JPH10178A - Adapter for illumination light transmission system of endoscope device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an adapter for an illumination light transmission system, which ensures improvement of the photo-quantity distribution even though the diameter of an optical fiber bundle on the endoscope side is not small. SOLUTION: The emission side end of the first optical fiber bundle 25 passing a light guide cord is held by the first holding cylinder 23, while the incident side end part of the second optical fiber bundle 35 passing an endoscope is held by the second holding cylinder 34. An adapter 50 is composed of a body 51 and a light guide 55, and the body 51 is coupled removably with the first and second cylinders 23 and 34. The light guide 55 is tapered so that the diameter lessens from the base end toward the foremost, and the base end face 55x has the same diameter as the emissive end face 25x of the first optical fiber bundle 25 and makes substantial contacting therewith, while the foremost end face 55y has a smaller diameter than the emissive end face 35x of the second optical fiber bundle 35 and is situated apart from this end face.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an adapter for connecting an endoscope and a light guide cord in a separated endoscope apparatus.

[0002]

2. Description of the Related Art An endoscope apparatus in which a light guide cord to be connected to a light source and an endoscope are separated is known. In such an endoscope apparatus, since a plurality of endoscopes can be sequentially connected to one light guide cord and used, the cost of the entire apparatus can be reduced. In such an endoscope apparatus, an adapter for connecting the light guide cord to the endoscope is disclosed in Japanese Patent Application Laid-Open Nos. 2-114226 and 53-5645.

[0003] The adapter of the former publication is constructed by incorporating a lens system in a tubular adapter body. A first holding tube and a second holding member for holding the first optical fiber bundle passing through the light guide cord at the exit side end thereof and the second optical fiber bundle passing through the endoscope at the incident side end thereof in a circular cross section. A tube is attached, these first,
Both ends of the adapter body are detachably connected to the second holding cylinder by means such as screwing. Illumination light from the light source exits from the exit end face of the first optical fiber bundle, and is transmitted through the lens system to the entrance end face of the second optical fiber bundle on the endoscope side. In this adapter, the lens system is exchanged or moved according to the cross-sectional area of the first and second optical fibers in order to transmit the illumination light efficiently.

The adapter disclosed in the latter publication includes a light guide member (made of a tapered fiber bundle, a tapered rod, or the like) having a tapered shape with a circular cross section. The proximal end face of the light guide member has the same diameter as the exit end face of the first optical fiber bundle on the light source side, and is in contact with the exit end face. The distal end surface of the light guide member has the same diameter as the incident end surface of the second optical fiber bundle on the endoscope side, and is in contact with this incident end surface. The light guide member is held by a tapered tubular adapter body. The adapter body is connected to the output end of the first optical fiber bundle and the incident end of the second optical fiber bundle. This publication does not disclose the state in detail.

[0005]

By the way, the illumination light incident on the incident end face of the first optical fiber bundle from the light source is the first light.
Generally, the smaller the angle of incidence of the optical fiber bundle with respect to the axis, the larger the amount of light, and the larger the angle, the smaller the amount of light. Due to the characteristics of the optical fiber bundle, such a light amount distribution (light distribution characteristic) of the illumination light similarly appears on the emission side of the first optical fiber bundle. If the first optical fiber bundle and the second optical fiber bundle have the same diameter and the exit end surface of the first optical fiber bundle and the incident end surface of the second optical fiber bundle are in direct contact, the exit end surface of the second optical fiber bundle The illumination light emitted from through the illumination window of the endoscope has the same light amount distribution (see curve A in FIG. 3). In the case of such a light amount distribution, the observation target is too bright at a portion near the center of the irradiation range of the illumination light, and too dark at a portion far from the center (peripheral portion). Therefore, it is required to equalize or reduce the light amount distribution.

