JP3096326B2 - Endoscope device - 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 apparatus in which illumination for an endoscope can correspond to the distance of a subject.

[0002]

2. Description of the Related Art When photographing an endoscope in a body cavity, a subject is illuminated by light from a light source device and photographed by a photographic film or a TV camera. The distance and the long distance are mixed, and the short distance portion is overexposed and flies white. Therefore, the subject information cannot be accurately recorded and stored. To solve this, underexposure was corrected to prevent overexposure. In the case of a TV camera, a similar measure has been taken by switching to peak metering.

[0003] Even if such a solution is taken, there is a drawback that a long distance portion is darkened and blackened due to a small latitude of a film or an image pickup device. It has been considered impossible to do so.

[0004]

The illumination in the conventional endoscope apparatus is distributed so that the illumination range is as constant as possible. However, the brightness is generally inversely proportional to the square of the distance, so that there is a difference in brightness between a portion at a short distance and a portion at a long distance. Therefore,
When a long distance and a short distance coexist, there is a drawback in that an overexposure or underexposure part occurs in capturing an endoscopic image.

The present invention has been made in view of the above circumstances, and illuminates a subject at both a distance and a near distance, which has been impossible in the prior art, to a certain level of brightness, and provides a method for illuminating white and black in a photograph. It is an object of the present invention to provide an endoscope apparatus that can eliminate halation in a TV image and the like.

[0006]

[MEANS FOR SOLVING THE PROBLEMS] To achieve the above object
Endoscopic device that by the present invention, the imaging means to imaging the subject
In the endoscope apparatus equipped with supplies irradiation bright light lamp
When, the illumination light received by the light incident end surface, wherein from the output end face
A light for irradiating a subject with a light beam corresponding to the incident end face
Guide and radially with respect to the axis of incidence of the light guide
It is arranged for each of a plurality of different optical path regions and intersects the incident axis.
A plurality of diaphragm blades can be movable in a direction, said plurality of light
The subject irradiated with the illumination light through the road area can be viewed through the endoscope.
A plurality corresponding to each of the plurality of optical path regions obtained by observation
Photometry of the observation area, and a plurality of lights for each of the plurality of observation areas.
A photometric means for outputting a light quantity signal;
Drive control for independently driving the plurality of aperture blades
Characterized by comprising a means.

[0007]

[Operation] In the above configuration, the illumination light from the lamp
Illuminate the light guide and illuminate through the plurality of light path areas
Obtained by endoscopic observation of a subject irradiated with light
Measuring a plurality of observation areas corresponding to each of the plurality of optical path areas.
Amount of light measured by light means and output for each of the plurality of observation areas
The plurality of aperture blades are controlled by the drive control means in response to a signal.
Each root is driven independently .

[0008]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 5 relate to an embodiment of the present invention.
FIG. 1 is an overall schematic configuration diagram of the present embodiment, FIG. 2 is an explanatory diagram showing a divided state of a photographing range, FIG. 3 is an explanatory diagram showing a divided state of a light receiving element in a camera, and FIG. Aperture blades,
FIG. 5 is an explanatory view showing a divided state of a light guide end face and FIG.
Is a graph showing the relationship between each area and the ratio of sensor output before and after controlling the aperture.

As shown in FIG. 1, an endoscope device 20 includes an endoscope 1 for insertion into a subject 30 for observation and a light source device 2 for supplying illumination light to the endoscope 1. The camera 3 is detachably connected to the endoscope 1 and captures an endoscope observation image.

The endoscope 1 has an insertion part 4 inserted into the subject 30 and an operation part having an eyepiece connected to the rear end of the insertion part 4 and connecting the camera 3 at the rearmost end. Part 5,
And a universality Le cable 6 which extends from a side portion of the operation portion 5. Universality Le cable 6 is connected to the light source device 2. An objective lens 7 and a light distribution lens 8 are provided at the tip of the insertion section 4.

[0011] The light distribution lens 8 has at its rear end, the exit end 9a of light guide 9 is provided with, the light guide 9, the insertion portion 4, operation unit 5, through the universality Le cable 6 Have been.

At the rear end of the objective lens 7, an incident end 15a of an image guide 15 is arranged, and this image guide 15 is inserted through the insertion section 4 and the eyepiece of the operation section 5. Then, the emission end 15b of the image guide 15
The eyepiece 16 is disposed on the rear end side, and the subject 30 can be observed with the naked eye from the eyepiece 16.

