JP2002065587A - Optical endoscope - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an optical endoscope preventing the incidence of harmful light into an image fiber with simple constitution. SOLUTION: In this optical endoscope with the observation image transmitting image fiber and an illumination light transmitting light guide fiber disposed in an insertion part formed of a flexible tube inserted in an observation object, at least one of the image fiber and light guide fiber in the insertion part is covered with a dark colored coating material to prevent the incidence of the illumination light into the image fiber from the light guide fiber by the dark colored coating material.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical endoscope having an image fiber for transmitting an observation image and a light guide fiber for transmitting illumination light in an insertion portion.

[0002]

2. Description of the Related Art An image fiber for transmitting an observation image and a light guide fiber for transmitting illumination light are arranged close to each other in a flexible tube constituting an insertion portion of an optical endoscope (fiberscope). ing. Therefore, when the flexible insertion portion is deformed or the insertion portion is intentionally bent, the illumination light leaks from the light guide fiber in the deformed portion or the curved portion and enters the image fiber. So-called crosstalk may occur. It is necessary to prevent illumination light from entering the image fiber, since this causes a reduction in the contrast of the observed image.

A lubricant (lubricant) is provided to protect the optical fiber fibers constituting the image fiber and the light guide fiber from friction and pressure generated when the insertion portion is deformed or bent. When a white lubricant is used as the lubricant, a sufficient light-blocking property cannot be obtained depending on the lubricant, so that the leakage of the illumination light from the light guide fiber and the incidence of the illumination light to the image fiber as described above may occur. More likely to occur.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to provide an optical endoscope having a simple structure for preventing harmful light from entering an image fiber.

[0005]

SUMMARY OF THE INVENTION The present invention relates to an optical endoscope in which an image fiber for transmitting an observation image and a light guide fiber for transmitting illumination light are provided in an insertion portion formed of a flexible tube inserted into an observation object. At least one of the image fiber and the light guide fiber in the insertion portion is covered with a dark coating material having a light shielding property, and the dark coating material prevents illumination light from entering the image fiber from the light guide fiber. . According to this optical endoscope, it is possible to prevent harmful illumination light from entering the image fiber with a simple configuration in which the image fiber and the light guide fiber are covered with a dark coating.

When the insertion portion has a bending portion that can be bent from the outside, light leakage from the light guide fiber and incidence of harmful light to the image fiber tend to occur in the bending portion. Therefore, it is desirable that the dark coating material be configured to cover at least one of the image fiber and the light guide fiber at least in a range corresponding to the curved portion.

[0007] The dark coating material can be a coating tube made of silicon, polyamide-based polymer, fluororesin or the like. Alternatively, it is also possible to apply an adhesive to at least one of the outer surfaces of the image fiber and the light guide fiber, and configure the dark coating material with the adhesive.

[0008]

FIG. 1 shows an embodiment of the present invention. The optical endoscope 10 shown in FIG. 1 includes a flexible tubular insertion portion 11 and an operation portion 1 connected to the insertion portion 11.
Two. The insertion section 11 is a section to be inserted into an observation target such as a body cavity, and the operation section 12 is a section to be gripped by an operator of the endoscope. An eyepiece 13 is provided at the rear of the operation unit 12.
Is provided, and a light guide connection pipe 14 is extended from the operation unit 12 to the side.

The insertion portion 11 has a curved portion 15 near the distal end. A bending node ring 22 described later is provided in the bending section 15, and a bending operation wire is stretched between the bending node ring 22 and a bending operation member provided on the operation section 12. The bending operation member is configured by, for example, a knob that can be turned. The bending operation wire is pulled or loosened in accordance with the turning operation of the knob, and the bending portion 15 is bent. FIG. 1 does not show a bending operation member or a bending operation knob.

As shown in FIG. 2, a distal end body 20 is provided at the distal end of the insertion section 11, and a coating rubber constituting the appearance of the insertion section 11 including a curved portion 15 is provided on the outer peripheral surface of the distal end body 20. 21 is fixed with a thread. Tip body 2
A bending node 22 for bending the bending portion 15 is provided inside the inside of the bending section 15.
A metal mesh tube 23 is disposed between the two. Although not shown, the bending operation wire described above is connected to the bending node ring 22.

