JP2014226338A - Endoscope - Google Patents

Abstract

PROBLEM TO BE SOLVED: To configure an endoscope which can be easily equipped with a channel even while reducing a diameter.SOLUTION: An endoscope includes: an imaging optical system M (1, 2); an illumination optical system L (4); a channel 5; and a tube 6 surrounding the imaging optical system, the illumination optical system and the channel. In an intracorporeal insertion part including at least a distal end part, the channel comprises a hollow part surrounded by the inner wall face of the tube, the outer wall face of the imaging optical system, and the outer wall faces of the illumination optical system, and the inner wall face of the channel comprises the inner wall face of the tube, the outer wall face of the imaging optical system, and the outer wall faces of the illumination optical system. Thereby, the channel can be configured without disposing a tube for the channel, and a diameter can be reduced.

Description

  The present invention relates to an endoscope that is inserted into a body to observe a living tissue.

An endoscope is used for observing a living tissue inserted into a lumen of a living body. Patent Document 1-2 is given as an example of a document related to an endoscope.
In general, the distal end structure of an endoscope includes a lens that forms an image of an object to be observed, and an imaging element or an imaging fiber such as a CCD (Charge Coupled Device, hereinafter the same) to which the image is input. I can take it. In the case of an image sensor, the image signal converted into an electrical signal by the image sensor is guided outside the body by a transmission cable. It can be displayed and observed on the device.
In addition, illumination is indispensable for an endoscope in order to image the inside of a lumen of a living body. An image incident surface of the imaging optical system and an illumination light exit surface of the illumination optical system are disposed at the distal end portion of the endoscope.
Furthermore, the endoscope is required to have a tunnel-like structure that leads from the proximal end to the distal end, which is called a channel, and the channel is an insertion path for treatment tools such as forceps and a capture net, and a liquid supply / air supply path to the body, Used as a drainage / exhaust passage from the body.

Recently, with the expansion of the scope of application of endoscopes, endoscopes with a small diameter as shown in Patent Document 2 have been developed.
The endoscope described in Patent Document 1 is provided with a channel (“treatment instrument insertion hole 15” in the same document). However, the endoscope described in Patent Document 2 is not suitable for the endoscope having a reduced diameter. In this case, the front end surface is almost occupied by the image incident surface of the imaging optical system and the illumination light exit surface of the illumination optical system, and no channel is provided.

JP 2012-152390 A JP 2003-190077 A

A problem that becomes conspicuous with the reduction in the diameter of an endoscope is that it becomes difficult to mount a channel. When the diameter of the endoscope is reduced, the space in which the illumination optical system and the imaging optical system can be arranged is reduced. In order to observe the observation target with sufficient brightness, the illumination optical system and the imaging optical system are required to be as large as possible. Therefore, it is necessary to mount the parts of the channel portion provided in the conventional endoscope. Impossible or can be implemented, but the size is very limited.
When the channel portion cannot be secured in the endoscope, removal of foreign matters attached to the imaging optical system and liquid feeding or air feeding for securing the field of view cannot be performed, which is inconvenient in the endoscope operation. In addition, since a treatment tool or the like cannot be inserted, operations using the endoscope are limited.
Therefore, a means for inserting a thin endoscope into the catheter and using the gap between the inner diameter of the catheter and the outer diameter of the endoscope to send or supply air is used. Since the entire outer diameter of the catheter tube becomes thick due to the wall thickness of the catheter tube, it is a demerit against the reduction in diameter. In addition, if the main purpose is to reduce the diameter, the gap between the inner diameter of the catheter and the outer diameter of the endoscope needs to be minimized, so that excessive pressure is required at the time of liquid supply / air supply, resulting in poor usability. There is.

  The present invention has been made in view of the above problems in the prior art, and an object of the present invention is to configure an endoscope that can be easily equipped with a channel while reducing the diameter.

An invention according to claim 1 for solving the above-described problem includes an imaging optical system, an illumination optical system, a channel, and a tube surrounding the imaging optical system, the illumination optical system, and the channel. A endoscope,
In the internal insertion portion including at least the distal end portion, the channel is configured by a hollow portion surrounded by the inner wall surface of the tube, the outer wall surface of the imaging optical system, and the outer wall surface of the illumination optical system. The endoscope is characterized in that the inner wall surface comprises the inner wall surface of the tube, the outer wall surface of the imaging optical system, and the outer wall surface of the illumination optical system.