On the other hand, the light source device 2 includes a lamp 10 for illumination, a condenser lens 11 for condensing illumination light emitted from the lamp 10, and a diaphragm for adjusting the amount of illumination light from the condenser lens 11. 12 are provided. Illumination light from the condenser lens 11 is guided to the entrance end 9b of the light guide 9 via the stop 12, and is irradiated to the subject 30 from the exit end. Further, the light source device 2 includes a drive circuit 13 that drives and adjusts the stop amount of the stop 12 and a drive circuit
And a control circuit 14 for controlling the

The aperture 12 has aperture blades A1 to F1 as shielding members shown in FIG. 4 corresponding to an area assumed to be divided into six portions of an image range described later. The aperture blades A1 to F1 are configured to be able to advance and retreat in the vertical direction with respect to the optical path of the illumination light, and the aperture amount is controlled by the control circuit 13 and the drive circuit 14, so that the illumination light amount is controlled by each illumination described later. The adjustment is made for each area.

The camera 3 has an imaging optical system 17 for imaging the endoscope observation light incident through the eyepiece 16 of the endoscope 1 and an imaging optical system 17 passing through the imaging optical system 17. A beam splitter 18 for separating the endoscope observation light into two, a film 19 for receiving and imaging one of the lights separated by the beam splitter 18, and one of the lights separated by the beam splitter 18 via a light receiving lens 20 , An incident light receiving element 21. The light receiving element 21 is divided into six parts as described later, and each sensor converts the incident light into an electric signal and outputs the electric signal to the light receiving signal generation circuit 22 of the camera 3. The light receiving signal generation circuit 22 receives six electric signals (light amount signals) corresponding to the light amounts of the endoscope image detected by the light receiving element 21, and respectively receives the light source devices 2.
Is output to the control circuit 14.

In the above configuration, the inside of the body cavity 30 is connected to the endoscope 1.
The operation in the case of shooting with will be described. The illumination light emitted from the lamp 10 of the light source device 2 passes through the condenser lens 11, focuses slightly before the entrance end 9 b of the light guide 9, that is, focuses on the center of the stop 12, and enters the entrance end 9 b. The illumination light guided inside the light guide 9 is:
The object 30 is irradiated from the emission end 9a of the light guide 9 to illuminate the inside of the object 30 which is a subject.

Light reflected from the subject 30 enters the objective lens 7. At this time, the angle of view of θ of the reflected light incident on the objective lens 7 shown in FIG.

The reflected light from the subject 30 is transmitted to the objective lens 7
Is formed on the incident end 15a of the image guide 15 through
Through the exit end 15b of the image guide 15, an imaging lens 17 of the camera 3, it passes through the beam scan splitter 18, and the light-receiving lens 20, is again formed on the light receiving element 21.

Meanwhile, the film 19 is imaged the one light separated through the beam scan Puritsu <br/> motor 18 is incident,
An endoscopic image of the subject 30 is displayed.

FIG. 2 shows a state in which the photographing range is assumed to be divided into six areas A0 to F0 on the end face of the image guide 15. It is assumed that the shooting range of the angle of view (solid angle) θ is divided into six parts,
This is for obtaining the brightness for each of the areas F0 to F0.
Then, by obtaining the light amount for each of the six areas, the entire image range is partially overexposed, or
Even if there is underexposure, the amount of illumination light is changed for each area to supply the light to the light guide 15.

FIG. 3 shows a light receiving element 21 in the camera 3.
In the figure, the sensors a0 to f0 divided into six parts are shown. These sensors respectively correspond to the divided areas A0 to F0 of the photographing range shown in FIG. That is, if the six sensors a0 to f0 of the light receiving element 21 correspond to the areas A0 to F0 of the imaging range in position, the brightness of each sensor of the light receiving element 21 for each area of the photographing range. It is detected by. Then, the light receiving signal generation circuit 22 obtains six light quantity signals (a to f shown in FIG. 5) corresponding to the brightness of each area.

FIG. 5 shows the relationship between the areas A0 to F0 and the ratio of the sensor output, where * indicates the state before the aperture control, and * indicates the state after the aperture control. For example, A0, B0, C
Assuming 0 is the near point, the ratio of each signal to the average is
It becomes a graph connected by *-* shown in FIG.

On the other hand, FIG. 4 shows the aperture blades A1 to F1 of the aperture 12 provided in the light source device 2, and furthermore, the incident end face 9b of the light guide 9 on which the illumination light enters corresponds to the areas A0 to F0. And six illumination light areas a1
And b1 show a state in which division is assumed.

The light quantity signals a to f output from the light receiving signal generation circuit 22 are sent to a control circuit 14 of the light source device 2. Activate F1 respectively. The light receiving signals a to f correspond to the respective aperture blades A1 to F1. Therefore, the control circuit 14
According to the brightness of the areas A0 to F0 of the imaging range,
So that the area of the imaging range is uniform within a certain range,
The aperture blades A1 to F1 are operated respectively.

