JP2000093389A - Endoscope apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To inexpensively obtain an lighting optical system which has a better light distribution characteristic and is simple in structure. SOLUTION: In a lighting optical system, a disc-shaped opal glass 131 is arranged so as to closely contact a tip end face of an optical fiber bundle 14 while the surface thereof is flush with the tip end face 33 of a scope. A light beam emitted from the optical fiber bundle 14 is transmitted through a transparent glass layer of the opal glass 131 and enters an opal layer. The light beam incident into the opal layer is diffused by component microscopic particles to allow irradiation of illumination light with a better light distribution characteristic outside expanding to a wider angle side. Thus, the observation peripheral part of an endoscope also can be lighted with a sufficient brightness.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an endoscope used for medical and industrial purposes, and more particularly to an endoscope having an improved illumination optical system mounted on an endoscope scope.

[0002]

2. Description of the Related Art Conventionally, an electronic endoscope apparatus used for medical and industrial purposes has an observation optical system and an illumination optical system in a scope housing, and illuminates a subject with the illumination optical system. Image information of the illuminated subject is extracted as a video signal, and an endoscopic image of the subject is displayed on a monitor or the like. The illumination optical system converts light from a light source built into the main body into an LG (Li
ght Guide), and has an emission structure in which the light emitted from the LG emission end is irradiated to the subject through an illumination lens.

[0003]

In the above-described conventional illumination optical system, a projection lens system including a plano-concave lens for illumination and a plurality of lenses is used at an LG emission end.
In addition, in some cases, ground glass is used in combination with a plano-concave lens or the like. However, when a plano-concave lens or a ground glass is used, there is a problem that the light distribution is insufficient, and there is a possibility that the brightness around the endoscope observation is insufficient. In addition, when a projection lens system is used, it is possible to solve the problem of insufficient brightness around the endoscope observation. However, there is a problem that the photographing lens system is expensive and the cost of the apparatus increases.
In addition, it is necessary to mold each of the plurality of lenses with high precision, and furthermore, it is necessary to perform positioning to prevent an error between scope lenses. was there.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional problems, and an object thereof is to provide an endoscope apparatus having an illumination optical system which is inexpensive, structurally simple and has good light distribution characteristics. It is to provide.

[0005]

In order to achieve the above object, the present invention illuminates an object with light from a light source guided through a light guide via an illumination optical system, and outputs illumination reflected light to an objective optical system. In the endoscope apparatus provided with the endoscope for receiving the light and observing the object, the illumination optical system includes a diffusion element composed of a diffusion glass material and a transparent glass material.

According to the present invention, by illuminating light from a light guide toward a subject through a diffusion element made of a glass material for diffusion and a transparent glass material, the full width at half maximum of the light distribution is widened, and good illumination light distribution performance is achieved. Is obtained. Also, high-precision molding and positioning work are not required.

[0007]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a configuration diagram showing a first embodiment of the endoscope apparatus of the present invention. The endoscope device
An electronic endoscope scope 1 which is detachable from the apparatus main body 2 is inserted into a patient's body or the like, and illumination light is emitted toward an observation target portion, so that an image of the observation target portion can be observed.

The electronic endoscope 1 guides light emitted from the light source device 3 of the apparatus main body 2 to a tip end thereof by a light guide (for example, an optical fiber bundle) 14. The light guided by the light guide 14 is
The subject is illuminated via the illumination optical system 13. The illumination reflected light is incident on a solid-state imaging device 17 such as a CCD via an observation optical system 12 provided at the distal end of the electronic endoscope 1. The solid-state imaging device 17 photoelectrically converts incident light,
An electric signal is output to the signal processing device 4. Then, the signal processing device 4 performs predetermined signal processing on the electric signal, and displays an image of the subject on the monitor 5.

The electronic endoscope 1 includes a distal end portion 11.
The observation optical system 12 and the illumination optical system 13 are disposed at the distal end component 11. The observation optical system 12 includes lenses 121 and 122 for condensing light reflected from the subject, a crystal filter 15 for dividing the light into two luminous fluxes, and routes the light divided by the crystal filter 15 to the solid-state imaging device 17 side. Optical path changing prism to be changed and cover glass 20
And a solid-state image sensor 17 covered with a solid-state image sensor. The solid-state imaging device 17 has a cable 18 for transmitting the output signal.
Is connected. The illumination optical system 13 irradiates the light transmitted through the optical fiber bundle 14 to the subject via the opal glass 131.

