JPH07136107A - Endoscope apparatus - Google Patents

Abstract

PURPOSE:To always obtain an observation image with a desired brightness by eliminating the need for image brightness adjusting operation by a user during the inspection with an endoscope. CONSTITUTION:A light source device 2 is provided with a dimmer circuit 16 in which a stop 13 is driven to control the quantity of an illumination light from a lamp 11 so that an image brightness signal from a video processor 3 coincides with a desired brightness signal set with a dimmer level adjusting panel 17. A gain increase judging circuit 19 is provided to determine whether the specified desired brightness is higher or lower than an adjusting range of the quantity of the illumination light in the dimmer circuit 16 by judging the position of the stop based on a stop position signal of an output of a stop position detecting circuit 15. When the stop position signal is above a specified value. a signal is sent out to an AGC circuit 9 of the video processor 3 from the gain increase judging circuit 19 to direct an increment or decrement in the gain and the gain is increased or decreased in the video processor 3 to obtain an observation image of a desired brightness.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an endoscope apparatus provided with a brightness control means for endoscope images.

[0002]

2. Description of the Related Art Endoscopes for observing an image of a subject by inserting an elongated insertion portion into a region to be examined such as a body cavity are widely used in the medical field, industrial field and the like.

In an endoscope, illumination light from a light source device is applied to a region to be inspected, an image of the illuminated region to be inspected is formed by an observation optical system, and this is observed with the naked eye from an eyepiece. Alternatively, the observation image is obtained by the image pickup means.

In an endoscope apparatus equipped with such a light source device, the brightness of the image obtained may differ depending on the distance and width of the object, the condition of the object, etc. Therefore, an image of the desired brightness cannot be obtained. There was a possibility that the data could not be obtained or the observation could be hindered. To solve this problem, the brightness of the endoscopic image can be controlled by adjusting the emitted light amount in the light source device according to the brightness of the observed image obtained in the past and adjusting the light amount of the illumination light. Has been adopted.

When the brightness of an endoscopic image is controlled by adjusting the light amount of illumination light, conventionally, a user sets a desired brightness from an operation panel and outputs the set desired brightness signal and a video processor. The image brightness signal is compared, and the light source device performs the dimming operation so that the two signals have the same magnitude. By using the endoscope device having such a configuration, the brightness of the observed image can be kept substantially constant, and an image that is easy to observe can always be obtained.

[0006]

However, as described above, when the brightness control of the endoscopic image is conventionally performed,
Since the user has set the desired brightness from the operation panel and adjusted the illumination light quantity to achieve this desired brightness, an image with the desired brightness cannot be obtained even when the light quantity emitted from the light source device is maximum. In this case, that is, when the user feels that the brightness is lower than the value set by the user and the image is dark, the user himself / herself uses the operation panel to instruct to increase the gain of the amplifier in the video processor. The adjustment operation had to be performed to obtain an image with a desired brightness. For this reason, there is a possibility that the operation of the image brightness control during the endoscopic examination, that is, the dimming level adjustment operation needs to be performed, which may cause a trouble in operating the panel during observation and treatment by the endoscope. was there.

The present invention has been made in view of these circumstances, and it is possible to always obtain an observation image of a desired brightness without requiring the user to adjust the image brightness during an endoscopic examination. An object is to provide an endoscopic device.

[0008]

An endoscope apparatus according to the present invention comprises a light source means for generating illumination light for illuminating a subject, and a video signal processing means for signal processing an image pickup signal of the subject illuminated by the illumination light. And a light quantity adjusting means for adjusting the illumination light quantity of the light source means according to the brightness of the output image of the video signal processing means, and the output image of the video signal processing means has a predetermined target brightness. On the other hand, an image brightness determining unit that determines whether the light amount adjusting unit is brighter or darker than the illumination light amount adjusting range and issues a control instruction of the signal amplification amount in the video signal processing unit based on the determination result. Be prepared.

