JPH0690900A - Electronic endoscope apparatus - Google Patents

Abstract

PURPOSE:To provide an electronic endoscope apparatus which enables the changing of the optimum signal processing of an image pickup signal corresponding to information pertaining to an illumination light generating means. CONSTITUTION:An electronic endoscope apparatus 1 judges the type of a light source and operating condition with a judging circuit 19 by a judging signal to be outputted from a judging signal generator 18 and switches a processing operation of an image signal processing circuit 9 according to the results of the judgment to make itself correspond to the type of the light source and the operating condition. The image signal processing circuit 9 performs a proper signal processing operation according to the type of the light source thereby preventing degrading in the quality of picture.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic endoscope apparatus which can be inserted into a subject to observe the inside.

[0002]

2. Description of the Related Art In recent years, by inserting an elongated insertion portion into a body cavity, the organ in the body cavity can be observed and, if necessary,
2. Description of the Related Art Endoscopes that can perform various therapeutic treatments using a treatment instrument inserted in a treatment instrument channel are widely used.

Boilers, gas turbine engines,
BACKGROUND ART Industrial endoscopes are widely used for observing and inspecting scratches and corrosion inside pipes of chemical plants and the body of automobile engines.

Further, various electronic endoscopes using a solid-state image pickup device such as a charge coupled device (CCD) as an image pickup means are also used.

FIG. 2 shows an example of the configuration of an electronic endoscope apparatus using the electronic endoscope 81. This electronic endoscope 8
1 has an elongated and flexible insertion portion 82, and a large diameter operation portion 83 is connected to the rear end of the insertion portion 82. A flexible cable 84 extends laterally from the rear end of the operation portion 83, and a connector 85 is provided at the tip of the cable 84. The electronic endoscope 81 has a video processor 8 in which a light source device as illumination light generating means and a signal processing circuit are built in via the connector 85.
6 is connected. Further, a monitor 87 is connected to the video processor 86.

A hard tip portion 89 and a bendable bending portion 90 adjacent to the rear side of the tip portion 89 are sequentially provided on the tip end side of the insertion portion 82. In addition, the endoscope 81 has a bending operation portion knob 9 provided on the operation portion 83.
By rotating 1 the bending portion 90 can be bent in the left-right direction or the up-down direction.
Further, the operation portion 83 has an insertion opening 92 communicating with a treatment tool channel (not shown) provided in the insertion portion 82.
Is provided.

As shown in FIG. 1, a light guide 94 for transmitting illumination light is inserted into the insertion portion 82 of the electronic endoscope 81. The tip end surface of the light guide 94 is arranged at the tip end portion 89 of the insertion portion 82, and the illumination light can be emitted from the tip end portion 89. Further, the incident end side of the light guide 94 is inserted into the universal cord 84 and connected to the connector 85. An objective lens system 95 is provided at the tip portion 89, and a solid-state image sensor 96 such as a CCD is provided at the image forming position of the objective lens system 95. The solid-state image sensor 96 has sensitivity in a wide wavelength range from the ultraviolet region to the infrared region including the visible region. The solid-state image sensor 96 includes a signal line 7
1, 72 are connected, and these signal lines 71, 72 are inserted into the insertion portion 82 and the universal cord 84 and connected to the connector 85.

On the other hand, in the video processor 86, there is provided a lamp 73 as an illumination light source which emits a wide band light from ultraviolet light to infrared light. As the lamp 73, a general xenon lamp, strobe lamp, halogen lamp or the like can be used. The xenon lamp, strobe lamp, and halogen lamp emit a large amount of not only visible light but also ultraviolet light and infrared light. This lamp 73
The power is supplied from the power supply unit 77. The light emitted from the lamp 73 is incident on the incident end of the light guide 94, guided to the tip 89 through the light guide 94, emitted from the tip 89, and illuminates the observation site. Has become.

The return light from the observation site due to the illumination light is imaged on the solid-state image pickup device 96 by the objective lens system 95 and photoelectrically converted. A drive pulse from the driver circuit 70 in the video processor 86 is applied to the solid-state imaging device 96 via the signal line 71. The solid-state imaging device 96 is adapted to read out a video signal by this drive pulse and transfer it.

The video signal read out from the solid-state image pickup device 96 is inputted to the preamplifier 74 provided in the video processor 86 or the electronic endoscope 81 via the signal line 72. ing. The video signal amplified by the preamplifier 74 is input to the process circuit 75, subjected to signal processing such as γ correction and white balance, output as R, G, B color signals, and input to the encoder 76. It is like this. From this encoder 76, R, G, B color signals are converted to N
A TSC composite signal is output.

Here, the white balance operation is, for example,
When the white subject is imaged, the output RGB signals are controlled to have the same value.

The R, G, B color signals or N
The TSC composite signal is input to the color monitor 87, and the color monitor 87 displays the observed region in color.

[0013]

In the case of the conventional example, when the type of the light source as the illumination light generating means information, for example, the type of the lamp is changed, the following drawbacks can be considered.
The typical xenon (Xe) lamps and halogen lamps described above are typical endoscope lamps. The radiant energy distribution is different between the xenon lamp and the halogen lamp, and the color temperature is also different by about 2000K. If the color temperatures are so different, even if the white balance adjustment is performed and the color reproduction of only white is adjusted, the color reproduction of the other colors becomes poor. In general, a xenon lamp is used as a normal lamp and a halogen lamp is used as an emergency lamp.

Further, among different types such as an illumination (imaging) system which is a type of a light source as the illumination light generating means information, for example, a frame sequential system or a single plate color system (hereinafter sometimes referred to as simultaneous system). , The signal processing method had to be changed, and the conventional example could not cope.

In medical endoscopes in the field of use of endoscopes, since the subject is the inner wall of the body and the like, the color feature is a reddish relatively dark color. Therefore, when the distance between the tip of the endoscope and the subject becomes large, the illumination light emitted from the light guide is often reflected on the inner wall and then irradiated to the subject. Therefore, the colors of the subject are more reddish than they actually are. The image is affected by so-called secondary reflected light.

On the other hand, some light source devices are provided with a light amount adjusting means such as a diaphragm for obtaining an appropriate light amount. The color of the illumination light emitted from the lamp may change depending on the diaphragm position, which is one of the operating states of the light source, or the deviation between the diaphragm and the optical axis. Therefore, even if the white balance is adjusted, there is a drawback that the aperture changes depending on the brightness of the subject and the change in the aperture changes the overall color.

In the case of a frame-sequential electronic endoscope, a rotary filter for color separation is arranged inside the light source. When the rotating filter for color separation is replaced, the color reproducibility of the obtained image depends on the variation of the spectral characteristic of the filter. In the device of the conventional example, the correction of the variation of the color separation filter is adjusted only by the white balance, and the correction of the color important for the endoscopic diagnosis is not sufficient.

Further, there is a light source device having three kinds of illumination modes of a frame sequential system, a single plate color system, and an optical fiber endoscope, and the mode is selected according to the type of endoscope and processor used in combination. I used it after switching. When a processor capable of supporting both the frame sequential method and the simultaneous method is used in combination with the light source device, it is desired to have a system that allows efficient and correct setting of each device and has good operability.

Further, in the electronic endoscope apparatus capable of processing the image pickup signals obtained by both the frame sequential method and the simultaneous method, the forms of the signals obtained by the both methods are different. For this reason,
As signal processing, for example, white balance processing operation and the like need to be changed according to the above method.

Further, according to the difference between the modes of the frame sequential type and the simultaneous type, which is one of the operating states of the light source, the A on the processor side is
In GC (auto gain control), it is necessary to change the detection method for generating a signal for controlling the gain.

Alternatively, in the conventional electronic endoscope apparatus, depending on whether it is a light source for field sequential illumination light or a light source for white light illumination, CC
Since the drive of D could not be changed, the resolution was reduced and the dynamic range was reduced.

Further, even in the light source device of the frame-sequential type, if the rotation speed of the rotary filter for separating the illumination light into a plurality of different wavelength bands changes, color mixing occurs. Further, if the aperture ratio of the optical filter arranged in the rotary filter changes, light leakage may occur, or flicker or color mixture may occur. Furthermore, even if the order or arrangement of the colors of the optical filters is changed, color mixing occurs. These are also one of the operating states of the light source.

Further, some electronic endoscope apparatuses use special light such as infrared rays for the purpose of blood flow observation, for example, in addition to imaging using frame sequential illumination light or white illumination light.

In the case of performing the special light observation, in the signal processing, the white balance at the time of the normal light observation does not always provide the color tone suitable for the observation.

Conventionally, even if the xenon lamp, which is the normal light of the light source device, is burnt out and switched to the halogen lamp, which is an emergency light, the signal processing operation of the processor has not been changed. For this reason, when switching to an emergency light during the examination, the color suddenly changes, which makes observation difficult and makes the examination difficult.

For example, the emergency light lamp has a light quantity smaller than that of a normal xenon lamp for medical examination, and the observed image becomes dark when the emergency light is used.

Alternatively, even though the lamp which is turned on is a halogen lamp, the processing is carried out with the white balance set by the xenon lamp. Therefore, the obtained image was a reddish image.

As described above, since an accurate examination cannot be performed under an emergency light, usually only the removal of the endoscope is performed to ensure the safety of the patient.

Further, it is necessary to take measures to obtain a better image not only for the life and failure of the lamp but also for the decrease of the light quantity of the lamp due to aging. For example, the light amount of the xenon lamp used in the light source device is inversely proportional to the lighting time. For this reason, the light amount of the light source is twice or more different before and after the replacement of the lamp.

Conventionally, the loop characteristic of automatic dimming of illumination light is as follows:
Since the lamp was set for several tens of hours of lighting, the dimming loop gain is set low and the response becomes slow immediately before replacement of a new product due to insufficient light intensity. On the other hand, immediately after the replacement, on the contrary, the light control loop gain was increased due to the excessive light amount, and the hunting was likely to occur.

Further, when performing the light control operation, the color of the illumination light changes depending on the relationship between the diaphragm blades and the optical path, that is, the diaphragm (diaphragm position), so that the color tone changes.

Alternatively, there is the following problem due to the relationship between the decrease in the lamp light quantity and the AGC (auto gain control) in the processor.

The processor of an electronic endoscopic device is generally
AGC to keep the level of the signal picked up by CCD constant
It is carried out. However, when the lamp light intensity decreases,
When the AGC operates, noise becomes noticeable. In particular, when the normal light is switched to the emergency light, the abnormal color tone becomes noticeable.

Regarding the operation of the AGC, there is a problem due to the relation with the diaphragm as the light quantity adjusting means of the light source.

For displaying the endoscopic image, there is a device for simultaneously displaying a parent screen and a child screen. This device normally displays a moving image only on the main screen. However, when displaying a still image, it is more convenient for the observer to display a moving image at the same time. Therefore, a device has been proposed in which one displays a moving image and the other displays a still image.

In the above apparatus, when the CCD shutter mode is used for freezing, the iris (blades) of the diaphragm provided in the light source device works so that the CCD has an appropriate exposure amount, and the diaphragm is opened. However, when the observation distance is long and proper brightness cannot be obtained, flash irradiation is performed during freeze.
At this time, for example, when the child screen is displaying a moving image, the AGC reacts to the flash irradiation, and an unsightly image such as hunting is displayed.

AGC is based on the reflected light from the subject,
Although it works to keep the signal level constant, it has the above-mentioned drawbacks depending on the state of the diaphragm and the illumination light source, and the conventional ones have been individually addressed such as the state of the light source device and multiple illumination modes. There wasn't.

In addition to this, in the conventional electronic endoscope apparatus, when a light source having no light quantity adjusting means is connected instead of the light source having a function capable of automatic light control, the light quantity can be appropriately controlled. It was not possible to obtain a normal image.

Further, in the conventional electronic endoscope apparatus, when transillumination is performed in the light source, the diaphragm is opened, the amount of light cannot be controlled, and the brightness of the image is saturated.

As described above, depending on the illumination light generating means information such as the type of light source, the operating state, and the function, if various measures are not taken, problems such as deterioration of image quality and efficiency will occur.

An object of the present invention is to provide an electronic endoscope apparatus capable of changing the optimum signal processing operation of an image pickup signal in accordance with the information regarding the illumination light generating means.