  The invention according to claim 2 is characterized in that all or a part of the illumination optical system and all or a part of the channel are arranged so as to overlap in a circumferential direction centering on a central axis of the endoscope. The endoscope according to claim 1.

  The invention according to claim 3 is characterized in that the imaging optical system is disposed around the central axis of the endoscope, and the imaging optical system is surrounded by the illumination optical system and the channel. The endoscope according to claim 1 or claim 2.

  According to a fourth aspect of the present invention, the imaging optical system is decentered from a central axis of the endoscope, and a part of the imaging optical system, a part of the illumination optical system, and a part of the channel are The endoscope according to claim 1, wherein the endoscope is disposed so as to overlap in a circumferential direction centering on a central axis of the endoscope.

  According to a fifth aspect of the present invention, the imaging optical system includes an imaging fiber, and an outer wall surface of the imaging fiber constitutes an inner wall surface of the channel. The endoscope according to claim 1.

  According to a sixth aspect of the present invention, the imaging optical system includes a cylindrical lens frame that holds a lens at a distal end portion of the imaging fiber, and the outer wall surface of the lens frame and the outer wall surface of the imaging fiber are the channels. The endoscope according to any one of claims 1 to 4, wherein the endoscope has an inner wall surface.

  The invention according to claim 7 is characterized in that the illumination optical system is constituted by a light guide fiber assembly in which a plurality of illumination optical systems are arranged side by side in a circumferential direction centering on a central axis of the imaging optical system. An endoscope according to any one of claims 1 to 6.

  The invention according to claim 8 is characterized in that the illumination optical system is constituted by a cylindrical light guide fiber assembly having a slit extending in a longitudinal direction from an end face disposed on a distal end side of the endoscope. The endoscope according to any one of claims 1 to 7, wherein the channel is configured in a slit, and an inner surface of the slit forms an inner wall surface of the channel.

  The invention according to claim 9 is the endoscope according to claim 8, wherein another tube is connected to the channel formed in the slit on the proximal side from the insertion portion in the body.

  According to a tenth aspect of the present invention, a portion constituting the inner wall surface of the channel of the tube is configured to be expandable and deformable outward so as to expand a cross-sectional area of the channel by pressure from the inside of the channel. The endoscope according to any one of claims 1 to 9, wherein the endoscope is characterized in that it is an endoscope.

  The invention according to claim 11 is characterized in that the outer wall surface of the illumination optical system constituting the inner wall surface of the channel is formed of a concave surface that is concave in the cross section and continuous in the longitudinal direction. The endoscope according to any one of 10.

  According to the present invention, since the channel can be configured without arranging the tube for the channel in the tube surrounding the imaging optical system and the illumination optical system, the channel is equipped while reducing the diameter. Is easy.

It is a longitudinal cross-sectional view of the internal insertion part of the endoscope which concerns on one Embodiment of this invention. FIG. 2 is a detailed view (a) and a cross-sectional view (b) of the tip portion of FIG. 1. FIG. 6 is a longitudinal sectional view (a) and a transverse sectional view (b) of a distal end portion of an endoscope according to another embodiment of the present invention. It is a perspective view showing an example of a light guide fiber applied to the illumination optical system of the endoscope according to an embodiment of the present invention, (a) is a cylindrical, (b) is a cut open Show. It is a perspective view showing an example of a light guide fiber applied to the illumination optical system of the endoscope according to an embodiment of the present invention, (a) is one of the cylindrical one cut in the axial direction, (b) shows two. It is a perspective view which shows an example of the light guide fiber applied to the illumination optical system of the endoscope which concerns on embodiment of this invention. It is a perspective view which shows an example of the light guide fiber applied to the illumination optical system of the endoscope which concerns on embodiment of this invention, (a) is what put two slits in the cylindrical thing, (b ) Shows a slit. FIG. 2 is a longitudinal sectional view (a) and a transverse sectional view (b) showing a branching structure in a proximal end side portion of an endoscope according to an embodiment of the present invention. It is a cross-sectional view of a distal end portion of an endoscope according to another embodiment of the present invention. It is a cross-sectional view of the distal end portion of the endoscope according to another embodiment of the present invention, (a) before the expansion of the cross-sectional area of the channel, (b) of the cross-sectional area of the channel due to the expansion of the outer tube Shown after expansion. 1 is an external view showing an entire system of an example in which an endoscope according to an embodiment of the present invention is combined with a parent endoscope.