[0009]

The light quantity adjusting means adjusts the illumination light quantity of the light source means in accordance with the brightness of the output image of the video signal processing means.
At this time, the image brightness determination unit determines whether the output image of the video signal processing unit is brighter or darker than the illumination light amount adjustment range of the light amount adjustment unit with respect to the predetermined target brightness. By giving a control instruction of the signal amplification amount in the video signal processing means based on the result, the illumination light amount can always be adjusted by the light amount adjusting means, and an observation image having a desired brightness can be obtained.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing the configuration of the main part of the endoscope apparatus according to the first embodiment of the present invention.

The endoscope apparatus according to the present embodiment includes an endoscope 1 for obtaining an observation image by inserting an elongated insertion portion into a portion such as a body cavity that cannot be directly observed, and an illumination light for observation to the endoscope 1. A light source device 2 for supplying light, a video processor 3 for signal processing the image signal of the subject obtained by the endoscope 1, and a monitor 4 for receiving an output signal of the video processor 3 and displaying an endoscopic observation image. The main part is configured in preparation.

The endoscope 1 is provided with a light guide 5 for transmitting the illumination light from the light source device 2 to the tip and a solid-state image pickup device 6 such as a CCD for picking up a subject image illuminated by the illumination light. The rear end portion of the light guide 5 is connected to the illumination light emitting portion of the light source device 2, and the solid-state image sensor 6 is connected to the video processor 3 via a signal line.

The video processor 3 includes a signal processing circuit 7 for processing the image pickup signal output from the solid-state image pickup device 6, a drive signal for the solid-state image pickup device 6, a control signal for controlling the operation timing of the signal processing circuit 7, and the like. A control signal generating circuit 8 for generating, an automatic gain control circuit (AGC circuit) 9 for amplifying a video signal output from the signal processing circuit 7 and capable of changing the gain at the time of amplification, and the signal processing circuit 7 An integrating circuit 10 for integrating an output video signal to obtain an image brightness signal
It has and.

The light source device 2 is a lamp 1 for generating illumination light.
1, and a lamp power supply 12 that supplies a current to the lamp 11,
A diaphragm 13 provided in the optical path of the emitted light from the lamp 11 for adjusting the transmission amount of the emitted light to adjust the emitted light amount of the illumination light emitted from the light source device 2, and a diaphragm drive motor 14 for driving the diaphragm 13. Are provided so that the illumination light is incident on the incident end surface of the light guide 5 of the endoscope 1.
The diaphragm 13 has, for example, a plurality of diaphragm blades, and is configured to change the amount of illumination light from the lamp 11 by opening and closing the diaphragm blades.

Further, in the light source device 2, an aperture position detecting circuit 15 for detecting the aperture position of the aperture 13, an aperture position signal detected by the aperture position detecting circuit 15 and an integrating circuit 10 of the video processor 3. A dimming circuit 16 that outputs a diaphragm driving signal based on an image brightness signal or the like is provided, and the dimming circuit 16 causes the video processor 3 to operate.
The diaphragm 13 is changed in accordance with the brightness of the video signal generated in (3) to adjust the illumination light amount of the light source device 2.

In the light source device 2, a dimming level adjusting panel 17 which is an operation panel for performing a dimming level adjusting operation for setting and instructing a desired brightness of an observed image by a user, and a dimming level adjusting. A desired brightness signal setting circuit 18 that outputs a desired brightness signal based on the setting of the panel 17 is provided, and the desired brightness signal is adjusted by the desired brightness signal setting circuit 18 based on the user's dimming level adjustment operation. It is designed to be sent to the circuit 16.

Further, in the light source device 2, it is judged whether or not the diaphragm position signal output from the diaphragm position detection circuit 15 is above a predetermined value, and based on the judgment result, whether or not the gain of the video processor 3 is increased. There is provided a gain-up determination circuit 19 that determines whether or not the gain-up signal is output and outputs a gain-up signal from the gain-up determination circuit 19 when the aperture position signal exceeds a predetermined value.
It is sent to the GC circuit 9 to instruct to increase the gain.

Next, the operation of this embodiment will be described.
When observing a region to be inspected with the endoscope 1, the illumination light from the light source device 2 is emitted to the subject from the tip, the subject image is picked up by the solid-state image pickup device 6, and an image pickup signal is sent to the video processor 3. Output. In the video processor 3, the signal processing circuit 7 performs signal processing to obtain a video signal, which is output to the monitor 4 through the AGC circuit 9 to display an endoscopic observation image.