[0042]

The electronic endoscope apparatus according to the present invention is obtained by illuminating light generating means for generating illuminating light for illuminating an object and an object image illuminated by the illuminating light. A signal processing means for signal-processing an image pickup signal, an information supplying means for supplying illumination light generating means information on the illumination light generating means, and a signal processing means for supplying the illumination light generating means based on the illumination light generating means information supplied by the information supplying means. Signal processing operation changing means for changing the signal processing operation.

[0043]

In the configuration of the present invention, the signal processing operation changing means changes the signal processing operation of the signal processing means based on the illumination light generating means information supplied from the information supplying means. The signal processing means performs an appropriate signal processing operation according to the illumination light generating means information.

[0044]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 3 shows a configuration example of the electronic endoscope apparatus of the first embodiment. The electronic endoscope device 1 shown in FIG. 3 includes an electronic endoscope 2, a light source device 3 as illumination light generation means, a processor 4 as signal processing means, and a monitor (not shown).

The electronic endoscope 2 has an elongated and flexible insertion portion 5, for example, and a large-diameter operating portion 6 is connected to the rear end of the insertion portion 5. The operation portion has a flexible cable 7 extending laterally, and a connector 8 is provided at a tip portion of the cable 7.
Is provided. The electronic endoscope 2 is connected to the light source device 3. In addition, the electronic endoscope 2 is
The video signal processing circuit 9 is connected to the built-in processor 4. The endoscope and the cable shown in FIG. 3 schematically show this state.

Further, the monitor is connected to the video signal processing circuit 9 of the processor.
Further, an image recording device can be connected to the video signal processing circuit 9.

On the distal end side of the insertion portion 5, a hard distal end portion 10 and a bendable bending portion (not shown) adjacent to the rear end of the distal end portion 10 are provided. Further, the endoscope 2 is configured such that the bending portion can be bent in the left-right direction or the up-down direction by rotating a bending operation portion knob (not shown) provided in the operation portion 6.

As shown in FIG. 3, a light guide 11 for transmitting illumination light is inserted into the insertion portion 5 of the electronic endoscope 2. The incident end of the light guide 11 is connected to the light source device 3, and the tip surface of the light guide 11 is arranged at the tip portion 10 of the insertion portion 5 so that the illumination light can be emitted from the tip portion 10. It has become.

An objective lens system 12 is provided at the tip portion 10, and the objective lens system 12 has an image forming position at the image forming position.
A solid-state image sensor 13 is provided. The solid-state imaging device 13 has sensitivity in a wide wavelength range including the visible range and the ultraviolet range to the infrared range. Signal lines 14 and 15 are connected to the solid-state imaging device 13, and the signal lines 14 and 15 are connected to the solid-state image pickup device 13.
Reference numeral 15 is inserted through the insertion portion 5 and the cable 7 and is connected to the connector 8.

On the other hand, in the light source device 3, there is provided a lamp 16 which constitutes an illuminating means for emitting light in a wide band from ultraviolet light to infrared light. As the lamp 16, for example, a general xenon lamp or a strobe lamp,
A halogen lamp or the like can be used. The xenon lamp, strobe lamp, and halogen lamp emit a large amount of not only visible light but also ultraviolet light and infrared light. Lamp 16
The type can be selected according to the application.

In the light source device 3, there is a discrimination signal generator 18 as an information supply means for generating different light source discrimination signals according to the type of the lamp 16 and the illumination (imaging) system, for example, the simultaneous system. ing. This discrimination signal generator 18
For example, an optical sensor (not shown) is arranged in the vicinity of the lamp 16, and a light source discrimination signal corresponding to the type of the light source is generated based on the signal photoelectrically converted by the optical sensor.

The discrimination signal generator 18 may be set according to the type of the lamp or the like, or may be set in advance so that a predetermined light source discrimination signal is generated for each light source device 3. good.

Electric power is supplied to the lamp 16 by a power supply unit (not shown). The light emitted from the lamp 16 is incident on the incident end of the light guide 11, is guided to the tip portion 10 via the light guide 11, is emitted from the tip portion 10, and illuminates an observation site. Has become.

The return light from the observation site due to the illumination light is imaged on the solid-state image pickup device 13 by the objective lens system 12 and photoelectrically converted. A drive pulse from a drive circuit 17 in the processor 4 is applied to the solid-state image sensor 13 via the signal line 14,
Reading and transfer are performed by this drive pulse. The video signal read from the solid-state image sensor 13 is input to the video signal processing circuit 9 via the signal line 15. The video signal processing circuit 9 amplifies the video signal, performs signal processing such as γ correction and white balance, and outputs it as R, G, B color signals or NTSC composite signal.

Here, the white balance operation is, for example,
The values of the output RGB signals are controlled to be the same when a white subject is imaged.

The R, G, B color signals or N
A TSC composite signal is input to the color monitor, and the color monitor displays the observed region in color.

In the processor 4, according to the light source discrimination signal output from the discrimination signal generator 18 of the light source device 3,
It has a discrimination circuit 19 as a signal processing operation changing means for switching an operation of signal processing described later. Between the discrimination signal generator 3 and the discrimination circuit 19 which constitute the discrimination instruction means,
It is connected by a signal line 20.

The video signal processing circuit 9 includes a discrimination circuit 19
The switching signal of (1) appropriately switches the processing operation of the video signal according to the type of the light source.

With the above structure, the light emitted from the lamp 16 in the light source device 3 passes through the light guide 11 and passes through the tip portion 10.
It is irradiated toward the observation site from. Light guide 11
The observation site illuminated by is imaged on the solid-state imaging device 13 by the objective lens system 12. Solid-state image sensor 1
The image (light) of the observed region formed in 3 is photoelectrically converted, and is read at a predetermined timing by the drive pulse transmitted by the drive circuit 17 through the signal line 14. The photoelectrically converted video signal is input to the video signal processing circuit 9 through the signal line 15.

On the other hand, in the light source device 3, the discrimination signal generator 1
8, a light source discrimination signal corresponding to the type of light source is generated. This light source discrimination signal is input to the discrimination circuit 19 in the processor 4 through the signal line 20. In the discrimination circuit 19,
The type of the light source is discriminated and the information is input to the video signal processing circuit 9 as a switching signal. In the video signal processing circuit 9, the signal processing operation is switched according to the switching signal of the discrimination circuit 19 to perform optimum video signal processing.

Next, a configuration example relating to the transmission of the light source discriminating signal will be described with reference to FIG. 4 and the state of the signal waveform will be described with reference to FIG. In the configuration example shown in FIG. 4, in a device having an automatic light source dimming means, a dimming signal line 21 connecting the processor 4 and the light source device 3 is shared as the signal line 20 for transmitting a light source discrimination signal. is there.

In the light source device 3, the discrimination signal generator 18 converts the light source information into a frequency signal.
The discrimination signal generator 18 applies so-called frequency modulation. An example of this light source discrimination frequency signal is shown in FIG. 5A, and this light source discrimination frequency signal represents the type of light source by the fundamental frequency.

The light source discrimination frequency signal is superimposed on the dimming signal, which will be described later, on the dimming signal line 21 by the light source side superimposing circuit 22. FIG. 5B shows these signals.

The light source discrimination frequency signal transmitted through the dimming signal line 21 of the endoscope 2 is separated from the dimming signal by the superposing circuit 23 on the processor side, and the light source discrimination shown in FIG. Frequency signal. The discrimination circuit 19 to which the light source discrimination frequency signal is input discriminates the type of the light source from the frequency component and outputs the result to the video signal processing circuit 9 as a switching signal.

On the other hand, the dimming signal is generated by the dimming signal detection circuit 24 inside the processor 4. The dimming signal detection circuit 24 detects the output of the solid-state image sensor 13 and generates a dimming signal. This dimming signal is supplied to the processor-side superposition circuit 23, the dimming signal line 21, and the light source-side superposition circuit 2.
The light is input to the dimming circuit 25 inside the light source device 3 through the line 2. As shown in FIG. 5B, since the dimming signal is a DC signal, it is easy to separate and combine the AC component with the light source discrimination frequency signal. Note that Vref shown in FIG. 5B indicates the reference level of the dimming signal.

The dimming circuit 25 automatically controls the brightness of the lamp 16 according to the dimming signal.

As described above, the light source discrimination frequency signal can be transmitted using the dimming signal line 21 and the superposing circuits 22 and 23.

In the example of the configuration shown in FIG. 4, it is explained that it is combined with the dimming signal, but it is also possible to provide a dedicated transmission line for the discrimination signal to transmit the discrimination signal. Further, in the case of using a dedicated line, the discrimination signal can be a code signal or a DC signal instead of the frequency signal.

Next, an example of the video signal processing circuit 9 will be described with reference to FIG. The video signal input to the video signal processing circuit 9 is input to the preprocessing circuit 26. In this preprocessing circuit 26, field sequential processing or simultaneous processing is performed depending on the illumination system.

Switching of the processing of the preprocessing circuit 26 is performed by
This is performed by the switching signal of the discrimination circuit 19. This switching signal is generated according to the type of the light source, and includes the information of the color plane sequential light source or the simultaneous light source, and operates as a signal for instructing proper switching. The switching signal also switches the method of generating the light source dimming signal.

The preprocessing circuit 26 outputs R, G, B color signals to the white balance circuit 27. In the white balance circuit 27, for example, when capturing a white image,
The RGB color signals are controlled so that their levels match. This operation is normally performed by imaging white and detecting the level of the output video signal. However, this circuit 2
In No. 7, the operation is changed depending on the type of the light source when performing the preset operation or when optimizing the initial value. The switching of this operation is controlled by the switching signal according to the type of the light source.

Next, the R, G and B color signals output from the white balance circuit 23 are input to the matrix circuit 28. In the matrix circuit 28, matrix calculation is performed by the following equation in order to improve color reproduction.

[0073]

[Formula 1] A is a 3 × 3 matrix. The input RGB color signals are converted into R′G′B ′ color signals by the matrix A.

In order to achieve optimum color reproduction, it is necessary to switch the matrix A depending on the type of lamp and the illumination method (frame sequential, simultaneous, etc.). Therefore, the matrix circuit 28 changes the setting of the matrix A according to the switching signal.

As described above, in the present embodiment, the optimum video signal is controlled by controlling the processing operation of the video signal processing circuit 9 by the (different) switching signal generated according to the type of lamp and the lighting system. It is possible to prevent the deterioration of image quality. In other words, the present embodiment can improve the image quality that would otherwise deteriorate unless the processing operation is changed.

The control of the video signal processing by the switching signal can be applied not only to the above-mentioned ones but also to all the factors that change depending on the kind of the light source, such as the driving method of the solid-state image pickup device and the control of the memory. .

7 to 9 relate to the second embodiment of the present invention. FIG. 7 is an overall configuration diagram of an electronic endoscope apparatus, FIG. 8 is a block diagram of a white balance circuit, and FIG. FIG. 6 is a block diagram of another white balance circuit.

The second embodiment differs from the first embodiment shown in FIG. 3 in that a discrimination circuit 29 for discriminating the kind of the light source from the output signal of the video signal processing circuit 9 is excluded except for the discrimination signal generator 18. Have The video signal processing circuit 9 has a post-processing circuit 30 in place of the matrix circuit 28 shown in FIG. Other configurations and operations similar to those of the first embodiment are designated by the same reference numerals and description thereof will be omitted. Only the points different from the first embodiment will be described below.

The operation until the video signal is input from the solid-state image pickup device 13 to the processor 4 is the same as in the first embodiment. This video signal is subjected to predetermined processing such as color separation and synchronization by the preprocessing circuit 26 of the video signal processing circuit 9,
Input to the white balance circuit 27. In the white balance circuit 27, for example, when capturing a white image, the levels of the RGB color signals are controlled to match. For this level adjustment, the white balance circuit 27 uses the output signal of the preprocessing circuit 26 to create a control signal. A configuration example of this control is shown in FIGS. 8 and 9.

The white balance circuit shown in FIG. 8 has a gain control amplifier (GCA) 31R,
The comparison circuits 3R and 32B compare the levels of the R and B signals output from 31B and the input G signal, and the comparison circuit 3
The gain control amplifier 31 adjusts the RGB signal levels according to the control signals output from the 2R and 32B.
The R and 31B gains are adjusted. This control signal is also output to the discrimination circuit 29.

In the white balance circuit shown in FIG. 9, the R and B signals output from the gain control amplifiers 31R and 31B are changed to the input G signal due to the difference in level between the input R and B signals and the input G signal during white image pickup. The control signal generation circuits 33R and 33B generate control signals so as to match the levels of the above, and output the control signals to the gain control amplifiers 31R and 31B. This control signal is also output to the discrimination circuit 29.