FIG. 2 is a front view showing the front of the distal end component 11 shown in FIG. Two ends of the illumination optical system 13 are arranged on both sides of the end of the observation optical system 12, and a water supply nozzle 2 that jets water in close proximity to the opening of the observation optical system 12.
2 and an air supply nozzle 23 for ejecting air are arranged.
Further, a forceps port 21 through which forceps and the like enter and exit is arranged.

Next, the operation of this embodiment will be described. Light emitted from the light source device 3 travels through the optical fiber bundle 14 formed by bundling optical fibers, and is further diffused by the opal glass 131 to illuminate the subject. Light illuminated from the opal glass 131 and reflected light from the subject are condensed by the lenses 121 and 122 and introduced into the crystal filter 15. The crystal filter 15 separates the introduced light flux into two light fluxes, and the optical paths of these two light fluxes are converted by the optical path conversion prism 16 and are incident on the solid-state imaging device 17.

The solid-state imaging device 17 converts the incident light into a color electric signal, and then converts the electric signal into a cable 18.
And outputs the signal to the signal processing device 4. The signal processing device 4 performs various processes on the input electric signal to generate a color video signal, and outputs the color video signal to the monitor 5. The monitor 5 displays an endoscope image of the subject corresponding to the input color video signal in color.

FIG. 3 is a sectional view showing a detailed example of the illumination optical system 13 shown in FIG. A circular plate-shaped opal glass 131 composed of an opal layer 31 and a transparent glass layer 32 is disposed in close contact with the distal end surface of the optical fiber bundle 14,
The surface of the opal glass 131 is located on the same plane as the scope tip surface 33.

The light beam 100 emitted from the optical fiber bundle 14 passes through the transparent glass layer 32 of the opal glass 131 and enters the opal layer 31. The light beam incident on the opal layer 31 is diffused by the constituent fine particles, and the illumination light 101 having good light distribution characteristics diffused to the wide-angle side is irradiated to the outside.

FIG. 4 shows the light distribution angle with the optical axis of the illumination lens formed of the above-mentioned opal glass 131 being 0 degree on the horizontal axis and the intensity (relative value) at each light distribution angle on the vertical axis. It is a light distribution characteristic diagram. Assuming that the width of the light distribution angle giving a half value with respect to the maximum value is the full width at half maximum of the light distribution, as is clear from FIG. 4, the full width at half maximum of the light distribution of this example is about 100 degrees. It is a light distribution that is no problem to obtain.

FIG. 5 is a characteristic diagram showing the light distribution characteristics of the optical fiber bundle 14 alone. As can be seen from FIG. 5, the full width at half maximum of the light distribution is about 40 degrees, and the effect of the diffuse light distribution by the opal glass 131 can be understood by comparing the characteristics of FIGS.

According to the present embodiment, the illumination light 101 is radiated through the opal glass 131 disposed at the tip of the illumination optical system 13 to obtain the illumination light 101 which spreads over a wide area with a simple configuration. Insufficient brightness at the periphery of the endoscope observation can be eliminated. Moreover, since the opal glass 131 is inexpensive, the above effects can be obtained without increasing the cost of the apparatus.

Further, since the exit surface of the opal glass 13 is located on the same plane as the end face 33 of the scope, when the electronic endoscope 1 enters the human body, for example, the exit surface of the opal glass 131 is turned on. It is possible to reduce the probability of being broken by hitting something during intrusion, and to improve the durability of the device.

FIG. 6 is a sectional view showing an illumination optical system which is a main part of a second embodiment of the endoscope apparatus according to the present invention. However, portions corresponding to those in the first embodiment shown in FIG. 3 are denoted by the same reference numerals, and description thereof will be omitted as appropriate. Also in this example, an opal layer 31 and a transparent glass layer 32 are provided in close contact with the tip of the optical fiber bundle 14, and an emission end face is flat, and a cylindrical opal glass 131 is disposed as a whole. Is disposed so as to protrude outside the end face 33 of the scope tip. As a result, the light beam 10 incident from the optical fiber bundle 14
0 is illuminated from the side surface of the opal glass 131 to the outside and becomes illumination light 101.

