U.S. patent application number 11/245960 was filed with the patent office on 2006-02-02 for reduced area imaging device incorporated within wireless endoscopic devices.
Invention is credited to Edwin L. Adair, Jeffrey L. Adair, Randall S. Adair.
Application Number | 20060022234 11/245960 |
Document ID | / |
Family ID | 27497150 |
Filed Date | 2006-02-02 |
United States Patent
Application |
20060022234 |
Kind Code |
A1 |
Adair; Edwin L. ; et
al. |
February 2, 2006 |
Reduced area imaging device incorporated within wireless endoscopic
devices
Abstract
A reduced area imaging device is provided for use in medical or
dental instruments such as an endoscope. In a first embodiment of
the endoscope, connections between imaging device elements and
between a video display is achieved by hard-wired connections. In a
second embodiment of the endoscope, wireless transmission is used
for communications between imaging device components, and/or for
transferring video ready signals to a video display. In one
configuration of the imaging device, the image sensor is placed
remote from the remaining circuitry. In another configuration, all
of the circuitry to include the image sensor is placed in a stacked
fashion at the same location. The entire imaging device can be
placed at the distal tip of an endoscope. Alternatively, the image
sensor can be placed remote from the remaining circuitry according
to the first configuration, and control box is used which
communicates with the image sensor and is placed remotely from the
endoscope. Further alternatively, the imaging device can be
incorporated in the housing of a standard medical camera which is
adapted for use with traditional rod lens endoscopes. In any of the
configurations or arrangements, the image sensor may be placed
alone on a first circuit board, or timing and control circuits may
be included on the first circuit board containing the image sensor.
The timing and control circuits and one or more video processing
boards can be placed adjacent the image sensor in a tubular portion
of the endoscope, in other areas within the endoscope, in the
control box, or in combinations of these location.
Inventors: |
Adair; Edwin L.; (Castle
Pines Village, CO) ; Adair; Jeffrey L.; (Highlands
Ranch, CO) ; Adair; Randall S.; (Denver, CO) |
Correspondence
Address: |
SHERIDAN ROSS PC
1560 BROADWAY
SUITE 1200
DENVER
CO
80202
US
|
Family ID: |
27497150 |
Appl. No.: |
11/245960 |
Filed: |
October 6, 2005 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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09929531 |
Aug 13, 2001 |
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11245960 |
Oct 6, 2005 |
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09496312 |
Feb 1, 2000 |
6275255 |
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09929531 |
Aug 13, 2001 |
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09175685 |
Oct 20, 1998 |
6043839 |
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09496312 |
Feb 1, 2000 |
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08944322 |
Oct 6, 1997 |
5929901 |
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09175685 |
Oct 20, 1998 |
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09368246 |
Aug 3, 1999 |
6310642 |
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11245960 |
Oct 6, 2005 |
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Current U.S.
Class: |
257/292 ;
348/E5.043 |
Current CPC
Class: |
A61B 1/00135 20130101;
H01L 25/167 20130101; H01L 2924/0002 20130101; H01L 2924/0002
20130101; H01L 2924/00 20130101; A61B 1/0051 20130101; H04N 5/2253
20130101; H01L 2924/3011 20130101; A61B 1/00016 20130101; A61B
1/0607 20130101; H04N 7/142 20130101; A61B 1/07 20130101; H04N
2005/2255 20130101; H04N 5/23203 20130101; A61B 1/05 20130101 |
Class at
Publication: |
257/292 |
International
Class: |
H01L 31/113 20060101
H01L031/113 |
Claims
1.-45. (canceled)
46. A wireless endoscope for wirelessly transmitting image signals,
said endoscope comprising: a tubular portion including a distal
end, a proximal end and a central passageway extending
therethrough; an image sensor positioned in said tubular portion
for receiving images of a surgical site, said image sensor
producing an image signal; timing and control circuitry
electrically coupled to said image sensor; video processing
circuitry electrically coupled to said image sensor for processing
said image signal and converting said image signal to a post-video
signal; a radio transceiver element mounted in said endoscope and
electrically coupled to said video processing circuitry for
wirelessly transmitting the post-video signal; and a radio
transceiver module placed remote from said endoscope for receiving
said post-video signal and for electrically transferring said post
video signal to a video display for viewing video images.
47. A device, as claimed in claim 46, wherein: said wireless
transmitting by said radio transceiver element is conducted by a
Bluetooth communications standard.
48. A device, as claimed in claim 46, wherein: said wireless
transmitting by said radio transceiver element is conducted by an
IEEE 802.15.13 communications standard.
49. A device, as claimed in claim 46, wherein: said image sensor
further includes a pixel array of CMOS pixels incorporated in said
image sensor for receiving images thereon.
50. A device, as claimed in claim 46, wherein: said timing and
control circuitry is placed adjacent said image sensor in said
tubular portion.
51. A device, as claimed in claim 46, wherein: said timing and
control circuitry is placed on a plane along with said image
sensor.
52. A device, as claimed in claim 46, further including: a handle
attached to said tubular portion; and wherein said timing and
control circuitry is placed in said handle.
53. A device, as claimed in claim 46, wherein: said video
processing circuitry is placed adjacent said image sensor in said
tubular portion.
54. A device, as claimed in claim 46, wherein: said video
processing circuitry is placed adjacent said image sensor in said
tubular portion and longitudinally aligned with said image
sensor.
55. A device, as claimed in claim 46, further including: a handle
attached to said tubular position; and said video processing
circuitry is placed in said handle.
56. A device, as claimed in claim 46, wherein: said image sensor is
placed on a first plane, and said circuitry means for timing and
control and said video processing means are placed on a second
plane.
57. A device, as claimed in claim 56, wherein: said second plane is
longitudinally aligned with said first plane in said tubular
portion.
58. A device, as claimed in claim 46, further including:
supplementary circuitry electrically coupled to said image sensor
for enhancing said pre-video signal prior to reception by said
video processing circuitry.
59. A device, as claimed in claim 46, further including: at least
one light fiber positioned around a periphery of said distal end
for illuminating a surgical site.
60. A device, as claimed in claim 46, further including: a source
of light mounted in said endoscope; and at least one light fiber
communicating with said source of light and positioned in said
tubular portion for illuminating a surgical site.
61. A device, as claimed in claim 46, further including: a power
source including a rechargeable battery mounted in said
endoscope.
62. A device, as claimed in claim 1, further including: a power
source electrically coupled to said endoscope for powering the
endoscope wherein, said power source and said radio transceiver are
mounted a common housing which is removable with respect to said
endoscope for selective recharge or replacement of said power
source and for selective replacement of said radio transceiver
element.
63. A wireless endoscope for wirelessly transmitting image signals,
said endoscope comprising: a tubular portion including a distal
end, a proximal end and a central passageway extending there
through; an image sensor positioned in said tubular portion for
receiving images of a surgical site, said image sensor producing a
pre-video signal; timing and control circuitry electrically coupled
to said image sensor; a radio transceiver element mounted in said
endoscope and electrically coupled to said image sensor for
wirelessly transmitting the pre-video signal; a control placed
remote from said endoscope, said control including a radio
transceiver module for receiving said pre-video signal and for
electrically transferring said pre-video signal for further
processing; and video processing circuitry mounted in said control
and electrically coupled to said radio transceiver for processing
said pre-video signal and converting said pre-video signal to a
post-video signal, said video processing circuitry communicating
with a video display for viewing video images.
64. A device, as claimed in claim 63, wherein: said wireless
transmitting by said radio transceiver element is conducted by a
Bluetooth communications standard.
65. A device, as claimed in claim 63, wherein: said wireless
transmitting by said radio transceiver element is conducted by an
IEEE 802.15.13 communications standard.
66. A device, as claimed in claim 63, wherein: said control
communicates with said video display by a wired connection.
67. A device, as claimed in claim 63, wherein: said control
wirelessly communicates with said video display by a secondary
wireless transmission means.
68. A device, as claimed in claim 67, wherein: said secondary
wireless transmission means includes a secondary wireless
transmitter mounted in said control and electrically communicating
with said video processing means for wirelessly transmitting the
post video signal, and a secondary wireless receiver placed remote
from said control for receiving the post video signal, and
electrically transferring the post video signal directly to the
video display.
69. A device, as claimed in claim 63, wherein: said image sensor
further includes a pixel array of CMOS pixels incorporated in said
image sensor for receiving images thereon.