An objective optical system 25 for observation and a light distribution lens 26 are provided at the distal end of the distal end body 20. The objective optical system 25 includes a first lens group 25a and a second lens group 2 in an objective lens frame 27 fixed to the distal end body 20 from the object side.
5b and the third lens group 25c in this order.
An aperture 25d is provided between the lens group 25a and the second lens group 25b.
Is provided. The light incident end face of the image fiber 30 faces the rear part of the objective optical system 25. The image fiber 30 has a predetermined length from the light incident end face,
0, and extends from the insertion portion to the eyepiece section 13 through the insertion section 11 and the operation section 12, and the light emitting end face faces the eyepiece optical system 31. With the above configuration, the image of the observation target formed by the objective optical system 25 is sent to the eyepiece optical system 31 via the image fiber 30, and can be observed through the eyepiece optical system 31.

On the other hand, the light exit end face of the light guide fiber 32 is located behind the light distribution lens 26. A predetermined length of the light guide fiber 32 is inserted into the distal end body 20 from the light emitting end face.
The connector portion 33 is extended. Connector part 33
When attached to an external light source (not shown), illumination light enters the light guide fiber 32 in the connector 33 from the external light source, and is directed from the distal end portion of the insertion portion 11 to the observation target through the light guide fiber 32 and the light distribution lens 26. Illumination light.

Each of the image fiber 30 and the light guide fiber 32 is formed as a fiber bundle in which optical fiber fibers are bundled. Between the respective optical fiber fibers and on the outer surface of the fiber bundle, frictional and bending pressures are reduced. Lubricant is provided. Each of the lubricants is made of white powder such as boron nitride powder, polytetrafluoroethylene powder, fluorine-based oil, and fluorine-based grease. These substances are preferred as lubricants because they do not produce harmful substances when sterilized with hydrogen peroxide gas.

Further, the outer surfaces of the image fiber 30 and the light guide fiber 32 are covered with a white coated tube 37 and a black coated tube (dark coating material) 38 made of silicon, respectively, and each is put together as a fiber bundle. Among them, the white coated tube 37 covering the image fiber 30 is formed of white silicon, and the black coated tube 38 covering the light guide fiber 32 is formed of black colored silicon. The present embodiment is characterized in that a tube covering the light guide fiber 32 is provided as a black-coated tube 38 to provide light shielding properties.
In other words, by making the coating tube 38 dark, light-shielding properties can be obtained, and leakage of illumination light from the middle position of the light guide fiber 32 to the outside can be prevented. as a result,
Light for illumination does not enter the image fiber 30 in the insertion section 11, and a good observation image is obtained. In particular,
Since the light guide fiber 32 is also covered with the black coating tube 38 in the region inside the curved portion 15, the curved portion 1
Even if the bending operation of 5 causes the light guide fiber 32 to easily leak light, the black coating tube 38 can prevent the light leakage. In FIG. 1 and FIG. 2, a black-coated tube 3 is shown for easy identification of members.
8 is hatched, and other members are not hatched to indicate a cross section.

In the first embodiment, the coating tube covering the light guide fiber 32 is made to have a light-shielding property. However, a dark color (black) is used instead of the white coating tube 37.
By covering the image fiber 30 with the coated tube, it is possible to prevent harmful illumination light from entering the image fiber 30. That is, if at least one of the coating tubes of the image fiber 30 and the light guide fiber 32 is made to have a light-shielding dark color, it is possible to prevent illumination light from entering the image fiber 30 and obtain a good observation image. Of course, both the image fiber 30 and the light guide fiber 32 may be covered with a dark coating tube.

The material of the coated tube having the light-shielding property may be other than silicon. For example, the coated tube may be formed using a black fluororesin or a dark brown polyamide-based polymer. In order to make the coated tube black or dark brown with these materials, the tube may be colored after molding or the material may be mixed with color at the time of tube molding.