The control signal for white balance varies depending on the type of light source. For example, considering the case of a xenon lamp as a reference, when the lamp is changed to a halogen, the color temperature of the light source becomes high and the energy of the long wavelength component of light becomes large. Therefore, the white balance circuit 2
The R signal input to 7 is larger and the B signal is smaller. Therefore, the gain control amplifiers 31R, 3R
The control signal input to 1B is smaller for the R signal and larger for the B signal than when the xenon lamp is used. The determination circuit 29 inputs this control signal, determines the type of the light source, and outputs the result to the post-processing circuit 30 as a switching signal.

With this switching signal, the post-processing circuit 30 switches the value of the matrix constant and the like, as in the first embodiment.

As described above, in the second embodiment, the light source type is discriminated by the control signal for white balance, and the video signal processing is switched according to the result. Therefore, in the present embodiment, it is not necessary to transmit the discrimination signal from the light source, and the system can be simplified as compared with the first embodiment.

Further, in the above description, the processing of the post-processing circuit 30 is simply switched by the switching signal, but the operation of the pre-processing circuit 26 which is not involved in the light source determination may be switched. it can.

FIG. 10 is an overall configuration diagram of an electronic endoscope apparatus according to the third embodiment of the present invention.

In the third embodiment, instead of the discrimination signal generator 18 of the first embodiment shown in FIG. 3, an optical sensor arranged at the branch end of the light guide 11 is provided, and this optical sensor and the discrimination circuit are used. It is configured to determine the type of light source. Other configurations and operations similar to those of the first embodiment are designated by the same reference numerals and description thereof will be omitted.

In the third embodiment, the operation in which the video signal is read from the solid-state image sensor 13 and processed by the processor 4 is the same as that in the first embodiment.

As shown in FIG. 10, the light guide 11
Is bifurcated from the entrance end toward the exit end. The light guide 11 guides the light emitted from the light source to one emission end of the tip portion 10, and also extracts a part of the light from the light source from the end face of the branch portion 11a. A sensor 35 for detecting the emitted light is arranged near the end of the branch portion 11a. The sensor 35 senses the color temperature and the spectrum energy distribution of the light sent from the light source. This sensing data is discriminated by the discriminating circuit 19A of the processor 4, and the result is output to the video signal processing circuit 9 as a switching signal. The operation of the video signal control circuit 9 based on this switching signal is the same as that of the first embodiment, and the description thereof is omitted.

The sensor 35 may use the light branched from any part of the light guide 11, and may be arranged at any part as long as the light emitted from the light source is emitted.

In each of the above embodiments, the white balance and the signal processing have been described by using the RGB signals. However, in the case of using the luminance (Y) and color difference (RY, BY, etc.) signals. Can also be applied. Although not shown, in the case of the frame sequential method, the lamp 16 of the light source device 3 irradiates a plurality of illumination lights having different wavelength ranges in time series. This is realized by interposing a rotary filter between the incident end of the light guide 11 and the lamp 16.

11 and 12 relate to a fourth embodiment of the present invention, and FIG. 11 is an overall configuration diagram of an electronic endoscope apparatus, FIG.
2 is a block diagram showing a configuration example of a video signal processing circuit.

In this embodiment, the light source device 3 of the first embodiment is
A diaphragm 34 for adjusting the amount of illumination light of the lamp 16 is arranged. The diaphragm 34 controls the amount of light entering the light guide 11 from the lamp 16 so that an optimum video signal level can be obtained. At this time, the color of the light emitted from the light guide 11 may change depending on the shape of the diaphragm and the positional relationship between the diaphragm and the optical axis. This is mainly because the diffraction effect of light becomes large especially when the diaphragm amount is large.

In this embodiment, in order to improve the color reproducibility of the subject in the above situation, the aperture position and the like are detected and the processing of the video signal is changed. Therefore, the light source device 3 is provided with a diaphragm position detector 36 that detects the diaphragm position from the diaphragm 34, that is, the diaphragm amount. Then, the detection signal of the diaphragm position detector 36 is supplied to the discrimination signal generator 18. The discrimination signal of the discrimination signal generator 18 is output to the discrimination circuit 19 of the processor 4. Other than that, the same components as those in the first embodiment are designated by the same reference numerals and the description thereof will be omitted.

With the above construction, the light source device 3 is normally illuminated by the main lamp 16. The light of the main lamp 16 passes through the light guide 11 and is emitted to the subject from the tip of the endoscope. The subject image is formed on the solid-state image sensor 13 by the objective lens 12, converted into an electric signal by the solid-state image sensor 13, transmitted to the processor 4, and processed by the video signal processing circuit 9.

The diaphragm position of the diaphragm 34 is detected by the diaphragm position detector 36 and sent to the discrimination signal generator 18. The discrimination signal generator 18 previously stores, for example, color change information with respect to the diaphragm position of the diaphragm 34, and a discrimination signal corresponding to the color change information is stored in the discrimination signal generator 18.
Will be output. Discrimination circuit 19 on the processor 4 side
Thus, the signal from the discrimination signal generator 18 is converted into a color conversion signal and transmitted to the video signal processing circuit 9.

FIG. 12 shows a configuration example of the video signal processing circuit 9. The video signal processing circuit 9 includes a discrimination circuit 19
Is received by the coefficient generator 37, and a matrix constant corresponding to the color conversion signal output from the discrimination circuit 19 is generated,
The color conversion setting of the matrix circuit 38 as the color conversion means is changed, and the color of the output image changes so as to match the aperture position.

In this embodiment, it is possible to always obtain an image with normal color reproduction regardless of the change of the color of the emitted (illumination) light by the diaphragm.

In this embodiment, the color conversion means is a matrix circuit, but other color conversion means, for example, classification A7-159.
A color space shown in 3, A7-1594 may be used for conversion. Further, the color conversion means is an LCA.
A programmable element such as the above may be used to perform reprogramming in accordance with an instruction from the determination circuit 19.

13 to 17 relate to the fifth embodiment of the present invention. FIG. 13 is an overall configuration diagram of an electronic endoscope apparatus, FIG. 14 is a configuration diagram of a rotary filter, and FIG. 15 is a video signal processing circuit. 16 is a block diagram showing an example of the configuration of FIG. 16, FIG. 16 is an explanatory diagram of chromaticity conversion, and FIG. 17 is a flowchart relating to change / setting of matrix coefficients.

The light source device 3 of the present embodiment is constructed so as to emit the frame-sequential illumination light, and the rotary filter 40 rotated by the motor 39 is arranged on the optical path of the illumination light. That is, between the lamp 16 and the light guide 11, for example, R (red), G (green), B as shown in FIG.
A rotary filter 40 for color separation, in which (blue) filters are arranged, is inserted. Processor 4 shown in FIG.
Is configured to obtain a correction signal for the rotation filter from the light source device 3 from the discrimination signal generator 18 and change the operation of the color conversion means of the video signal processing circuit 9 according to the correction signal. Other configurations and operations similar to those of the first embodiment are designated by the same reference numerals and description thereof will be omitted.

In the above arrangement, the light source device 3 is normally illuminated by the main lamp 16. The rotary filter 40 is rotated by a motor 39, and the illumination light is synchronized with the signal read cycle of the solid-state image sensor, and the R, G, and B are synchronized.
A signal corresponding to the filter is incident on the light guide 11. The light decomposed into a plurality of wavelength bandwidths by each filter passes through the light guide 11 and is radiated to the subject in time series from the tip of the endoscope. The subject image is formed on the solid-state imaging device 13 by the objective lens 12. Solid-state image sensor 13
From, the electric signals corresponding to the respective color filters are output in time series, are synchronized by the video signal processing circuit 9 of the processor 4, are color processed, and are output.

Here, the rotary filter 40 has R, G, B
The spectral characteristics of each filter differ depending on the filter. Therefore, when the filters are different, the electric signals for the respective colors output from the solid-state image sensor 13 also differ, resulting in different color reproducibility of the video signal.

Since the filter is different for each light source, the operation of the color conversion means of the video signal processing circuit 9 is switched according to the light source in this embodiment. FIG. 15 shows a configuration example of the color conversion means in the video signal processing circuit 9. This processing circuit 9
Has a coefficient generator 41 and a matrix circuit 42.

Further, the discrimination signal generator 18 of the light source device 3 stores in advance data for changing the signal processing setting in the processor 4 in accordance with the spectral characteristic of the rotary filter 40 and the like.

The operation will be described below with reference to the flow chart shown in FIG. First, when the light source device 3 and the processor 4 are electrically connected, in steps S41 and S42,
Data corresponding to the rotary filter 40 inside the light source is transmitted from the discrimination signal generator 18 inside the light source to the processor 4. In step S43, the discrimination circuit 19 of the processor 4
The discriminating circuit 19 discriminates the transmitted data.

In steps S44 to S46, the coefficient generator 41 of the video signal processing circuit 9 selects and generates the matrix coefficient corresponding to the rotary filter 40 to be used in accordance with the judgment signal of the judgment circuit 19. The matrix circuit 46 is loaded. As a result, the operation of the matrix circuit 42 is changed.

The method of changing the matrix coefficient will be described below.

The color important for color reproduction of the endoscope is generally a red color. For example, if you take a reference image of red,
It is assumed that the position of the color signal corresponding to the red on the vectorscope must be the position A in FIG.

Here, as described above, due to the dispersion of the spectral characteristics of the rotary filter 40 of the light source device, even if the white balance is adjusted, the position on the vectorscope corresponding to the reference red is the specified A position. I won't. It is assumed that the position of the color signal on the vector scope is, for example, the position B in FIG. In this case, in the matrix circuit 42, a matrix constant for converting the saturation and hue of the signal corresponding to the reference red is set, and the conversion is performed so that the position becomes A on the vector scope.

In the above description, the description has been made only for the reddish color, one color, but in reality, a plurality of colors are considered, and the matrix constants are determined so as to achieve the optimum color reproduction as a whole.

The matrix circuit 42 can easily change the constants by using an SRAM or the like.

In this embodiment, even if the rotary filter of the light source device is different, the color reproducibility can be maintained without causing the color change.

In this embodiment, the color conversion means is a matrix circuit, but other color conversion means, for example, classification A7-159.
The color space shown in A3-1594 may be converted. Further, the color conversion means may be configured to reprogram according to an instruction from the discrimination circuit 19 using a programmable element such as LCA.

18 to 22 relate to the sixth embodiment of the present invention, FIG. 18 is an overall block diagram of an electronic endoscope apparatus, and FIG. 19 is a block diagram showing a block diagram of a video signal processing circuit. 20 is an explanatory diagram of chromaticity conversion, FIG. 21 is a characteristic diagram of a normal light and an emergency light, and FIG.

The light source device according to the present embodiment is configured to switch to the emergency light when the normal light is cut off. Therefore,
When the light source is switched to the emergency light, the processing of the processor, for example, the operation of the color conversion means is changed so as to be suitable for the light amount and the spectral characteristic of the emergency light.

In this embodiment, as the main lamp 16 which is the ordinary lamp of the light source device 3 shown in FIG. 18, for example, a xenon lamp is used. If the main lamp 16 cannot be lit during inspection for some reason, the lamp control circuit 43 illuminates it with the emergency light 44. For this emergency light 44, for example, a halogen lamp is used.

The lamp control circuit 43 notifies the discrimination signal generator 18 of whether or not the lamp used is switched to the emergency light. The discrimination circuit 19 of the processor 4 shown in FIG. 18 switches the processing operation of the video signal processing circuit 9 according to the discrimination signal of the discrimination signal generator 18. Other configurations and operations similar to those of the first embodiment are designated by the same reference numerals and description thereof will be omitted.

With the above structure, the light source device 3 is normally illuminated by the main lamp 16. The illumination light of the main lamp 16 passes through the light guide 11 and is emitted to the subject from the tip of the endoscope. The subject image is formed on the solid-state image sensor 13 by the objective lens 12, converted into an electric signal by the solid-state image sensor 13, and transmitted to the processor 4.
It is processed by the video signal processing circuit 9.

The operation will be described below with reference to the flow chart shown in FIG.