  An embodiment of the present invention will be described below with reference to the drawings. The following is one embodiment of the present invention and does not limit the present invention.

The endoscope according to the present embodiment includes an imaging fiber 1, a lens 2 and a lens frame 3 that constitute an imaging optical system M, a light guide fiber 4 that constitutes an illumination optical system L, a channel 5, and an exterior tube 6. Prepare. One structural example is shown in FIGS.
The lens 2 faces the tip surface of the imaging fiber 1 so that the tip of the imaging fiber 1 and the lens 2 are held in the lens frame 3, and the light guide fiber 4 and the channel 5 are arranged outside the imaging fiber 1 and the lens frame 3. Then, the outer tube 6 surrounds them. The lens 2 is a gradient index (GRIN) lens.

As shown in FIG. 2, the imaging optical system M and the outer tube 6 are arranged around the central axis of the endoscope. A fixed interval is formed over the entire circumference between the imaging optical system M and the outer tube 6. The illumination optical system L and the channel 5 are arranged in the circumferential direction at a constant interval between the imaging optical system M and the outer tube 6, and the imaging optical system M is surrounded by the illumination optical system L and the channel 5. It is a configuration.
The illumination optical system L and the channel 5 do not overlap in the radial direction around the central axis AX, and the illumination optical system L and the channel 5 overlap in the circumferential direction around the central axis AX. Therefore, it is advantageous for reducing the diameter of the endoscope. In the structure shown in FIG. 2, all of the illumination optical system L and all of the channels 5 are arranged so as to overlap in the circumferential direction around the central axis AX of the endoscope. The larger the area, the more advantageous is the reduction in the diameter of the endoscope.
The illumination optical system L and the channel 5 are formed with the same thickness (radial dimension) in a range from the outer periphery of the imaging optical system M to the inner periphery of the exterior tube 6 in the radial direction centered on the central axis AX. It can be said that the illumination optical system L and the channel 5 are arranged in different ranges with respect to an angular range centered on the central axis AX, and are arranged in the same range with respect to a radial distance range centered on the central axis AX.

The channel 5 includes a hollow portion surrounded by the inner wall surface of the tube 6, the outer wall surface of the imaging optical system M, and the outer wall surface of the illumination optical system L. In the structure shown in FIGS. 1 and 2, the outer wall surface of the imaging optical system M is composed of the outer wall surface of the imaging fiber 1 and the outer wall surface of the lens frame 3. The inner wall surface of the channel 5 is composed of the inner wall surface of the tube 6, the outer wall surface of the imaging optical system M, and the outer wall surface of the illumination optical system L, and the channel 5 is completed by adjoining these three members without a gap. Yes. The inner wall surface on the inner side (center axis AX side) of the channel 5 with the center axis AX of the endoscope as the center is constituted by the outer wall surface of the imaging optical system M. The lens frame 3 is constituted by the outer wall surface of the lens frame 3 in the axial range, and the outer wall surface of the imaging fiber 1 in the range closer to the base end than the lens frame 3.
As described above, in the gap between the imaging optical system M arranged concentrically and the outer tube 6 surrounding the imaging optical system M, the channel 5 is configured in the same radial distance range as the illumination optical system L, and further for the channel. Since the channel 5 can be configured without arranging the tube, it is easy to equip the channel while reducing the diameter of the endoscope. An endoscope can also be equipped with a channel.
It is sufficient that the channel structure as described above is realized in the in-vivo insertion portion including at least the distal end portion of the endoscope. This is because the proximal end portion which is not inserted into the body is not strictly required to have a small diameter.