If the light source device always emits a constant amount of light, the brightness of the obtained image will differ depending on the condition of the subject, and an observation image of constant brightness cannot be obtained. Can not. Therefore, the diaphragm 13 is provided in the optical path of the illumination light, and the image brightness signal obtained from the video processor 3, the diaphragm position signal obtained from the diaphragm position detection circuit 15 indicating the diaphragm position, and the diaphragm speed indicating the moving speed of the diaphragm. The distance from the distal end of the endoscope to the object is controlled by driving and controlling the diaphragm 13 by the light control circuit 16 based on various signals of the desired brightness signal indicating the brightness of the image desired by the user. Even when the state of the subject changes, an observation image of a predetermined brightness desired by the user is always obtained.

That is, a desired brightness of an image is set by performing a dimming level adjusting operation from the dimming level adjusting panel 17, and a desired brightness signal indicating the set brightness and a video processor are set in the dimming circuit 16. 3 and outputs the drive signal to the diaphragm drive motor 14 so that the image brightness signal becomes equal to the desired brightness signal, and monitors the diaphragm position signal from the diaphragm position detection circuit 15. While controlling the diaphragm 13. Thereby, the light source device 2
The amount of illumination light from is adjusted, and an image with a constant brightness is always obtained.

In this embodiment, when the observed image obtained by the video processor 3 is darker than the light amount adjustment range by the light control circuit 16, that is, even if the light control circuit 16 maximizes the light amount, a predetermined brightness cannot be obtained. A gain-up determination circuit 19 for detecting that the aperture 13 is opened to a predetermined value or more based on the aperture position signal is provided as an image brightness determination means. The gain-up determination circuit 19 is provided.
When the diaphragm position signal from the diaphragm position detection circuit 15 is equal to or more than a predetermined value, it is determined that the diaphragm 13 is close to full opening.
At this time, the gain-up determination circuit 19 sends a gain-up signal instructing the gain up to the AGC circuit 9 of the video processor 3 to raise the gain in the video processor 3 so that a bright observation image can be obtained. As a result, it is possible to automatically obtain an image with good brightness desired by the user by adjusting the light amount by the light control circuit 16.

Therefore, even when the user feels that the image of the region to be examined is too dark during the observation with the endoscope, the user does not need to perform the dimming level adjusting operation again, and the desired brightness is always maintained. An observation image can be obtained.

Not only when the observed image is too dark,
Even when the brightness is too bright, the gain up determination circuit 19 is operated in the same manner to adjust the gain of the video processor 3 to obtain an observation image having a desired brightness. That is, when the desired brightness set by the dimming circuit 16 as the minimum light quantity is not obtained and the brightness is brighter than the light quantity adjustment range, the gain-up determination circuit 19 detects that the diaphragm position signal is equal to or less than the predetermined value and stops the diaphragm. 1
AGC of video processor 3 is judged to be close to fully closed
A signal for instructing the gain down is sent to the circuit 9 to lower the gain in the video processor 3. As a result, even if the user feels that the brightness is too bright, the image of the desired brightness is automatically obtained by the light amount adjustment by the light control circuit 16.

As described above, according to the present embodiment, even when the image of the desired brightness cannot be obtained due to the light amount adjustment range of the dimming circuit 16 and the image is too dark or too bright,
The gain of the video processor 3 can be controlled to always obtain an observation image with a desired brightness, and the user's dimming level adjustment operation during endoscopic examination can be eliminated. As a result, the number of operations in the endoscopy can be reduced and the operations can be simplified, and the user can concentrate more on the diagnosis, treatment, etc., so that the endoscopy can be performed more safely and reliably.

FIG. 2 is a block diagram showing the structure of the main part of the endoscope apparatus according to the second embodiment of the present invention.

In the second embodiment, the configuration of the image brightness determining means for controlling the gain of the video processor by determining whether the image is too bright or too dark is modified. As a determination means, a comparison circuit 22 that compares the image brightness signal from the video processor 3 with a set desired brightness signal, a count circuit 23 that counts the output of the comparison circuit 22, and a comparison circuit 22.
And a reset circuit 24 that resets the count circuit 23 by the output of the. The configuration of the other parts is the same as that of the first embodiment, and the description is omitted.

