex shape; a lens form having a concave
or convex shape, or other configurations that may be designed for
capturing a portion or all of the emitted light.
[0097] As noted above, despite the discussion for desiring dyes or
pigments or nanocrystals capable of re-emitting narrower spectra,
the desirable wavelength transformers include those capable of
absorbing light at wavelengths lower than those suitable for curing
activatable composites and transforming them into longer
wavelengths useful for curing activatable composites. The desirable
absorber/emitter also includes those that emit a narrow spectrum or
a broader spectrum including wavelengths suitable, for example, for
activating both CQ and PPD in the composites. This embodiment of
the absorber/emitter may be used alone or in combination with the
embodiments described above. Combinations of this embodiment of
absorber/emitter may also be used.
[0098] Coating concentration of the dye, pigment, and/or
naocrystals may range from, for example, about 0.005 to about 5% by
weight, further for example, about 0.01 to about 1% by weight,
based on the weight of the substrate. As noted, they may also be
directly deposited coated or sputtered onto the emitting source or
some edges of the emitting source.
[0099] In a further embodiment, the wavelength transformer may also
include a prism.
[0100] The housing 101 may be made of any polymeric material,
including any polymer that may be molded or cast; or a metal or
metallic alloy. Suitable polymers include polyethylene,
polypropylene, polybutylene, polystyrene, polyester, acrylic
polymers, polyvinylchloride, polyamide, or polyetherimide like
ULTEM.RTM.; a polymeric alloy such as Xenoy.RTM. resin, which is a
composite of polycarbonate and polybutyleneterephthalate or
Lexan.RTM. plastic, which is a copolymer of polycarbonate and
isophthalate terephthalate resorcinol resin (all available from GE
Plastics), liquid crystal polymers, such as an aromatic polyester
or an aromatic polyester amide containing, as a constituent, at
least one compound selected from the group consisting of an
aromatic hydroxycarboxylic acid (such as hydroxybenzoate (rigid
monomer), hydroxynaphthoate (flexible monomer), an aromatic
hydroxyamine and an aromatic diamine, (exemplified in U.S. Pat.
Nos. 6,242,063, 6,274,242, 6,643,552 and 6,797,198, the contents of
which are incorporated herein by reference), polyesterimide
anhydrides with terminal anhydride group or lateral anhydrides
(exemplified in U.S. Pat. No. 6,730,377, the content of which is
incorporated herein by reference) or combinations thereof.
[0101] In addition, any polymeric composite such as engineering
prepregs or composites, which are polymers filled with pigments,
carbon particles, silica, glass fibers, conductive particles such
as metal particles or conductive polymers, or mixtures thereof may
also be used. For example, a blend of polycarbonate and ABS
(Acrylonitrile Butadiene Styrene) may be used for the housing
101a.
[0102] Generally, examples for the housing 101 include, for
example, polymeric materials or composites having high temperature
resistance.
[0103] Suitable metal or metallic alloys may include stainless
steel; aluminum; an alloy such as Ni/Ti alloy; any amorphous metals
including those available from Liquid Metal, Inc. or similar ones,
such as those described in U.S. Pat. No. 6,682,611, and U.S. Patent
Application No. 2004/0121283, the entire contents of which are
incorporated herein by reference.
[0104] A liquid crystal polymer or a cholesteric liquid crystal
polymer, one that can reflect rather than transmit light energy,
may be used, for example, as a coating in the interior 101 of the
light module housing 101, to minimize the waste of light energy
generated by the light source, as described, for example, in U.S.
Pat. Nos. 4,293,435, 5,332,522, 6,043,861, 6,046,791, 6,573,963,
and 6,836,314, the contents of which are incorporated herein by
reference.
[0105] Light emitted from the light source 130 having, for example,
LED 131 includes an emission spectrum including at least one
wavelength .lamda..sub.1 capable of initiating curing of a
composite. At least a portion of the light, for example, one half
of the light as shown in FIG. 3A, may be captured and transformed
into a longer wavelength, .lamda..sub.2, also capable of initiating
a chemical reaction to cure the dental composite material by at
least one wavelength transformer 140 situated in the direct path of
the light emitted by the LED 131, as shown in FIG. 3A. The
wavelength may be at an oblique angle to the longitudinal axis of
rotation of the light module, or any other angle that is most
efficient at capturing at least a portion of the light coming from
the light source 130.