FIG. 7 is a characteristic diagram showing the light distribution characteristics of the illumination lens formed of the opal glass 131 of this embodiment. However, the characteristics of the optical fiber bundle 14 and the size of the opal glass 131 are the same as those of the first embodiment shown in FIG.

In this embodiment, the opal glass 131 is used.
Is projected from the scope tip surface 33,
Due to the diffused light emitted from the side surface of the opal layer 31, the full width at half maximum of the light distribution becomes wider than that of the first embodiment, and the peak of the light distribution intensity is not only at the light distribution angle of 0 °, but also at 0 °. , ± 20
In the range of degrees, more favorable illumination light distribution can be obtained in the endoscope observation. Other effects are similar to those of the first embodiment.

FIG. 8 is a sectional view showing an illumination optical system which is a main part of a third embodiment of the endoscope apparatus according to the present invention. However, portions corresponding to those in the first embodiment shown in FIG. 3 are denoted by the same reference numerals, and description thereof will be omitted as appropriate. The arrangement of the opal glass 131 of this example is the same as that of the first embodiment shown in FIG.
The side face of the optical fiber bundle 14 of the transparent glass layer 32 adjacent to the end of No. 4 is processed and polished into a concave shape.

Thus, when the light beam 100 emitted from the optical fiber bundle 14 enters the transparent glass layer 32, it is diffused by refraction of the concave portion. The diffused light enters the opal layer 31 and is further diffused and
The light exits from the light source layer 31 and becomes illumination light 101.

FIG. 9 is a characteristic diagram showing a light distribution characteristic of the illumination lens formed of the opal glass 131 of this embodiment. However, the characteristics of the optical fiber bundle 14 and the size of the opal glass 131 are the same as those of the first embodiment shown in FIG.

In this embodiment, the opal glass 131 is used.
By forming a concave portion in the light incident portion of the transparent glass layer 32 constituting the first embodiment, the light diffusing performance of the light beam incident from the optical fiber bundle 14 in the opal glass 131 can be improved in the first and second embodiments. Illumination light 1
01 makes it possible to illuminate a wide area even more. Other effects are similar to those of the first embodiment.

FIG. 10 is a sectional view showing an illumination optical system which is a main part of a fourth embodiment of the endoscope apparatus according to the present invention.
However, portions corresponding to those in the first embodiment shown in FIG. 3 are denoted by the same reference numerals, and description thereof will be omitted as appropriate. Also in this example, an opal glass 131 is disposed in close contact with the tip of the optical fiber bundle 14, and the opal glass 13
The exit surface of the first opal layer 31 is disposed so as to protrude outside the end face 33 of the scope. In addition, unlike the second embodiment shown in FIG. 6, the emission surface side of the opal layer 31 is processed and polished on a convex surface.

As a result, the illumination light 101 emitted from the opal layer 31 has more components distributed to the wide-angle side than in the second embodiment due to the convex effect.

FIG. 11 is a view showing the light distribution characteristics of the illumination lens formed of the opal glass 131 of this embodiment. However, the characteristics of the optical fiber bundle 14 and the size of the opal glass 31 are the same as those of the first embodiment shown in FIG.

According to the present embodiment, the opal glass 1
Since the outgoing end of the opal layer 31 forming the base 31 is formed as a convex portion, the diffusing performance for the light beam 100 incident from the optical fiber bundle 14 is improved as compared with the first and second embodiments. As in the third embodiment, the full width at half maximum of the light distribution is further increased, and the illumination light 101 suitable for wide-field endoscope observation can be obtained. Other effects are similar to those of the first embodiment.

The characteristics of the optical fiber bundle 14 shown in the first to fourth embodiments are merely examples, and the NA value of each optical fiber constituting the optical fiber bundle 14 is large. By adopting the opal layer 31, the light distribution characteristics of the optical fiber bundle 14 alone are improved (the full width at half maximum of the light distribution is increased).
The light distribution characteristics of the illumination light 101 emitted from the first embodiment can be further improved than those shown in the first to fourth embodiments.

The opal glass may be formed by changing the combination of the opal layer and the transparent glass layer according to the first to fourth embodiments. For example, the optical fiber bundle 14 side of the transparent glass layer 32 of the opal glass 131 has a concave shape,
By making the emission surface side of the opal layer 31 convex,
The illumination optical system 13 having the features of the third and fourth embodiments can be configured, and the light distribution characteristics can be further improved.