When the adapter disclosed in the above publication is used, the light quantity distribution changes, but this cannot always be changed to a preferable one. That is, in the adapter of the former publication, the coupling lens system is exchanged or moved according to the diameter of the exit end face of the first optical fiber bundle and the diameter of the entrance end face of the second optical fiber bundle, thereby transmitting the illumination light with little loss. However, the result does not necessarily lead to an improvement in the light amount distribution. In the adapter disclosed in the latter publication, a light guide member having a taper is used, so that an improvement in the light amount distribution is expected. However, both end faces of the light guide member are in contact with the emission end face of the first optical fiber bundle and the incidence end face of the second optical fiber bundle, and the taper of the light guide member is determined depending on the diameter of these optical fiber bundles. The light quantity distribution can be improved only when the diameter of the input end face of the second tapered fiber bundle is sufficiently smaller than the diameter of the output end face of the first tapered fiber bundle. If this condition is not satisfied, the light quantity distribution is improved. Can not do.

[0007]

According to a first aspect of the present invention, there is provided a first optical fiber bundle which passes through a light guide cord to be connected to a light source and has an emission end portion having a circular cross section by a first holding cylinder. And an adapter for connecting the second optical fiber bundle, which passes through the endoscope and whose end on the incident side has a circular cross section by the second holding cylinder,
Both ends are connected to the first holding cylinder and the second holding cylinder, and a cylindrical adapter body detachably attached to at least one of the first and second holding cylinders; and the first and second optical fiber bundles provided in the adapter body. Having a light guide member that is arranged between the ends and is coaxial with these ends,
The light guide member has a tapered shape in which the cross section is circular and the diameter decreases from the base end to the front end, and the base end surface has substantially the same diameter as the exit end surface of the first optical fiber bundle. And the distal end surface thereof is smaller in diameter than the incident end surface of the second optical fiber bundle and is separated from the incident end surface.

According to a second aspect of the present invention, in the illumination light transmission system adapter of the endoscope apparatus according to the first aspect, the adapter main body is connected to the first holding cylinder to house and support the light guide member. And a control cylinder connected to one of the second holding cylinder and the support cylinder so as to be rotatable and immovable in the axial direction and to be screwed to the other. The distance between the distal end surface of the light guide member and the incident end surface of the second optical fiber bundle is adjusted with the rotation of the tube. According to a third aspect of the present invention, in the illumination light transmission system adapter in the endoscope apparatus according to the second aspect, the adapter body further has a mounting cylinder, and the mounting cylinder is detachably attached to the second holding cylinder. The adjusting cylinder is connected to the mounting cylinder such that the adjusting cylinder is rotatable and cannot move in the axial direction, so that the adjusting cylinder and the second holding cylinder are connected to each other. It is characterized by being detachably connected to the cylinder. The invention of claim 4 is the invention of claim 2 or 3
In the illumination light transmission system adapter in the endoscope device according to the above, a male screw portion is formed on the outer periphery of the support tube, and a female screw portion to be screwed to the male screw portion is formed on the inner periphery of the adjustment tube. A rubber ring is attached to one of the outer periphery of these support cylinders and the inner periphery of the adjustment cylinder in an axial direction away from the screw portion, and to the other is an annular ring in which the rubber ring abuts in an elastically deformed state. A contact surface is formed.

According to a fifth aspect of the present invention, in the illumination light transmission system adapter according to the first aspect of the present invention, both ends of the adapter main body are detachably connected to the first and second holding cylinders. It is characterized by being performed. According to a sixth aspect of the present invention, in the illumination light transmission system adapter in the endoscope apparatus according to the first aspect, the adapter body is connected to the first holding cylinder and houses and supports the light guide member. And a mounting cylinder detachably connected to the second holding cylinder, wherein the support cylinder and the mounting cylinder are detachably connected by screwing.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a first embodiment of the present invention will be described.
A description will be given based on FIGS. First, a schematic configuration of the endoscope apparatus will be described mainly with reference to FIG. This endoscope device includes a light source device 10, a light guide cord 20,
And a rigid endoscope 30. The light source device 10 is configured by housing a light source 12 and a concave mirror 13 (convergence means) for converging light from the light source 12 in a housing 11.