[0106] FIG. 3C shows an exemplary light emitting diode 350
according to one embodiment of the invention. The diode 350
includes a first region of doped semiconductor material 352 of a
first "type." The diode 354 also includes a second region of doped
semiconductor material 354 on a second opposite "type." As would be
understood by one of skill of the art, the "type" of semiconductor
material is established during manufacturing of the diode 350 by
adding respective quantities of electron donor and/or acceptor
atoms. During operation of the diode, electrons and holes from the
first 352 and second 354 regions combine near a junction 356
between the first and second regions. The combination of electrons
and holes produces photons which are emitted, in the illustrated
embodiment, substantially coplanar with a plane of the junction
356. Accordingly, the photons generated at the junction 356 emerge
from the diode 350 through the four edges 360, 362, 364 and 366 of
the diode. According to one embodiment of the invention, edges 362
and 366 each may include a respective coating or film of
absorber/emitter material 368, 370. The absorber/emitter material
may be disposed such that light escaping from the edges 352, 366
passes through the respective absorber/emitter material 368, 370.
As is discussed above and will be discussed in additional detail
below, a portion of the light passing through the absorber/emitter
material 368, 370, may be absorbed by the absorber/emitter
material. This absorption process energizes electrons within the
absorber/emitter material and results in the emission of light of a
longer wavelength when the energized electrons return to their
respective lower energy states. Consequently, the absorber/emitter
material acts as a wavelength transformer with respect to some or
substantially all of the light being emitted through edges 362 and
366. Notably, light emitted through edges 360 and 364 that does not
pass through the absorber/emitter material 368, 370, and
consequently no wavelength transformation takes place with respect
to this light. As a result, a portion of the light produced by the
diode 350 has a wavelength within a first spectral distribution,
and a further portion of the light produced by the diode 350 has a
wavelength within a second, transformed, spectral distribution.
[0107] One of skill of the art will appreciate that the arrangement
of coated edges shown in diode 350 of FIG. 3C is only one of a wide
variety of possible configurations intended by the inventor to fall
within the scope of the invention. For example, one edge alone of
the diode, rather than the illustrated two edges, may include the
absorber/emitter material. In another embodiment, three of the four
edges may have the absorber/emitter material disposed thereupon. In
still another embodiment, the diode may include a different number
of edges, such as, for example 3 for a triangular diode, five for a
pentagonal diode, six for a hexagonal diode, and so on. In each
case, the particular number and arrangement of coated sides may be
selected according to the requirements of a particular
application.
[0108] In another embodiment, the absorber/emitter material may be
present as a bulk material or window, rather than a deposited or
absorbed film. In still another embodiment, more than one
absorber/emitter material may be disposed on respective edges of a
diode, so as to produce a particularly desired spectral
distribution of light.
[0109] Still other embodiments of the invention may include an
absorber/emitter material that is disposed on a diode edge with a
particular geometric pattern or random distribution, such that
light of both transformed and un-transformed wavelengths is emitted
from that edge.
[0110] FIG. 4 depicts another embodiment of the present invention
including a beam splitter 150 positioned in the direct path of the
light emitted by the light source 130 to split the beam into two
beams. Positioned in the path of one of the beams includes at least
one wavelength transformer 140 capable of capturing substantially
all of the light and transforming it into a longer wavelength
.lamda..sub.3. The wavelength transformer may be positioned in the
direct path of the beam of light coming from the beam splitter, as
shown here.
[0111] In addition, more than one wavelength transformers may be
used, as shown in FIG. 5. In FIG. 5, wavelength transformers 141
and 142 are positioned at oblique angles to the light path of the
light source 130 so as to capture any light not captured by the
beam splitter 150 or the other wavelength transformer 140. These
other wavelength transformers, 141 and 142 may be of the same type
as 140 or of a type that transforms only a part of the emitted
wavelength.
