JPS6260548A - Endoscope apparatus - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to an endoscope device capable of taking TV pictures of the inside of a living body cavity and simultaneously irradiating a laser beam into the subject's body as necessary.

[Technical background of the invention and its problems]

In recent years, endoscopic devices have appeared that allow television viewing of the inside of a living body cavity by incorporating a small solid-state image sensor into the tip of the scope. In order to keep the brightness constant, some devices are equipped with an automatic light amount control circuit (hereinafter referred to as ALC) that automatically controls the amount of illumination light depending on the brightness of the observation site.

Therefore, there is a demand for endoscope devices that can not only observe the inside of a living body cavity, but also perform treatment at the same time. The laser scalpel method introduced has been used. However, if this request is applied to an endoscope device with ALC, the following problem will occur.

That is, when the laser beam is irradiated, the illuminance of the observation area temporarily increases, so the ALC works to darken the screen in order to balance the brightness of the entire screen, and as a result,
This causes a problem in that the observation field of the area other than the area irradiated with the laser beam becomes dark. Another problem is that the reaction speed of ALC is generally not that fast, so when the laser light irradiation is finished, the entire screen is under-lit, and it takes time for the entire screen to return to its normal brightness. Become. The latter problem can be solved by increasing the reaction speed of the ALC, but in this case, another problem arises in that the screen flickers excessively and becomes difficult to see.

[Purpose of the invention]

The present invention has been made based on the above circumstances, and its purpose is to prevent the field of view other than the irradiated area from becoming dark even when a laser is irradiated in an endoscope device, and to prevent the laser from being turned off. To provide an endoscope device in which the entire screen does not become dark even after the screen is turned off.

[Summary of the invention]

The outline of the present invention is to achieve the above object by fixing the amount of illumination light irradiated to the observation site during treatment.
An object of the present invention is to configure an endoscope device that can maintain the illuminance of the observation field other than the irradiated area at a normal brightness even during laser beam irradiation.

[Embodiments of the invention]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing an example of an endoscope apparatus according to the present invention.

1 is a scope of an endoscope device inserted into a living body cavity;
A solid-state image pickup device and an optical system (both not shown) for forming an image on the solid-state image pickup device are incorporated in the tip thereof.

Reference numeral 5 denotes an illumination light generation device which is equipped with a light amount control device 5A described later, and the illumination light emitted here is introduced into the scope 1 through the light guide 8, and is used to observe the inside of the living body cavity from the tip of the scope. It is designed to illuminate the area.

Reference numeral 6 denotes a laser light generating device, which operates to emit laser light only when it is necessary to irradiate the inside of the body cavity with laser light.

The laser light emitted here is introduced into the scope 1 through the laser guide 9, and is irradiated into the living body cavity from the tip of the scope.

Reference numeral 2 denotes a video processing device, which emits a drive signal to the solid-state image sensor in the scope 1, and converts the video signal output from the solid-state image sensor based on the drive signal into a display video signal (video signal). The converted signal is then output to a display device (video monitor) 3 and a light amount control signal generator 4.

In this embodiment, the automatic light amount control circuit includes a light amount control signal generation device 4 and the light amount control device 5A, and the light amount control signal generation device 4 is configured to generate a video signal based on a signal from the video processing device 2. A signal is sent to the light amount control device 5A to maintain the screen image at a constant brightness. That is, when the output signal from the video processing device 2 is small and the video screen is dark, a signal is sent to the light amount control device 5A to increase the amount of illumination light, and the output signal from the video processing device 2 is large and the video screen image is too bright. At this time, a signal is issued to the light amount control device 5A to reduce the amount of light. Based on this signal, the light amount control device 5A controls the amount of illumination light sent to the light guide 8 using appropriate means such as an aperture or a shutter for controlling the illumination time. More specifically, for example, as shown in FIG. 2, the light amount control signal generating device 4 includes a rectifier 41, a reference signal generator 42, and a comparator 43. In this case, the rectifier 41 converts the video signal from the video processing device 2 into a DC signal, and the comparator 43 converts the video signal from the video processing device 2 into a DC signal.
The reference signal generator 42 outputs a DC signal as a reference signal to the comparator 43. Then, the comparator 43 compares both signals and outputs the result to the light amount control device 5A. Further, the light amount control device 5A is adapted to control a light amount limiting value such as a current value given to the diaphragm based on the output voltage from the comparator 43.

Now, the fixing device for fixing the amount of illumination light is composed of a sample hold circuit 7 and a changeover switch 10. The changeover switch 10 has two contacts a.

The switch 10 itself is connected to the laser beam generator 6. The switch 10 itself is connected to the laser beam generator 6. This changeover switch 10 is normally connected to contact a, so that the signal output from the light amount control signal generator 4 is input to the light amount control device 5A without passing through the sample and hold circuit 7. . However, when irradiating a laser beam, the contact is switched in response to a signal to irradiate the laser beam from the laser beam generator 6, and the signal from the light amount control signal generator 4 is transmitted to the sample hold circuit 7. The amount of illumination light is held at the value at that time. This is because the amount of illumination light to the observation site does not change even during laser light irradiation. Also,
When the laser beam is turned off at the end of the treatment, a switching signal is issued from the laser beam generator 6 with a slight delay.
It is configured to receive this signal and switch to the contact a side again.