The light guide cord 20 includes a flexible tube 21, a sleeve-shaped optical connector 22 attached to the base end of the tube 21, and a tube 2.
Holding tube 23 (first holding tube) attached to the tip of 1
And the first optical fiber bundle 2 housed in the tube 21
5 (see FIG. 1). First optical fiber bundle 2
The base end (incident end) and the distal end (outgoing end) of No. 5 are inserted and held in the optical connector 22 and the holding tube 23, respectively, in a circular cross section. The base end face (incident end face) of the first optical fiber bundle 25 coincides with the base end of the optical connector 22, and receives the converged illumination light from the concave mirror 13 with the optical connector 22 inserted into the housing 11. It has become. As shown in FIG. 1, the tip end face 25x (the emission end face) of the first optical fiber bundle 25 coincides with the tip end of the holding cylinder 23. The holding cylinder 23 has a small outer diameter at the distal end, and has a male screw portion 23a formed on the outer peripheral surface thereof.

The endoscope 30 has a main body 31, an elongated rigid insertion portion 32 extending forward from the main body 31, and an eyepiece 33 provided at the rear end of the main body 31. A surface that is oblique to the axis of the insertion portion 32 is formed at the distal end, and an observation window and an illumination window (both not shown) are formed on this surface. The distal end of the insertion section 32 has a built-in objective optical system facing the observation window.
The objective optical system is connected to the eyepiece 3 via an image transmission optical system.
3 is optically connected. In addition, the lighting window has a second
The front end surface (outgoing end surface) of the optical fiber bundle 35 faces each other. The second optical fiber bundle 35 passes through the insertion portion 32 and the main body 31, and a base end (incident end) thereof is led out of the main body 31. The main body 31 includes the insertion portion 3
The holding cylinder 34 is attached orthogonally to the holding cylinder 34. FIG.
As shown in the figure, the incident end of the second optical fiber bundle 35 is
It is inserted and held in the holding cylinder 34 with a circular cross section. The base end face 35x (incident end face) of the second optical fiber bundle 35 coincides with the outer end of the holding tube 34.

The endoscope apparatus further optically connects the exit end of the first optical fiber bundle 25 of the light guide cord 20 and the entrance end of the second optical fiber bundle 35 of the endoscope 30. An adapter 50 is provided. The adapter 50 includes a tubular adapter body 51 and a light guide member 5 provided in the adapter body 51.
5 (see FIG. 1). The adapter body 51 has three tubes, namely, a support tube 52 detachably connected to the holding tube 23 of the light guide cord 20 and a mounting tube 53 detachably connected to the holding tube 34 of the endoscope 30.
And an adjusting cylinder 54 for connecting the supporting cylinder 52 and the mounting cylinder 53 to each other.

Next, the configuration of the adapter 50 will be described in detail with reference to FIG. The support tube 52 has a base end,
The outer diameter becomes smaller in the order of the middle part and the tip part. The support cylinder 52 and the adjustment cylinder 54 are connected by screwing a male screw part 52 a formed on the outer periphery of the distal end of the support cylinder 52 and a female screw part 54 a formed on the inner circumference of the middle part of the adjustment cylinder 54. An annular groove 52b is formed on the outer periphery of the intermediate portion of the support cylinder 52, and a rubber ring 56 is mounted in the groove 52b. The inner peripheral surface at the rear end of the adjusting cylinder 54 is an annular abutting surface 54b that comes into contact with the rubber ring 56 in an elastically deformed state when screwed with the supporting cylinder 52.

The front end of the adjusting cylinder 54 and the rear end of the mounting cylinder 53 are connected by a C-shaped snap ring 57. The snap ring 57 is connected to the adjusting cylinder 54
The adjusting cylinder 54 is rotatably and axially immovably connected to the mounting cylinder 53 with respect to the mounting cylinder 53. Have been.