[0112] Additionally, as shown in FIG. 6, at least one reflector 160
may be positioned about the mounting 121 for the LED 131. In this
embodiment, the reflector is conical and may include a surface
adapted to reflect and direct substantially all stray light emitted
by the LED 131 towards the proximal end 112 of the handle 102. At
least one wavelength transformer 140 is positioned in the path of
the light coming both from the LED and the reflector 160, as shown
in FIG. 7.
[0113] In another embodiment, the walls of a curved heat sink, as
shown in FIG. 15, may also act as a reflector.
[0114] In other embodiments, the inside surface 101a of the light
module housing 101 may include reflecting surfaces, adapted also
for reflecting and directing substantially all stray light emitted
by the LED 131 towards the proximal end 112 of the light module
housing 101. At least one wavelength transformer 140 is positioned
in the path of the light coming both from the LED and the
reflector.
[0115] The reflector mayn include an opening through which light
passes through.
[0116] In one aspect, the reflecting surface is present towards the
proximal end 112, near the head and neck portion 103 of the housing
101. In another aspect, the reflecting surface may be present in
substantially most of the interior of the proximal end 112 of the
light module housing.
[0117] The reflecting surface of the reflector 160, the curved
walls of a heat sink 120, or the interior 101a includes, for
example, a reflective metal, a highly polished metal, or a
non-specular paint. A reflective metal, for example, a metal having
a reflectivity greater than 90% may improve the yield of light
collected by the curing light by, may be 50%. Examples of suitable
metals include silver, aluminum, rhodium, gold or combinations
thereof. The reflective metal may also be selected based on, for
example, the substrate the reflective layer is to be deposited, or
the wavelength of the light it is to reflect. For example, it is
known that gold is highly reflective of light in the red or
infra-red wavelength ranges.
[0118] Other embodiments of the reflecting surfaces include
anodized aluminum, and surfaces formed by vapor deposition of
dielectric layers onto metallic layers, or polymeric layers, for
example, a metallic layer on an anodized surface as the base
reflection layer, followed by deposition of a low refractive index
and then a high refractive index dielectric layer, such as those
available from Alanod, Ltd. of the United Kingdom.
[0119] In addition, the reflector 160 may also include a liquid
crystal polymer, one that reflects rather than transmits light
energy, either as a surface coating for the reflecting surface or
as a main ingredient of the reflector 150. The liquid crystal
polymer may include that as described, for example, in U.S. Pat.
Nos. 4,293,435; 5,332,522; 6,043,861; 6,046,791; 6,573,963; and
6,836,314, or other materials with similar properties. Also, a
reflector usable in the present invention includes various
reflectors having various different configurations, and may, for
example, be of a parabolic one, capable of directing the light
emitted by the LED towards the proximal end of the handle.
[0120] At least one reflector 160 may also be integral to the light
source, either formed on or attached to it. This reflector 160 may
also be, for example, of a parabolic shape, again capable of
directing the light emitted by the LED towards the proximal end of
handle.
[0121] In FIG. 7, light emitted from the LED 131 includes an
emission spectrum having at least one wavelength capable of
initiating curing of a composite. A device situated in the light
path of the emitting LED includes at least one wavelength
transformer 140 for transforming at least a portion of the light
emitted by the LED 131 into a longer wavelength, which is also
capable of initiating a chemical reaction to cure the dental
composite material, and at least one reflector capable of
reflecting substantially all light in its path towards the
wavelength transformer. The light in the path of the reflector may
be substantially all of the light or a portion of the light emitted
by the light source 130, or it may also be either all or a portion
of the light coming from the beam splitter (not shown in FIG. 7).
As is discussed above, more than one wavelength transformer and/or
more than one reflector may be present in the light path.