70. A device, as claimed in claim 63, wherein: said timing and
control circuitry is placed adjacent said image sensor in said
tubular portion.
71. A device, as claimed in claim 63, wherein: said timing and
control circuitry is placed on a plane along with said image
sensor.
72. A device, as claimed in claim 63, further including: a handle
attached to said tubular portion; and said timing and control
circuitry is placed in said handle.
73. A device, as claimed in claim 63, wherein: said image sensor is
placed on a first plane, and said timing and control circuitry is
placed on a second plane.
74. A device, as claimed in claim 73, wherein: said second plane is
longitudinally aligned with said first plane in said tubular
portion.
75. A device, as claimed in claim 63, further including:
supplementary circuitry electrically coupled to said image sensor
for enhancing said pre-video signal prior to reception by said
video processing circuitry.
76. A device, as claimed in claim 63, further including: at least
one light fiber positioned around a periphery of said distal end
for illuminating a surgical site.
77. A device, as claimed in claim 63, further including: a source
of light mounted in said endoscope; and at least one light fiber
communicating with said source of light and positioned in said
tubular portion for illuminating a surgical site.
78. A device, as claimed in claim 63, further including: a power
source mounted in said endoscope, said power source including a
rechargeable battery.
79. A device, as claimed in claim 63, wherein: a power source
mounted in said endoscope, said power source including a removable
and rechargeable battery, said battery adapted for recharge with a
remote charging circuit.
80. A device, as claimed in claim 63, further including: a power
source; and wherein, said power source and said radio transceiver
are mounted a common housing which is removable with respect to
said endoscope for selective recharge or replacement of said power
source and for selective replacement of said radio transceiver
element.
81. A wireless endoscope for wirelessly transmitting image signals,
said endoscope comprising: a tubular portion including a distal
end, a proximal end and a central passageway extending there
through; an image sensor positioned in said tubular portion for
receiving images of a surgical site, said image sensor producing a
pre-video signal; a radio transceiver element mounted in said
endoscope and electrically coupled to said image sensor for
wirelessly transmitting the pre-video signal; a control placed
remote from said endoscope, said control including a radio
transceiver module for receiving said pre-video signal and for
electrically transferring said pre-video signal for further
processing; timing and control circuitry mounted in said control
and electrically coupled to said radio transceiver module for
producing control signals to control functioning of said image
sensor, said radio transceiver module wirelessly transmitting said
control signals to said radio transceiver element and said radio
transceiver element receiving said control signals and transferring
the control signals to the image sensor; and video processing
circuitry mounted in said control and electrically coupled to said
radio transceiver module for processing said pre-video signal and
converting said pre-video signal to a post-video signal, said video
processing circuitry communicating with a video display for viewing
video images.
82. A device, as claimed in claim 81, wherein: said wireless
transmitting between said radio transceiver element and said radio
transceiver module is conducted by a Bluetooth communications
standard.
83. A device, as claimed in claim 81, wherein: said wireless
transmitting between said radio transceiver element and said
transceiver radio module is conducted by an IEEE 802.15.13
communications standard.
84. A device, as claimed in claim 81, wherein: said control
communicates with said video display by a wired connection.
85. A device, as claimed in claim 81, wherein: said control
wirelessly communicates with said video display by a secondary
wireless transmission.
86. A device, as claimed in claim 81, wherein: said secondary
wireless transmission includes a secondary wireless transmitter
mounted in said control and electrically communicating with said
video processing means for wirelessly transmitting the post video
signal, and a secondary wireless receiver placed remote from said
control for receiving the post video signal, and electrically
transferring the post video signal directly to the video
display.
87. A device, as claimed in claim 81, wherein: said image sensor
further includes a pixel array of CMOS pixels incorporated in said
image sensor for receiving images thereon.
Description
[0001] This application is a continuation-in-part of U.S. Ser. No.
09/496,312 filed on Feb. 1, 2000, and entitled "Reduced Area
Imaging Devices", which is a continuation of U.S. Ser. No.
09/175,685 filed Oct. 20, 1998 entitled "Reduced Area Imaging
Devices", now U.S. Pat. No. 6,043,839, which is a
continuation-in-part of U.S. Ser. No. 08/944,322, filed Oct. 6,
1997, and entitled "Reduced Area Imaging Devices Incorporated
Within Surgical Instruments", now U.S. Pat. No. 5,929,901. This
application is also a continuation-in-part of U.S. Ser. No.
09/368,246 filed on Aug. 3, 1999, and entitled "Reduced Area
Imaging Devices Incorporated Within Surgical Instruments".
TECHNICAL FIELD
[0002] This invention relates to solid state image sensors
incorporated within wireless endoscopes, and more particularly, to
solid state image sensors which are incorporated within wireless
endoscopes that wirelessly transmit video images for viewing.
BACKGROUND ART
[0003] In recent years, endoscopic surgery has become the accepted
standard for conducting many types of surgical procedures, both in
the medical and dental arenas. The availability of imaging devices
enabling a surgeon or dentist to view a particular surgical area
through a small diameter endoscope which is introduced into small
cavities or openings in the body results in much less patient
trauma as well as many other advantages.
[0004] In many hospitals, the rod lens endoscope is still used in
endoscopic surgery. The rod lens endoscope includes a very precise
group of lenses in an elongate and rigid tube which are able to
accurately transmit an image to a remote camera in line with the
lens group. The rod lens endoscope, because of its cost of
manufacture, failure rate, and requirement to be housed within a
rigid and straight housing, is being increasingly replaced by solid
state imaging technology which enables the image sensor to be
placed at the distal tip of the investigating device. The three
most common solid state image sensors include charged coupled
devices (CCD), charge injection devices (CID) and photo diode
arrays (PDA). In the mid-1980s, complementary metal oxide
semiconductors (CMOS) were developed for industrial use. CMOS
imaging devices offer improved functionality and simplified system
interfacing. Furthermore, many CMOS imagers can be manufactured at
a fraction of the cost of other solid state imaging
technologies.
[0005] One particular advance in CMOS technology has been in the
active pixel-type CMOS imagers which consist of randomly accessible
pixels with an amplifier at each pixel site. One advantage of
active pixel-type imagers is that the amplifier placement results
in lower noise levels than CCDs or other solid state imagers.
Another major advantage is that these CMOS imagers can be mass
produced on standard semiconductor production lines. One
particularly notable advance in the area of CMOS imagers including
active pixel-type arrays is the CMOS imager described in U.S. Pat.
No. 5,471,515 to Fossum, et al. This CMOS imager can incorporate a
number of other different electronic controls that are usually
found on multiple circuit boards of much larger size. For example,
timing circuits, and special functions such as zoom and anti-jitter
controls can be placed on the same circuit board containing the
CMOS pixel array without significantly increasing the overall size
of the host circuit board. Furthermore, this particular CMOS imager
requires 100 times less power than a CCD-type imager. In short, the
CMOS imager disclosed in Fossum, et al. has enabled the development
of a "camera on a chip."
[0006] Passive pixel-type CMOS imagers have also been improved so
that they too can be used in an imaging device which qualifies as a
"camera on a chip." In short, the major difference between passive
and active CMOS pixel arrays is that a passive pixel-type imager
does not perform signal amplification at each pixel site. One
example of a manufacturer which has developed a passive pixel array
with performance nearly equal to known active pixel devices and
being compatible with the read out circuitry disclosed in the U.S.
Pat. No. 5,471,515 is VLSI Vision, Ltd., 1190 Saratoga Avenue,
Suite 180, San Jose, Calif. 95129. A further description of this
passive pixel device may be found in applicant's U.S. Pat. No.
5,986,693 entitled "Reduced Area Imaging Devices Incorporated
Within Surgical Instruments," which is hereby incorporated by
reference.
[0007] In addition to the active pixel-type CMOS imager which is
disclosed in U.S. Pat. No. 5,471,515, there have been developments
in the industry for other solid state imagers which have resulted
in the ability to have a "camera on a chip." For example, Suni
Microsystems, Inc. of Mountain View, Calif., has developed a
CCD/CMOS hybrid which combines the high quality image processing of
CCDs with standard CMOS circuitry construction. In short, Suni
Microsystems, Inc. has modified the standard CMOS and CCD
manufacturing processes to create a hybrid process providing CCD
components with their own substrate which is separate from the P
well and N well substrates used by the CMOS components.