Next, another structural example will be described with reference to FIG.
In the structure shown in FIG. 3, the imaging optical system M is arranged decentered from the center axis AX of the endoscope. That is, the central axis AM of the imaging optical system M does not coincide with the central axis AX of the endoscope, and is separated from the central axis AX of the endoscope in the radial direction. With this structure, the gap between the imaging optical system M and the outer tube 6 is maximized on the opposite side of the central axis AM of the imaging optical system M across the central axis AX of the endoscope. The light guide fiber 41 as the illumination optical system L is disposed with a width (circumferential length) that does not completely fill the gap, with the maximum point of the gap as the center. A gap remains on both sides of the light guide fiber 41 along the circumferential direction, and these are defined as channels 51 and 52. The light guide fiber 41 is formed by binding and bundling a plurality of optical fibers 41 a having a large wire diameter with a sealing material 42.
In such a structure, a part of the imaging optical system M, a part of the illumination optical system L, and a part of the channels 51 and 52 are arranged so as to overlap in the circumferential direction centering on the central axis AX of the endoscope. Therefore, it is easy to equip the channel while further reducing the diameter of the endoscope.

  As described above, the illumination optical system L is a light guide fiber assembly in which a plurality of light guide fibers are arranged in the circumferential direction around the central axis AM (common to AX in FIG. 2) of the imaging optical system M. Composed by the body.

Here, a manufacturing method of the channel 5 will be described with reference to FIG. The light guide fiber 4 shown in FIG. 4A is a light guide fiber assembly in which a bundle of thin optical fibers is formed in a cylindrical shape. The light guide fiber 4 is split by one notch along the axial direction, and is cut open as shown in FIG. 4 (b). The imaging fiber 1 and the lens frame 3 (the lens 2 are already provided) having an outer diameter slightly larger than the inner diameter of the light guide fiber 4 in the state shown in FIG. When inserted into the fiber 4, the outer diameter of the light guide fiber 4 swells and a gap is formed in the opened portion. Further, when the exterior tube 6 is externally provided on the outside of the light guide fiber 4, an endoscope equipped with the channel 5 shown in FIG. 2 is obtained.
By simply inserting the imaging optical system M into the hollow portion of the light guide fiber 4 opened at one place as described above, a gap constituting the channel 5 is automatically formed, and the subsequent process is simply covered with the outer tube 6. Can be produced. Therefore, one of the advantages of this structure is that it is very easy to assemble.

Further, as shown in FIG. 5, the channel 5 can be provided in the endoscope even if one or a plurality of light guide fibers 4 obtained by cutting a cylindrical one in the axial direction are applied. For example, as shown in FIG. 5A, a light guide fiber 4 corresponding to a central angle of 180 degrees in a cylindrical shape is applied. In this way, the channel 5 having a wider flow path cross-sectional area can be provided. The circumferential width of the channel 5 can be selected by selecting how many minutes are used with respect to 360 degrees of the circumference of the cylindrical shape.
Further, by applying two such cuts as shown in FIG. 5B, two channels 5 can be provided.

  Further, as shown in FIG. 6, a light guide fiber assembly in which a plurality of optical fibers 41a having a large wire diameter are used side by side and constrained and coupled may be applied. By using this configuration, an endoscope having the structure shown in FIG. 3 is obtained.

Further, as shown in FIG. 7, the light guide fiber 4 as the illumination optical system L is a cylindrical light guide fiber having a slit S extending in the longitudinal direction from an end face 4a disposed on the distal end side of the endoscope. Aggregates can be applied. Unlike what was shown in FIG.4 (b), it is not completely cut open but the cylindrical part 4b remains on the base end side.
A plurality of slits S may be provided as shown in FIG. By doing so, a plurality of channels 5 can be provided in the endoscope.

  By providing a plurality of channels 5 (51, 52), in addition to functions such as liquid feeding, a function of inserting a guide wire, a treatment instrument, etc. can be provided as a function of these simultaneously. Therefore, workability and functionality are improved.