[0122] Thus, the beneficial properties of the wavelength
transformers of the present invention, either including organic or
inorganic dyes, pigments, semiconductor nanocrystals as disclosed
above, or combinations thereof, capable of emitting narrower
spectra; capable of absorbing wavelength lower than those suitable
for activating curable composites and emitting a broader spectrum
including wavelengths useful for curing composites; capable of
absorbing wavelength shorter than those suitable for activating
curable composites and emitting a narrow spectrum including a
longer wavelength useful for curing composites; or combinations
thereof; may go to alleviate thermal management problems present in
the confined space of a portable curing light device.
[0123] Use of a light transport device such as a light guide 170,
as shown in FIG. 8, may be a means of keeping heat away from the
target surface and its surroundings, such as a patient's mouth, and
may also help in terms of run time and thermal management of the
system. The light guide may help to diffuse, rather than
concentrate the point of heat generation. The light guide 170 may
be of an elongated shape, as shown, and may be in the form of a
substantially hollow tube, pipe or an optically conductive cable,
having a distal end 171, attached to the proximal end 112 of the
light module housing 101, and a proximal end 172 having a cover
173. The cover 173 may be include a focusing dome, or lens 174 for
focusing the light towards the target surface, as shown in FIG. 10.
The cover, in an alternative embodiment, may include a tip, such as
a tacking tip 175, as shown in FIG. 11, for molding, shaping or
compacting the curable composite. The focusing dome or lens 174 may
also act as a means for varying the size of the light beam exiting
the proximal end 112 of the handle 102, in order to more correctly
directing the beam of light, either at a small target area or over
a wider target area. The varying diameter feature may be
accomplished by means of different focusing domes or lens, or a
dome or lens may have an adjusting mechanism to vary the beam
diameter.
[0124] In another embodiment, the light guide 170 may be the head
and neck portion 103 of the housing, as described above.
[0125] In yet another embodiment, the light guide may be a device
for aiding the positioning of the curing light, and an example of
such a light guide is shown in FIG. 9A. The light guide includes a
distal end 171 having at least one formation, adapted to be coupled
to a light source 130, having a formation, for example, a support
structure at the proximal end 112 of the housing 101, and a
proximal end 172 having at least one formation adapted to be
coupled, additionally or in turn, to a lip retracting device 500,
as shown in FIG. 9B, which is adapted to draw the soft tissue of
the lips away from the teeth of a subject patient so as to provide
an unobstructed path between the proximal end of the light guide
and a tooth surface of the subject patient. The lip retracting
device includes at least one formation, for example, a wing-like
member, adapted for coupling it to the at least one formation of
the light guide. The lip retracting device is described in U.S.
Patent Application No. 60/641,461, the contents of which are
incorporated herein by reference.
[0126] The light guide 170 as shown, includes an elliptically
tubular member having an axial cavity 179 disposed between a front
aperture 176 and a rear aperture 178. As shown in the illustrated
embodiment, a first edge 181 of the tubular member defines a
substantially elliptically saddle shaped curve having a convex form
in relation to a generally horizontal portion 180 thereof and a
concave form in relation to a generally vertical portion 182
thereof. In addition, edge 181 includes first and second
substantially horizontal slots 184, 186. According to one
embodiment of the invention, the slots 184, 186 are disposed
substantially coplanar with respect to one another and are disposed
substantially coincident with a major axis of the elliptically
saddle shaped curve that defines edge 181.
[0127] As shown in the illustrated embodiment, a rim 188 extends
radially inwardly from the edge 181 to a second substantially
elliptically saddle shaped curved edge 190 (also referred to as the
"second edge"). The second edge 190 is disposed in substantially
constantly space relation to edge 181, whereby the rim 118 has a
substantially uniform radial dimension over the length of edge 181.
Edge 190 defines an outer periphery of the front aperture 186.
[0128] At the rear end of the embodiment of FIG. 9A, a third edge
200 defines another curve that is of an approximately elliptically
saddle shape. Edge 200 may be substantially concave in form in
relation to a generally horizontal portion 132 thereof and is
generally convex in form in relation to a generally vertical
portion 234 thereof. The detailed description of the light guide is
found in U.S. Provisional Patent Applications No. 60/641,468 and
60/647,580; Co-pending U.S. patent application entitled "Light
Guide for Dentistry Applications", to be filed concurrently with
this case, and U.S. Design Patent Application No. 29/220,680
incorporated herein by reference in their entirety.