If the main lamp 16 cannot be lit during the inspection for some reason, step S51.
Then, the emergency light 4 is switched by the lamp controller 43.
Illumination is done by 4. Since a halogen lamp is used as the emergency light 44, as shown in FIG. 21, the emergency light 44 has a lower color temperature than the xenon lamp. In this case, when the video signal is processed by the video signal processing circuit 9 set up for the xenon lamp having a high color temperature, the color becomes different from the actual color, and proper inspection cannot be continued.

Therefore, the lamp controller 43 switches from the main lamp 16 to the emergency light 44, and at the same time as step S5.
In step 2, the discrimination signal generator 18 is notified that the lamp has been switched. In step S53, the discrimination signal generator 18
Sends a determination signal to the processor 4 notifying that it has switched to an emergency light. In steps S54 and S55, the discrimination circuit 19 on the processor 4 side recognizes that the lamp has been switched, and in step S56 and subsequent steps, the processing content of the video signal processing circuit 9 is changed.

FIG. 2 shows a structural example of the color conversion means of the video signal processing circuit 9. When the discriminator circuit 19 transmits the lamp switching signal, the video signal processing circuit 9 causes the coefficient generator 45 to send a matrix coefficient suitable for the switched emergency light to the matrix circuit 46.

Next, a method of changing the matrix constant will be described.

The red color is important for the color reproduction of the endoscopic image. For example, when a reference red image is captured, the position of the color signal corresponding to that red on the vectorscope is shown in FIG.
Suppose it must be in the 0 D position.

Here, as shown in FIG. 21, the emission characteristics of the xenon lamp and the halogen lamp are different. Therefore, even if the white balance is adjusted, it is assumed that the position on the vector scope corresponding to the reference red does not become the specified D position but the position C in the drawing, for example. In this case, the matrix circuit 46 uses steps S56 to S5.
As shown in 8, the matrix coefficient for converting the saturation and hue of the signal corresponding to the reference red is selected and set, and after the coefficient at the position of D on the vector scope is loaded, the signal is converted.

The matrix circuit 46 can easily change the coefficient by using an SRAM or the like.

In the above description, the description has been made only for a reddish color, one color, but in reality, a plurality of colors are considered, and the matrix constants are determined so as to achieve the optimum color reproduction as a whole.

In the present embodiment, the color conversion circuit is a matrix circuit, but other color conversion means, for example, classification A7-159.
A color space as shown in A3-1594 may be used. Further, the color conversion means is LC
A programmable element such as A may be used to perform reprogramming according to an instruction from the determination circuit 19.

In this embodiment, even when the light source is switched from the normal light to the emergency light, the change of the image, especially the color change can be reduced.

23 to 26 relate to the seventh embodiment of the present invention, FIG. 23 is an overall block diagram of an electronic endoscope apparatus, and FIG. 24 is a block diagram showing a configuration example of a video signal processing circuit. 25 is a block diagram showing another configuration example of the video signal processing circuit, and FIG. 26 is a block diagram showing another configuration example of the video signal processing circuit.

In this embodiment, the light source device 3 of the first embodiment is
A diaphragm 47 for adjusting the amount of illumination light of the lamp 16 is arranged. The diaphragm 47 controls the amount of light entering the light guide 11 from the lamp 16 so that an optimum video signal level can be obtained.

In the present embodiment, the distance between the subject and the tip of the endoscope is detected from the diaphragm position information of the diaphragm 47, and the color signal processing means of the video signal processing circuit 9 detects the distance according to the detection result. It is configured to change its behavior.

As shown in FIG. 23, the diaphragm position of the diaphragm 47 is detected by the diaphragm position detector 48 and sent to the discrimination signal generator 18. Discrimination signal generator 1
The color change information for the diaphragm position 8 is stored in advance, for example, and the discrimination signal generator 18 outputs a discrimination signal corresponding to the color change information. On the processor 4 side, the discrimination circuit 19 converts the signal from the discrimination signal generator 18 into a color conversion signal and transmits it to the video signal processing circuit 9. Other configurations and operations similar to those of the first embodiment are designated by the same reference numerals and description thereof will be omitted.

With the above structure, the light source device 3 is normally illuminated by the main lamp 16. Main lamp 16
The illumination light of (1) passes through the light guide 11 and is emitted to the subject from the tip of the endoscope. The subject image is formed on the solid-state image sensor 13 by the objective lens 12, converted into an electric signal by the solid-state image sensor 13, transmitted to the processor 4, and processed by the video signal processing circuit 9.

On the other hand, the diaphragm position of the diaphragm 47 is detected by the diaphragm position detector 48 and sent to the discrimination signal generator 18. The discrimination signal generator 18 outputs a discrimination signal of color change corresponding to the diaphragm position of the diaphragm 47. On the side of the processor 4 which has received the discrimination signal, the discrimination circuit 19 converts the signal from the discrimination signal generator 18 into a color conversion signal and transmits it to the video signal processing circuit 9.

A color correction circuit 53 is provided in the video signal processing circuit 9.
Are arranged, and color correction is performed according to the output signal of the discrimination circuit 19.

FIG. 2 shows a first configuration example of the color correction circuit 53. For example, the RGB signal input to the color correction circuit 53 is converted into Y, RY and BY signals by the matrix circuit 49, and the coefficients are multiplied by the coefficient multipliers 50a and 50b so that the signal size is converted. It has become.

On the other hand, the discrimination circuit 19 discriminates the distance from the subject and inputs the discrimination signal to the far point discrimination circuit 51. In the far point discrimination circuit 51,
According to the discrimination result of the discrimination signal generator 19, the coefficient unit 50
The coefficients a and 50b are set.

In the case of an electronic endoscope, observation is performed by irradiating the subject with light from the emission end of the light guide 11 at the tip of the endoscope. Therefore, when the distal end portion of the endoscope is close to the subject, the captured image becomes bright, so the dimming circuit (not shown) adjusts the diaphragm 47 to control the light emitted from the light source. On the contrary, when the distal end portion of the endoscope is farther than the subject, the image becomes dark, and therefore, the light control is performed so as to increase the amount of light emitted from the light source (open the diaphragm of the light source). Therefore, by using the aperture position information detected by the aperture position detector 48, the distance between the subject and the tip can be detected. The detection of the diaphragm position may use a dimming control signal output from the dimming circuit to the diaphragm 47.

On the basis of the diaphragm position information, the far point discriminating circuit 51 detects the distance to the subject and discriminates whether or not the subject is at the far point, and the far point discriminating circuit 51 causes the coefficient unit 50.
A control signal is output to a and 50b, and coefficient multipliers 50a and 5b
A coefficient of 0b is set.

Here, the larger the distance between the subject and the distal end portion of the endoscope, the greater the influence of the secondary reflected light by the internal organ wall, and the effect of the color of the internal organ wall surface, the darker the subject color. Therefore, in the present embodiment, the larger the distance between the subject and the tip of the endoscope, the smaller the color difference signals R-Y and B-Y are controlled by the coefficient units 50a and 50b. This control is linearly or non-linearly adaptively performed depending on the size of the aperture position information. As a result, the saturation is corrected in the case of far point observation.

Then, the luminance signal Y and the coefficient unit 50a,
The color difference signals R-Y and B-Y output from 50b are converted again into RGB signals by the inverse matrix circuit 52. This RGB signal is output as an output signal of the color correction circuit 53.

As described above, in this embodiment, the color correction circuit 5
By performing the color correction in 3, it is possible to reduce the influence of the secondary reflected light due to the internal wall when observing a far point, and it is possible to always correct the color level optimally regardless of the distance.

FIG. 25 shows a second configuration example of the correction circuit 53A.

The second configuration example is an example in which, in addition to the components of the first configuration example, a detector is provided on each line of the Y, RY, and BY signals.

The RGB signals input to the color correction circuit 53A shown in FIG.
The signals are converted into Y and BY signals, and the size is converted by the coefficient units 50a and 50b. Further, similarly to the first configuration example, the discrimination signal according to the diaphragm position from the discrimination signal generator 19 is input to the far point discrimination circuit 51.

Further, the Y signal and the coefficient units 50a and 50b
The RY and BY signals output from the
The magnitude is detected (for example, an average value is calculated) by a, 54b, and 54c, and is input to the far point determination circuit 51.

The far point discriminating circuit 51 detects the distance between the subject and the endoscope front end based on the output signal of the discriminating circuit 19 corresponding to the diaphragm position signal as described in the first configuration example.

Here, when the distance between the subject and the tip is small, the influence of the secondary reflected light is small and the color balance is not lost. Therefore, in the far point discriminating circuit 51, when the subject and the tip portion are close to each other by a predetermined distance, the detector 5
The output values of 4a, 54b and 54c are held. Then, even when the distance between the subject and the tip portion becomes large, the coefficient unit 50 is adjusted so that the ratio of the detectors 54a, 54b, 54c becomes the same as the ratio of the held detector outputs.
By controlling in this way, Y, RY, BY are controlled regardless of the distance to the subject.
Since the signal ratio is maintained in the same manner as when the distance between the subject and the tip is short, the influence of the secondary reflected light is small. Therefore, the color level can always be optimally corrected regardless of the distance.

Then, the luminance signal Y and the coefficient units 50a, 5
The color difference signals RY and BY output from 0b are converted into RGB signals by the inverse matrix circuit 52 and output as output signals of the color correction circuit 53A.

In the first and second configuration examples of the color correction circuit described above, the RGB signal is generated from the Y, RY and BY signals in the inverse matrix circuit 52. The circuit 49 may convert into G, RY, and BY signals, and the inverse matrix circuit 52 may synthesize RGB signals from the G, RY, and BY signals.

FIG. 26 shows a third configuration example of the color correction circuit 53B.

The third structural example is an example in which the matrix circuit is not provided. R input to the color correction circuit 53B
Of the GB signals, the R and B signals are input to the coefficient multipliers 50c and 50d and their magnitudes are converted. Further, similarly to the first configuration example, the output signal of the discriminating circuit 19 is input to the far point discriminating circuit 51. The G signal and the R and B signals output from the coefficient units 50c and 50d are detected by the detectors 54a, 54b, and 54c in magnitude (for example, average value calculation) and input to the far point determination circuit 51A. To do.

The far point discriminating circuit 51 detects the distance between the object and the tip of the endoscope based on the discrimination result of the diaphragm position as described in the first configuration example. Far point discrimination circuit 5
In No. 1, as in the second configuration example, when the subject and the tip end portion are close to each other by a certain predetermined distance, the detectors 54a and 54a
The output values of 4b and 54c are held. Then, even when the distance between the subject and the tip of the endoscope becomes large, the coefficient unit 50 is adjusted so that the ratio of the detectors 54a, 54b, 54c becomes the same as the ratio of the held detector outputs.
c, 50d are controlled.

By controlling in this way, the ratio of the G, R, B signals is maintained regardless of the distance to the subject, as in the case where the distance between the subject and the tip is short, so that
The influence of the secondary reflected light is reduced. Therefore, the color level can always be optimally corrected regardless of the distance.

In the case of the third configuration example, since the RGB signals can be processed as they are, there is no need for a matrix circuit such as a processing system for converting to the color difference signals, and the advantage is that the circuit configuration is simplified. Have. Furthermore, since the RGB signal ratio is controlled, it is possible to perform correction with higher accuracy than in a method that only controls saturation.

In the case of the third configuration example, R,
Although the magnitude of only the B signal is controlled, a coefficient multiplier may be inserted for the G signal to control the magnitudes of the three RGB signals.

In the second and third configuration examples, the signal level is controlled so as to have the same ratio as the ratio of each signal when the subject is at a short distance, but the signal level of each color is changed according to the distance. You may control so that a ratio may be changed.

27 and 28 relate to the eighth embodiment of the present invention, and FIG. 27 is an overall configuration diagram of the electronic endoscope apparatus of FIG.
FIG. 3 is a block diagram showing a configuration example of a video signal processing circuit.

The apparatus of this embodiment separates the reflected light from the subject returning from the distal end of the endoscope through the light guide on the light source side, detects the color of the subject, for example, the internal wall of the internal organs, and outputs the detection result as a secondary result. The configuration is such that color correction is performed as a reflected light component.

Other than that, the same components and operations as those of the seventh embodiment are designated by the same reference numerals and the description thereof will be omitted.