Accordingly, the CCD and CMOS components of the hybrid may reside
on different regions of the same chip or wafer. Additionally, this
hybrid is able to run on a low power source (5 volts) which is
normally not possible on standard CCD imagers which require 10 to
30 volt power supplies. A brief explanation of this CCD/CMOS hybrid
can be found in the article entitled "Startup Suni Bets on
Integrated Process" found in Electronic News, Jan. 20, 1997 issue.
This reference is hereby incorporated by reference for purposes of
explaining this particular type of imaging processor.
[0008] Another example of a recent development in solid state
imaging is the development of a CMOS imaging sensor which is able
to achieve analog to digital conversion on each of the pixels
within the pixel array. This type of improved CMOS imager includes
transistors at every pixel to provide digital instead of analog
output that enable the delivery of decoders and sense amplifiers
much like standard memory chips. With this new technology, it may,
therefore, be possible to manufacture a true digital "camera on a
chip." This CMOS imager has been developed by a Stanford University
joint project and is headed by Professor Abbas el-Gamal.
[0009] A second approach to creating a CMOS-based digital imaging
device includes the use of an over-sample converter at each pixel
with a one bit comparator placed at the edge of the pixel array
instead of performing all of the analog to digital functions on the
pixel. This new design technology has been called MOSAD
(multiplexed over sample analog to digital) conversion. The result
of this new process is low power usage, along with the capability
to achieve enhanced dynamic range, possibly up to 20 bits. This
process has been developed by Amain Electronics of Simi Valley,
Calif. A brief description of both of the processes developed by
Stanford University and Amain Electronics can be found in an
article entitled "A/D Conversion Revolution for CMOS Sensor?,"
September 1998 issue of Advanced Imaging. This reference is also
hereby incorporated by reference for purposes of explaining these
particular types of imaging processors.
[0010] The above-mentioned developments in solid state imaging
technology have shown that "camera on a chip" devices will continue
to be enhanced not only in terms of the quality of imaging which
may be achieved, but also in the specific construction of the
devices which may be manufactured by new breakthrough
processes.
[0011] Although the "camera on a chip" concept is one which has
great merit for application in many industrial areas, a need still
exists for a reduced area imaging device which can be used in even
the smallest type of endoscopic instruments in order to view areas
in the body that are particularly difficult to access, and to
further minimize patient trauma by an even smaller diameter
invasive instrument.
[0012] It is one general object of this invention to provide a
wireless endoscope incorporating reduced area imaging devices which
take advantage of "camera on a chip" technology, but rearrange the
circuitry in a stacked relationship so that there is a minimum
profile presented when used within a surgical instrument or other
investigative device. It is another object of this invention to
provide a wireless endoscope utilizing low cost imaging devices
which may be "disposable." It is yet another object of this
invention to provide reduced area imaging devices capable of
wireless communications which may be used in conjunction with
standard endoscopes by placing the imaging device through channels
which normally receive other surgical devices, or receive liquids
or gases for flushing a surgical area It is yet another object of
this invention to provide a surgical device with imaging capability
which may be battery powered and may wirelessly communicate for
viewing video images.
[0013] In addition to the intended use of the wireless endoscope
with respect to surgical procedures conducted by medical doctors,
it is also contemplated that the invention described herein has
great utility with respect to oral surgery and general dental
procedures wherein a very small imaging device can be used to
provide an image of particularly difficult to access locations.
Additionally, while the foregoing invention has application with
respect to the medical and dental fields, it will also be
appreciated by those skilled in the art that the small size of the
imaging device set forth herein coupled with the wireless
communication feature can be applied to other functional
disciplines wherein the imaging device can be used to view
difficult to access locations for industrial equipment and the
like. Therefore, the imaging device of this invention could be used
to replace many industrial boroscopes.
[0014] The "camera on a chip" technology can be furthered improved
with respect to reducing its profile area and incorporating such a
reduced area imaging device into very small investigative
instruments which can be used in the medical dental or other
industrial fields.
DISCLOSURE OF THE INVENTION
[0015] In accordance with the present invention, reduced area
imaging devices are provided. The term "imaging device" as used
herein describes the imaging elements and processing circuitry
which is used to produce a video signal which may be accepted by a
standard video device such as a television or video monitor
accompanying a personal computer. The term "image sensor" as used
herein describes the components of a solid state imaging device
which captures images and stores them within the structure of each
of the pixels in the array of pixels found in the imaging device.
As further discussed below, the timing and control circuits can be
placed either on the same planar structure as the pixel array, in
which case the image sensor can also be defined as an integrated
circuit, or the timing and control circuitry can be placed remote
from the pixel array. The terms "signal" or "image signal" as used
herein, and unless otherwise more specifically defined, refer to an
image which at some point during its processing by the imaging
device, is found in the form of electrons which have been placed in
a specific format or domain. The term "processing circuitry" as
used herein refers to the electronic components within the imaging
device which receive the image signal from the image sensor and
ultimately place the image signal in a usable format. The terms
"timing and control circuits" or "circuitry" as used herein refer
to the electronic components which control the release of the image
signal from the pixel array.
[0016] In a first embodiment of the endoscope, the imaging device
utilizes wired connections for interconnecting the various elements
of the imaging device, and utilizes wired connections for
transferring video images to a video display.
[0017] In a second embodiment of the endoscope, a wireless
communications means may be used to allow various elements of the
imaging device to communicate with one another. Transfer of video
images to a video display can also be achieved by the wireless
communications means. Thus in the second embodiment, the endoscope
does not have to be physically connected to other operating room
equipment which greatly enhances the ease of using the wireless
endoscope. Particularly in endoscopic procedures which are
conducted in hard to reach locations within the body, a wireless
endoscope is advantageous because there are no trailing cables or
sterile drapes which otherwise complicate maneuvering of the
endoscope. In general, enhanced maneuverability of the endoscope is
provided by the wireless communications.
[0018] One particularly advantageous wireless technology usable
with the endoscope of this invention is known as "Bluetooth".
Another recent wireless technology which is usable with the
invention is a wireless protocol known as "IEEE 802.15.13". This
wireless standard is developing under the joint efforts of Kodak,
Motorola, Cisco and the International Electronic and Electrical
Engineers Standards Association (IEEE) Wireless Personal Area
Network Working Group (WPAN). Bluetooth technology provides a
universal radio interface in the 2.4 GHz frequency band that
enables portable electronic devices to connect and communicate
wirelessly via short-range ad hoc networks. Bluetooth radios
operate in an unlicensed Instrumentation, Scientific, Medical (ISM)
band at 2.4 Ghz. Bluetooth is a combination of circuit and packet
switching. Slots can be reserved for synchronous packets. Each
packet is transmitted in a different hop frequency. A packet
nominally covers a single slot, but can be extended to cover up to
five slots. Bluetooth can support an asynchronous data channel, up
to three simultaneous synchronous voice channels, or a channel that
simultaneously supports asynchronous data and synchronous voice.
Spectrum spreading is accomplished by frequency hopping 79 hops
displaced by 1 MHZ starting at 2.402 Ghz and stopping at 2.480 GHz.
The maximum frequency hopping rate is 1600 hops per second. The
nominal link range is 10 centimeters to 10 meters, but can be
extended to more than 100 meters by increasing the transmit power.
A shaped binary FM modulation is applied to minimize transceiver
complexity. The gross data rate is 1 Mb/second. A time division
multiplex scheme is used for full-duplex transmission. Additional
information describing the Bluetooth global specification is found
on the world wide web at www.bluetooth.com. Additional information
regarding the technical specification for the IEEE 802.15.13
standard may be found www.ieee802.org/15 under the link for the
Task Force Three (TG3). The content of both of these websites is
hereby incorporated by reference for purposes of disclosing these
types of communication standards.
[0019] In a first arrangement of the imaging device, the image
sensor, with or without the timing and control circuitry, may be
placed at the distal tip of the endoscopic instrument while the
remaining processing circuitry may be found in a small remote
control box which may wirelessly communicate with the image
sensor.
[0020] In a second arrangement of the imaging device, the image
sensor and the processing circuitry may all be placed in a stacked
arrangement of circuit boards and positioned at the distal tip of
the endoscopic instrument In this second arrangement, the pixel
array of the image sensor may be placed by itself on its own
circuit board while the timing and control circuitry and processing
circuitry are placed on one or more other circuit boards.
Alternatively, the circuitry for timing and control may be placed
with the pixel array on one circuit board, while the remaining
processing circuitry can be placed on one or more of the other
circuit boards.