Here, the reason why the switching signal is issued with a slight delay is to take into consideration that the reaction speed of the automatic light amount control circuits 4 and 5A is slow. In other words, if you switch to contact a at the same time as turning off the laser beam, since the reaction speed of the automatic light amount control circuit is slow, the light amount will be controlled based on the signal at the time of laser beam irradiation, and after turning off the laser beam irradiation. This is because the light amount is still controlled in the direction of reducing the amount of light and the screen becomes dark. Therefore, the delay time is, for example, when the light amount control signal generator 4 outputs a signal on the average of several frames. The delay is made by a time equivalent to the number of frames.

According to the endoscope device as described above, since the changeover switch 10 is normally connected to the contact a, the brightness of the image is kept constant and the inside of the body cavity can be observed well, and the necessary Even when the laser beam is irradiated in accordance with There is no. Moreover, since the switching switch 0 is automatically switched to the contact point a after a predetermined time delay even after the laser beam irradiation is turned off, it is possible to prevent the image from becoming dark due to insufficient light quantity immediately after the laser beam is turned off.

Next, if the video screen becomes extremely dazzling when irradiated with laser light, the brightness of the video screen may be corrected as follows. FIG. 3 shows an embodiment for achieving this purpose, in which a regulating device is provided to limit the maximum level of the video signal of the display device.

In FIG. 3, the regulating device is composed of a changeover switch 11, a peak limiter circuit 12, and a reramp circuit 15.

The changeover switch 11 is interposed between the video processing device 2 and the display device 3, and has two contacts a and b, one of which is connected to the peak limiter circuit I2 via the clamp circuit 15. The other contact point bq is connected to the display device 3. Furthermore, the Sui and Sochi II themselves are connected to a laser beam generator 6. This changeover switch 11 is
Normally, it is connected to the contact A side, but when irradiating laser light, it is switched to the contact A side upon receiving a signal from the laser light generator to irradiate the laser light.

Therefore, the video signal output from the video processing device 2 (
Normally, the video signal (video signal) is input to the display device 3 without passing through the peak limiter circuit 12, but when it is irradiated with laser light, it passes through the peak limiter circuit 12 and its maximum level is reduced as shown in FIG. will be input to the display device 3 in a limited manner. This prevents the video screen from becoming dazzling. FIG. 5 is a block diagram showing a regulating device of a different type from that shown in FIG. 3.

The regulation device in the figure is composed of a T correction circuit 13 and a T correction controller 14. The T correction circuit 13 is interposed between the video processing device 2 and the display device 3, and the T correction controller 14 is , γ correction circuit 13 and laser light generator 6
It is interposed between.

Now, the T correction controller 14 normally controls the γ correction circuit 13 so that the input signal-output signal line becomes a straight line as shown by the solid line in the graph of FIG. By receiving the medium signal, the gamma correction circuit 13 is controlled so that the input signal-output signal line forms a curve with a decreasing rate of increase from point A, as shown by the broken line in FIG.

Therefore, during laser beam irradiation, the video signal from the video processing device 2 is input to the display device 3 in a restricted manner as shown by the broken line in FIG. This prevents the video screen from becoming dazzling.

Although each embodiment of the present invention has been described above, it goes without saying that the present invention is not limited to the above embodiments, and can be modified as appropriate within the scope of the gist of the present invention.

For example, switches 10.11 may be manually operated.

〔Effect of the invention〕

As detailed above, according to the present invention, even when laser light is irradiated, the amount of illumination light is fixed by the fixing device.
On the video screen, the area around the laser light illumination part does not become dark, and in some cases even after the laser light is turned off, the release of the fixing device is delayed for a predetermined period of time to prevent the entire video screen from becoming dark. can.

Furthermore, if necessary, the maximum level of the video signal to the display device can be limited during laser beam irradiation, so in this case the video screen will not be dazzling and you will always be able to see a good endoscopic image. can be provided.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an example of the endoscopic device of the present invention;
FIG. 2 is a block diagram showing an example of an automatic light amount control circuit, FIG. 3 is a partial block diagram showing an example of an endoscope device of the present invention provided with a regulating device, and FIG. 4 is an explanatory diagram of the same operation. FIG. 5 is a block diagram showing a regulating device different from that in FIG. 3, and FIG. 6 is an explanatory diagram of the same operation. l...Scope, 3...Display device, 4.5A...
Automatic light amount control circuit, 5... illumination light generator,
6... Laser generator, 7.10... Fixing device, 11.12, 15, 13.14... Regulating device. Agent Patent Attorney Norio Chika Yudo Norio Ogo Figure 3 Figure 4

Claims (2)

[Claims] (1) In an endoscope device capable of illuminating an observation site via a scope inserted into a living body cavity and, if necessary, irradiating a therapeutic laser beam to an affected area within the observation site range, the observation site a display device for displaying a video image from the site; an illumination generator for illuminating the observation site; a laser light generation device for irradiating the affected area with laser light if necessary; and illumination for the observation site. An endoscope device comprising: an automatic light amount control circuit that controls the amount of light; and a fixing device that fixes the amount of illumination light during laser beam irradiation. (2) The endoscope device according to claim 1, further comprising a regulating device that limits the maximum level of the video signal to the display device during laser beam irradiation.