The illumination light of the main lamp 16 is generated by the diaphragm 47,
The light is passed through the beam splitter and the light guide 11, and the subject is irradiated from the tip of the endoscope. Object image is objective lens 1
An image is formed on the solid-state image sensor 13 by 2 and the solid-state image sensor 1
It is converted into an electric signal by 3 and transmitted to the processor 4. The electric signal is processed by the video signal processing circuit 9 of the processor 4. The diaphragm position of the diaphragm 47 is detected by the diaphragm position detector 48 and sent to the discrimination signal generator 18.

On the other hand, the light radiated from the tip of the endoscope is radiated to a subject or the like and reflected, and the reflected light returns to the light source device 3 through the light guide 11 again. This return light is separated by the beam splitter 55 and detected by the sensor 56.

The signal detected by the sensor 56 is
The detection circuit 57 detects the respective component ratios of R, G, and B and sends them to the discrimination signal generator 18. This detected signal is an average of the reflected lights of the light emitted from the light guide 11. Therefore, in the case of a medical endoscope, it can be said that it represents the color of the entire visceral wall.

The discrimination signal generator 18 shown in FIG. 27 synthesizes the diaphragm position information and the reflected light information, and transmits them to the processor 4. The processor 4 again separates the signal transmitted from the light source by the discrimination circuit 19 into diaphragm position information and reflected light information, and sends the information to the video signal processing circuit 9.

FIG. 28 is a block diagram showing a configuration example of the color correction circuit of the video signal processing circuit 9. The color correction circuit shown in FIG. 28 inputs the separated diaphragm position information to the distance determination circuit 58. The distance discriminating circuit 58 estimates the distance between the tip of the endoscope and the subject according to the diaphragm position. Using this distance information and the reflected light information returned from the light guide 11,
The controller 59 controls the GCA (gain control
The gain of the amplifier 60a and the GCA 60b is controlled.

The gain control method will be described below. If the RGB ratio of the reflected light information is R: G: B = r: g: b, the gains GR and G of the GCA 60a and GCA 60b are obtained.
B becomes GR = k (g / r) and GB = 1 (g / b), respectively.

K is a variable in the distance information atmosphere (r / g), and is a variable that approaches "1" when the distance increases, and l also becomes "b" in the distance information atmosphere (b / g) and "l" when the distance increases. It is a variable that approaches 1 ”. The rate of change according to the distances of k and l is determined by the characteristics of the target object region of interest and the conditions such as the endoscope.

That is, GR and GB are close to "1" when the distance is short (the influence of the secondary reflected light is small), and the correction amount is set to be small. When the distance is long (the influence of the secondary reflected light is great), the correction according to the reflected light information becomes large.

In this embodiment, the influence of the secondary reflected light from the subject can be reduced.

29 to 34 relate to the ninth embodiment of the present invention, FIG. 29 is an overall configuration diagram of an electronic endoscope apparatus, and FIG. 30 is a first detection circuit corresponding to a frame sequential imaging system. Circuit diagram, FIG. 31 is a circuit diagram of a second detection circuit compatible with the simultaneous system, FIG. 32 is a circuit diagram of a detection circuit compatible with a plurality of illumination modes, and FIG. 33 is a block diagram of a first signal processing circuit. 34 is a block diagram of the second signal processing circuit.

The electronic endoscope apparatus shown in FIG. 29 has the endoscope 6
1, a light source device 62, a processor 63, and a monitor 65.

The light source device 62 converts white light emitted from the light source lamp 65 into RGB sequential illumination light by the RGB rotary filter 66, and passes through the diaphragm 67 which dimmes based on the dimming signal from the processor 63. A light collecting lens 69 collects light on the end surface of the light guide 68 of the endoscope 61. The rotary filter 66 is rotated by a motor 78. Further, the diaphragm amount of the diaphragm 67 is controlled by a diaphragm drive circuit 79.

The light source device 62 includes an endoscope 61.
Illumination mode instruction circuit 91A that outputs an ID signal from the ID generation unit 61a or an instruction signal based on an instruction switch (not shown) of the light source operation panel, and a rotation filter control circuit 92A that controls the rotation filter 66 according to the instruction signal. And are provided.

On the basis of the instruction signal from the illumination mode instruction circuit 91A, the rotary filter control circuit 92A inserts / removes the rotary filter 78 into / from the optical path, while the diaphragm drive circuit 79 changes the gain and frequency characteristics. It is like this. At the same time, the illumination mode instruction circuit 91A sends an instruction signal indicating the illumination mode to the processor 63.

For example, when the field sequential illumination mode is selected on the operation panel of the light source device 62, the rotary filter 66 is rotated at a predetermined speed and is inserted at a predetermined position in the optical path to realize the field sequential illumination. To do. On the other hand, simultaneous type (single plate type)
When the illumination mode is selected, the rotary filter 66 is removed from the optical path to realize a continuous white light source.

Normally, whether the illumination mode of the light source is set to the frame-sequential mode or the simultaneous mode is determined by the presence / absence of the filter array of the solid-state image pickup device mounted on the endoscope. Therefore, the mode of the endoscope apparatus is automatically set on the basis of the signal from the ID generating section 61a provided in the endoscope 61. In other words, since the endoscope is attachable to and detachable from the light source device and the processor, it is possible to replace and use an electronic endoscope of either the frame-sequential imaging method or the simultaneous imaging method. Has become.

As a special case, during normal observation with the simultaneous type endoscope, the operation panel is switched to the field-sequential illumination, the RGB component ratio of a specific portion of the image is obtained, and the observed portion is observed. It is conceivable to extract the characteristics of.
In this case, due to the transmission characteristics of the R, G, and B component lights of the filter array, a lattice-striped pattern occurs in the captured image, but this is at a level that does not hinder practical observation.

The processor 63 has a CCD drive circuit 95 for driving a solid-state image pickup device (for example, CCD) 93 of the endoscope 62, and 1 / one of electric signals output from the solid-state image pickup device 93.
and a CDS (correlated double sampling) circuit 97 for suppressing f noise. Further, the processor 63 is
The output of the CDS circuit 97 is processed according to a plurality of illumination modes, that is, imaging modes, and is switchable.
Second signal processing circuits 98a and 98b and switching circuit 9
9 and 9. Further, the processor 63 stores RGB output signals selected by the switching circuit 99.
It has a memory circuit 100, a D / A conversion circuit 101, a low-pass filter (LPF) circuit 102, and a video buffer circuit 103, and outputs an endoscopic image signal to the monitor 64. There is.

Further, the processor 63 has first and second detection circuits 104 and 105 and switching circuits 106, which are provided so as to be switchable according to the illumination mode of the light source, and which have different systems.

The image pickup signal from the solid-state image pickup device 93 is
It is converted into a baseband signal by the CDS circuit 97 and input to the first and second detection circuits 104 and 105 and the first and second signal processing circuits 98a and 98b. The first or second detection circuit 104 or 105 is selected based on the illumination mode signal from the light source device 62, and a dimming signal is sent to the diaphragm drive circuit 79 of the light source. Further, based on the same illumination mode signal, the first or second signal processing circuit 98
a, 98b are selected, and after the predetermined signal processing is performed on the image pickup signal converted into the baseband, the RGB memory 10
Stored in 0. The image data stored in the memory 100 is read out at the same time in synchronization with the standard TV signal, and D /
A-converted, band-limited by the low-pass filter 102, and externally attached to the monitor 6 via the video buffer 103.
4 is output.

FIG. 30 shows a configuration example of the first detection circuit 104 compatible with the frame sequential imaging system. The CDS output signal is a signal for each of the RGB image periods, and is distributed by the switch circuit 107 to a plurality of LPF / hold circuits 108 each including a resistor and a capacitor. The LPF / hold circuit 108 calculates the average value of each RGB image. Hold. The respective RGB average values are multiplied by a plurality of coefficient units / buffers 109, respectively, and then added by an adder 110 and output. At this time, by setting the R, G, B ratio to about 1: 2: 1, the first detection circuit 104
Can output the output as a detection signal by the luminance component Y of the image.

FIG. 31 shows a configuration example of the second detection circuit 105 corresponding to the simultaneous system. The second detection circuit 105 shown in FIG. 31 generates a detection signal of the luminance component Y by integrating and holding the signal of the image period of the CDS output in the LPF / hold circuit 112 composed of a resistor and a capacitor. , Through the buffer 113. During the period other than the image period, the switch circuit 111 opened / closed by the mask signal is OFF.

FIG. 32 shows the first and second detection circuits 104,
An example of a circuit configuration in which the method of 105 can be changed according to two or more illumination modes is shown.

The circuit shown in FIG. 32 is provided so as to be switchable with respect to n different LPF circuits 115 which are provided so as to be switchable according to the illumination mode of the light source, and a frame sequential image pickup signal such as RGB signals. n peak hold circuits 1
19 and n coefficient units / buffers 120, and an adder 121 that adds the n outputs of the coefficient units / buffers 120.

As shown in FIG. 32, the circuit is L
The switching circuits 114 and 116 including n switches are connected to the front and rear stages of the PF circuit 115.
Further, a switching circuit 117 including n switches is connected to the preceding stage of the peak hold circuit 119.

The switching circuits 114, 116, 11
7, and the coefficient unit / buffer 120 is controlled by the switching control circuit 118 based on the illumination mode signal.

With the above configuration, the light source device 62 and the endoscope 6 are
For the combination of 1, the dimming detection method of the processor 63 is adaptively selected.

For example, when an endoscope having a small number of pixels of the solid-state image pickup device is used, the LPF having a small time constant is selected in the detection circuit. In the case of an endoscope having a large number of pixels, the L having a large time constant is used.
PF is selected.

Also, due to the difference in the illumination mode of the light source,
When the gain of the aperture driving circuit 79 of the light source needs to be set differently, the amplification degree of the coefficient unit / buffer is changed based on the illumination mode signal.

33 and 34 show configuration examples of the first and second signal processing circuits 98a and 98b, respectively. In the circuits 98a and 98b, CLMP (clamp) circuits 122, 125 and 127 are circuits for performing direct current regeneration of the CDS output signal and the like. The KNEE circuit is
Decrease the amplification level for input signals above a certain level 1
It is a broken line non-linear circuit. The AGC circuit is a circuit that automatically controls the gain.

Γ126 is a gamma correction circuit and is shown in FIG.
The circuit shown in can be realized by a digital circuit using a look-up table ROM. In addition, the circuit 12 shown in FIG.
6 can be realized by an analog type composite gamma correction circuit that changes the gain based on the level of the luminance component included in the signal.

In the case of the circuit shown in FIG. 33, the switching circuit 129 distributes the γ-corrected frame-sequential signal to each RGB data bus for output. On the other hand, in the circuit shown in FIG. 34, the Y extraction circuits 130 and 131 respectively extract the luminance component and the color difference component from the A / D-converted CCD image pickup signal, and then the matrix circuit 132 converts them into RGB and outputs them. There is.

In the present embodiment, the detection method for automatic light control can be automatically and appropriately switched according to the illumination mode of the light source according to the ID of the endoscope. Further, in this embodiment, a detection method for automatic light control can be set from the operation panel. Therefore, in the present embodiment, even if the endoscope is replaced with an endoscope having a different imaging method or illumination method, the settings of each device can be appropriately set without trouble.

Furthermore, in the present embodiment, it is possible to perform a field-sequential observation with a simultaneous endoscope.

FIG. 35 is an overall configuration diagram of the electronic endoscope apparatus according to the tenth embodiment of the present invention.

The light source device 62A of this embodiment has a light amount detection circuit 133 in addition to the light source device 62 of the ninth embodiment. Further, in addition to the processor 63A of the ninth embodiment, the processor 63A of the present embodiment has a GC for varying the gains of the detection outputs of the first and second detection circuits 104 and 105.
It has an A (gain control amplifier) 134. The light amount detection circuit 133 detects the light amount by using a part of the light emitted from the lamp 65, and controls the gain of the GCA 134 via the isolation 135.

Incidentally, the detection output is the isolation 1
It is supplied to the GCA 134 via 36. Further, the output of the solid-state image pickup device 93 is the isolation unit 13
The data is supplied to the CDS circuit 97 via 7. Other configurations and operations similar to those of the ninth embodiment are designated by the same reference numerals, and description thereof will be omitted.

With the above structure, the rotary filter control circuit 92A of the light source device 62A determines the operation mode based on the ID of the endoscope connected thereto and the instruction of the operation panel, and the rotary filter 66 is moved to the optical path. Insertion / removal, rotation speed / phase control, etc. At the same time, the illumination mode signal is sent to the diaphragm drive circuit 79 for adjusting the amount of emitted light and also to the processor 63A. The switching circuit 9
Reference numerals 9 and 106 select a detection circuit and a signal processing circuit according to the illumination mode signal.