[0021] In another alternative arrangement, the imaging device may
be adapted for use with a standard rod lens endoscope wherein the
imaging device is placed within a standard camera housing which is
configured to connect to a standard "C" or "V" mount connector.
[0022] In yet another arrangement, the timing and control circuitry
and/or the processing circuitry may be placed in the handle of the
endoscope. It is even completed that some circuitry could be placed
in the handle of the endoscope while remaining circuitry is placed
within the remote control box. Because of the small size of the
elements making up the imaging device coupled with the ability to
provide wireless communications between the elements, great
diversification is provided for the combinations of locations at
which the different elements may be employed.
[0023] A simplified endoscope may be used which includes a very
small diameter tubular portion which is inserted within the patient
The tubular portion may be made of a flexible material having a
central lumen or opening therein for receiving the elements of the
imaging device. The tubular portion may be modified to include an
additional concentric tube placed within the central lumen and
which enables a plurality of light fibers to be placed
circumferentially around the periphery of the distal end of the
tubular portion. Additionally, control wires may extend along the
tubular portion in order to make the endoscope steerable. The
material used to make the endoscope can be compatible with any
desired sterilization protocol, or the entire endoscope can be made
sterile and disposable after use.
[0024] In the second embodiment of the endoscope wherein processing
circuitry is housed within the endoscope, and for the arrangement
of the imaging device which calls for the array of pixels and the
timing and control circuitry to be placed on the same circuit
board, only one conductor is required in order to electrically
transfer the image signal to the processing circuitry. In the other
configuration of the imaging device wherein the timing and control
circuits are incorporated onto other circuit boards, a plurality of
connections are required in order to connect the timing and control
circuitry to the pixel array and the one conductor is also required
to transfer the image signal.
[0025] In each of the different arrangements of the imaging device
where circuitry is housed in the handle of the endoscope, the
handle can have one or more channels or bores for making space
available for such circuitry.
[0026] Thus, the wireless communications made integral with the
endoscope of the second embodiment provides an improved endoscope
wherein the improvement comprises variations of wireless
communications for transmission of image signals that are viewed on
a desired video display.
BRIEF DESCRIPTION OF THE DRAWINGS
[0027] FIG. 1a illustrates a first arrangement of the imaging
device including a fragmentary cross-sectional view of a generic
endoscopic instrument in the first embodiment, and a fragmentary
perspective view of a control box, the endoscope and control box
each incorporating elements of a reduced area imaging device;
[0028] FIG. 1b is an enlarged fragmentary partially exploded
perspective view of the distal end of the endoscopic instrument
specifically illustrating the arrangement of the image sensor with
respect to the other elements of the tubular portion of the
endoscope;
[0029] FIG. 2a is a fragmentary cross-sectional view of the
endoscope in the first embodiment, and a second arrangement of the
imaging device wherein the imaging device is incorporated in its
entirety at the distal tip of the endoscope;
[0030] FIG. 2b is an enlarged fragmentary partially exploded
perspective view of the distal end of the endoscope of FIG. 2a
illustrating the imaging device;
[0031] FIG. 3a is an elevational fragmentary cross-sectional view
of the image sensor incorporated with a standard camera housing for
connection to a rod lens endoscope;
[0032] FIG. 3b is a fragmentary cross-sectional view of the imaging
device incorporated within the camera housing of FIG. 3a;
[0033] FIG. 3c is a fragmentary cross-sectional view similar to
that of FIG. 3b illustrating a battery as an alternate source of
power;
[0034] FIG. 4 is a schematic diagram of the functional electronic
components which make up the imaging device;
[0035] FIG. 4a is an enlarged schematic diagram of a circuit board
which may include the array of pixels and the timing and control
circuitry;
[0036] FIG. 4b is an enlarged schematic diagram of a video
processing board having placed thereon the processing circuitry
which processes the pre-video signal generated by the array of
pixels and which converts the pre-video signal to a post-video
signal which may be accepted by a standard video device;
[0037] FIGS. 5a-5e are schematic diagrams that illustrate an
example of specific circuitry which may be used to make the imaging
device.
[0038] FIG. 6 is a fragmentary cross-sectional view of an endoscope
in the second embodiment wherein image signals in a desired video
ready format are wirelessly transmitted to a remote video display
monitor for viewing by a user;
[0039] FIG. 6a is another fragmentary cross-sectional view of the
endoscope of FIG. 6 showing an alternate source of light in the
form of a fiber optic cable connected to an external light
source.
[0040] FIG. 6b is another fragmentary cross-sectional view of the
endoscope of FIG. 6 showing processing circuitry incorporated
within the handle of the endoscope as opposed to the circuitry
placed within the tubular portion of the endoscope;
[0041] FIG. 7 illustrates a transceiver radio module which receives
image signals transmitted by the wireless endoscope of FIG. 6/FIG.
6a, and conditions the received image signals for direct reception
by a display monitor;
[0042] FIG. 8 illustrates another endoscope of the second
embodiment wherein some image signal processing is conducted remote
from the endoscope;
[0043] FIG. 8a illustrates a removable battery housing which may be
recharged by removing the housing and plugging it into the recharge
receptacle on the control box of FIG. 9; and
[0044] FIG. 9 illustrates the arrangement of the imaging device
which incorporates the control box wherein image signals from the
endoscope in FIG. 8 are in a first or pre-format and are
transmitted wirelessly to the control box, circuitry in the control
box processes the image signals in a second or final format, and
the control box then wirelessly transmits the image signals to a
secondary receiver which receives the image signals and conditions
the image signals for direct reception by the display monitor.
BEST MODE FOR CARRYING OUT THE INVENTION
[0045] In accordance with one arrangement of the imaging device as
shown in FIG. 1a, an endoscope 10 in the first embodiment is
provided which incorporates a reduced area imaging device 11, shown
in FIG. 1b. As further discussed below, the elements of the imaging
device may all be found at one location or the elements may be
separated from one another and interconnected by the appropriate
cable(s). The array of pixels making up the image sensor captures
images and stores them in the form of electrical energy by
conversion of light photons to electrons. This conversion takes
place by the photo diodes in each pixel which communicate with one
or more capacitors which store the electrons. The structure of the
endoscope 10 in the first embodiment includes a flexible or rigid
tubular portion 14 which is inserted into the body of the patient
and is placed at the appropriate location for viewing a desired
surgical area The tubular portion 14 attaches at its proximal end
to a handle portion 12 which may be grasped by a surgeon who is
conducting the endoscopic procedure. The handle 12 may include a
central lumen or channel 13 which receives one or more cables or
other structures which extend to the distal end 16 of tubular
portion 14. Handle portion 12 may further include a supplementary
channel 15 which intersects with central channel 13 and which may
provide another point of entry for other cables, fluids or
operative instruments to be placed through the endoscope.
[0046] FIG. 1b illustrates the distal end of the endoscope 16. The
distal end 16 may be characterized by an outer tube 18 which
traverses the length of the tubular portion 14 and connects to the
handle portion 12. Placed concentrically within the outer tube 18
may be one or more inner tubes 20. In FIG. 1b, the gap between
inner tube 20 and outer tube 18 forms a space in which one or more
light fibers 22 or control wires 24 may be placed. As well
understood by those skilled in the art, a plurality of
circumferentially spaced light fibers as illustrated in FIG. 1b can
be used to illuminate the surgical site. Additionally, the control
wires 24 may communicate with a control mechanism (not shown)
integrated on the handle portion 12 for manipulating the distal end
16 of the endoscope in a desired direction. The flexible tubular
portion 14 coupled with a steerable feature enables the endoscope
to be placed within winding bodily passages or other locations
difficult to reach within the body.
[0047] An image sensor 40 may be placed within the central channel
defined by inner tube 20. In the configuration shown in FIG. 1b, a
cable 26 is used to house the conductors which communicate with the
image sensor 40. An intermediate support tube 28 may be placed
concentrically outside of cable 26 and concentrically within inner
tube 20 to provide the necessary support for the cable 26 as it
traverses through the inner channel defined by inner tube 20. In
lieu of support tube 28, other well-known means may be provided to
stabilize the cable 26 such as clips or other fastening means which
may attach to the inner concentric surface of inner tube 20.
[0048] A control box 30 may be placed remote from the endoscope 10.
The control box 30 contains some of the processing circuitry which
is used to process the image signal produced by image sensor 40.
