JP3231417B2 - Endoscope - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an endoscope in which an observation optical system and a light guide fiber bundle are inserted into one lumen inside an insertion portion.

[0002]

2. Description of the Related Art In one lumen, an observation optical system in which an image guide fiber is joined to an objective lens rod formed by combining rods, and a flexible tube in which a ride guide fiber is inserted and disposed are provided. An endoscope is disclosed, for example, in Japanese Utility Model Laid-Open No. 62-84012.

This endoscope is configured as shown in FIG. That is, the resin flexible tube 2 is fitted on the outer periphery of the light guide fiber bundle 1. A metal foil 3 is interposed between the outer periphery of the distal end of the light guide fiber bundle 1 and the inner surface of the distal end of the flexible tube 2.

A plurality of rod-shaped objective lenses 4 are provided on the axis of the light guide fiber bundle 1. A tubular lens frame 5 is fitted on the outer periphery of the objective lens 4 as a light shielding member, the light guide fiber bundle 1 and the objective lens 4 are separated from each other, and light from the light guide fiber bundle 1 is incident on the objective lens 4. It is not configured.

[0005] An image guide fiber bundle 6 is connected to the base end of the objective lens 4, and a cover glass 7 is attached to the front end thereof. The cover glass 7 is provided so as not to protrude from the distal end of the flexible tube 1.

[0006] An endoscope in which the diameter of a flexible tube is reduced is disclosed in Japanese Utility Model Laid-Open Publication No. 64-19912. This endoscope is configured as shown in FIGS. 7A and 7B. That is, the resin flexible tube 11 is fitted on the outer periphery of the light guide fiber bundle 10. An image guide fiber bundle 12 is inserted on the axis of the light guide fiber bundle 10. An objective lens rod 13 composed of a plurality of objective lenses is provided at the tip of the image guide fiber bundle 12.

The objective lens rod 13 has a cover glass 14 provided on the distal end side thereof and a cover glass 1
4, a first objective lens 15 provided in close contact with the rear surface
A second objective lens 16 spaced apart from the first objective lens 15 and in close contact with the distal end surface of the image guide fiber 11, and first and second objective lenses 15, 16;
And a transparent filler 17 filled between the two.

A cylindrical reinforcing member 18 is fitted on the outer periphery of the light guide fiber bundle 10.
The outer peripheral surface of the objective lens rod 13 is coated with a light-impermeable adhesive 19, and light transmitted through the light guide fiber bundle 10 is directly incident from the side of the objective lens rod 13 to form an observation image. This prevents flare phenomena such as a decrease in contrast.

[0009]

However, in the endoscope described above, the objective lens rod 13 is formed by integrating the objective lens into a rod shape in order to reduce the diameter of the flexible tube. The frame 5 is eliminated, and the diameter is reduced by the thickness. Further, by applying a light-impermeable adhesive to the outer periphery of the objective lens rod 13, light transmitted through the light guide fiber bundle 10 is prevented from directly entering from the side of the objective lens rod 13. However, in the step of applying a light-impermeable adhesive to the objective lens rod 13, unevenness occurs, and the light guide fiber bundle 1
There was a problem that the light of 0 could not be shielded sufficiently and the flare phenomenon could not be prevented.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an endoscope in which a flare phenomenon is reliably prevented and a flexible tube is reduced in diameter. is there.

[0011]

In order to achieve the above object, an endoscope according to the present invention has an image guide fiber in a rod-shaped objective lens in one lumen inside an insertion portion of the endoscope. A light-shielding member formed by inserting the observation optical system and the light guide fiber joined together and cutting a part of the circumference of the hollow cylindrical member along the entire length in the axial direction of the insertion portion into the lumen. And a notch of the light-shielding member is joined to an inner peripheral surface of the lumen, and the objective lens is fixed inside the lumen, and the lumen is formed so that the light-shielding member serves as a partition wall between the objective lens and the light guide fiber. It is located within.

[0012]

According to the endoscope constructed as described above, a light-shielding member in which a part of the circumference of the hollow cylindrical member is cut out along the entire length in the axial direction of the insertion portion is fitted on the outer periphery of the objective lens rod. As a result, the light shielding member functions as a partition separating the light guide fiber and the objective lens rod, preventing light transmitted into the light guide fiber from directly entering the objective lens rod and preventing the flare phenomenon. can do.

[0013] Further, since both edges of the cutout portion of the light shielding member are fixed so as to be in contact with the inner peripheral surface of the lumen, the diameter of the insertion portion is reduced by the thickness of the light shielding member. The diameter can be increased.