In the present embodiment, as in the first embodiment, the desired brightness signal set by performing the dimming level adjusting operation on the dimming level adjusting panel 17 and the integrating circuit 1 of the video processor 3 are set.
Based on the image brightness signal from 0, the dimming circuit 16 controls the diaphragm 13 to perform the dimming operation. At the same time, the comparison circuit 22 compares the desired brightness signal with the image brightness signal, and inputs the comparison result to the count circuit 23.

The counting circuit 23 counts the period in which the image brightness signal is darker than the desired brightness signal, and when the dark state continues for a certain period of time or more, it is determined that the diaphragm 13 is kept fully open. . At this time, the count circuit 23 sends a gain-up signal for instructing gain-up to the AGC circuit 9 of the video processor 3 to raise the gain in the video processor 3 so that a bright observation image can be obtained. When the image brightness signal becomes brighter than the desired brightness signal, the reset circuit 24 resets the count circuit 23 and the gain-up signal stops. Even when the observed image is too bright, the gain of the video processor 3 is similarly lowered so that the observed image having the desired brightness can be obtained.

As described above, also in this embodiment, as in the case of the first embodiment, the light amount adjustment by the light control circuit 16 can automatically obtain an image with good brightness desired by the user. Even when the user feels that the image of the site to be examined is too dark or too bright during observation with a mirror, the user does not need to perform the dimming level adjustment operation again, and always obtains the observation image of the desired brightness. It becomes possible.

By the way, in the endoscope device, when the light source lamp of the light source device becomes unusable during observation, an emergency light is turned on to prevent the observation from becoming impossible, and the endoscope insertion portion is safely removed. Some have been configured to do so. FIG. 3 shows an example of the configuration of an endoscope apparatus equipped with a light control means when using an emergency light.

The light source device 31 is provided with a main light source lamp 32 such as a xenon short arc lamp and an emergency light 33 such as a halogen lamp. The light source lamp 32 and the emergency light 33 are connected via a lamp switching circuit 34. Connected to the power source 35. If the xenon short arc lamp or the like used as the light source lamp 32 becomes unusable due to some reason, for example, the lamp burns out,
The lamp switching circuit 34 switches the connection of the lamps,
As the emergency light 33, a halogen lamp darker than the xenon short arc lamp is used.

Here, since the emergency lamp 33 is darker than the light source lamp 32 by simply switching the lamps, when the brightness setting of the dimming level adjusting panel 17 is low, the user again performs the dimming level adjusting operation. Otherwise, it may happen that an image with desired brightness cannot be obtained. That is, even in an emergency, it is necessary to perform a dimming level adjusting operation other than the operation of the endoscope, which may complicate the operation. Therefore, in this example, the emergency light usage state is controlled by the dimming circuit 16 of the light source device 31 and the AGC of the video processor 3.
By notifying the circuit 9 and further providing an emergency light AGC setting section 36 as a gain adjusting means for using the emergency light, the brightness of the image when using the emergency light is controlled. The configuration of the other parts is similar to that of the first embodiment shown in FIG. 1, and the description thereof is omitted.

When the light source lamp 32 becomes unusable during the observation by the endoscope 1, the lamp switching circuit 34 switches to the emergency light 33, and the emergency light use signal indicating the emergency light use state is sent to the AGC circuit 9 and the dimming control. It is sent to the circuit 16. With this emergency light use signal, the dimming circuit 16 forcibly opens the diaphragm 13 fully, and the AGC circuit 9 forcibly turns on the automatic gain control. Also at this time,
A gain control signal is sent from the emergency light AGC setting unit 36 to the AGC circuit 9 to enable gain adjustment when using the emergency light so that a brighter observation image can be obtained even when the emergency light is used.

With this structure, a bright and good observation image can be obtained only by adjusting the gain of the video processor 3 even when the emergency light is used, and the adjustment can be made when the endoscope insertion portion is removed in an emergency. The operation can be simplified because the light level adjustment operation is unnecessary. Therefore, the endoscope insertion portion can be more safely removed from the site to be examined, and the safety in an emergency can be improved.

Next, FIG. 4 and FIG. 5 show an example of the configuration of an endoscope apparatus provided with a light emission amount control means for a light source lamp.