Therefore, the imaging device 11 as previously defined would
include the processing circuitry within control box 30 and the
image sensor 40 located at the distal tip of the endoscope. Control
box 30 communicates with image sensor 40 by means of cable 32 which
may simply be an insulated and shielded cable which houses therein
cable 26. Cable 32 is stabilized with respect to the handle portion
12 by means of a fitting 34 which ensures that cable 32 cannot be
inadvertently pushed or pulled within channel 13. Additionally, an
additional fitting 35 may be provided to stabilize the entry of a
light cable 36 which houses the plurality of light fibers 22. Light
cable 36 runs along cable 32 to the distal end of the endoscope, or
light cable 36 can join cable 32 within the channel 13 as shown in
FIG. 1a. Thus cable 32 would house both the light fibers and the
conductors which interconnect the control box 30 to the image
sensor 40.
[0049] Image sensor 40 is illustrated as being a planar and square
shaped member. However, the image sensor may be modified to be in a
planar and circular shape to better fit within the channel defined
by inner tube 20. Accordingly, FIG. 1b further shows an alternate
shaped image sensor 40' which is round. A lens group or system 42
may be incorporated at the distal end of the endoscope in order to
manipulate the image prior to it being impinged upon the array of
pixels on the image sensor 40. This lens system 42 may be sealed at
the distal end 16 of the endoscope so that the tubular portion 14
is impervious to fluids entering through the distal end 16. In the
configuration of the imaging device 11 in FIGS. 1a and 1b, there
are only three conductors which are necessary for providing power
to the image sensor 40, and for transmitting an image from the
image sensor 40 back to the processing circuitry found within
control box 30. Namely, there is a power conductor 44, a grounding
conductor 46, and an image signal conductor 48 each of which are
hard wired to the image sensor. Thus, cable 26 may simply be a
three-conductor 50 ohm cable.
[0050] Image sensor 40 can be as small as 1 mm in its largest
dimension. However, a more preferable size for most endoscopic
procedures would dictate that the image sensor 40 be between 4 mm
to 8 mm in its largest dimension. The image signal electrically
transmitted from the image sensor through conductor 48 is also
herein referred to as a pre-video signal. Once the pre-video signal
has been electrically transmitted from image sensor 40 by means of
conductor 48, it is received by video processing board 50. Video
processing board 50 then carries out all the necessary conditioning
of the pre-video signal and places it in a form so that it may be
viewed directly on a standard video device, television or standard
computer video monitor. The signal produced by the video processing
board 50 can be further defined as a post-video signal which can be
accepted by a standard video device. As shown in FIG. 1a, a
conductor 49 is provided which electrically transmits the
post-video signal to an output connector 58 on the exterior surface
of control box 30. The cable (not shown) extending from the desired
video device (not shown) may receive the post-video signal by means
of connector 58. Power supply board 52 may convert incoming power
received through power source 54 into the desired voltage. In the
preferred imager incorporated in this invention, the power to the
imaging device is simply a direct current which can be a 1.5 volt
to a 12 volt source. Incoming power from, for example, a wall
receptacle, communicates with power supply board 52 by connector
56. Power supply board 52 takes the incoming power source and
regulates it to the desired level. Additionally, ground 46 is also
shown as extending back to the source of power through connector
56.
[0051] FIG. 2a illustrates a second arrangement of the imaging
device wherein the imaging device is self-contained entirely within
the distal end 16 of the endoscope, and a power source which drives
the circuitry within the imaging device may come from a battery 66
housed within handle portion 12.
[0052] As shown in FIG. 2b, the video processing board 50 may be
placed directly behind image sensor 40. A plurality of pin
connectors 62 serve to electrically couple image sensor 40 with
video processing board 50 depending upon the specific configuration
of image sensor 40, pin connectors 62 may be provided either for
structural support only, or to provide a means by which image
signals are electrically transmitted between image sensor 40 and
board 50. When necessary, one or more supplementary boards 60 may
be provided which further contain processing circuitry to process
the image signal and present it in a form which may be directly
received by a desired video device. The area which is occupied by
image sensor 40 may be defined as the profile area of the imaging
device and which determines its critical dimensions. Any imaging
elements that are found on boards 50 or 60 must be able to be
placed on one or more circuit boards which are longitudinally
aligned with image sensor 40 along longitudinal axis XX. If the
profile area is not critical in terms of limiting the largest sized
imaging element within the imaging device, then the additional
circuit boards 50 and 60 which are normally placed in line with
image sensor 40 can be aligned in an offset manner or may be larger
than the profile area of image sensor 40. In the configuration of
FIG. 2b, it is desirable that elements 40, 50 and 60 be
approximately the same size so that they may fit uniformly within
the central channel of the endoscope. Additionally, image sensor 40
may be bonded to lens system 42 in order to provide further
structural support to the imaging device 11 when mounted within the
distal end 16.
[0053] Referring back to the handle portion 12 in FIG. 2a, an
additional channel 64 may be provided in order that a power supply
cable 68 may communicate with battery 66. Conveniently, battery 66
may itself be mounted within a well 65 formed in handle portion 12.
Cable 68 carries the conductor 44 and ground 46. Cable 68 may
intersect with cable 33 within channel 13, cables 68 and 33
extending then to the distal end 16. Cable 33 can be a single
conductor cable which transmits the post-video signal to a desired
video device. In other words, cable 33 may simply be an insulated
and shielded housing for conductor 49 which carries the post-video
signal. Because a preferred image sensor of the imaging device 11
may only require a 5 volt power supply, a battery is an ideal power
source in lieu of a conductor which would trail the endoscope.
Accordingly, the endoscope is made more mobile and easier to handle
by eliminating at least one of the trailing cables.
[0054] FIG. 3a illustrates yet another arrangement or configuration
of the imaging device wherein the imaging device can be used in
conjunction with a standard rod lens endoscope 70. As shown, rod
lens endoscope 70 includes a lens train 72 which includes a
plurality of highly precise lenses (not shown) which are able to
transmit an image from the distal end of the endoscope, to a camera
in line with the endoscope. The rod lens endoscope is equipped with
a light guide coupling post 74. Light guide post 74 connects to a
source of light in the form of a cable 77 having a plurality of
fiber optic strands (not shown) which communicate with a source of
light (not shown). The most common arrangement of the rod lens
endoscope also includes a "C" or "V" mount connector 78 which
attaches to the eyepiece 76. The "C" or "V" mount attaches at its
other end to a camera group 80. The camera group 80 houses one or
more of the elements of the imaging device. In this configuration,
the small size of the imaging device is not a critical concern
since the imaging device is not being placed at the distal end of
the endoscope. However, the incorporation of the imaging device in
a housing which would normally hold a traditional camera still
provides an advantageous arrangement As shown, the camera group 80
may include a housing 82 which connects to a power/video cable 86.
Fitting 87 is provided to couple cable 86 to the interior elements
of the camera group 80 found within housing 82. FIG. 3a illustrates
an arrangement of the imaging device 11 wherein the image sensor 40
is placed by itself within the housing 82 and the processing
circuitry of the imaging device can be positioned in a remote
control box as shown in FIG. 1a. Accordingly, only three conductors
44, 46 and 48 are necessary for providing power to the image sensor
40 and for transmitting the pre-video signal to the control box.
Alternatively, as shown in FIG. 3b, the entire imaging device 11
may be incorporated within camera group 80, each of the elements of
the imaging device being placed in the stacked arrangement similar
to FIG. 2b. As discussed above, size is not as much of a concern in
the embodiment of FIGS. 3a and 3b since the camera group housing 82
is much larger than the distal tip of the endoscope of FIGS. 1a and
2a.
[0055] FIG. 3c also illustrates the use of a battery 66 which
provides source of power to the imaging device in either FIG. 3a or
3b. In this arrangement, housing 82 is altered to include a battery
housing 69 which houses the battery 66 therein. Battery housing 69
may include a very small diameter channel which may allow conductor
48 or 49 to communicate directly with the processing circuitry or
video device, respectively. It will also be understood that the
embodiment in FIG. 1a may incorporate the use of a battery 66 as
the source of power. Thus, handle 12 in FIG. 1a may be altered in
the same way as housing 82 to allow a battery to be attached to the
handle portion 12.
[0056] In all of the arrangements of the imaging device discussed
above with respect to the first embodiment of the endoscope, each
of the elements or components of the imaging device electrically
communicate with one another through a wired connection.