An auxiliary cylinder 58 is inserted and fixed inside the distal end of the support cylinder 51. The inner peripheral surface of the auxiliary cylinder 58 is tapered, so that the cross section of the internal space has a smaller diameter toward the tip while maintaining a circular shape. The light guide member 55 is housed and fixed to the auxiliary cylinder 58. This light guide member 55 includes a tapered fiber bundle, that is, a large number of tapered fibers 55.
The outer peripheral surface of the auxiliary cylinder 58 has a taper that matches the inner peripheral surface of the auxiliary cylinder 58. That is, the light guide member 55 gradually decreases in diameter from the base end to the distal end while maintaining a circular cross section. The distal end face 55y of the light guide member 55 coincides with the distal ends of the auxiliary cylinder 58 and the support cylinder 51.

The base end face 55x of the light guide member 55
And the diameter of the exit end face 25x of the first optical fiber bundle 25 are equal. Further, the diameter of the distal end face 55x of the light guide member 55 is smaller than the diameter of the incident end face 55x of the second optical fiber bundle 35.

As described above, the adapter 50 includes the support cylinder 52, the mounting cylinder 53, the adjustment cylinder 54, and the light guide member 5.
5 as an assembly. This adapter 50 is used to hold the holding tube 23 of the light guide cord 20.
It is detachably connected to. More specifically, the holding cylinder 2 is provided on the inner periphery of the base end of the support cylinder 52 of the adapter 50.
A female screw part 52c that is screwed to the third male screw part 23a is formed. By advancing the screwing between the screw portions 52c and 23a and tightening the base end surface of the support tube 52 until it hits the annular step 23b formed in the middle portion of the holding tube 23,
The support member 52 is detachably connected to the holding cylinder 23 while being accurately positioned. In this connection state, the base end face 55x of the light guide member 55 is substantially in surface contact with the emission end face 25x of the first optical fiber bundle 25.
That is, they are actually in contact with each other or confront each other via a very small gap.

The adapter 50 attached to the holding tube 23 of the light guide cord 20 as described above is detachably connected to the holding tube 34 of the endoscope 30 by a locking mechanism 60 in a one-touch manner. Hereinafter, the configuration of the locking mechanism 60 will be described in detail. The distal end of the mounting tube 53 of the adapter 50 is made thicker by increasing its outer diameter, and a slit 61 penetrating in the radial direction is formed here. A locking plate 62 orthogonal to the axis of the mounting cylinder 53 is slidably inserted into the slit 61. The locking plate 62 has an insertion hole 62a. In FIG. 1, the upper edge and the lower edge of the insertion hole 62a form a semicircle having a diameter slightly larger than the outer diameter of the holding cylinder 34, and both side edges form a short straight line. The distance between the two side edges, that is, the width of the insertion hole 62 a is slightly larger than the outer diameter of the holding cylinder 34. The lower edge of the locking plate 62 forms an arc concentric with the lower edge of the insertion hole 62a. Both side edges of the locking plate 62 form a straight line parallel to both side edges of the insertion hole 62a. At the outer end (upper end in FIG. 1) of the locking plate 62, a pressing portion 62b bent at a right angle is formed.

An accommodation space 63 is formed at the tip of the mounting cylinder 53 so as to be continuous with the slit 61 and located on the opposite side of the pressing portion 62b. In this storage space 63,
A spring 64 that urges the locking plate 62 in a direction to protrude from the mounting cylinder 53 is housed. This accommodation space 63
It is closed by an arc-shaped cover 65. The cover 65 is fixed to the mounting cylinder 53 by a set screw 66.

When the adapter 50 is attached to the holding tube 34 of the endoscope 30 using the locking mechanism 60 having the above-described structure,
Push the adapter 50 toward the holding tube 34, and
The third holding cylinder 34 is inserted. When the tapered surface 34 a at the tip of the holding cylinder 34 hits the lower edge of the insertion hole 62 a of the locking plate 62, the locking plate 62 is moved to the unlocked position against the spring 64. When the holding cylinder 34 further advances in this state, the lower edge of the locking plate 62 pressed by the spring 64 fits into the annular locking groove 67 formed at a predetermined distance from the tip of the outer circumference of the holding cylinder 34. The locking plate 62 returns to the locked position. In this manner, the adapter 50 can be held in one-touch with the holding cylinder 34.
Linked to When removing the adapter 50 from the holding tube 34, the pressing portion 62a of the locking plate 62 is pressed to set the locking plate 62 to the unlocked position, and then the adapter 50 is retracted from the holding tube 34. As a result, the holding cylinder 34 is pulled out of the mounting cylinder 53, and the connected state is released. As described above, the adapter 50 can be easily attached to and detached from the endoscope 30, and the endoscope 30 can be easily replaced.