Further, the rotary filter control circuit 92A sends information on the phase, speed, or insertion / removal of the rotary filter to the CCD drive circuit 95. The CCD drive circuit 95 uses the information on the speed, phase or insertion / removal of the rotary filter to
The solid-state image sensor 93 is adaptively driven.

The detection circuit generates a dimming control signal based on the illumination mode of the light source, and the amplification degree of the dimming control signal is varied based on the light amount information of the light source.

In the present embodiment, the light quantity of the light source lamp is detected, and the amplification degree of the dimming control signal is adaptively changed based on the detected value. Therefore, even for a new lamp having a large light quantity. In addition, even for a lamp that is nearing the end of its life in which the amount of light is halved, good dimming control without hunting or response delay can be achieved.

36 to 38 relate to the eleventh embodiment of the present invention. FIG. 36 is a block diagram showing a schematic configuration of the electronic endoscope apparatus, and FIG. 37 is an AGC gain and contour enhancement level in the electronic endoscope apparatus. 38 is a diagram showing the setting relationship of FIG. 38, and FIG. 38 is an explanatory diagram regarding switching of the edge enhancement level.

The electronic endoscope apparatus of the present embodiment is configured so that when the lamp light amount is detected and becomes equal to or larger than a predetermined light amount, a plurality of items such as the setting on the processor side, AGC, and contour emphasis level are simultaneously changed. It was done.

The electronic endoscope device shown in FIG. 36 is an endoscope 140 having a CCD 141 as an image pickup means and a light guide 142 for supplying illumination light, and a light source device for supplying illumination light to the endoscope 140. 143 and a processor 144 that processes the image pickup signal of the CCD to generate a video signal.

In FIG. 36, the image signal of the subject read from the CCD 141 is input to the processor.
In the processor 144, the output signal of the CCD 141 is demodulated by the preprocess circuit 145, and then the AGC circuit 14
6, output as a video signal via the contour enhancement circuit 147 and the video buffer 148.

The AGC circuit 146 is provided with a maximum gain setting circuit 149 for limiting the gain range. With this maximum gain setting circuit 149, at least two types of gain ranges of the AGC circuit 146 can be set. The switching of the gain range is performed by a switching signal from the CPU 150. Such AGC circuits are generally known.

In the contour emphasizing circuit 147, the contour emphasizing level can be switched via the CPU 150 in accordance with an instruction from the switch 152 on the panel 151 as shown in FIG. 38, for example. This is also a known technique.

The contour emphasis level is L (low) / M each time the switch 152 is pressed as shown in FIG.
(Middle) / H (high) are sequentially switched and repeated.

On the other hand, the luminous flux generated by the lamp 153 in the light source device 144 is condensed by the condenser lens 1602,
Further, the light guide 142 transmits the light to the tip of the endoscope and illuminates the subject to be imaged. A diaphragm blade 154 is inserted in the optical path between the lamp 153 and the light guide 142. The diaphragm blade 154 is adapted to automatically adjust the diaphragm amount by a diaphragm control circuit 156 which receives an image signal and detects the amount of illumination light. By this automatic adjustment, the illumination light amount is optimally controlled.

Further, the illumination light is input to the light amount detecting element 157 via another optical path, for example, the half mirror 158. The output of the light amount detection element 157 is input to the determination circuit 159. The discrimination circuit 159 is configured to notify the CPU 150 when the detected light amount becomes a certain value or less.

The relationship between the AGC circuit 146 and the contour emphasizing circuit 147 in the electronic endoscope apparatus having the above configuration will be described with reference to FIG.

When the normal lamp light quantity is obtained, the operating gain range of the AGC circuit 146 is low, for example, 9
It is set to dB. Further, with respect to the contour emphasizing circuit 147, an emphasizing level of, for example, 3/6/9 dB can be selected in accordance with the user's panel setting "L" / "M" / "H".

Next, when the lamp is deteriorated, or when the main lamp is turned off and switched to an emergency light (not shown), the detected light amount decreases and the output of the discrimination circuit 159 becomes active. In this case, the CPU 150 changes the maximum gain of the AGC to, for example, 18 dB to correct the insufficient light amount.
At this time, the contour emphasis level is "L" / "M" /
For example, 0/3/6 dB is set in response to the "H" instruction.

According to this embodiment, since the decrease in the light quantity of the lamp is detected and the AGC gain and the edge enhancement level are simultaneously controlled, the increase in noise due to the increase in AGC gain is suppressed and the image is observed with a good image quality. be able to.

Further, in this embodiment, since the light quantity of the lamp is directly detected by the light quantity detecting element, it is not affected by the image of the subject. Therefore, when the distance to the subject changes, for example, it is possible to prevent a problem that the gain range is switched and the image quality is changed.

39 to 41 relate to the twelfth embodiment of the present invention, FIG. 39 is a block diagram showing the configuration of an electronic endoscope apparatus, FIG. 40 is an explanatory diagram relating to switching of color tone adjustment levels, and FIG. 41 is a color tone. 7 is a chart showing the relationship between adjustment settings and instruction values.

In this embodiment, a color tone adjusting circuit 161 is provided instead of the contour emphasizing circuit 147 in the eleventh embodiment. Other configurations and operations similar to those of the eleventh embodiment are designated by the same reference numerals, description thereof will be omitted, and only different points will be described.

The color tone adjusting circuit 161 adjusts the color of the output image, for example, by changing the amplification degree of two color signals (R / B). Since this is also known means, its details are omitted. The color adjustment circuit 16
The amplification degree (instruction value) of 1 is given from the CPU 150 via the D / A converter 162.

For example, as shown in FIG. 40, switches 164 and 165 for instructing the color tone are provided on the panel 163, and the user can perform color adjustment by operating the switches 164 and 165. it can. The switch 164 corresponds to the color signal R, while the switch 165 corresponds to the color signal B.

The instruction from the panel 163 and the actual D
The data output to the A / A converter 162 is the CPU 150.
At least two ways are retained inside. Figure 41 shows an example of this data. In this example, the color adjustment setting from the panel 163 is provided with steps from +5 to 0 to -5 in FIG. An instruction value (amplification degree) of each of the color signals R and B is set for each stage.

In this embodiment, the threshold value of the discriminating circuit 159 is set lower than that in the eleventh embodiment. This is because only the lighting of the emergency light is detected.

Generally, a xenon lamp is used as a main lamp and a halogen lamp is used as an emergency light in a light source for an endoscope. Since the emergency light is darker than the main lamp, it is possible to detect light quantity as described above. It is possible to detect the emergency light lighting.

In the electronic endoscope apparatus of this embodiment, the operating gain range of the AGC is low when the main lamp is normally lit,
For example, it is set to 9 dB.

On the other hand, with respect to the color tone setting value of the panel 163, the actual color tone instruction value given to the D / A converter 162 is set according to the table shown in FIG. 41 (a) as an example. For example, if the user is (R, B) = (+ 1,-
When the combination of 1) is instructed, the R signal is "20", B
A voltage corresponding to "16" is given to the signal as a color tone instruction signal.

On the other hand, when the emergency lamp is switched to the emergency lamp due to the abnormality of the main lamp, the CPU 150 changes the AGC maximum gain to 18 dB, for example, to correct the insufficient light quantity. At the same time, the table shown in FIG. 34B is used as the color tone instruction value. That is, (R, B) = (+ 1,
For the combination of -1), a voltage corresponding to "14" for the R signal and "20" for the B signal is output, and the color temperature change of the lamp is corrected.

According to this embodiment, since the switching to the emergency light is detected and the AGC gain and the color tone are controlled at the same time, it is possible to prevent the color tone change due to the color temperature change of the light source from being conspicuous due to the AGC gain increase. Therefore, it is possible to observe an image with good image quality.

Further, since the light quantity of the lamp is directly detected by the light quantity detecting element, it is possible to prevent a problem such as a change in color tone, for example, when the distance to the object changes without being influenced by the image of the object. .

42 to 45 relate to the thirteenth embodiment of the present invention, FIG. 42 is a block diagram showing a schematic configuration of an electronic endoscope apparatus, FIG. 43 is a block diagram of a video signal processing circuit, and FIG. FIG. 45 is a block diagram of a formula signal processing circuit, and FIG. 45 is a block diagram of a frame sequential signal processing circuit.

The electronic endoscope apparatus of this embodiment is constructed so that the signal processing of the processor is automatically switched to either the frame sequential method or the simultaneous method according to the setting mode of the light source apparatus.

The electronic endoscope apparatus shown in FIG. 42 has the endoscope 1
66, light source unit 167, processor unit 168
It consists of

A lamp 169 in the light source unit 167.
The illumination light generated by the light passes through the stop 170 and the condenser lens 171 arranged on the optical path, and then the light guide 172.
Incident on. The illumination light transmitted to the tip of the endoscope by the light guide 172 illuminates the subject, and the image of the illuminated subject is converted into an electric signal by the CCD 173 arranged at the tip of the endoscope. This electrical signal is guided to the CDS circuit 174 of the processor unit 168, and the AGC is performed.
The signal is output as a video signal through the circuit 180, the video signal processing circuit 181, and the external output circuit 182.

Inside the light source unit 167, a rotary filter 176 which is inserted into and removed from the optical path and is rotated by a motor 175 is arranged. Rotary filter 176
The insertion / removal of is controlled by the filter control means 177. That is, the light source unit 167 is capable of switching between two illumination modes, a frame sequential type and a simultaneous type. The lighting mode is set on the external panel 1
It is set by a button or the like (not shown) of 78. For the selected mode, the light source side CPU 179 sends a control signal to the filter control means 177 to control whether or not the rotary filter 176 is inserted in front of the lamp. With
The light source side CPU 179 sends a determination signal to the processor side CPU 183 of the processor unit 168 informing the presence / absence of the rotary filter 176.

The CPU 183 on the processor side, which has received the information on the illumination mode from the light source unit 167, controls the video signal processing circuit 181 to perform a signal processing operation suitable for the illumination mode. That is, signal processing is performed by either a frame sequential method or a simultaneous method.

FIG. 181 shows a block diagram of the video signal processing circuit 181. The video signal processing circuit 181 is configured to select the frame sequential signal processing or the simultaneous signal processing according to the determination signal sent from the light source unit 167.

The video signal processing circuit 181 uses the AGC1
A / D converter 184 for inputting the output of 80, switch 185, frame sequential signal processing circuit 186, simultaneous signal processing circuit 187, switch 188, matrix circuit 189, and D / A converter 190. And a post-processing circuit 191.

The frame sequential signal processing circuit 186 and the simultaneous signal processing circuit 187 are arranged in parallel, and the switches 185 and 188 are interposed in the front and rear stages thereof. The switches 185 and 188 can be switched by a control signal according to the illumination mode.

For the frame sequential type and the simultaneous type, normally,
The endoscope shall be replaced. An endoscope for simultaneous imaging has a color mosaic filter arranged in front of a CCD. On the other hand, an endoscope that captures images in a frame-sequential system is not provided with a color mosaic filter.

The processor-side CPU 183 sends to the matrix circuit 189 a coefficient for correcting the difference between the color characteristic of the frame sequential rotation filter 176 and the color characteristic of the CCD color mosaic filter in the simultaneous equation.

FIG. 44 shows a configuration example of the frame sequential signal processing circuit 186.

In the frame-sequential system, RGB sequential signals are input to the same circuit 186 in time series, and first, the black level adjusting circuit 1
The black level is adjusted by 92, and then the white balance (hereinafter abbreviated as WB) circuit 193 performs white balance adjustment. The white-balanced signal is
The gamma correction circuit 194 performs gamma correction, and the memory 195 performs RGB correction.
Sequential signals become R / G / B signals which are synchronized.

FIG. 44 shows a structural example of the simultaneous signal processing circuit 187.

A color-difference line-sequential signal is input to the circuit 187, and is converted into a luminance signal and a color-difference signal by the color separation circuit 196. The brightness signal and the color difference signal are adjusted in black level by the black level adjustment 197, and then converted into RGB signals by the color processing circuit 199. For each signal converted into R / G / B, the W. White balance adjustment is performed by the B circuit 199, and each adjusted signal is subjected to γ correction by the γ correction circuit 200 and output to the matrix circuit 189 via the memory 201.