For example, as described above, when the aperture blades A0, B0, and C0 in the photographing range are near points, the amount of light increases, and as shown in FIG. 4, the aperture blades A1, B1, and C1 are used.
Is moved so as to cover the illumination areas a1, b1, c1.

The illumination in the conventional endoscope system is distributed such that the illumination range is as constant as possible. Generally, the brightness is inversely proportional to the square of the distance. Therefore, there is a difference in brightness between a portion at a short distance and a portion at a long distance.

On the other hand, in the present embodiment, the photographing range is divided into a plurality of parts, the brightness is controlled for each area, and the brightness within the angle of view is kept within a certain range.

As described above, in the present embodiment, based on each signal of the multi-divided light receiving element 21 corresponding to the multi-divided imaging range, the multi-divided imaging range is set to have an appropriate light amount. A plurality of aperture blades A of the aperture 12 for light amount adjustment
The drive control of each of 1 to F1 is separately performed. Therefore,
Since the brightness of the photographing range is ensured within a certain range, overexposure or underexposure can be eliminated even when a long distance and a short distance are mixed in one image.

The signals a to f and the aperture blade A
Even if 1 or F1 is not one-to-one,
Control is possible. For example, a microcomputer is mounted on the control circuit 14, the signals a to f are detected in real time, and which blade should be moved by the microcomputer is determined.
This can be realized by controlling the signals a to f so as to be within a certain ratio.

In this embodiment, the case of a multi-divided light receiving element has been described. However, it is needless to say that the present invention can be applied to a TV camera using an image sensor such as a CCD.

Further, in the illustrated example, the area of the imaging range, the sensor of the light receiving element 21, the aperture blade of the aperture 12,
And six illumination areas, respectively, but it is not limited to this number. Further, the area of the imaging range or the like may not be particularly divided evenly.

[0032]

According to the present invention, since the brightness of the photographing range is secured within a certain range, even when a long distance and a short distance are mixed in one image, an overexposed or underexposed portion is obtained. There is an effect that can be eliminated.

[Brief description of the drawings]

FIG. 1 is an overall schematic configuration diagram of the present embodiment.

FIG. 2 is an explanatory diagram showing a division state of a photographing range.

FIG. 3 is an explanatory diagram showing a divided state of a light receiving element in a camera.

FIG. 4 is an explanatory view showing a divided state of an aperture blade and a light guide end face in the light source device.

FIG. 5 is a graph showing a ratio between each area and a sensor output before and after aperture control.

[Description of Signs] 1 ... Endoscope 2 ... Light source device 3 ... Camera 7 ... Objective lens 9 ... Light guide 10 ... Lamp 11 ... Condensing lens 12 ... Aperture A1 to F1 ... Aperture blade 13 ... Drive circuit 14 ... Control circuit DESCRIPTION OF SYMBOLS 16 ... Eyepiece 15 ... Image guide 17 ... Imaging lens 18 ... Beam splitter 19 ... Film 21 ... Light receiving element a0 to f0 ... Sensor 22 ... Light receiving signal generation circuit 30 ... Subject

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Masahiro Hagiwara 2-43-2 Hatagaya, Shibuya-ku, Tokyo Inside the Olympus Optical Co., Ltd. (72) Inventor Hiroshi Tatsuno 2-43-2 Hatagaya, Shibuya-ku, Tokyo Within Olympus Optical Co., Ltd. (72) Inventor Tadayoshi Hara 2-43-2 Hatagaya, Shibuya-ku, Tokyo Inside Olympus Optical Co., Ltd. (56) References JP-A-3-109515 (JP, A) JP Sho 61-18915 (JP, A) Actual opening Sho 62-27318 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) G02B 23/26 A61B 1/06 G03B 9/02 G02B 21 / 06

Claims (1)

(57) [Claims] 1. A endoscope apparatus including an imaging means to image a subject, and the lamp for supplying the irradiation Meiko, received at the incident end face of the illumination light, the subject from the exit end face
A light guide for irradiating a body with a light beam corresponding to the incident end face
And a plurality of radially different light sources with respect to the incident axis of the light guide.
Are arranged for each optical path region, and in a direction intersecting the incident axis.
A plurality of movable diaphragm blades, and a subject irradiated with illumination light through the plurality of optical path regions
For each of the plurality of optical path regions obtained by observation with an endoscope.
Metering a plurality of observation areas corresponding to the plurality of observation areas;
A plurality of light metering means for outputting a plurality of light quantity signals for each of the plurality of aperture blades in accordance with the plurality of light quantity signals;
An endoscope apparatus, comprising: a drive control unit that drives upright .