As described above, when the light guide cord 20 and the endoscope 30 are connected via the adapter 50, the light guide member 55 is connected to the first optical fiber bundle 25.
Of the second optical fiber bundle 35 and the light guide member 55 are coaxial. Normally, the distal end face 55y of the light guide member 55 is connected to the incident end face 35x of the second optical fiber bundle 35.
Away from

The illumination light from the light source 12 is reflected by the concave mirror 13 and is incident on the incident end face of the first optical fiber bundle 25, passes through the first optical fiber bundle 25, and exits from the exit end face 2 thereof.
From 5x, the light enters the base end face 55x of the light guide member 55. As described above, the light amount distribution of the illumination light emitted from the emission end face 25x of the first optical fiber bundle 25 is large near the central axis, decreases when the distance from the central axis increases, and decreases without passing through the light guide member 55. Through the optical fiber 35,
When the light is emitted from the illumination window, it is as shown by a curve A in FIG. However, in this embodiment, since the light passes through the light guide member 55, the light amount distribution of the illumination light emitted from the illumination window is
This is improved and equalized or reduced as shown by the curve B in FIG.

The reason for the improvement of the light quantity distribution will be described. Many tapered fibers 5 constituting the light guide member 55
Each of 5a reflects the illumination light on its tapered surface. Illumination light incident at a small angle with respect to the central axis increases its angle with respect to the central axis due to reflection on the tapered surface. As a result, the illumination light in the vicinity of the central axis is dispersed to the peripheral portion, and the light amount distribution is improved.

In the adapter 50, by turning the adjusting cylinder 54, the position of the supporting cylinder 52 with respect to the holding cylinder 34, in other words, the distal end face 55y of the light guide member 55, is formed by the screwing action of the threaded portions 52a, 54a. The distance H between the incident end surface 35x of the second optical fiber bundle 35 and the leading end surface 55y of the light guide member 55 is adjusted.
The spread area of the luminous flux of the illumination light emitted from the optical fiber bundle 35 can be made equal to the area of the incident end face 35x of the second optical fiber bundle 35. That is, the distal end surface 55 of the light guide member 55
Almost all of the illuminating light emitted from y can be made incident on the incident end face 35x of the second optical fiber bundle 35 to minimize the transmission loss and to reduce the first optical fiber bundle 25.
The illumination light can be transmitted from the optical fiber bundle to the second optical fiber bundle 35. Each time the endoscope 30 is replaced, the distance H is adjusted according to the diameter of the second optical fiber bundle 35. The rubber ring 56 attached to the support cylinder 52 is in contact with the contact surface 54b of the adjustment cylinder 54 in an elastically deformed state, and the friction between the two prevents the unnecessary rotation of the adjustment cylinder 54. it can.

As is clear from the above description, in the adapter 50 of this embodiment, the distal end face 55y of the light guide member 55 is separated from the incident end face 35x of the second optical fiber bundle 35, and the spread of the illumination light from this distal end face 55y. Is used to reduce the taper angle of the light guide member 55,
Can be large enough. This is because even if the diameter of the incident side end of the second optical fiber bundle 35 is relatively large, the diameter of the distal end face 55y of the light guide member 55 can be reduced without depending on the diameter of the incident end. is there.
As described above, the taper angle of the light guide member 55 can be made sufficiently large irrespective of the diameter of the incident side end of the second optical fiber bundle 35. Improvements can be made.

In this embodiment, the light guide member 55
Can also be used when the diameter of the tip end face 55y of the first optical fiber bundle 35 and the diameter of the incident end face 35x of the first optical fiber bundle 35 are equal. In this case, the tip end surface 55y and the incident end surface 35x are brought into surface contact by the rotating operation of the adjusting cylinder 54.