In this embodiment, the frame sequential method and the simultaneous method can be applied, and the switching setting can be automatically and easily performed.

Further, in this embodiment, the coefficient of the matrix circuit 189 can be changed according to the mode of the frame sequential type / simultaneous type to cope with the difference in the characteristics of the rotary filter and the color mosaic filter. In other words, even if the color reproducibility is in different modes, it is possible to maintain the uniformity and provide an image that is easy to observe.

46 to 48 relate to the fourteenth embodiment of the present invention, FIG. 46 is a block diagram showing the configuration of a signal processing unit of an electronic endoscope apparatus, FIG. 47 is a configuration diagram of a light source unit, and FIG. It is a flowchart regarding white balance adjustment.

The electronic endoscope apparatus of this embodiment is an apparatus capable of processing signals of both single plate color (simultaneous) type image pickup and frame sequential image pickup. In addition, the light source section shown in FIG.
6 is connected to the signal processing unit. And
The electronic endoscope device is configured to detect the occurrence of an abnormality in the light source unit and switch to the emergency light, and change the white balance operation of the signal processing unit.

In the signal processing unit shown in FIG. 46, the circuit required to perform different operations at the time of single-plate color image pickup and at the time of frame sequential image pickup is composed of an FPGA (Field Programmable Gate Array). CPU2
By changing the wiring information (FPGA program) downloaded from 11, signal processing by both methods is possible. The FPGA program is CSIO2O
Given through 9. Further, in the FPGA circuit, the processing procedure and the like are controlled according to the process control provided via the parallel I / O controller (PIO) 235. In the figure, the circuit composed of FPGA is
It is shown with a double border.

The structure and operation of the electronic endoscope device will be described below.

The CCD 210, which is the image pickup means, is provided in, for example, an endoscope. CCD 210
Is suitable for the image pickup method emitted by the light source unit and takes an image under the illumination light and outputs an image pickup signal. The image pickup signal of the CCD 210 is supplied to the pre-signal processing unit, processed by the processing operation suitable for the image pickup system, and, for example, R, G, B video signals are output.

First, the signal processing for single-plate color image pickup will be described.

In FIG. 46, SSG (synchronous
The drive signal generated by the signal generator) 212 is converted into a predetermined voltage by the CCD driver 213 and output. The CCD 210 has a color mosaic filter (not shown) arranged on the image pickup surface. CCD 210 is
It is driven by the CCD drive signal of the CCD driver 213. The SSG 212 is adapted to generate a drive signal for single-plate color imaging.

The readout signal from the CCD 210 is the CD
The signal is demodulated by the S (correlated double sampling) circuit 214 and converted into a digital signal by the A / D converter 216 via the AGC amplifier 215. The signal immediately after the A / D conversion is input to the color separation circuit 217 and the AGC detection circuit 218. The AGC detection circuit 218 generates an AGC control signal and feeds it back to the AGC amplifier 215 via a D / A converter 219. With this configuration, the AGC operates and sufficient brightness can be obtained even when a dark subject is imaged.

The output of the CDS circuit 214 is A / D converted by the A / D converter 220 to adjust the amount of light emitted from the light source section, and is input to the dimming detection circuit 221.

The dimming detection circuit 220 calculates the average level and brightness distribution of the image and outputs it to the CPU 211. The CPU 211 performs light control calculation and outputs the result to the light source unit via the serial I / O controller (SIO) 222. The video signal after AGC adjustment is separated into a luminance (Y) and color difference (RY, BY) signal by a color separation circuit 217, and color processing unique to various endoscopic images is performed by a color processing circuit 223. Done. Each signal after the color processing is input to the white balance detection circuit 224, and the color balance information is output to the CPU 211.

When the white balance is set, the CPU 211 calculates a color correction value based on the detection result and outputs it to the white balance (WB) control circuit 225.
This correction value is multiplied by each color difference signal to obtain the correct color balance.

The video signal subjected to the color correction calculation is output to the γ complement circuit 2
After .gamma. Correction by 26, the memory input control circuit 227
Are stored in the three field memories (FM) 228, respectively. The luminance and color difference video signals read from the memories 228 are converted into RGB signals by the matrix circuit 229.
The signal is converted into a signal, the color tone is corrected by the color tone circuit 230, and the data from the CPU 211 is superimposed in the superimpose 231. Then, the signal on which the necessary character is superimposed is D / A converted by the three D / A converters 232 and then output as an RGB video signal to the outside.

The superimposed character is the VRAM 23.
3 and the timing of superimposition is controlled by the CRT controller 234.

Next, the signal processing operation at the time of frame sequential imaging will be described.

As the CCD 210, one having no color mosaic filter on the image pickup surface is used. In addition, an FPGA program for frame-sequential imaging is given to the circuit configured by the FPGA of the signal processing unit.

RGB read out from the CCD 210
The frame-sequential signal is the same as the CDS / AG used for single-panel color imaging
After the C processing is performed, it is input to the color separation circuit 217.
Since there is no need to perform color separation processing during frame sequential imaging, this circuit 217 functions as a simple bypass circuit. Thereafter, color processing and white balance adjustment are performed, and the signal is input to the memory input control circuit 227. Here, RG
Control is performed so that the video signal input as the B sequential signal is distributed to the three frame memories 228.

Since the matrix operation in the latter stage is not necessary as in the case of color separation, the R synchronized by the memory 228 is synchronized.
GB is also bypassed by the matrix circuit 229 and input to the color tone circuit 230 in the subsequent stage. Subsequent video signal processing is the same as in the single-chip color imaging method.

In the light source section shown in FIG. 47, the dimming signal transmitted from the signal processing section is input to the CPU 237 via the SIO 236. The CPU 237 uses the dimming signal to generate a parallel I / O controller (PIO).
The dimming control circuit 239 is controlled via 238 to drive the diaphragm blade 240 for dimming light adjustment.

Further, an instruction from the panel switch 241 is read by a PKDI (programmable key / display interface) 242, and LED display control, lamp control, rotary filter control, etc. are performed. As an example, when the panel switch 241 instructs the single-plate color imaging mode or the frame sequential imaging mode, the rotary filter 2
Reference numeral 45 switches between insertion and removal of the illumination light source and the light guide 244 with respect to the optical path. In addition, the fact that the mode has been switched is communicated to the CPU 211 of the signal processing unit via the SIOs 236 and 222. Reference numeral 248 is a panel LED. The rotary filter 245 is a motor 250 controlled by a rotary filter control circuit 249.
It is designed to be rotated by.

By the way, in the light source section of the endoscope apparatus, in order to secure the field of view even when the main illumination lamp 243 (mainly the xenon lamp is used) goes out due to an abnormality during observation, An emergency light 246 such as a halogen lamp is provided. When the main lamp 243 is turned off, the CPU 237 of the light source unit detects this and turns on the emergency light, and communicates this to the CPU 211 of the signal processing unit via the SIOs 236 and 222. The lamp control circuit 247 controls switching of lamps.

FIG. 48 is a flowchart of interrupt processing in the CPU of the signal processing section.

When the SIO 222 receives data from the light source unit, an interrupt occurs and the processing task shown in FIG. 48 is activated. When the received data is the code corresponding to the switching of the light source (emergency light detection) in step S1, the CPU 211 reads the previously stored WB correction value for the halogen lamp in step S2. Then, the correction value is output to the WB balance control circuit 225.
In step S3, the WB balance control circuit 225
Then, a correction value corresponding to each color difference signal (in the single-plate color image pickup mode) or each RGB signal (in the frame sequential image pickup mode) is multiplied to obtain a standard color reproduction when the halogen lamp is illuminated.

According to the present embodiment, when the main lamp is abnormally turned off in the light source section, it is switched to the emergency lamp illumination, and this is communicated to the signal processing section to reset the white balance corresponding to the type of the lamp. It is possible to prevent a sudden change in color reproduction that occurs when the emergency light is turned on. This allows
Even if the lamp is switched, it is possible to obtain an observation image with good color reproducibility.

FIG. 49 is a flowchart relating to white balance adjustment according to the fifteenth embodiment of the present invention.

The hardware configuration of the electronic endoscope apparatus of this embodiment is the same as that of the 14th embodiment, and therefore its explanation is omitted.

The flowchart shown in FIG. 49 shows a part of the timer interrupt processing of the CPU of the signal processing unit.
This task describes an operation for performing necessary processing at fixed time intervals, such as reading a switching instruction from the panel and controlling LED lighting. 1 of these processes
As one of them, a process of detecting a sudden change in color of an image pickup signal is performed. That is, in steps S4 and S5, the data is read from the white balance detection circuit 224 and compared with the past color data. In step S6, when the lamp of the light source unit is switched from the normal illumination of the xenon lamp to the emergency lamp illumination of the halogen lamp, the image of the same subject suddenly changes in the direction in which the color temperature decreases. Therefore, the lamp change can be detected from the image signal.

When the switch to the emergency light is detected, the CP
U211 performs the color correction operation described below. That is, in steps S7 and S8, the current white balance setting value is read out, and the correction calculation corresponding to the change in the color temperature of the lamp is performed. In step S9, the calculation result is written in the WB balance control circuit 225, and the white balance is reset.

According to this embodiment, since the lamp change of the light source unit is detected by the color information extracted from the image signal and the white balance is shifted, even when the light source unit which does not transmit the emergency light detection signal is connected. It is possible to automatically perform color correction when the emergency light is turned on. Further, in this embodiment,
As the color correction operation, since the correction calculation is performed using the color correction value with respect to the current set value, it is possible to perform more accurate color correction as compared with the fourteenth embodiment.

50 to 53 relate to the sixteenth embodiment of the present invention. FIG. 50 is a block diagram of a white balance detection circuit at the time of single-plate color image pickup, and FIG. 51 is a block of the white balance detection circuit at the time of frame sequential image pickup. 52 is a timing chart of the circuit shown in FIG. 50, and FIG. 53 is a timing chart of the circuit shown in FIG.

Other than that, the hardware configuration of the electronic endoscope apparatus of the present embodiment is the same as that of the 14th embodiment, and therefore its explanation is omitted.

Switching between the detection circuit at the time of single-plate color imaging shown in FIG. 50 and the detection circuit at the time of frame sequential imaging shown in FIG. 51 is performed by reprogramming the FPGA as described above.

When the single-plate color imaging mode is instructed from the panel 241 of the light source section, the CPU 237 of the light source section detects this and switches the illumination mode to the white light illumination by separating the rotary filter 245 from the optical path. At the same time CPU 237
Communicates that the imaging mode has been changed to the signal processing unit via the SIOs 236 and 222. CPU of signal processing unit
In response to this, the 211 reprograms the FPGA of each unit. Of these, the WB balance detection circuit 224 is shown in FIG.
Is programmed like.

The color difference signal (RY / BY) is input to the two input terminals of the white balance detection circuit 224. The white balance detection circuit 224 is provided with an averaging circuit 251 for integrating the color difference signals and a register 252 for storing the average value. These are the control signal generation circuit 253.
Is controlled by.

As shown in FIG. 52, the input color difference signals have already been synchronized by the color separation circuit 217, so RY and BY are simultaneously input. Therefore, the resetting of each averaging circuit 251 and the loading to the register are common to the two color differences. The timing of this processing is loaded after the end of one screen, and reset (res) is performed after this loading.

On the other hand, in the frame sequential imaging mode, the white balance detection circuit 224 receives RGB sequential signals in time series at the RY input terminals in the single plate color imaging mode, and signals at the other terminals. Not done. Therefore, only one averaging circuit 251 is provided and its output is 3
The circuit configuration is distributed to one register 252. Then, the control signal generation circuit 253 generates a control signal so that the average value of each of the RGB screens is stored in these three registers 252. That is, as shown in FIG.
Is reset for each screen. Also, load
-R, load-G, load-B) is executed after the end of the screen of the color corresponding to each register 252.

According to the embodiment having the above configuration, since the white balance circuit is changed depending on the type of illumination of the light source,
These can be automatically set without manually switching, and images can be taken by different imaging methods.

54 to 58 relate to the seventeenth embodiment of the present invention, FIG. 54 is a structural diagram of an optical system in a light source section, and FIG. 55 is an explanatory diagram showing a shape of diaphragm blades and a positional relationship with an optical axis. 56 is a correlation diagram between the aperture of the diaphragm and each color in the CCD output, FIG. 57 is a flowchart of timer interruption, and FIG. 58 is a flowchart for obtaining a correction value of white balance.