[0014]

1 and 2 show a first embodiment of the present invention.
It will be described based on. FIG. 2 shows the entire endoscope.
An eyepiece 21 is provided at the rear end of the operation unit 20 of the endoscope. A universal cord 22 is connected to a side of the operation unit 20. This universal code 2
A light guide connector 23 is provided at the distal end of the second unit 2 so that it can be detachably connected to a light source device (not shown).
The insertion section 24 includes a flexible tube section 25 and a tip section 26.

The insertion portion 24 is provided with one lumen 24a as shown in FIG. This lumen 24
A light guide fiber bundle 27 is provided inside a. The outer periphery of the light guide fiber bundle 27 is covered by the flexible tube 25.

A reinforcing member 28 is provided between the outer periphery of the distal end of the light guide fiber bundle 27 and the inner surface of the distal end of the flexible tube 25.

At the tip of the light guide fiber bundle 27, a light-shielding member 30 is formed by cutting out a part of the circumference of a hollow cylindrical member made of metal or resin over the entire length in the axial direction of the insertion portion 24. Is provided. The notch 31 of the light shielding member 30 is provided so as to contact the inner peripheral surface of the reinforcing member 28.

An objective lens rod 34, which is formed by bonding a bend rate distribution type lens 32 and a cover glass 33 to be integrated, is adhered and fixed to the inner peripheral surface on the distal end side of the light shielding member 30. An image guide fiber bundle 35 is joined to the rear end of the objective lens rod 34 to form an observation optical system.

The edge 36 of the notch 31 of the light shielding member 30 is in contact with the inner peripheral surface of the reinforcing member 28. Therefore, the objective lens rod 34 and the light guide fiber bundle 27 are separated from each other by the reinforcing member 28 and the light shielding member 30, and the light shielding member 30 functions as a partition so that light transmitted into the light guide fiber bundle 27 directly The light is prevented from being incident on the lens rod 34.

A transparent adhesive 37 is applied to the front end of the light guide fiber bundle 27 and the insertion portion 24 is applied to the rear end.
The light guide connector 23 is guided to the operation unit 20 through the inside and further reaches the distal end of the light guide connector 23 through the inside of the universal cord 22. On the other hand, the rear end side of the image guide fiber bundle 35 is guided to the operation section 20 through the inside of the insertion section 24 and reaches the eyepiece section 21.

Therefore, when the light guide connector 23 is connected to the light source device, the light from the light source device is emitted from the distal end of the insertion portion 24 through the light guide fiber bundle 27, and is radiated to the illuminated object. Light reflected from the body passes through the objective lens rod 34 and forms an image on the distal end surface of the image guide fiber bundle 35, and the image is transmitted to the eyepiece 21 by the image guide fiber bundle 35, and is received through the eyepiece 21. The irradiation body can be observed.

According to the endoscope of the first embodiment thus constructed, the edge 36 of the notch 31 of the light shielding member 30 abuts on the inner peripheral surface of the reinforcing member 28, and the reinforcing member 28 and the light shielding member 3
0, the objective lens rod 34 and the light guide fiber bundle 27 are separated from each other.
0 functions as a partition, and the light guide fiber bundle 27
Can be prevented from directly entering the objective lens rod 34, and the flare phenomenon can be prevented.

Further, since both edges of the notch 31 of the light shielding member 30 are fixed so as to be in contact with the inner peripheral surface of the reinforcing member 28, the diameter of the insertion portion 24 is increased by the thickness of the light shielding member 30. Therefore, the diameter of the insertion portion 24 can be reduced.

Next, a second embodiment of the present invention will be described with reference to FIG.
Description will be made based on (b). The same components as those in the first embodiment are denoted by the same reference numerals, and the description will not be repeated.
As shown in FIG. 3, a light guide fiber bundle 27 is provided inside the insertion section 24. A cylindrical member 40 is inserted into the light guide fiber bundle 27 along the axial direction. The cylindrical member 40 forms a channel 41 through which forceps and the like are inserted. The flexible tube portion 25 is directly fitted on the light guide fiber bundle 27.

An objective lens rod 42 is inserted through the light guide fiber bundle 27 along the axial direction of the insertion portion 24. The objective lens rod 42 is located closer to the outer peripheral surface from the center of the light guide fiber bundle 27. The light shielding member 4 is provided on the outer peripheral surface of the objective lens rod 42.
5 are fitted. The light blocking member 45 is
Is cut out over the entire length in the axial direction. The notch 46 of the light shielding member 45 is attached and fixed in a state of contacting the inner peripheral surface of the flexible tube 25. That is, the objective lens rod 42 is separated from the light guide fiber bundle 27 by the flexible tube 25 and the light shielding member 45.

The objective lens rod 42 is formed by joining a plurality of objective lenses 43 with a transparent filler 44 and attaching a cover glass 47 to the tip of the objective lens 43 on the tip side. An image guide fiber bundle 35 is connected to the base end side of the objective lens rod 42 to form an observation optical system.

