JPH10286235A - Endoscope device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the diameter of the body insertion part of an endoscope, in an endoscope device. SOLUTION: As the light source of a light source device 3, an He-Cd laser 20 being three primary color laser beams and an He-Ne laser 21 being red laser beams are used. The respective laser beams LW, LR oscillated from the respective lasers 20, 21 are passed through ND filters 22, 23, respectively, to attenuate them to a prescribed intensity, and then they are converged to a beam splitter 26 by means of lenses 24, 25. Both laser beams LW and LR are synthesized by the beam splitter 26, and the synthesized laser beam is emitted from the light source device 3 as an outgoing beam Li, and it is incident on a light guide 10 consisting of small-diameter single optical fibers.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an endoscope apparatus, and more particularly to an endoscope apparatus in which a light source device for illumination is improved.

[0002]

2. Description of the Related Art Conventionally, an endoscope apparatus has been widely used for observing the inside of a living body or treating while observing the inside of a living body. When observing the inside of a living body using an endoscope, light emitted from an illumination light source arranged outside the living body is generated through a light guide made of an optical fiber housed in a flexible introduction tube. It is common to illuminate the observation part by guiding it into the body.

In a conventional endoscope apparatus, ordinary illumination is realized using a lamp light source (white light) and an optical fiber bundle. However, since the lamp light cannot be sufficiently stopped down, an optical fiber bundle (light) is used. There is a problem that the diameter of the guide) becomes large, and as a result, the body insertion portion itself of the endoscope becomes thick.

Further, a tumor-affinity fluorescent substance which emits fluorescence when excited by light is absorbed in advance in a tumor part of a living body, and the part is irradiated with excitation light of the fluorescent substance to generate fluorescence. And a fluorescent image diagnostic apparatus (for example, Japanese Examined Patent Publication No.
-9464, JP-A-1-136630, JP-A-7-59783, etc.) are also widely used. In such an endoscope apparatus, an optical fiber for guiding white light is added to an optical fiber for guiding excitation light so that a normal image (an image obtained by white light illumination) and a fluorescent image can be switched and observed. In the case where the endoscope is provided (Japanese Patent Publication No. 3-58729), there is a problem that the diameter of the endoscope is further increased.

[0005]

Since the endoscope is inserted into a human body, the thickness of the guide portion directly burdens the subject. Therefore, it is desirable that the diameter of the body insertion portion of the endoscope be as small as possible.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an endoscope apparatus capable of making a body insertion portion thin.

[0007]

An endoscope apparatus according to the present invention comprises:
In an endoscope apparatus for guiding light from a light source device by a light guide to irradiate a subject and observing the subject image, the light source device emits white laser light including a plurality of oscillation wavelengths. It is characterized by having.

The light source device is provided with a laser which oscillates three wavelengths simultaneously, that is, oscillates white laser light including three wavelengths, such as a He-Cd laser which is a three primary color (white) laser, for example. Alternatively, a plurality of laser lights oscillated from a plurality of lasers may be combined into white laser light.

Further, it is preferable that the light source device includes an intensity adjusting means for adjusting the light intensity of the laser light oscillated from the laser.

The intensity adjusting means may be, for example, an ND filter arranged on the optical path of the laser light for adjusting the intensity of the laser light, or may be a means for adjusting the output of the laser itself. In a light source device including a plurality of lasers, it is desirable that the laser light oscillated from each laser be adjusted in intensity and then combined to form white laser light.

In order to improve the color reproduction of a reddish living tissue, it is desirable that the white laser light emitted from the light source device has two or more red oscillation wavelengths. This may be achieved, for example, by configuring the light source device alone with a white laser that oscillates white laser light and a laser that oscillates laser light of a red wavelength different from the red wavelength included in the white laser light. Alternatively, it may be achieved by using a green laser, a blue laser that is a laser having a single oscillation wavelength, and two types of red lasers having different oscillation wavelengths.

It is preferable that the endoscope apparatus further includes a light diffusing means disposed at an emission end of the light guide, and that the white laser light transmitted through the light diffusing means is provided. It is desirable to further include an illuminance distribution adjusting unit that adjusts the illuminance distribution to the subject.

[0013]

According to the endoscope apparatus of the present invention, since a laser beam having good convergence is used as illumination light, a single optical fiber can be used as a light guide. In comparison, the diameter of the body insertion portion of the endoscope can be reduced, and the burden on the subject during the examination can be reduced.