[0129] The light guide 170 may be made of similar material as that
of the light module housing 102 as described above. Also,
biodegradable or biocompostable polyesters such as a polylactic
acid resin (comprising L-lactic acid and D-lactic acid) and
polyglycolic acid (PGA); polyhydroxyvalerate/hydroxybutyrate resin
(PHBV) (copolymer of 3-hydroxy butyric acid and 3-hydroxy pentanoic
acid (3-hydroxy valeric acid) and polyhydroxyalkanoate (PHA)
copolymers; and polyester/urethane resin are also suitable,
especially if single-use.
[0130] Additionally, like the light module housing 101, a
cholesteric liquid crystal polymer, one that reflects rather than
transmits light energy, may be used, either as a coating or as the
main ingredient of the light guide to minimize escape of light
energy, as described, above, for example.
[0131] Also, the structure of the light guide, for example, may
include a UV-inhibiting material in order to protect the patient's
skin from ultra-violet light exposure.
[0132] The handle 102 of the curing light may be fitted with a hand
grip device 300 having coupling pin 301, for coupling the curing
light to the light guide 170, as shown in FIG. 12.
[0133] The handle 102 may also be adapted to rest on the horizontal
portion of the light guide structure 170 during use, to help to
support the curing light. For example, as shown in FIG. 9B, the
light guide 170 may be coupled to a lip retracting device 500 by
coupling together the respective slots 186 of the light guide and
wings 502 of the lip retracting device 500. According to one
embodiment, the light guide 170 includes a pedestal 504 disposed
therein. The pedestal may have, according to an exemplary
embodiment, an upper surface 506 with a vertical bore 508. In one
embodiment, the vertical bore 508 may be adapted to receive a
coupling pin 301 (as illustrated in FIG. 12). This arrangement
allows the ready coupling and decoupling of the curing light and
light guide, when the light guide is used to support the curing
light.
[0134] FIG. 9c shows another embodiment of the invention in which
the curing light is merely rested on the upper surface 506 of the
pedestal 504 within the light guide 170.
[0135] The positioning light guide may help to fix the position
between the light source and the target area, so that any
accidental movement by the operator does not also result in the
curing light being pointed in an undesirable location, leading to
potential tissue damage.
[0136] The heat sink 120 may also play a big part in thermal
management in the present invention. In the embodiment depicted in
FIG. 13, multiple LEDs or LED arrays 131 may be mounted on the
mounting platforms 121 of one heat sink 120. FIG. 13 shows the
emitted light passing through at least one wavelength transformer
and being collected by a reflecting apparatus and focused by a
lens.
[0137] In another embodiment of the invention, as is shown in FIG.
14A, each of the LEDs or LED arrays 131 may be formed on or
attached to a primary heat sink 120a which may be mounted to the
mounting platform 121 on a secondary heat sink, such as an
elongated heat sink 120. The primary heat sinks 120a are smaller in
overall volume than the secondary heat sink 120. In another aspect,
no secondary heat sink is present. In yet another aspect, the
secondary heat sink may be an air gap, an air jacket, a fan or
combinations thereof as exemplified, for example, by the embodiment
of FIG. 14B.
[0138] FIG. 14B shows, in cross section, a portion 400 of a curing
light according to one embodiment of the invention. The curing
light includes a light source 401 including an array of light
emitting diodes 402 disposed on a substrate 404. The light source
is supported on a proximal surface of a heat sink 406. An electric
motor 410 is coupled to, and supported by, a distal surface of the
heat sink 406. The motor 410 includes a motor housing 412 and a
rotatable shaft 414.
[0139] Rotatable shaft 414 may be substantially fixedly coupled to
a fan 416, such as a centrifugal or vane-axial fan, such that
operation of the motor 410 causes rotation of the fan 416.