Further, the opal layer 31 of the opal glass 131 is formed in a circular flat plate shape, and the optical fiber bundle 14 side of the transparent glass layer 32 is formed in a concave shape. Also projecting outward, the third embodiment and the third embodiment
The illumination optical system 13 having the features of the first embodiment can be configured, and the light distribution characteristics can be further improved.

In the first to fourth embodiments, the application of the opal glass to the illumination optical system of the electronic endoscope has been described. However, the invention may be applied to a fiber scope.

In the first to fourth embodiments, an example in which one opal glass is used as the illumination optical system has been described. However, a plurality of opal glasses may be used in an overlapping manner.

In the first to fourth embodiments, the opal glass is arranged so as to have the opal layer on the first surface (tip side) and the transparent glass layer on the second surface (opposite side). Opal glass having a transparent glass layer on one side and an opal layer on the second side may be arranged. However, in order to further reduce light loss, it is desirable to dispose opal glass as in the first to fourth embodiments.

Furthermore, in the first to fourth embodiments, opal glass is used as the diffusion element, but other materials may be used.

[0037]

As described above in detail, according to the endoscope apparatus of the present invention, it is possible to obtain an inexpensive, structurally simple and good light distribution characteristic, and to obtain the brightness around the endoscope observation. Shortage can be resolved.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing a first embodiment of an endoscope apparatus of the present invention.

FIG. 2 is a front view showing the front of the distal end component shown in FIG. 1;

FIG. 3 is a sectional view showing a detailed example of the illumination optical system shown in FIG. 1;

4 is a characteristic diagram showing light distribution characteristics of the illumination optical system shown in FIG.

FIG. 5 is a characteristic diagram showing light distribution characteristics of the optical fiber bundle shown in FIG. 3 alone.

FIG. 6 is a cross-sectional view showing an illumination optical system as a main part of a second embodiment of the endoscope apparatus according to the present invention.

7 is a characteristic diagram showing light distribution characteristics of the illumination optical system shown in FIG.

FIG. 8 is a sectional view showing an illumination optical system which is a main part of a third embodiment of the endoscope apparatus according to the present invention.

9 is a characteristic diagram showing light distribution characteristics of the illumination optical system shown in FIG.

FIG. 10 is a sectional view showing an illumination optical system which is a main part of a fourth embodiment of the endoscope apparatus according to the present invention.

FIG. 11 is a characteristic diagram showing light distribution characteristics of the illumination optical system shown in FIG.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 electronic endoscope scope 2 device main body 3 light source device 4 signal processing device 5 monitor 11 tip component 12 observation optical system 13 illumination optical system 14 optical fiber bundle 15 crystal filter 16 prism for optical path conversion 17 solid-state imaging device 18 cable 19 member Reference Signs List 20 cover glass 21 forceps port 22 water supply nozzle 23 air supply nozzle 31 opal layer 32 transparent glass layer 100 light beam 101 illumination light 121, 122 lens 131 opal glass

Claims (6)

[Claims] 1. An endoscope having an endoscope for illuminating a subject with light from a light source guided through a light guide via an illumination optical system, receiving illumination reflected light by an objective optical system, and observing the subject. In the endoscope apparatus, the illumination optical system includes a diffusion element including a diffusion glass material and a transparent glass material. 2. The endoscope apparatus according to claim 1, wherein the diffusion element is an opal glass including an opal layer and a transparent glass layer. 3. The endoscope apparatus according to claim 1, wherein the diffusion element is disposed closely or in close proximity to an emission end face of the light guide. 4. A light emitting surface of the diffusion element is formed in a flat plate shape or a convex shape, and a part thereof is substantially flush with a distal end surface of the endoscope or protrudes outward from the distal end surface. The endoscope apparatus according to any one of claims 1 to 3, wherein the endoscope apparatus is provided so as to be provided. 5. The endoscope apparatus according to claim 1, wherein the light incident surface of the diffusion element is formed in a concave shape. 6. The diffusing element according to claim 2, wherein the transparent glass layer is formed on a light incident surface and the opal layer is formed on a light emitting surface. 2. The endoscope device according to claim 1.