[0057] FIG. 4 is a schematic diagram illustrating one way in which
the imaging device 11 may be constructed. As illustrated, the image
sensor 40 may include the timing and control circuits on the same
planar structure. Power is supplied to image sensor 40 by power
supply board 52. The connection between image sensor 40 and board
52 may simply be a cable having two conductors therein, one for
ground and another for transmitting the desired voltage. These are
illustrated as conductors 44 and 46. The output from image sensor
40 in the form of the pre-video signal is input to video processor
board 50 by means of the conductor 48. In the configuration of FIG.
4, conductor 48 may simply be a 50 ohm conductor. Power and ground
also are supplied to video processing board 50 by conductors 44 and
46 from power supply board 52. The output signal from the video
processor board 50 is in the form of the post-video signal and
which may be carried by conductor 49 which can also be a 50 ohm
conductor.
[0058] In the first arrangement of the imaging device illustrated
in FIG. 1a, cable 32 can be used to house conductors 44, 46 and 48.
In the arrangement shown in FIG. 2a, cable 33 can be used to house
conductor 49 by itself when a battery power source is used, or
alternatively, cable 33 may house conductors 44, 46 and 49 if the
arrangement of FIG. 2a utilizes a power source from board 52.
[0059] Optionally, a supplementary processing board 60 may be
provided to further enhance the pre-video signal. As shown in FIG.
4, the supplementary board 60 may be placed such that the pre-video
signal from image sensor 40 is first sent to the supplementary
board and then output to the video processor board 50. In this
case, the output from board 50 can be carried along conductor 51.
This output can be defined as an enhanced pre-video signal.
Furthermore, the post-video signal from video processor board 50
may return to the supplementary board 60 for further processing, as
further discussed below. The conductor used to electrically
transmit the post-video signal back to the supplementary board is
shown as conductor 59. The power supply board 52 may also provide
power to the supplementary board in the same manner as to image
sensor 40 and board 50. That is, a simple hard-wired connection is
made onto the supplementary board for the ground and voltage
carrying conductors. As discussed above, image sensor 40 may be
placed remotely from boards 50 and 60. Alternatively, image sensor
40, and boards 50 and 60 each may be placed within the distal end
of the endoscope.
[0060] Although FIG. 4 illustrates the image sensor and the timing
and control circuits being placed on the same planar structure, it
is possible to separate the timing and control circuits from the
pixel array and place the timing and control circuits onto video
processing board 50. The advantage in placing the timing and
control circuits on the same planar structure as the image sensor
is that only three connections are required between image sensor 40
and the rest of the imaging device, namely, conductors 44, 46 and
48. Additionally, placing the timing and control circuits on the
same planar structure with the pixel array results in the pre-video
signal having less noise. Furthermore, the addition of the timing
and control circuits to the same planar structure carrying the
image sensor only adds a negligible amount of size to one dimension
of the planar structure. If the pixel array is to be the only
element on the planar structure, then additional connections must
be made between the planar structure and the video processing board
50 in order to transmit the clock signals and other control signals
to the pixel array. For example, a ribbon-type cable (not shown) or
a plurality of 50 ohm coaxial cables (not shown) must be used in
order to control the downloading of information from the pixel
array. Each of these additional connections would be hard wired
between the boards.
[0061] FIG. 4a is a more detailed schematic diagram of image sensor
40 which contains an array of pixels 90 and the timing and control
circuits 92. One example of a pixel array 90 which can be used
within the invention is similar to that which is disclosed in U.S.
Pat. No. 5,471,515 to Fossum, et al., said patent being
incorporated by reference herein. More specifically, FIG. 3 of
Fossum, et al. illustrates the circuitry which makes up each pixel
in the array of pixels 90. The array of pixels 90 as described in
Fossum, et al. is an active pixel group with intra-pixel charged
transfer. The image sensor made by the array of pixels is formed as
a monolithic complementary metal oxide semiconductor integrated
circuit which may be manufactured in an industry standard
complementary metal oxide semiconductor process. The integrated
circuit includes a focal plane array of pixel cells, each one of
the cells including a photo gate overlying the substrate for
accumulating the photo generated charges. In broader terms, as well
understood by those skilled in the art, an image impinges upon the
array of pixels, the image being in the form of photons which
strike the photo diodes in the array of pixels. The photo diodes or
photo detectors convert the photons into electrical energy or
electrons which are stored in capacitors found in each pixel
circuit. Each pixel circuit has its own amplifier which is
controlled by the timing and control circuitry discussed below. The
information or electrons stored in the capacitors is unloaded in
the desired sequence and at a desired frequency, and then sent to
the video processing board 50 for further processing.
[0062] Although the active pixel array disclosed in U.S. Pat. No.
5,471,515 is mentioned herein, it will be understood that the
hybrid CCD/CMOS described above, or any other solid state imaging
device may be used wherein timing and control circuits can be
placed either on the same planar structure with the pixel array, or
may be separated and placed remotely. Furthermore, it will be
clearly understood that the invention claimed herein is not
specifically limited to an image sensor as disclosed in the U.S.
Pat. No. 5,471,515, but encompasses any image sensor which may be
configured for use in conjunction with the other processing
circuitry which makes up the imaging device of this invention.
[0063] The timing and control circuits 92 are used to control the
release of the image information or image signal stored in the
pixel array. In the image sensor of Fossum, et al., the pixels are
arranged in a plurality of rows and columns. The image information
from each of the pixels is first consolidated in a row by row
fashion, and is then downloaded from one or more columns which
contain the consolidated information from the rows. As shown in
FIG. 4a, the control of information consolidated from the rows is
achieved by latches 94, counter 96, and decoder 98. The operation
of the latches, counter and decoder is similar to the operation of
similar control circuitry found in other imaging devices. That is,
a latch is a means of controlling the flow of electrons from each
individual addressed pixel in the array of pixels. When a latch 94
is enabled, it will allow the transfer of electrons to the decoder
98. The counter 96 is programmed to count a discrete amount of
information based upon a clock input from the timing and control
circuits 92. When the counter 96 has reached its set point or
overflows, the image information is allowed to pass through the
latches 94 and be sent to the decoder 98 which places the
consolidated information in a serial format Once the decoder 98 has
decoded the information and placed it in the serial format then the
row driver 100 accounts for the serial information from each row
and enables each row to be downloaded by the column or columns. In
short the latches 94 will initially allow the information stored in
each pixel to be accessed. The counter 96 then controls the amount
of information flow based upon a desired time sequence. Once the
counter has reached its set point the decoder 98 then knows to take
the information and place it in the serial format The whole process
is repeated, based upon the timing sequence that is programmed.
When the row driver 100 has accounted for each of the rows, the row
driver reads out each of the rows at the desired video rate.
[0064] The information released from the column or columns is also
controlled by a series of latches 102, a counter 104 and a decoder
106. As with the information from the rows, the column information
is also placed in a serial format which may then be sent to the
video processing board 50. This serial format of column information
is the pre-video signal carried by conductor 48. The column signal
conditioner 108 places the column serial information in a
manageable format in the form of desired voltage levels. In other
words, the column signal conditioner 108 only accepts desired
voltages from the downloaded column(s).
[0065] The clock input to the timing and control circuits 92 may
simply be a quartz crystal timer. This clock input is divided into
many other frequencies for use by the various counters. The run
input to the timing and control circuit 92 may simply be an on/off
control. The default input can allow one to input the pre-video
signal to a video processor board which may run at a frequency of
other than 30 hertz. The data input controls functions such as
zoom. At least for a CMOS type active pixel array which can be
accessed in a random manner, features such as zoom are easily
manipulated by addressing only those pixels which locate a desired
area of interest by the surgeon.
[0066] A further discussion of the timing and control circuitry
which may be used in conjunction with an active pixel array is
disclosed in U.S. Pat. No. 5,471,515 and is also described in an
article entitled "Active Pixel Image Sensor Integrated With Readout
Circuits" appearing in NASA Tech Briefs, October 1996, pp. 38 and
39. This particular article is also incorporated by reference.
[0067] Once image sensor 40 has created the pre-video signal it is
sent to the video processing board 50 for further processing. At
board 50, as shown in FIG. 4b, the pre-video signal is passed
through a series of filters. One common filter arrangement may
include two low pass filters 114 and 116, and a band pass filter
112. The band pass filter only passes low frequency components of
the signal. Once these low frequency components pass, they are then
sent to detector 120 and white balance circuit 124, the white
balance circuit distinguishing between the colors of red and blue.