The other structure is almost the same as that of the first embodiment.

In the second embodiment configured as described above, the same operation and effect as those of the first embodiment can be obtained.

Next, a third embodiment of the present invention will be described with reference to FIG.
This will be described with reference to FIG. 5B and FIG. The same components as those in the first embodiment are denoted by the same reference numerals, and the description will not be repeated. As shown in FIGS. 4A and 4B, the insertion portion 24 is formed of a flexible multi-lumen tube 50.
One lumen 51 of this multi-lumen tube 50
Is a channel through which forceps and the like are inserted. The multi-lumen tube 50 is provided with a lumen 52 having an insertion hole having a substantially crescent cross section. The light guide fiber bundle 27 is inserted through the lumen 52.

An objective lens rod 34 is provided at the center of the light guide fiber bundle 27 along the axial direction of the insertion section 24. An image guide fiber bundle 35 is connected to the base end side of the objective lens rod 34 to constitute an observation optical system.

Between the objective lens rod 34 and the light guide fiber bundle 27, a pair of light shielding members 53 are provided. The light shielding member 53 is formed to be curved along the outer peripheral surface of the objective lens rod 34, and is formed by cutting out the entire length in the axial direction of the insertion portion 24. That is, the ends of the light shielding member 53 are
And is provided in contact with the peripheral surface of the objective lens rod 34.

The side surface of the objective lens rod 34 in the radial direction is shielded from light by the inner peripheral surface of the lumen 52, and the other side surface is shielded from light by the light shielding member 53. Thus, the light guide fiber bundle 27 and the objective lens rod 34 are separated by the lumen 52 and the light shielding member 53.

A cover glass 54 is provided at the tip end of the light guide fiber bundle 27.

Next, the operation of the third embodiment will be described.
The objective lens rod 34 has a radial side surface with a lumen 52.
The light guide fiber bundle 27 and the objective lens rod 34 are separated from each other by being shielded from light by an inner peripheral surface of the light guide fiber bundle and shielded from light by a light shielding member 53 on a side surface other than the radial direction.

Since the light-shielding member 53 covers the outer periphery of the objective lens rod 34 except for the radial direction of the multi-lumen tube 50, the radial dimension of the insertion portion 24 is increased by the thickness of the light-shielding member 53. It will not be. Therefore, the insertion portion 2 is further improved than the first and second embodiments.
4 is achieved.

[0036]

Since the present invention is configured as described above,
The light-shielding member functions as a partition that separates the light guide fiber bundle from the objective lens rod, so that the flare phenomenon is reliably prevented, and both ends of the cutout of the light-shielding member are fixed so that they contact the inner peripheral surface of the lumen As a result, the diameter of the insertion portion is reduced by the thickness of the light shielding member, and the diameter of the insertion portion is reduced.

[Brief description of the drawings]

FIG. 1 shows an endoscope according to a first embodiment of the present invention;
(A) is sectional drawing which follows the AA line of (b), (b) is the longitudinal side view of the front-end | tip of an insertion part.

FIG. 2 is a side view of the endoscope of the embodiment.

FIG. 3 shows an endoscope according to a second embodiment of the present invention;
FIG. 3B is a cross-sectional view taken along line BB of FIG. 3B, and FIG.

FIG. 4 shows an endoscope according to a third embodiment of the present invention;
FIG. 3B is a cross-sectional view along the line CC of FIG. 3B, and FIG.

FIG. 5 is a sectional view taken along the line D-D in FIG. 4A in the embodiment.

FIG. 6 is a longitudinal sectional side view showing a distal end of an insertion portion of a conventional endoscope.

7A and 7B show an insertion portion of another conventional endoscope, in which FIG. 7A is a cross-sectional view taken along line EE of FIG. 7B, and FIG. 7B is a vertical side view of a distal end of the insertion portion.

[Explanation of symbols]

Reference numeral 24: insertion portion, 24a: lumen, 27: light guide fiber bundle, 30: light shielding member, 31: cutout portion, 34: objective lens rod, 35: image guide fiber bundle.

Claims (1)

(57) [Claims] 1. An endoscope in which a light guide fiber and an observation optical system in which an image guide fiber is joined to a rod-shaped objective lens is inserted into one lumen inside an insertion portion of the endoscope. A light-blocking member formed by cutting a part of the circumference of the cylindrical member over the entire length in the axial direction of the insertion portion is provided inside the lumen, and the cut-out portion of the light-blocking member is provided on the inner peripheral surface of the lumen. And an endoscope, wherein the objective lens is fixed inside the endoscope, and the light shielding member is disposed in the lumen so as to serve as a partition wall between the objective lens and the light guide fiber.