[0014]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows an electronic endoscope apparatus according to the present invention. The present endoscope apparatus 1 includes an endoscope main body 2, a light source device 3 for supplying illumination light or excitation light to the endoscope main body 2, and a distal end portion of the endoscope main body 2 inserted into a living body 4. And a monitor 6 for displaying an image based on the image signal output from the video signal circuit 5.

A light guide 10 for transmitting illumination light (emitted light) Li for irradiating an observation site of the living body 4 is provided inside the endoscope body 2, and is disposed close to a tip end of the light guide 10.
A diffusing plate 11 for diffusing the emitted light Li to uniformly irradiate the living body 4 with the emitted light Li, an illuminance distribution adjusting filter 12 for adjusting the illuminance distribution of the emitted light Li in the living body 4, and an observation light from the living body 4 ( Imaging optical system 1 for imaging Lr
3, and a solid-state imaging device 14 such as a CCD on which the observation light Lr is formed.

The light source device 3 has 441.6 nm, 537.8 nm, 636.0 n
He-Cd laser 20, which is a laser of three primary colors (white) that simultaneously oscillates three wavelengths of m, He-Ne laser 21 that oscillates laser light of a red wavelength of 632.8 nm, and lasers 20, 21 ND filters 22, 23 for adjusting the intensity of each laser light LW, LR, lenses 24, 25, and a beam splitter 26. The laser beams LW and LR are converged on the beam splitter 26 by the lenses 24 and 25, are combined by the beam splitter 26, are emitted as white laser light from the light source device 3, and enter the light guide 10.
That is, the white laser light LW is emitted from the He-Cd laser 20, and the red laser light LR emitted from the He-Ne laser 21 is combined with the white laser light LW to form a white laser light including two red wavelengths. The laser light is emitted from the light source device 3 as emission light Li. In the light source device 3, He
Although it is possible to use only the Cd laser 20 and use white laser light emitted from the He-Cd laser 20 for emission as observation light, redness can be obtained by using laser light containing two or more red wavelengths as emission light. It is possible to improve the color reproducibility of a biological dye having a color. In the present embodiment, white laser light including two red wavelengths is used as the emitted light, but laser light having a plurality of red wavelengths may be combined.

In the present embodiment, a single small-diameter optical fiber is used as the light guide 10. Since laser light is used as a light source, light can be guided by a single small-diameter optical fiber, and as a result, the diameter of the endoscope body inserted into the living body can be reduced.

When the light emitted from the light guide 10 is used as illumination as it is, the illuminance distribution of the illuminating light is not uniform due to the characteristics of the light guide 10, and the central portion of the subject is bright and the peripheral portion is dark. Further, the imaging optical system also has a characteristic that the center of the subject is bright and the periphery is dark, and it is difficult to obtain a captured image that is easy to observe. The illuminance distribution adjustment filter 12 is for solving such a problem, and for example, an ND filter in which the light transmittance of the central portion is lower than the light transmittance of the peripheral portion can be used. .

Hereinafter, the operation of the electronic endoscope apparatus 1 when observing an image will be described.

In the light source device 3, the He-Cd laser 20 and
Laser light LW oscillated from the He-Ne laser 21,
The LR is transmitted through the ND filters 22 and 23 and attenuated to a predetermined intensity, and is converged on the beam splitter 26 by the lenses 24 and 25. In the beam splitter 26, the two laser lights LW and LR are multiplexed and emitted from the light source device 3 as emission light Li which is a white laser light, and is incident on the light guide 10. The emitted light Li guided by the light guide 10 is diffused by a diffusion plate 11 arranged at the tip of the light guide 10, further emitted through an illuminance distribution adjusting filter 12, and irradiated to the living body 4.

The reflected light Lr from the living body 4 is received by the imaging optical system 13 and is imaged on the solid-state imaging device 14. The video signal from the solid-state imaging device 14 is processed by the video signal circuit 5 and then input to the monitor 6, and an observation image based on the video signal is displayed on the monitor 6 for observation.

Next, an electronic endoscope apparatus according to a second embodiment of the present invention will be described. Only differences from the electronic endoscope apparatus according to the first embodiment will be described,
Common components are denoted by the same reference numerals.