FIG. 4 shows a first endoscope apparatus equipped with a light emission amount control means for controlling the light emission amount of a light source lamp according to the position of a diaphragm.
FIG. The light source device 41 is provided with a lamp current control circuit 43 that controls the drive current of the light source lamp 42 by the position of the diaphragm blades of the diaphragm 13, and is connected to a power supply 44 for the lamp.

If the lamp is turned on at the maximum rating regardless of the diaphragm position, there is a possibility that the light emitted from the lamp cannot be fully closed and the light cannot be adjusted to the target brightness when the diaphragm blade is fully closed. Further, it is difficult to extend the life of the lamp if the lamp is always turned on at the maximum rating. Therefore, in this example, based on the diaphragm position signal detected by the diaphragm position detection circuit 15, the lamp current control circuit 43 controls the lamp current according to the diaphragm position to control the light emission amount of the light source lamp 42. ing.
The configuration of the other parts is similar to that of the first embodiment shown in FIG. 1, and the description thereof is omitted.

When the light source lamp 42 is turned on, first, the position of the diaphragm 13 controlled by the dimming circuit 16 is detected by the diaphragm position detection circuit 15, and the diaphragm position signal is sent to the lamp current control circuit 43. At this time, the lamp current control circuit 43 lowers the lamp current supplied to the light source lamp 42 to reduce the light emission of the lamp when the diaphragm is narrowed down by a predetermined value or more, that is, when the diaphragm is close to full closure based on the diaphragm position signal. Try to keep the amount down.

With this structure, the diaphragm can be effectively operated in the entire area where the diaphragm blades move, and the dimming circuit 16 can always perform the dimming so that the desired brightness can be obtained without the need for the dimming level adjusting operation. It is possible to obtain an observation image of.
Further, it is possible to provide a period in which the light source lamp emits light with a driving current lower than the maximum rating, and it is possible to extend the life of the lamp.

FIG. 5 shows a second configuration example of the endoscope apparatus provided with the light emission amount control means of the light source lamp. Second
The light source device 45 of the above configuration example is provided with a count circuit 46 that counts the output of the aperture position detection circuit 15 and a reset circuit 47 that resets the count circuit 46 by the output of the aperture position detection circuit 15. The lamp current control signal is sent to the lamp current control circuit 43 by counting the period in which the diaphragm is narrowed by a predetermined value or more. The configuration of the other parts is the same as that of the first configuration example described above.

When the light source lamp 42 is turned on, first, the position of the diaphragm 13 controlled by the dimming circuit 16 is detected by the diaphragm position detection circuit 15, and the diaphragm position signal is sent to the counting circuit 46. Based on the diaphragm position signal, the counting circuit 46 counts a period in which the diaphragm is narrowed by a predetermined value or more and detects that this state has continued for a certain period of time. At this time, the lamp current control signal is output. Then, the lamp current control circuit 43 reduces the lamp current supplied to the light source lamp 42 to suppress the amount of light emitted from the lamp. Then, when the aperture is opened by a predetermined value or more, a reset signal is output from the reset circuit 47 to reset the count circuit 46, and the lamp current output from the lamp current control circuit 43 is returned to a steady state.

With this configuration, as in the first configuration example, it is possible to always obtain an observation image of the desired brightness without the need for adjusting the dimming level and to extend the life of the lamp. In addition to this, there is an effect that the diaphragm control in the dimming operation can be performed more stably.

Next, FIG. 6 shows an example of the configuration of an endoscope apparatus equipped with gain setting means for setting the gain of the video processor according to the combination of the video processor and the light source device.

In the endoscope and the video processor, the output level of the image brightness signal with respect to the amount of incident light differs depending on the product, so that the response speed differs when the automatic light control is performed by using the image brightness signal in combination with the light source device. May occur. Therefore, in this example, a level setting means for keeping the level of the image brightness signal for a predetermined amount of illumination light constant is provided so that the response speed during the dimming operation is kept constant so that the optimum response speed is always obtained.