When the light guide fiber 4 having the slit S and the cylindrical portion 4b shown in FIG. 7 is applied, a structural example on the base end side is shown in FIG. For the sake of simplicity, a case where the light guide fiber 4 having one slit S shown in FIG.
As shown in FIG. 8, the imaging fiber 1, the light guide fiber 4 having the structure shown in FIG. 7B, and the outer tube 6 are placed inside the outer pipe 7 so that the proximal end portion of the outer tube 6 is held. Insert into. The end portion of the slit S is exposed from the outer tube 6 and the outer pipe 7 to the base end side.
The tube 8 is inserted into the slit S inside the outer pipe 7 from the base end side of the outer pipe 7. Next, when the adhesive 9 is filled and fixed in the gap in the surrounding pipe 7 remaining on both sides of the inserted tube 8, a hollow structure connected from the hollow portion of the tube 8 to the channel 5 is completed. The channel 5 is formed in the slit S, and the inner side surface Sa of the slit S forms the inner wall surface of the channel 5. A tube 8 connects to the channel 5 formed in the slit S. Through the tube 8 and the channel 5, liquid feeding and air feeding, a guide wire and a treatment instrument can be inserted into the distal end of the endoscope.
As described above, the connection portion between the channel 5 and the tube 8 can be configured. This connection part is comprised in the part of a base end side rather than a body insertion part.

  Further, as shown in FIG. 8, the imaging fiber 1 and the ride guide fiber 4 can be branched by extending the imaging fiber 1 from the ride guide fiber 4 through the slit S. When the imaging fiber 1 and the light guide fiber 4 are branched in this way, the illumination optical system L and the imaging optical system M can be separated, so that it is easy to provide a light shielding measure between the optical systems. Effects such as good assembling of the lens of the optical system and the like are exhibited.

As shown in FIG. 9, the split surface of the light guide fiber 4, the outer peripheral wall surface of the lens frame 3, and the outer tube so that the cross-sectional shape of the channel 5 is round (including circular, rounded, and elliptical). A portion of the inner peripheral wall surface 6 that constitutes the inner wall surface of the channel 5 may be processed.
When a guide wire, a treatment instrument, or the like is inserted into the channel 5, the most efficient shape is a circle. By processing the shape of the channel 5 so that the treatment instrument desired to be inserted can be smoothly inserted, an endoscope is provided. The insertability can be improved while maintaining the small diameter.
Therefore, the outer wall surface of the illumination optical system L (light guide fiber 4) that forms the inner wall surface of the channel 5 is a concave surface that is concave and continuous in the longitudinal direction. The outer wall surface of the imaging optical system M constituting the inner wall surface of the channel 5 is normally a convex cylindrical outer surface, but it may be processed into a flat surface or a concave concave surface that is continuous in the longitudinal direction. Since the outer wall surface of the outer tube 6 constituting the inner wall surface of the channel 5 is usually a concave cylindrical inner surface, it may be left as it is or may be processed to be further recessed.

As shown in FIG. 10, the portion 6 a constituting the inner wall surface of the channel 5 of the outer tube 6 is configured to be inflatable and deformable outward so as to enlarge the cross-sectional area of the channel 5 by the pressure from the inside of the channel 5. Can be implemented. The pressure from the inside of the channel 5 that expands the portion 6 a is a pressure by the fluid 10 that is fed or sent into the channel 5 and a pressing force from a solid object such as a treatment instrument that is inserted into the channel 5. .
Making the portion 6 a inflatable can be easily achieved by applying a highly elastic or plastic material to the outer tube 6. Alternatively, the portion 6a may be configured to have a slack in advance and be stretched by an internal pressure.

  By using such an expansion function of the portion 6a, the cross-sectional area of the channel 5 is temporarily increased as shown in FIGS. 10 (a) to 10 (b) by the pressure applied to the channel 5 during liquid feeding or air feeding. The liquid or gas can be sent from the proximal end portion of the endoscope to the distal end portion with a small force. In addition, when inserting the endoscope into the body, the insertion work can be performed with a minimum diameter, and a treatment instrument having a relatively large diameter can be inserted through the channel 5 while increasing the diameter of the channel 5 near the observation affected part. Improvements in workability, expansion of types of treatment tools that can be applied, and the like are achieved.

Next, the configuration and usage of the entire system including peripheral devices will be described using the configuration shown in FIG. 11 as an example.
The in-vivo insertion portion A1 including the distal end portion of the endoscope described with reference to FIGS. 1 to 10 is inserted into the channel of the parent endoscope B as shown in FIG.
In the branching part A2, for example, the imaging optical system M and the illumination optical system L are branched from the tube for feeding liquid, air feeding, and the treatment instrument by the structure shown in FIG. 8, and the former is an eyepiece unit through the tube A3. The latter is connected to A4, the latter being connected to the tube A5, for example to the syringe A6. The branch structure of the imaging optical system M and the illumination optical system L shown in FIG. 8 can be arranged in the eyepiece unit A4.
The eyepiece unit A4 includes an illumination light source connected to the illumination optical system L and an observation eyepiece or electronic camera connected to the imaging optical system M, and has a function for obtaining an image to be observed. It is equipped.
The syringe A6 may be either for liquid feeding or for air feeding. By extruding the syringe, the liquid or gas filled in the syringe is sent to the distal end portion of the body insertion portion A1.