[0140] During operation of the curing light 400, the motor 410 is
operated to cause rotation of the fan 416. The motor 410 may be
operated intermittently, cyclically, or continuously, according to
the design of a particular embodiment of the invention. As the fan
416 is rotated, air is ejected from the fan blades or vanes through
one or more exhaust ports 420 disposed in the housing of the curing
light 400. As air is ejected from the exhaust ports 420, ambient
air pressure causes a flow of external cooling air inwardly through
one or more intake ports 422. The cooling air flows more or less
axially past the light source 401 and past one or more surfaces of
the heat sink 406. According to the illustrated embodiment, the
cooling air also flows past one or more surfaces of the housing 412
of the motor 410, such that the light source 401, the heat sink 406
and the motor 410, each gives up excess heat to the cooling air. In
this way, the light source 401 and motor 410 are maintained within
respective specified operating temperature ranges.
[0141] another embodiment of the invention, the at least one LED
located in the mounting platform located towards the proximal end
112 of the housing 101 may have a reflector formed on or attached
to it, as discussed before. The reflector is, for example, a
parabolic one, capable of directing the light emitted by the LED
towards the proximal end 112 of the housing 101.
[0142] As shown in FIGS. 13 and 14, the light emitted by the LEDs
or LED array 131 passes through at least one wavelength transformer
140 which may be then collected by a reflector apparatus 160 and
focused by a focusing means 165.
[0143] The reflector apparatus includes at least one reflector 160
which may be in any of the shapes described above, for example, a
parabolic one, adapted for reflecting light towards the proximal
end 112 of the handle 101.
[0144] The focusing means 165 may be fixed or removable and may be
located towards the proximal end of the light module housing 101
and may include a focusing lens for focusing the light towards the
target surface. The focusing means may also be a cover 173 which
may include a focusing dome, or lens 174. The cover may also
include a tip, such as a tacking tip 175, for molding, shaping or
compacting the curable composite. The tacking tip may be a
removable attachment. The focusing dome or lens 174 may also act as
a means for varying the size of the light beam exiting the proximal
end 112 of the handle 102, in order to more correctly directing the
beam of light, either at a small target area or over a wider target
area, as noted before.
[0145] As noted, the heat sink may be an elongated heat sink, but
it may also be of any other shape. The primary heat sinks, if
present, may be attached to the LEDs, either by integral forming
such as molding, or by attachment means, such as an adhesive. The
mounting platform 121 may include a well in the surface of the heat
sink which may also act as a reflecting surface.
[0146] A heat sink 120 may also include a deep well, as shown in
FIG. 15a, which depicts a cross-sectional view. In this embodiment,
the elongated heat sink 120 has a deep well having side walls with
the proximal end 120a being at the top of the well and the distal
end 120b at the bottom of the well. At least two mounting platforms
121 may be located towards the proximal end 120a, and at least one
mounting platform 121 may be located towards the distal end 120b of
the elongated heat sink. On each of the mounting platforms 121 may
be mounted at least one LED 131. The LED 131 may be capable of
emitting same or different wavelengths. This curing light
construction may be capable of more effective heat dissipation by
not concentrating the heat product at one location.
[0147] At the distal end 120b, there may be a smaller primary heat
sink 150 or an LED having a smaller primary heat sink 150 mounted
thereon. The smaller primary heat sink may also comprise a well,
which may also act as a reflector if it includes a reflecting
surface, to reflect all stray light towards the target area.
[0148] The elongated heat sink 120 as shown may also have a planar
mounting platform 121 on its distal end (not shown) for mounting
light sources such as LEDs or arrays 131, or the platform may
include a reflector. Though the heat sink 120 is shown as an
elongated shape, it may also be of other shapes, as desired, for
rapid heat dissipation or transfer away from the light sources.
[0149] Heat management is important, especially for a compact
and/or hand held curing light. If heat transfer and dissipation are
not handled adequately, damage to the LEDs or LED arrays 131 may
result, or light output of the LEDs or LED arrays may be diminished
or compromised.
[0150] Different geometric shapes facilitate the arrangements of
the light sources for improved runtime efficiency. This along with
higher efficiency heat sinks may lead to a better curing light.