In the present embodiment, the light source device 3 is 630n
m, a semiconductor laser (LD) 31 that oscillates a laser beam LR with a red wavelength, a second harmonic generation element (SHG) 32 that oscillates a laser beam LG with a green wavelength of 534 nm, and a laser beam LB with a blue wavelength of 473 nm Second harmonic generation element (S
HG) 33 light sources, ND filters 34, 35, 36 arranged on the optical paths of the respective laser beams LR, LG, LB to adjust the laser beam intensity, and a dichroic for multiplexing the laser beams LR, LG, LB. Mirrors 37 and 38 are provided.

The dichroic mirror 37 transmits light in the red wavelength range and reflects light of a shorter wavelength.
The red laser light LR emitted from the LD 31 is transmitted and S
The green laser light LG emitted from the HG 32 is reflected.
By this action, the red laser light LR and the green laser light LG
Are multiplexed. The dichroic mirror 38 reflects blue wavelength light and transmits longer wavelength light, transmits the red and green laser lights LR and LG transmitted through the dichroic mirror 37, and is emitted from the SHG 33. The blue laser beam LB is reflected. By this action, the laser beams LR, LG, and LB are combined and become white laser light, which is emitted from the light source device 3 as emission light Li.

In the above embodiment, the light intensity of the laser light oscillated from the laser is adjusted by the ND filter arranged on the laser beam path.
It can also be performed by controlling the drive current of D (LD for generating a fundamental wave in SHG) or the drive current of the excitation LD of the light source LD.

As described above, in the endoscope apparatus of the present invention, since a laser beam having good convergence is used as the light emitted from the light source apparatus, a single small-diameter optical fiber is used as the light guide. Can be. Therefore, the diameter of the endoscope main body can be reduced, and the burden on the subject during in vivo observation can be reduced.

When the endoscope apparatus according to the present invention is used as an endoscope apparatus having a built-in fluorescence diagnostic apparatus, the light source apparatus 3 sets the endoscope apparatus to a wavelength in the wavelength range of white laser light (normal illumination light) or excitation light. It is sufficient that the limited laser light is selectively switched so that the laser light can be emitted as emission light, and the light guide used for guiding the illumination light can be commonly used for guiding the excitation light. Therefore, the diameter of the endoscope main body can be reduced even in an endoscope apparatus having a built-in fluorescence diagnostic apparatus. Further, in such an endoscope apparatus, since the exit ends of the excitation light and the normal illumination light coincide with each other, a fluorescent image and a normal image without parallax can be obtained.

[Brief description of the drawings]

FIG. 1 is a schematic diagram of an electronic endoscope apparatus according to a first embodiment of the present invention.

FIG. 2 is a schematic diagram of an electronic endoscope apparatus according to a second embodiment of the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 electronic endoscope device 2 endoscope main body 3 light source device 4 living body 5 video signal circuit 6 monitor 10 light guide 11 diffusion plate 12 illuminance distribution adjustment filter 13 imaging optical system 14 solid-state imaging device 20 He-Cd laser 21 He-Ne Laser 22, 23 ND filter 24, 25 Lens 26 Beam splitter

Claims (8)

[Claims] 1. An endoscope apparatus for guiding light from a light source device through a light guide to irradiate a subject and observing the subject image, wherein the light source device includes a white laser beam including a plurality of oscillation wavelengths. An endoscope apparatus that emits light. 2. The endoscope apparatus according to claim 1, wherein the white laser light includes at least two different red wavelengths. 3. The endoscope apparatus according to claim 1, wherein the light source device includes a single white laser that oscillates white laser light. 4. The laser device according to claim 1, wherein the light source device includes a plurality of lasers, and multiplexes respective laser lights oscillated from the plurality of lasers and emits the combined laser light as the white laser light. An endoscope device according to any one of claims 1 to 3. 5. The light source device according to claim 1, further comprising an intensity adjusting unit for adjusting the light intensity of each laser light before combining the laser lights emitted from the plurality of lasers. Item 5. The endoscope device according to Item 4. 6. The endoscope apparatus according to claim 1, wherein a light diffusing unit is provided at an emission end of the light guide. 7. The endoscope apparatus according to claim 6, further comprising an illuminance distribution adjusting unit that adjusts an illuminance distribution of the white laser light transmitted through the light diffusion unit to the subject. . 8. The endoscope apparatus according to claim 1, wherein said light guide is made of a single optical fiber.