The video processor 51 includes a solid-state image pickup device 6
Signal processing circuit 52 for processing the image pickup signal of the output of
A control signal generating circuit 53 for generating a control signal for controlling the solid-state image sensor 6 and the video signal processing circuit 52; and a video signal output from the video signal processing circuit 52 is integrated to obtain an image brightness signal. An integrating circuit 54 and a gain control amplifier (GCA) that amplifies the output signal of the integrating circuit 54.
55 and.

The light source device 56 includes a lamp 57 for generating illumination light, a diaphragm 58 provided in the optical path of the light emitted from the lamp 57 for adjusting the amount of emitted light, and a diaphragm drive circuit 59 for driving the diaphragm 58. And an aperture position detection circuit 60 for detecting the position of the aperture 58. The aperture position detection circuit 60 adjusts the amount of illumination light supplied to the endoscope 1 by opening and closing the aperture 58. 5
The position of 8 is detected.

Further, a CPU 61 for controlling each part, a half mirror 62 which can be inserted into and removed from the optical path of the illumination light, a light receiving element 63 for receiving the light reflected by the half mirror 62,
Comparator (1) for comparing the output of the light receiving element 63 with a reference signal
64, a comparator (2) 65 for comparing the output of the GCA 55 of the video processor 51 with a reference signal, and the diaphragm drive circuit 5
A changeover switch 66 for changing over the input of 9 is provided to adjust the level of the image brightness signal with respect to a predetermined illumination light amount at the initial operation.

Further, an arithmetic circuit 67 for correcting the image brightness signal output from the GCA 55 according to the aperture position signal from the aperture position detection circuit 60, and a dimming level adjustment panel 68.
A comparator (3) 69 is provided for comparing the desired brightness signal set by the above with the image brightness signal corrected by the arithmetic circuit 67, and the diaphragm 58 is provided according to the output of the comparator (3) 69.
The dimming operation is performed by controlling the.

When the power of the apparatus is turned on, first, the CPU
Reference numeral 61 denotes a driving instruction for the half mirror 62, which is inserted in the optical path of the illumination light, and the light split by the half mirror 62 is received by the light receiving element 6.
Photoelectric conversion is performed at 3 to obtain a light amount signal. And comparator (1)
The light quantity signal is compared with a reference signal by 64, and an error signal is input to the diaphragm drive circuit 59 through the changeover switch 66 to drive the diaphragm 58 so that the light quantity signal output from the light receiving element 63 and the reference signal match. To do. In this way, a predetermined amount of illumination light is emitted from the light source device.

In this state, the level of the image brightness signal obtained by the video processor 51 is adjusted to a predetermined value. At this time, a cap-shaped jig 70 having a fixed reflectance as shown in FIG. 7 is attached to the distal end portion of the insertion portion of the endoscope 1 so that an image having a predetermined brightness is captured by the solid-state image sensor 6. . Then, based on the video signal output from the video signal processing circuit 52, the image brightness signal obtained by the integrating circuit 54 and the GCA 55 is compared with the reference signal by the comparator (2) 65, and the error signal is input to the GCA 55. The gain of the GCA 55 is adjusted so that the image brightness signal has a predetermined value. For example, when the image brightness signal is larger than the reference signal, the gain of the GCA 55 is adjusted to be small so that the ratio of the image brightness signal output from the video processor 51 to the illumination light amount becomes constant.

When the gain of the GCA 55 is set so that the image brightness signal coincides with the reference signal, and the output of the comparator (2) 65 becomes 0, the CPU 61 sends an instruction to the half mirror 62 so that the illumination light is in the optical path. Withdraw further, switch the selector switch 66 to the comparator (3) 69 side, and then the comparator (1)
The operation of 64 is stopped. In this state, since the ratio of the output image brightness signal to the illumination light amount is constant in the video processor, the gain for the light control unit of the light source device is constant. Therefore, it is possible to suppress the variation in the response speed of the light control means depending on the type of the video processor, and it is possible to always perform the light control at the optimum response speed.