The adapter 50 of the present embodiment is not only detachable from the holding tube 34 on the endoscope side by the locking mechanism 60 but also attached to the holding tube 23 by screwing the screw portions 23a and 52c. Is also removable. Therefore, adapter 50 having light guide members 55 with different taper angles
It is also possible to change the characteristic of the light amount distribution by replacing the above.

In the above embodiment, the adjusting cylinder may be directly connected to the holding cylinder in a detachable manner, and may be rotatable with respect to the holding cylinder and cannot be moved in the axial direction. The first holding cylinder and the support cylinder of the adapter may be integrated.

FIG. 4 shows a second embodiment. In this embodiment, components corresponding to those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted. The adapter body 51A of the adapter 50A of the present embodiment is
And the mounting cylinder 53A, and does not include the adjusting cylinder of the first embodiment. The attachment tube 53A is formed longer than in the first embodiment, and is formed by screwing a female screw portion 59 formed on the inner periphery of the intermediate portion to a male screw portion 52a formed on the outer periphery of the distal end portion of the support tube 52. And both are detachably connected. It should be noted that one end is positioned relative to the other end by the base end surface of the mounting tube 53A hitting an annular step 52d formed on the outer periphery of the intermediate portion of the support tube 52.

When connecting different endoscopes, if the diameter is different from the second optical fiber bundle 35 of the endoscope used before, the distal end face 55y of the light guide member 55 and the incident end face of the second optical fiber bundle 35 are used. The distance H between the second optical fiber bundle 35 and the adapter 50A corresponding to the diameter of the second optical fiber bundle 35 is replaced. Thereby, the spread range of the illumination light from the front end face 55y is made to coincide with the incident end face 35x. In this case, the distance H may be changed by replacing the mounting tube 53A with a different length or the supporting tube 52 with a different length.

In the first and second embodiments, as shown in FIG. 5, a single taper rod made of a transparent material such as glass is used instead of the light guide member 55 made of a bundle of tapered fibers 55a. The light guide member 55A may be used. The present invention improves the light quantity distribution of the illumination light incident on the first optical fiber bundle not only when the central portion is large and the peripheral portion is small but also when the central portion is small and the intermediate portion is large and the peripheral portion is small. be able to. As the endoscope, not only a rigid endoscope but also a flexible endoscope can be used.

[0033]

According to the adapter of the first aspect of the present invention,
Even if the diameter of the incident side end of the second optical fiber bundle is not sufficiently small compared to the diameter of the exit end of the first optical fiber bundle, the distal end surface of the light guide member is separated from the incident end surface of the second optical fiber bundle. By utilizing the spread of the illumination light from the front end surface, the taper angle of the light guide member can be made sufficiently large, and the light quantity distribution of the illumination light can be improved. According to the second aspect of the present invention, the distance between the distal end surface of the light guide member and the incident end surface of the second optical fiber bundle can be adjusted by rotating the adjusting cylinder, and the spread range of the illumination light from this distal end surface can be adjusted. The incident end face of the two optical fiber bundles can be made coincident with each other, and transmission loss of illumination light can be easily minimized. Claim 3
According to the invention, the adapter body is detachably connected to the second holding tube on the endoscope side, and the supporting tube is detachably connected to the first holding tube on the light guide cord side.
An adjusting cylinder for adjusting the distance is provided, and each cylinder is provided with a function. Therefore, the configuration of each cylinder can be simplified. In addition, since the support cylinder supporting the light guide member is replaceable, the light amount distribution can be changed. According to the fourth aspect of the invention, unnecessary rotation of the adjusting cylinder can be prevented by the rubber ring, and the adjusted distance between the distal end surface of the light guide member and the incident end surface of the second optical fiber bundle is reliably maintained. can do. According to the fifth aspect of the present invention, the adapter is replaced such that the distance between the distal end surface of the light guide member and the incident end surface of the second optical fiber bundle corresponds to the diameter of the incident end surface of the second optical fiber bundle.
The range of spread of the illumination light from the front end surface can be matched with the incident end surface of the second optical fiber bundle, and the transmission loss of the illumination light can be easily minimized. According to the invention of claim 6, by exchanging the mounting cylinder such that the distance between the distal end face of the light guide member and the incident end face of the second optical fiber bundle corresponds to the diameter of the incident end face of the second optical fiber bundle, The spread range of the illumination light from the distal end surface can be matched with the incident end surface of the second optical fiber bundle, and the transmission loss of the illumination light can be easily minimized.