[0151] In one embodiment, the light module housing 101 may be
separated from the heat sink 120 by a buffer layer or an insulating
means 163. The heat sink 120 may occupy less than about 50%, less
than about 60% of the length of the light module housing 101.
Electrically conductive wires 164 are also provided to power the
light sources such as the LEDs or LED arrays 131. A buffer layer or
an insulation means 163 is there to separate the heat sink 120 from
the housing 101 to facilitate heat dissipation, and may be in the
form of an insulation tape, an air space, an air jacket, or any
material that will provide spacing and distance between the heat
sink 120 and the light module housing 101 to form an air jacket in
between to permit air circulation, ventilation and heat
dissipation. The insulation means may also include rubbers,
silicones, plastics or other materials.
[0152] The housing 101 may also have one or more vents or holes
161a to permit or encourage air to travel from outside the casing
161 into the air jacket 163, and/or to permit or encourage air from
the air jacket 163 to travel outside of the housing 161. This air
exchange mat assist in cooling the light module 101, especially
during the resting or recharging cycle of the device. The air
jacket 163 may thus assist in avoiding a buildup of heat in the
device that could result in short run time or even cause user
discomfort.
[0153] As an exemplary embodiment of the heat sink 120, FIG. 15
shows the heat sink as an elongated heat sink having a curved
structure for positioning an LED or array 131 at its proximal end
120b. There may be a smaller primary heat sink 120' or an LED
having a smaller primary heat sink 120' mounted thereon.
[0154] As another exemplary embodiment, the elongated heat sink 120
as shown in FIG. 16 may have a planar mounting platform 121 on its
proximal end 120b for mounting a light source such as LEDs or
arrays 131. In addition, the LED or LED array 131 may be covered by
a protective cover, dome or a focus lens 139. In one embodiment,
the protective cover, dome or focus lens may also include a
wavelength transformer 140. This may potentially improve the
efficiency of the system and decrease the amount of heat needed to
be diverted or conducted away from the light sources 130.
[0155] Though the heat sink 120 is shown as an elongated shape, it
may also be of other shapes, as desired, for rapid heat dissipation
or transfer away from the LEDs or arrays 131.
[0156] The heat sink may be made of any material that has good
thermal conductivity, including metal blocks of copper, aluminum or
similar. In another embodiment, the cooling system includes heat
pipes. In another embodiment, the cooling system includes phase
change materials, some embodiments and material are exemplified as
is described in U.S. Application No. 60/585,224, "Dental Light
Devices With Phase Change Material Filled Heat Sink", filed on Jul.
2, 2004, the contents of which are incorporated herein by
reference.
[0157] For example, the heat sink may include a block of thermally
conductive material such as a metal having a bore or void space
which is at least partially filled with a phase change
material.
[0158] The heat sink may includes a material that can more
efficiently remove or divert heat from a curing light device when a
reduced weight of heat sink material is used for better
portability.
[0159] In one embodiment, the heat sink may include a phase change
material that is more efficient in removing or diverting heat from
a light source or sources with a given weight of heat sink material
when compare to a heat sink made of a solid block of thermally
conductive material such as metal.
[0160] In another embodiment, the heat sink may include at least
one suitable phase change material including organic materials,
inorganic materials and combinations thereof. These materials can
undergo substantially reversible phase changes, and can typically
go through a large, if not an infinite number of cycles without
losing their effectiveness.
[0161] In other embodiments, the heat sink may include compressed
air cartridges which may be easily installed and replaced. The
housing may be constructed with a support platform, similar to that
for mounting a battery pack, for mounting cartridges. The
cartridges may contain sufficient cooling for each cycle or
multiple cycles.
[0162] As another example, the heat sink maybe of a thermoelectric
cooling type, also called "the Peltier Effect," which is a
solid-state method of heat transfer through dissimilar
semiconductor materials. The semiconductor materials are N and P
types, with the N-type having more electrons than necessary to
complete a perfect molecular lattice structure, and the P-type not
having enough electrons to complete a lattice structure. The extra
electrons in the N-type material and the holes left in the P-type
material are called "carriers" and they are the agents that move
the heat energy from the cold to the hot junction. Heat absorbed at
the cold junction is pumped to the hot junction at a rate
proportional to carrier current passing through the circuit and the
number of couples.