FIG. 3 shows a second embodiment of the present invention. In the figure, the same members as those in the first embodiment are denoted by the same reference numerals. In the second embodiment, a black silicone adhesive is thinly applied to the outer surface of a region from the distal end to the curved portion 15 of the light guide fiber 32, and the adhesive forms a dark coating 40 having a light shielding property. ing. At locations other than the dark coating 40, the light guide fiber 3
2 is entirely covered with a white coating tube 41, and the dark coating 40 is applied from above the white coating tube 41. The leakage of light and the incidence of external harmful light in the fiber bundle mainly occur at the curved portion. Even if such a dark coating 40 is formed only on the portion of the light guide fiber 32 corresponding to the curved portion 15, the image fiber 30
Harmful light can be effectively prevented from entering.

In the second embodiment, the dark coating 40 is provided on the light guide fiber 32 side.
Similarly to the embodiment, the adhesive may be applied to the image fiber 30 side to provide the dark film 40, or the dark film 40 may be provided to both the image fiber 30 and the light guide fiber 32.

The present invention is not limited to the above embodiment. For example, when a dark coating for shielding light is provided only on a portion corresponding to the curved portion 15 instead of the entire fiber bundle as in the second embodiment, it is easy and preferable to apply an adhesive or the like. It is also possible to form a partially dark film by using the coated tube as in the first embodiment instead of the agent. Conversely, when a dark coating is formed over the entire length of the fiber bundle, it is easy and preferable to form a colored tube for covering the entire fiber bundle as in the first embodiment. It is also possible to provide a dark coating by applying an adhesive as in the above embodiment over the entire length of the fiber bundle.

[0020]

As described above, according to the optical endoscope of the present invention, at least one of the image fiber and the light guide fiber in the insertion section is transmitted through the light guide fiber with a simple structure. It is possible to prevent the illuminated light from entering the image fiber and adversely affecting the observed image.

[Brief description of the drawings]

FIG. 1 is a diagram showing a first embodiment of an optical endoscope according to the present invention.

FIG. 2 is an enlarged sectional view showing the vicinity of the distal end of an insertion portion of the optical endoscope in FIG. 1;

FIG. 3 is a diagram showing a second embodiment of the optical endoscope according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Optical endoscope 11 Insertion part 12 Operation part 13 Eyepiece part 14 Light guide connection pipe 15 Curved part 20 Tip part main body 21 Coating rubber 22 Curved nodal ring 25 Objective optical system 26 Light distribution lens 30 Image fiber 31 Eyepiece optical system 32 Light guide fiber 33 Connector 37 White-coated tube 38 Black-coated tube (dark coating material) 40 Dark-coated film (dark coating material)

 ──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Hiroshi Sano 2-36-9 Maenocho, Itabashi-ku, Tokyo Inside Asahiko Gaku Kogyo Co., Ltd. (72) Inventor Ichiro Ninomiya 2-36-9 Maenocho, Itabashi-ku, Tokyo No. Asahi Gaku Kogyo Co., Ltd. F term (reference) 2H040 AA00 BA09 CA11 GA02 4C061 CC04 CC07 DD03 FF46 JJ03 JJ11

Claims (6)

[Claims] 1. An optical endoscope in which an image fiber for transmitting an observation image and a light guide fiber for transmitting illumination light are disposed in an insertion portion formed of a flexible tube inserted into an observation target. An optical endoscope, wherein at least one of the image fiber and the light guide fiber is covered with a dark coating material having a light-shielding property, and the dark coating material prevents illumination light from entering the image fiber from the light guide fiber. 2. The optical endoscope according to claim 1, wherein the insertion portion has a curved portion that can be operated to be curved from the outside, and the dark-colored coating material has at least a range corresponding to the curved portion. An optical endoscope covering at least one of the fiber and the light guide fiber. 3. The optical endoscope according to claim 1, wherein said dark-colored coating material is a coated tube made of silicon. 4. The optical endoscope according to claim 1, wherein the dark coating material is a coated tube made of a polyamide polymer. 5. The optical endoscope according to claim 1, wherein said dark-colored coating material is a coated tube made of fluororesin. 6. An optical endoscope according to claim 1, wherein said dark-colored coating material is made of an adhesive applied to at least one outer surface of an image fiber and a light guide fiber.