The white balance circuit helps the imaging device set its normal,
which is white. The portion of the signal passing through low pass
filter 114 then travels through gain control 118 which reduces the
magnitude or amplitude of this portion to a manageable level. The
output from gain control 118 is then fed back to the white balance
circuit 124. The portion of the signal traveling through filter 116
is placed through the processor 122. In the processor 122, the
portion of the signal carrying the luminance or non-chroma is
separated and sent to the Y chroma mixer 132. Any chroma portion of
the signal is held in processor 122.
[0068] Referring to the output of the white balance circuit 124,
this chroma portion of the signal is sent to a delay line 126 where
the signal is then further reduced by switch 128. The output of
switch 128 is sent through a balanced modulator 130 and also to the
Y chroma mixer 132 where the processed chroma portion of the signal
is mixed with the processed non-chroma portion. Finally, the output
from the Y chroma mixer 132 is sent to the NTSC/PAL encoder 134,
commonly known in the art as a "composite" encoder. The composite
frequencies are added to the signal leaving the Y chroma mixer 132
in encoder 134 to produce the post-video signal which may be
accepted by a television or other video display device.
[0069] Referring back to FIG. 4, it further illustrates
supplementary board 60 which may be used to digitally enhance or
otherwise further condition the pre-video signal produced from
image sensor 40. For example, digital enhancement can brighten or
otherwise clarify the edges of an image viewed on a video screen.
Additionally, the background images may be removed thus leaving
only the foreground images or vice versa The connection between
image sensor 40 and board 60 may simply be the conductor 48 which
may also transfer the pre-video signal to board 50. Once the
pre-video signal has been digitally enhanced on supplementary board
60, it is then sent to the video processor board 50 by means of
another conductor 51. The pre-video signal is an analog signal. The
digitally enhanced pre-video signal may either be a digital signal
or it may be converted back to the analog domain prior to being
sent to board 50.
[0070] In addition to digital enhancement, supplementary board 60
may further include other circuitry which may further condition the
post-video signal so that it may be viewed in a desired format
other than NTSC/PAL. As shown in FIGS. 4, intermediate conductor 59
may transmit the signal output from Y chroma mixer 132 back to the
supplementary board 60 where the signal is further encoded for
viewing in a particular format. One common encoder which can be
used includes an RGB encoder 154. The RGB encoder separates the
signal into three separate colors (red, green and blue) so that the
surgeon may selectively choose to view only those images containing
one or more of the colors. Particularly in tissue analysis where
dyes are used to color the tissue, the RGB encoder may help the
surgeon to identify targeted tissue.
[0071] The next encoder illustrated in FIG. 4 is a SVHS encoder 156
(super video home system). This encoder splits or separates the
luminance portion of the signal and the chroma portion of the
signal prior to entering the video device. Some observers believe
that a cleaner signal is input to the video device by such a
separation which in turn results in a more clear video image viewed
on the video device. The last encoder illustrated in FIG. 4 is a
VGA encoder 158 which enables the signal to be viewed on a standard
VGA monitor which is common to many computer monitors.
[0072] One difference between the arrangement of image sensor 40
and the outputs found in FIG. 3 of the Fossum, et al. patent is
that in lieu of providing two analog outputs [namely, VS out
(signal) and VR out (reset)], the reset function takes place in the
timing and control circuitry 92. Accordingly, the pre-video signal
only requires one conductor 48.
[0073] FIGS. 5a-5e illustrate in more detail one example of
circuitry which may be used in the video processing board 50 in
order to produce a post-video signal which may be directly accepted
by a video device such as a television. The circuitry disclosed in
FIGS. 5a-5e is very similar to circuitry which is found in a
miniature quarter-inch Panasonic camera, Model KS-162. It will be
understood by those skilled in the art that the particular
arrangement of elements found in FIGS. 5a-5e are only exemplary of
the type of video processing circuitry which may be incorporated in
order to take the pre-video signal and condition it to be received
by a desired video device.
[0074] As shown in FIG. 5a, 5 volt power is provided along with a
ground by conductors 44 and 46 to board 50. The pre-video signal
carried by conductor 48 is buffered at buffer 137 and then is
transferred to amplifying group 138. Amplifying group 138 amplifies
the signal to a usable level as well as achieving impedance
matching for the remaining circuitry.
[0075] The next major element is the automatic gain control 140
shown in FIG. 5b. Automatic gain control 140 automatically controls
the signal from amplifying group 138 to an acceptable level and
also adds other characteristics to the signal as discussed below.
More specifically, automatic gain control 140 conditions the signal
based upon inputs from a 12 channel digital to analog converter
141. Converter 141 retrieves stored information from EEPROM
(electrically erasable programmable read only memory) 143. EEPROM
143 is a non-volatile memory element which may store user
information, for example, settings for color, tint, balance and the
like. Thus, automatic gain control 140 changes the texture or
visual characteristics based upon user inputs. The signal leaving
the automatic gain control 140 is an analog signal until being
converted by analog to digital converter 142.
[0076] Digital signal processor 144 of FIG. 5c further processes
the converted signal into a serial type digital signal. One
function of the microprocessor 146 is to control the manner in
which digital signal processor 144 sorts the digital signals
emanating from converter 142. Microprocessor 146 also controls
analog to digital converter 142 in terms of when it is activated,
when it accepts data, when to release data, and the rate at which
data should be released. Microprocessor 146 may also control other
functions of the imaging device such as white balance. The
microprocessor 146 may selectively receive the information stored
in the EEPROM 143 and carry out its various commands to further
control the other elements within the circuitry.
[0077] After the signal is processed by digital signal processor
144, the signal is sent to digital encoder 148 illustrated in FIG.
5d. Some of the more important functions of digital encoder 148 are
to encode the digital signal with synchronization, modulated
chroma, blanking, horizontal drive, and the other components
necessary so that the signal may be placed in a condition for
reception by a video device such as a television monitor. As also
illustrated in FIG. 5d, once the signal has passed through digital
encoder 148, the signal is reconverted into an analog signal
through digital to analog converter 150.
[0078] This reconverted analog signal is then buffered at buffers
151 and then sent to amplifier group 152 of FIG. 5e which amplifies
the signal so that it is readily accepted by a desired video
device. Specifically, as shown in FIG. 5e, one SVHS outlet is
provided at 160, and two composite or NTSC outlets are provided at
162 and 164, respectively.
[0079] Now turning to a discussion of the endoscope of the second
embodiment, attention is first directed to FIG. 6. In this second
embodiment, like reference numerals denote matching elements from
the endoscope of the first embodiment. The endoscope of the second
embodiment also can be characterized as a common or generic
endoscope except for the imaging device and the wireless
communications means incorporated in this second embodiment FIG. 6
more specifically illustrates the arrangement of the imaging device
wherein processing of the image signals is conducted within the
endoscope such that a post-video signal is ready for transmission
to a display monitor. As shown, video processing board 50 is
mounted adjacent the image sensor 40 in the distal tip of the
endoscope. As discussed above, one or more supplementary boards 60
may also be mounted adjacent the video processing board 50 for
further processing of the image signals to produce a post-video
signal of a desired format Alternatively, and as further discussed
below, some or all of the processing circuitry may be mounted
within the handle 12, in a specified portion of the channel 13.
There is ample room within channel 13, or some other bore which
could be formed in the handle to receive processing circuitry. The
construction of the distal tip of the endoscope in the second
embodiment can be the same as in the first embodiment. Thus,
steering wires (not shown) and circumferentially spaced light
fibers (not shown) may be incorporated in the endoscope. Cable 32
carrying the post-video signals electrically connects to a
transceiver radio element 170 which is housed within channel 13
towards the proximal end of the handle 12. Transceiver radio
element 170 conditions the post video signals in accordance with
the desired wireless standard. More specifically, the transceiver
radio element adds a high frequency carrier signal and baseband
protocol to the post video signals, and then wirelessly transmits
the post video signals via antennae 174 to the transceiver radio
module 178. The transceiver radio module 178 authenticates the
received signals, strips the signals of the carrier frequency, and
then routs the signals in the final video format to a display
monitor 196. It should also be understand that the communications
between the transceiver radio element 170 and the transceiver radio
module 178 are not simply one-way communications; rather, the
communications are two way in accordance with the Bluetooth
standard or IEEE standard. For example, not only does the
transceiver radio element 170 transmit image signals, but the
transceiver radio element 170 also receives and processes
authentication signals from the radio transceiver module 178.