During the dimming operation, the video processor 51
, The video signal is integrated by the integration circuit 54, and GCA5
In step 5, the image brightness signal amplified with the amplification degree set as described above is input to the light source device 56. In the light source device 56, first, the arithmetic circuit 67 corrects the image brightness signal according to the level of the aperture position signal output from the aperture position detection circuit 60. This diaphragm position signal uses, for example, the output of a potentiometer that is provided coaxially with the drive shaft of the motor that moves the diaphragm blades or that is interlocked via a gear, or detects the tilt of the coil of the diaphragm drive motor with a Hall element. It can be obtained by obtaining the aperture angle. In the arithmetic circuit 67, an address corresponding to the level of the aperture position signal is generated one-to-one, data corresponding to this address is read out from a prestored memory, and the correction data and the image brightness signal are integrated. To do.

The image brightness signal corrected by the arithmetic circuit 67 is compared with the desired brightness signal set by the user on the dimming level adjusting panel 68 by the comparator (3) 69, and the differential signal is changed over. It is input to the diaphragm drive circuit 59 via 66. The diaphragm drive circuit 59 outputs a drive current according to the difference signal to drive the diaphragm 58 and increase or decrease the light emitted from the light source lamp 57. As a result, the image brightness signal output from the video processor 51 is increased or decreased, and the illumination light amount is controlled so as to match the desired brightness signal.

With this configuration, the level setting means for making the level of the image brightness signal for a predetermined illumination light amount constant in each video processor makes the gain for the light adjusting means of the light source device constant and the light adjusting operation. Therefore, the response of dimming in the combination of the video processor and the light source device can be optimized. Therefore, there is no problem that the response speed differs depending on the video processor, and it is possible to always perform the optimum light control operation without requiring a complicated operation.

In this example, the initial operation of setting the level of the image brightness signal for a predetermined light amount is started when the power of the apparatus is turned on, but the initial operation is started by an instruction from the outside of the user. You may do it.

[0056]

As described above, according to the present invention, it is possible to always obtain an observation image of a desired brightness without requiring the user to adjust the image brightness during an endoscopic examination. is there.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a main part of an endoscope apparatus according to a first embodiment of the present invention.

FIG. 2 is a block diagram showing a configuration of a main part of an endoscope apparatus according to a second embodiment of the present invention.

FIG. 3 is a block diagram showing a configuration example of an endoscope apparatus including a light control unit when an emergency light is used.

FIG. 4 is a block diagram showing a first configuration example of an endoscope apparatus including a light emission amount control unit of a light source lamp.

FIG. 5 is a block diagram showing a second configuration example of an endoscope apparatus including a light emission amount control unit of a light source lamp.

FIG. 6 is a block diagram showing a configuration example of an endoscope apparatus including a gain setting unit that sets a gain of a video processor according to a combination of apparatuses.

FIG. 7 shows a jig to be mounted on the distal end portion of the endoscope insertion portion when adjusting the level of the image brightness signal for a predetermined illumination light amount at the time of initial operation, (a) is a perspective view,
(B) is a sectional view

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Endoscope 2 ... Light source device 3 ... Video processor 7 ... Signal processing circuit 9 ... AGC circuit 10 ... Integration circuit 11 ... Lamp 13 ... Aperture 15 ... Aperture position detection circuit 16 ... Dimming circuit 17 ... Dimming level adjusting panel 18 ... Desired brightness setting circuit 19 ... Gain up determination circuit

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[Procedure amendment]

[Submission date] January 13, 1994

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 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Akira Taniguchi 2-43-2 Hatagaya, Shibuya-ku, Tokyo Olympus Optical Co., Ltd. (72) Inventor Sumiyo Uchimura 2-43-2 Hatagaya, Shibuya-ku, Tokyo Olympus Optical Co., Ltd. (72) Inventor Hideki Koyanagi 2-43-2 Hatagaya, Shibuya-ku, Tokyo Olympus Optical Co., Ltd.

Claims (1)

[Claims] 1. An endoscope apparatus comprising: a light source unit for generating illumination light for illuminating a subject, and a video signal processing unit for signal-processing an image pickup signal of the subject illuminated by the illumination light. Light amount adjusting means for adjusting the illumination light amount of the light source means according to the brightness of the output image of the signal processing means, and illumination in the light amount adjusting means for the output image of the video signal processing means having a predetermined target brightness. An image brightness determination means for determining whether the brightness is higher than or equal to the light amount adjustment range and for giving an instruction to control the signal amplification amount in the video signal processing means based on the determination result, Mirror device.