[0163] The cold junction or evaporator surface becomes cold through
absorption of energy by the electrons as they pass from one
semiconductor to other semiconductor material or materials with
dissimilar characteristics which are connected electrically in
series and thermally in parallel, so that two junctions are
created.
[0164] Good thermoelectric semiconductor materials such as bismuth
telluride greatly impede conventional heat conduction from hot to
cold areas, yet provide an easy flow for the carriers. In addition,
these materials have carriers with a capacity for transferring more
heat.
[0165] For a thermoelectric type heat sink, heat maybe transferred
by the usual modes of conduction, convection, and radiation.
[0166] The heat sink may be constructed, for example, by hollowing
out a thermally conductive material, such as metal, and at least
partially filling the void with at least one phase change material
prior to capping it to secure the phase change material inside,
such that the at least one phase change material is substantially
contained or surrounded by a thermally conductive material such as
metal normally used in the construction of a conventional metal
heat sink.
[0167] As another example, the heat sink may be cast or machined
out of a thermally conductive material such as metal walls
surrounding a bore or void. The bore or void is partially filled
with at least one phase change material prior to capping it to
secure the material inside. If desired, a heat sink may also have
fins or other outer surface modifications or structures to increase
surface area and enhance heat dissipation.
[0168] Other or additional features may also be included in the
curing light of the present invention. For example, FIG. 17 shows a
perspective view of a curing device. A switch 108a is provided on
the top of the housing 101, while a second switch 108b is provided
on the side of the housing 101. These switches 108a and 108b are
means for turning the light emission of the light on and off and
may take the form of such as a button or trigger. A timer 109
(including, for example, increment 550 and decrement 552 buttons
and a miniature time remaining display 554) may also be provided to
control the duration of time that the light is on. Other control
buttons such as to set and adjust the timer (not shown) can also be
present on the handle.
[0169] An audible indicator or beeper may be provided in some
lights to indicate when light emission from the light module begins
and ends. In one embodiment, this may be a voice alert system,
verbally relating the stage and progress of the operation. In
another embodiment, this may be a voice alert system, verbally
relating the stage and progress of the operation as well as an auto
shut off of the light source at the end of the cycle.
[0170] An indicator 210 for indicating low battery power may be
located on the housing 101 in a location that is easily visible to
the dental professional during use concerning the status of the
battery power of the battery powered curing light, as shown in FIG.
17. A second indicator 210a may also be located on the housing in a
visible location in order to indicate to the user that the battery
is being charged. These indicators may also be LEDs.
[0171] There is also a main on/off switch 230 provided at the rear
or proximal end 112 of the housing 101. An optional wavelength
selector (not shown) may also be provided in some curing lights so
that the dental professional may select the wavelength of light
that he/she wishes to emit from the light, depending on the
wavelength sensitivity of the photoinitiator in the light-activated
material that he is using. The user may also select a combination
of two or more wavelengths of light to be emitted together in some
lights.
[0172] A separate battery charger module 220 may be included in
order to receive AC power from a traditional wall socket and
provide DC power to the light system for both charging the
batteries and powering the light source and control circuitry when
the batteries if desired, as shown in FIG. 18. The battery charger
module 221 has a cable 221a and a plug 221b for plugging into a
receptacle or connector 222 on the distal end 111 of the light
module housing 101. The battery charger module 221 includes
circuitry 221c for controlling battery charging of batteries (not
shown).
[0173] The battery charger may also have a built in heat
dissipation means for drawing heat away from the curing light while
the battery is being charge or simply while the curing light is
being rested between use cycles. In one embodiment, the heat
dissipation means may include a fan. In another embodiment, the
heat dissipation means may include compressed air.
[0174] Having described the invention by the description and
illustrations above, it should be understood that these are
exemplary of the invention and are not to be considered as
limiting. Accordingly, the invention is not to be considered as
limited by the foregoing description, but includes any
equivalents.
* * * * *