Similarly, not only does the transceiver radio module 178 receive
and process image signals, but the module 178 also transmits
authentication signals. A power switch (not shown) may also be
incorporated within the endoscope to selectively energize or
de-energize the image sensor 40 and the transceiver radio element
170.
[0080] Transceiver radio module 178 receives the post-video signals
via antennae 180, decodes the signals, and then electrically
transmits them to the monitor 196 for viewing by the user. The
endoscope in this second embodiment is powered by a battery 176
which is housed adjacent the antennae 174. Electrical leads (not
shown) extend from the battery 176 to power the image sensor and
the transceiver radio element 170. As discussed further below,
antennae 174 and battery 176 may be secured within their own casing
or housing 172 which then connects to the handle 12 of the
endoscope. Transceiver radio module 178 may simply be powered by
the same electrical power source (not shown) which powers the
display monitor 196, such as conventional 110 volt, 3 phase power.
In order to recharge the battery 176 of the endoscope, the
transceiver radio module may be a combination unit which also has a
battery charge circuit 182 for recharging battery 176. Charge
circuit 182 would also be powered by a conventional power source,
preferably the same power source powering the transceiver module
178 and the display monitor 196. Circuit 182 would have a charging
receptacle, shown schematically as receptacle 186, for receiving
the battery 176. FIG. 6 also shows a self-contained white light
source in the form of light source 192 which is housed in channel
15 between interior plug 194 and exterior plug or access cover 195.
Alternatively, as shown in FIG. 6a, an exterior source of light 198
could be used which transmits light through the cable 36. The self
contained light source 192 is preferred because the endoscope is
then free from all trailing cables or other wiring.
[0081] FIG. 6b illustrates the endoscope having another cavity or
opening 210 formed therein for housing some or all of the
processing circuitry. As shown, the video processor board 50 has
been moved to the opening 210 and is supported in the opening by
support 212 which is placed in the opening 210 at a selected depth
to accommodate the particular sized circuitry placed in the
opening. Conductor 214 interconnects the board 50 with image sensor
40, and conductor 214 can run coterminously with cable 32.
Accordingly, the only imaging device element remaining in the
distal end of the endoscope is the image sensor 40. Additionally,
the timing and control circuits 92 could also be placed in the
opening 210 along with the video processing circuitry. The
co-pending application Ser. No. 09/368,246 is also incorporated
herein by reference for purposes of disclosing circuitry placed in
the handle of the endoscope.
[0082] FIGS. 8 and 9 illustrate another arrangement of the imaging
device incorporated within the endoscope of the second embodiment
In preface, FIGS. 8 and 9 illustrate the arrangement in which some
elements of the imaging device are placed within the endoscope, and
remaining elements of the imaging device are placed within the
control box 30. Wireless transmission of image signals takes place
between the endoscope and the control box. Final transmission of
the post-video signal can then be conducted either electrically
through a cable interconnecting the display monitor and the control
box, or final transmission may take place via another wireless
transmission of the post-video signal from the control box to the
display monitor.
[0083] Referring first to FIG. 8, the endoscope is shown which is
identical to the endoscope shown in FIG. 6 with the exception that
there is no video processor board 50 or other associated video
processing circuitry housed within the endoscope. Thus, the
transceiver radio element 170 receives a pre-video signal form the
image sensor 40, and then wirelessly transmits the pre-video signal
to the control box 30. The transceiver radio module 178 receives
the pre-video signal and transfers the same to video processor
board 50. Video processor board 50 alone or in conjunction with
other processing circuitry such as a supplementary processing board
60 (not shown) places the image signal in a post-video format for
direct reception by the display monitor 196. Additionally, it is
also contemplated that the timing and control circuitry 92 could be
placed in the control box 30. In such a case, the transceiver radio
module 178 would not only transit authentication signals, but also
signals generated from the timing and control circuitry 92 for
controlling the image sensor 40.
[0084] In lieu of a camera battery charge circuit incorporated
within a unit which is co-located with the display monitor as shown
in FIG. 7, the charge circuit 182 may be housed within the control
box 30. Accordingly, circuit 182 could be powered by power supply
board 52. Additionally, a camera power switch 184 could be included
within control box 30 to selectively energize or de-energize the
video processor board and its function in converting pre-video
signals to post-video signals. As in the endoscope of FIG. 6, the
endoscope of FIG. 8 could also have its own power switch (not
shown) to energize or de-energize functioning of the imaging
elements and the transceiver radio module 170.
[0085] FIG. 9 also illustrates a secondary communications scheme
whereby the post video signals could be wirelessly transmitted to
the display monitor 196. Optionally, video processor board 50 (or
other processing circuitry) could electrically communicate with a
secondary RF transmitter 200 which would transit the post-video
signals via antennae 202. These post-video signals would then be
received via antennae 206 by a secondary RF receiver 204 mounted
adjacent the display monitor 196. For this secondary transmission,
Bluetooth could be used; however, it would be preferable to use a
different transmission standard between the primary and the
secondary communications to prevent potential interference. One
example of a secondary RF transmitter which could be used is an
rf-video transmitter model no. SDX-22, manufactured by RF-Video.com
of Toronto, Canada. This type of transmitter also operates in the
2.4 GHz frequency, and provides 80 mW of RF power. An example of an
acceptable secondary RF receiver which could be used is an rf-video
receiver model no. VRX-24 also manufactured by RF-Video.com. This
type of receiver has an adjustable frequency of 2.2 to 2.7 Ghz.
[0086] FIG. 8a illustrates that the battery 176 may be removed from
the endoscope for recharge. As shown, housing 172 carries both the
antennae 174 and the battery 176; however, it shall be understood
that the housing 176 could alternatively only carry the battery
176, while the antennae 174 could be housed within channel 13 of
the endoscope. One practical reason for placing antennae 174 within
housing 172 is that the antennae is more easily replaced if it is
located within a removable element The distal end of the housing
172 is received within well or bore 208 in the endoscope. Well 208
could be threaded to match external threads on the distal end of
the housing 172, or other means such as a clip or a friction fit
could be used as understood by those skilled in the art in order to
connect housing 172 to the endoscope. Similarly, the proximal end
of the housing 172 could be threaded or otherwise adapted so that
the proximal end of the housing 172 could be received by receptacle
186 for recharge of the battery 176. As yet another option for
recharge of the battery 176, a recharge cable 188 including
respective fittings/connectors 190 at each end of the cable 188
could be used to interconnect battery 176 with receptacle 186. Thus
if cable 188 were used, housing 172 could remain attached to the
endoscope. One situation which might lend itself for use of cable
188 would be if battery 176 became discharged to the point where it
failed or was in danger of failing to provide enough potential to
the image sensor and transceiver radio element during a surgical
procedure. Cable 188 could then be used to provide instantaneous
power to the endoscope.
[0087] From the foregoing, it is apparent that an entire imaging
device may be incorporated within the distal tip of an endoscope,
or may have some elements of the imaging device being placed in a
small remote box adjacent to the endoscope. Based upon the type of
image sensor used, the profile area of the imaging device may be
made small enough to be placed into an endoscope which has a very
small diameter tube. Additionally, the imaging device may be placed
into the channels of existing endoscopes to provide additional
imaging capability without increasing the size of the endoscope.
The imaging device may be powered by a standard power input
connection in the form of a power cord, or a small battery may be
used. In order to enhance the freedom of using the endoscope
without trailing cables, the endoscope may include wireless
transmission capabilities. A wireless endoscope also has advantages
with respect to overall surgical efficiency in conducting
procedures by minimizing requirements to drape or shield cables in
the sterile field, and by providing an endoscope which has
unlimited movement capabilities without having to orient or
otherwise handle the endoscope to account for twisted cables,
drapes, or other components which are normally associated with
endoscopic devices. A wireless transmission of post-video signals
from the endoscope directly to the video display can be done to
provide video images. Alternatively, the imaging device can be
separated into components which are located in the endoscope and in
a remote control box Pre-video signals are wirelessly transmitted
to the control box, and then post-video signals are provided to the
video display either through a secondary wireless transmission, or
by a conventional hard wired connection.
[0088] This invention has been described in detail with reference
to particular embodiments thereof, but it will be understood that
various other modifications can be effected within the spirit and
scope of this invention.
* * * * *
References