[Brief description of the drawings]

FIG. 1 is a sectional view of a main part of an adapter according to a first embodiment of the present invention.

FIG. 2 is an overall configuration diagram of the endoscope apparatus including the adapter according to the first embodiment of the present invention.

FIG. 3 is a diagram showing a comparison with a case where the light amount distribution when the adapter of the present invention is used is not used.

FIG. 4 is a sectional view of a main part of an adapter according to a second embodiment of the present invention.

FIG. 5 is a sectional view showing another light guide member that can be used in the first and second embodiments.

[Explanation of symbols]

 Reference Signs List 10 light source 20 light guide cord 23 first holding tube 25 first optical fiber bundle 25x emission end face 30 endoscope 34 second holding tube 35 second optical fiber bundle 35x incidence end surface 50 adapter 51 adapter body 52 support cylinder 52a male screw section 53, 53A Mounting tube 54 Adjusting tube 54a Female screw portion 54b Contact surface 55, 55A Light guide member 55x Base end surface 55y Tip end surface 56 Rubber ring

Claims (6)

[Claims] 1. A first optical fiber bundle which passes through a light guide cord to be connected to a light source and whose output end is held in a state of a circular cross section by a first holding cylinder; An adapter for connecting the second optical fiber bundle whose section is held in a circular cross section by the second holding cylinder, both ends of which are connected to the first holding cylinder and the second holding cylinder; And a light guide member provided in the adapter body, disposed between the ends of the first and second optical fiber bundles, and coaxial with the ends. The light guide member has a tapered shape in which the cross section is circular and the diameter decreases from the proximal end to the distal end, and the proximal end surface of the light guide member emits the first optical fiber bundle. The illumination light transmission in an endoscope apparatus characterized in that the end surface is substantially in contact with the surface of the second optical fiber bundle and has a smaller diameter than the incident end surface of the second optical fiber bundle. System adapter. 2. The adapter main body is rotatable with respect to one of the second holding cylinder and the support cylinder, the support cylinder being connected to the first holding cylinder and housing and supporting the light guide member. And an adjusting cylinder connected immovably in the axial direction and connected to the other by screwing, the tip end face of the light guide member and the incident end face of the second optical fiber bundle being associated with the rotation of the adjusting cylinder. The illumination light transmission system adapter in the endoscope apparatus according to claim 1, wherein a distance between the adapters is adjusted. 3. The adapter body further includes a mounting cylinder, the mounting cylinder is detachably connected to the second holding cylinder, and the adjusting cylinder is rotatable and axially movable with respect to the mounting cylinder. The connection of the adjusting cylinder and the second holding cylinder is obtained by being improperly connected, while the support cylinder is detachably connected to the first holding cylinder. An illumination light transmission system adapter in the endoscope apparatus according to claim 1. 4. A male screw portion is formed on the outer periphery of the support tube, and a female screw portion screwed to the male screw portion is formed on the inner periphery of the adjusting tube. A rubber ring is attached to one of the inner circumferences in the axial direction away from the threaded portion, and the other has an annular abutment surface with which the rubber ring abuts in an elastically deformed state. The illumination light transmission system adapter in the endoscope apparatus according to claim 2 or 3, wherein 5. The illumination light transmission system adapter according to claim 1, wherein both ends of the adapter body are detachably connected to the first and second holding cylinders. . 6. The adapter body has a support tube connected to the first holding tube and housing and supporting the light guide member, and a mounting tube detachably connected to the second holding tube. The illumination light transmission system adapter in the endoscope apparatus according to claim 1, wherein the support tube and the mounting tube are detachably connected by screwing.