Note: Descriptions are shown in the official language in which they were submitted.
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ENDOSCOPE
BACKGROUND OF THE INVEN~ION
Field of the Invention:
Fiber optic instruments with particular reference
to medical endoscopes.
Discussion of the Prior Art:
In medical endoscopes, as well as in their industrial
counterparts, space within the flexible probe is at a
premium due to the various functions which must be
accommodated, e~g. image transfer, illumination OI the
object, articulation, biopsy channelling etc. Each of
these features is essential to the operation of the
instrument and the space given over to each one involves
a trade-off in the desired performance.
Accordingly, a principle object o this invention
is to reduce the space requirement for one function to
allow more space for the others, e.g. to reduce the
space requirement for illumination of the object in
favor of a larger diameter image carrying bundle to
provide better image quality or improvements in articulation
mechanisms and~or incorporation of larger or added
medical channelling for greater object accessibility.
Other objects and advantages of the invention will
become apparent from the following description.
SU~1~ARY OF THE INVENTION
The foregoing object and its corollaries are
accomplished in the structure of an endoscope by provicing
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an unusually small illuminating iber kundle, e.g. a single
fiber or two, and pro~imally intensi-Eying the light of the
transmitted image. Image magniication with a fiber optic
taper as well as intensification is contemplated.
Since the area ordinarily given over to illuminating
fibers is nearly equal to the image carryin~ bundle size, e.g.
as in U. S. Patents Nos. 3,091,235; 3,902,880 and 3,913,56~,
the present invention permits the area (cross-sectional size)
of the image carrying bundle to be approximately douhled with
1~ a corresponding increase in image quality. The single or small
multiple fiber used for illumination of the object may be made
of fused silica to permit transmission of ultraviolet light
for ~lourescence studies in either medical or industrial
application. Intense arc lamps, lasers or U.V. sources may
be safely usecl since very little total enercsy can be trans-
mitted to the object (e.g. tissues) under examination.
Thus, the present invention i5 generally defined as
an improvement in an endoscope having a proximal main body
and flexible probe extending rom the main body with flexible
image-conducting and ohject-illuminating means both in the
probe, the improvement comprising the combination of: the
image-conducting means comprising a crreat multip~icity of
juxtapositioned light-conducting fibers affording image-
receiving and image-emitting opposite faces of substanti.al
diametral sizes; the illuminating means comprising a consider-
ably less number of optical fibers than used to make up the
image-conducting means for minimizing the space occupied by
the illuminating means in the probe but affording a corresponding
reduction in intensity of il~umination of objects hy the
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illuminating means; and proximal image intensification means
in the main body for receiving images from the image-emitting
face of the conducting means and displaying the images for
viewing with an intensity increase at least partially
compensating for the reduction of intensity of illumination
of the object.
Details of the invention will become more readily
apparent from the accompanying drawings.
IN THE DRAWIN~,S
Fig. 1 is a schematic, partially cross-sectioned
illustration of a preferred embodiment of the invention
and
Pig. 2 is an enlarged view of the endoscope of
Fig. 1 taken along line 2-2.
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DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to the drawings, endoscope 10 includes a
proximal main body section 12 and flexible probe 14
each encased within respectively preferably rigid and
flexible supports, i.e. sheathings 16 and 18 sho~n
schematically with dot-dash outline.
Supports }6 and 18 are contemplated as being of
any conventional form. U. S. Patents Nos. 3,091,235;
3,698,099 and 3,913,568 are exemplary~ Sheathing 18,
- in particular, may also include means for
articulating the distal end of probe 14 which means may
comprise the arrangement illustrated in U. S. Patent
No. 3,913,568 or that of either of U. S. Patents Mos.
3,091,235 and 3,162,214. In view of~the invention
being applicable to any of the known forms of medical
endoscopes and their industrial counterparts, details
of these instxuments will be omitted.
Referring to the particularities of the present
invention which has an objective of providing very
small illuminating fiber means to permit the image
carrying bundle to be greatly enlarged and/or medical
channelling increased in number or size, the scheme OI
the invention which is diagrammatically illustrated in
the drawings is as follows:
By reduction of the usual great number of illuminztins
fibers to one or two fibers 20 as illustrated, there is
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provided a correspondingly larger free space 22 within
sheath 18 of probe 14. This then becomes available for
enhancement of the performance of other functions of
the endoscope, e.g. enlarging its image-conducting
fiber bundle 24l enlarging a biopsy channel 26 or the
addition of other channelling, e.g. medical catheters
and the like. For example, assuming that the illuminating
fibers 20 (Fig. 2) would normally occupy approximately
the cross-sectional area of image-connecting bundle 24,
the saving of space within sheath 18 by incorporation
of only the two fibers 20 for the above-mentioned
purposes is readily apparent. While the schematic
llustrations of Figs. 1 and 2 show much unused space -
22, it is to be understood that it is this space afforded
by the reduction in number and/or size of illuminating
fibers that is made available for aforesaid improvement
of other functions of the endoscope.
Fibers 20 may be formed of glass or fused silica,
the latter permitting transmission of ultraviolet light
for fluorescence studies in either medical or industrial
applications. Illumination from source 28 may be in
any deslred form including that produced by intense arc
lamps, lasers or high energy U. V. sources sa~ely used
accordlng to the present invention since very little
total energy would be transmitted distally to tissues
in medical applications, for example.
In view of there being an obvious loss of object
illumination by reduction from the usual large number
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of illuminating fibers to the aforesaid one or two
fibers 20, it is contemplated that this loss be co~?ensate~
for with incorporation of an image intensifier 30 at
the proximal end of endoscope 10. The illust--ated
image intensifier 30 is of the fiber optic proximity
focused type, details of which can be had by reference
to U. S. Patents Nos. 3,141,105; 3,321,658 and 3,436,.l~2.
With an object 32 illuminated by ibers 20 and
imaged by objective lenses 34 upon end 36 of riber
bundle 24, the image may be transferred from bundle 24
into fiber optic taper 38 for enlargement prior to
intensification by image intensifier 30 and viewîng
upon face 40 of intensifier 30 with eyepiece lens means
42. Those interested in details of fiber optic tapers
Tnay refer to U. S. Patents Nos. 2,992,516; 2,992,587
and 3,187,627.
An exemplary specific configuration of the system
shown in Figs~ 1 and 2 may include a fiber optic ta?er
(bundle) 38 adaptable to enlarging an image carried by
bundle 24 by a factor of four. The flexible bundle 24
may have an active dlameter of approximately 3 mm so
that the enlarged diameter is approximately 12 mm with
image intensifier 30 having an active aperture of this
latter diameter. With a singl,e fiber siæe for f lexible
bundle 24 being 15 microns ~corresponding to a resolving
power of about 40 line pairs per millimeter), an en-
largement of 4X will reduce the resolution requiremen~
at intensifier 3a to la line pairs per millimeter which
can be readily conventionally transmitted.
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Witl. the aforesaid output image diameter of
approximately 12 mm, an eyepiece magnification of
approximately 5X will meet normal viewing requirements.
It should be understood, however, that the in~ensified
image output at face 40 may be directly coupled to a
television camera or other such means for display on a
monitor (screen).
Those skilled in the art will readily appreciate
that various other modifications and adaptations of the
precise forms of the invention here shown may be made
to suit particular requirements. It is accordingly
intended that all modifications which incorporate the
novel concept disclosed are to be construed as coming
- within the scope of the claims or the range of equiv-
lS ale~_y to wbich they are e~tltled.
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