  As in the system configuration example shown in FIG. 11, the endoscope according to the present embodiment may be used by combining an endoscope of another product as the parent endoscope B. By inserting the endoscope insertion portion A1 of the endoscope of the present embodiment into the channel of the parent endoscope B, insertion into the body is performed by the guidance of the parent endoscope B, and insertion is impossible with the parent endoscope B It is possible to observe the inside by inserting the in-vivo insertion portion A1 into a small-diameter site such as in the oviduct, bile duct, or pancreatic duct.

  In the above embodiment, the imaging optical system M is configured by the imaging fiber 1 and the lens 2. However, the imaging optical system M is configured by an imaging element such as a CCD and a lens, and this imaging element is an endoscope together with the lens. You may equip with the tip part of.

DESCRIPTION OF SYMBOLS 1 Imaging fiber 2 Lens 3 Lens frame 4 Light guide fiber 5 Channel 6 Exterior tube 7 Outer pipe 41 Light guide fiber 51, 52 Channel L Illumination optical system M Imaging optical system S Slit

Claims (11)

An endoscope comprising an imaging optical system, an illumination optical system, a channel, and a tube surrounding the imaging optical system, the illumination optical system, and the channel,
In the internal insertion portion including at least the distal end portion, the channel is configured by a hollow portion surrounded by the inner wall surface of the tube, the outer wall surface of the imaging optical system, and the outer wall surface of the illumination optical system. An endoscope comprising: an inner wall surface of the tube; an outer wall surface of the imaging optical system; and an outer wall surface of the illumination optical system.   2. The inner part of claim 1, wherein all or part of the illumination optical system and all or part of the channel are arranged so as to overlap in a circumferential direction centering on a central axis of the endoscope. Endoscope.   3. The imaging optical system according to claim 1, wherein the imaging optical system is disposed around a central axis of the endoscope, and the imaging optical system is surrounded by the illumination optical system and the channel. Endoscope.   The imaging optical system is decentered from the central axis of the endoscope, and a part of the imaging optical system, a part of the illumination optical system, and a part of the channel are centered on the central axis of the endoscope The endoscope according to claim 1, wherein the endoscope is arranged so as to overlap in the circumferential direction.   The endoscope according to any one of claims 1 to 4, wherein the imaging optical system includes an imaging fiber, and an outer wall surface of the imaging fiber constitutes an inner wall surface of the channel. .   The imaging optical system has a cylindrical lens frame that holds a lens at the tip of the imaging fiber, and the outer wall surface of the lens frame and the outer wall surface of the imaging fiber constitute the inner wall surface of the channel. The endoscope according to any one of claims 1 to 4, wherein the endoscope is characterized.   7. The illumination optical system is constituted by a light guide fiber assembly in which a plurality of illumination optical systems are arranged side by side in a circumferential direction centering on a central axis of the imaging optical system. The endoscope according to any one of the above.   The illumination optical system is configured by a cylindrical light guide fiber assembly having a slit extending in a longitudinal direction from an end surface disposed on the distal end side of the endoscope, and the channel is configured in the slit. The endoscope according to any one of claims 1 to 7, wherein an inner side surface of the slit constitutes an inner wall surface of the channel.   The endoscope according to claim 8, wherein another tube is connected to the channel formed in the slit on a proximal end side from the in-vivo insertion portion.   The part which comprises the inner wall face of the said channel of the said tube was comprised so that expansion deformation could be carried out outside so that the cross-sectional area of the said channel might be expanded with the pressure from the inside of the said channel. The endoscope according to any one of Items 9.   The outer wall surface of the illumination optical system constituting the inner wall surface of the channel is formed of a concave surface having a concave shape in the cross section and continuing in the longitudinal direction. Endoscope.

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