The electronic endoscope apparatus of the present embodiment is configured to detect the diaphragm amount and set the white balance in accordance with the detected diaphragm amount.

Other than that, the hardware configuration of the electronic endoscope apparatus of the present embodiment is the same as that of the 14th embodiment, and therefore its explanation is omitted.

In the optical system for the light source section shown in FIG.
The luminous flux generated by the lamp 243 is emitted from the first lens 2
After being focused by 55, the amount of light is controlled through the diaphragm blade 240, the light is incident on the second lens 256. In the frame sequential illumination mode, this incident light is transmitted by the rotary filter 24.
The third lens 257
The light is condensed by and guided to the light guide 244.

The diaphragm blade 240 shown in FIG. 55 is installed so as to cross the optical axis of the illumination light, and has a structure for controlling the amount of passing light depending on the angle at which the optical path is blocked. The aperture blade 240 has a fan-shaped notch 2 for controlling the amount of light.
58 and a slit portion 259 are provided. The slit portion 259 has an effect of preventing the passing light amount from abruptly changing in response to a change in the angle of the diaphragm blades 240 during the change from the small aperture amount region to the large aperture amount region.

However, it has been clarified that the diffraction effect occurs when the light flux passes through the slit portion 259. Therefore, in a region where the diaphragm amount (diaphragm aperture) is large, the color balance of the illumination light changes, for example, as shown in FIG. Therefore, in the conventional endoscope apparatus, the color changes especially when the image is picked up near the subject.

FIG. 57 is a signal processing section C of this embodiment.
It is a figure which shows a part of flow of the timer interruption process of PU. This task describes an operation for performing necessary processing such as output of a light amount control signal, reading of a switch from a panel, and LED lighting control at fixed time intervals.

When the timer interrupt process is activated after the elapse of a certain period of time, in steps S10, 11 and 12, the CPU
Reference numeral 211 reads the brightness information from the dimming detection circuit 221, calculates the aperture value for obtaining the optimum light amount, and SIO2
It outputs to the light source part via 22, 236. At this time, if it is determined in step S13 that the aperture value, which is the calculation result, is equal to or larger than the predetermined value, the CPU 211 simultaneously resets the white balance in step S14 and subsequent steps. That is,
In steps S14 and S15, the current white balance setting value and the color correction value previously stored in the CPU are read. After that, in step S16, the CPU 211 performs a correction calculation on the current set value based on the color correction value, and resets the white balance in step S17.

FIG. 58 is a flow chart for obtaining a white balance correction value for the aperture amount.

When the white balance operation is instructed from the key switch of the panel 241, this task is started. After the dimming operation is completed in step S21 and the appropriate brightness is set, the color information is read from the white balance detection circuit 224 in step S22, and the color correction value for obtaining the correct color reproduction is obtained in step S23. Calculate and output. Then, in step S24, the white balance is set.

Next, in order to obtain the white balance correction value by sequentially changing the aperture value to the maximum (minimum light amount), a predetermined value is output to the dimming control circuit 239 in step S25,
Increase the aperture. Then, after the aperture operation is completed in step S26, color information is fetched and white balance correction values for each aperture value are calculated and stored in steps S27, 28, and 29. This operation is repeated until the aperture becomes maximum in step S30.

According to the embodiment having the above-mentioned configuration, the white balance is reset according to the detected aperture value, so that the color temperature change caused by the change in the aperture amount is corrected to obtain an appropriate color. You can observe the image of.

In this embodiment, the aperture value is calculated on the signal processing unit side, but this is performed on the light source unit side and the determined aperture amount is communicated to the signal processing unit. Even if it is, the same effect can be obtained.

59 to 63 relate to the eighteenth embodiment of the present invention. FIG. 59 is a block diagram of a light source section, FIG. 60 is a flowchart of white balance setting in the special light mode, and FIG. 61 is an optical system of the light source section. Block diagram showing the configuration,
62 is a perspective view showing the configuration of single-wavelength illumination, and FIG. 63 is a perspective view showing the configuration of three-wavelength illumination.

In the electronic endoscope apparatus of this embodiment, the light source section can emit special light such as infrared rays in addition to the normal white illumination light. Then, the electronic endoscope device is configured to detect a special light observation mode for detecting that illumination other than white light is being performed, and to set the white balance to a predetermined value during illumination other than white light. ing.

In addition, since the hardware configuration of the electronic endoscope apparatus of this embodiment is the same as that of the 14th embodiment, FIG.
6 will be omitted, and only different points will be described.

By the way, in the field of electronic endoscope, observation with special light such as infrared rays may be performed for the purpose of blood flow observation. Illumination methods of this special light include a method using a single wavelength and a method using a plurality of wavelengths.

When performing single-wavelength illumination, the image is often observed as it is on the monitor, so a filter dedicated to special light can be attached to the light source, and this filter can be inserted in the optical path. By doing so, single wavelength illumination is performed.

In the case of observing with a plurality of wavelengths (in this case, an image processing device is often used to quantitatively compare images of respective wavelengths), RGB for field sequential illumination is used.
Illumination is performed by inserting a rotary filter having a filter for each wavelength instead of the rotary filter for use. The insertion / removal of these special light filters can be designated by the panel switch 291 of the light source unit shown in FIG. 59, and the CPU 237 of the light source unit controls them and at the same time transmits control information to the signal processing unit. To do.

FIG. 61 shows the configuration of the illumination optical system in the light source section of the electronic endoscope apparatus. The light flux emitted from the lamp 260 includes a first lens 261, a rotary filter 262 for three-wavelength illumination, a filter 263 for single-wavelength illumination, and a second filter.
The light enters the light guide 265 connected to the illumination optical system of the endoscope insertion portion via the lens 264.

The single-wavelength illumination filter 263 shown in FIG.
As shown in FIG. 2, a plurality of optical filters 271 to 273 are attached to the disc-shaped member (turret) 270. The plurality of optical filters 271 to 273 have different transmission wavelength ranges. Further, the disc-shaped member (turret) 270 is provided with a filter non-mounting portion 274 for use when single wavelength illumination is not performed.

The turret 270 can be rotated by a motor 275. By rotating the turret 270 and stopping it at a position where a desired optical filter is inserted in the optical path, an arbitrary optical filter can be selected. ing. The rotation of the filter selection motor 275 is controlled by the single wavelength illumination control circuit 276 based on the instruction of the CPU 237 shown in FIG.

On the other hand, as shown in FIG. 63, the turret 280 of the three-wavelength illumination filter 262 is the motor 28.
4 rotates in synchronization with the image signal. During special light observation, by using the special light turret 280 in which a plurality of optical filters 281 to 283 having different transmission wavelength ranges are arranged, it is possible to obtain sequential illumination light of arbitrary three wavelengths.

Further, during normal observation, by replacing the turret with three types of optical filters of red, green, and blue, it is possible to obtain sequential illumination light of arbitrary three wavelengths.

The entire system of the rotary filter can be moved by the attachment / detachment motor 285.
It is also possible to retract 62 from the optical path and stop the illumination light of three wavelengths sequentially.

As shown in FIG. 63, the support column of the moving member 287 is provided with a rotation motor 284 having the turret fixed to the rotation shaft. The base portion of the moving member 287 is moved by the rotation of the attachment / detachment motor 285, and is inserted into and removed from the optical path. The rotation motor 284 and the attachment / detachment motor 285 are controlled by a three-wavelength illumination control circuit 286 under the instruction of the CPU 238 shown in FIG.

Now, assuming that the single-wavelength illumination light from a certain optical filter is selected by the panel switch 291, the CPU 237 rotates the single-wavelength illumination turret 263 to select the designated optical filter and
The turret for three-wavelength illumination is moved and retracted from the optical path. This allows illumination with a single wavelength.

When the three-wavelength illumination is selected,
The CPU 237 rotates the single-wavelength illumination turret 263 to the non-filter mounting portion 274 and inserts the three-wavelength illumination filter 280 in the optical path to perform three-wavelength sequential illumination.

FIG. 60 is a flowchart of the SIO reception interrupt processing of the CPU of the signal processing unit in this embodiment.

When data is received from the light source unit, SIO
An interrupt is generated from 222, and the processing of FIG. 60 is performed. When the received data corresponds to the shift to the special light observation mode, the processing described below is performed. If the special light observation mode is the single wavelength observation in step S31, white balance adjustment processing is performed in steps S32 to S34 to set the RGB image output levels to the same level. That is, when observing a single wavelength, the image is monochrome.

If it is determined in steps S31 and S35 that the special light observation mode is the multi-wavelength observation mode, step S31.
The white balance is reset at 36, and each image is output to the outside with the same amplification degree.

According to the embodiment having the above-described structure, the white balance circuit can be reset so that the output image is displayed in monochrome when the special light of a single wavelength is observed, and an easily viewable image can be displayed. In addition, in the present embodiment, during special light observation of a plurality of wavelengths, the images of the three wavelengths obtained are output at the same level ratio, so that diagnosis and evaluation by an image processing device or the like can be easily performed. is there.

In this embodiment, the white balance control is performed so as to obtain a monochrome image when observing a single wavelength, but it will be understood that a color tone other than monochrome can be easily set.

64 to 69 relate to the nineteenth embodiment of the present invention. FIG. 64 is a schematic configuration diagram of an electronic endoscope, FIG. 65 is an explanatory diagram of a monitor screen, and FIG. 66 is A of the screen shown in FIG. 67 is a waveform diagram of the video signal of the scanning line, FIG. 67 is an explanatory diagram of AGC detection, FIG. 68 is a circuit diagram showing one configuration of the GCA control unit, FIG.
9 is a circuit diagram showing another configuration of the GCA control unit.

The electronic endoscope apparatus according to this embodiment includes the endoscope 30.
1, a light source unit 302, a signal processing unit 303, and a monitor unit (not shown). This electronic endoscope apparatus controls the irradiation method of the light source unit 302 by switching to continuous irradiation or flash irradiation, and at the time of flash irradiation, sets a threshold value in AGC detection of the signal processing unit 303 or detects a detection range. It is configured to change.

The light emitted from the xenon lamp 304 of the light source section 302 passes through the light guide 305 to the endoscope 30.
1 The subject is illuminated from the front. The reflected light from the subject enters the CCD 306, which is also arranged in front of the endoscope 301. The CCD 306 is driven by a drive signal generated by a CCD drive circuit 307 inside the signal processing unit 303, and photoelectrically converts incident light into an electric signal.
This electric signal is a signal line 308 that passes through the endoscope 301.
Via the CDS circuit 309 in the signal processing unit 303, and is input to the AGC circuit 310. And the CDS
The output signal of the circuit 309 is AGC controlled by the AGC circuit 310 so as to have a certain constant level, and is input to the A / D converter 314.

The AGC circuit 310 is the CDS circuit 30.
Gain control amplifier 311 for amplifying the output of 9
And a GCA control unit 312 that detects the output of the gain control amplifier 311 and controls the gain of the amplifier.

The output of the gain control amplifier 311 is passed through the A / D converter 313 and the main screen memory 314.
And the child screen memory 315. Writing / reading of the parent screen memory 314 and the child screen memory 315 is controlled by the SSG 316.

In normal times, a moving image whose contents are successively updated is output from only the main screen memory 314 and displayed on the monitor.

At the time of freezing, updating of the contents of the parent screen memory 314 is prohibited and still images are output, while moving images of which the contents are sequentially updated are output from the child screen memory 315. After the still image and the moving image are combined, the D / A
It is converted and displayed on the monitor.

The CCD drive circuit 307 drives the CCD 306 in the shutter mode under the control of the CPU 300 on the processor side which receives the freeze command. Further, the SSG 316 reads the parent screen memory 314 in the freeze mode under the control of the processor-side CPU 300 that receives the freeze command.

The image data read from the memories 314 and 315 are superposed by the adder 317 and input to the output device such as the monitor through the D / A converter 318 and the like.

On the other hand, the electric signal output from the CCD 306 is the same as the light control circuit 31 in the signal processing unit 303.
It is detected by 9 and a dimming signal is generated. The dimming circuit 319 operates the diaphragm 32 in the light source unit 302 according to the dimming signal.
The aperture amount of 0 is adjusted to control the light amount for illuminating the subject to be appropriate. In addition, the dimming circuit 319
When the proper exposure amount is detected, the detection pulse is output to the processor side CPU 300.

The light source side CPU 321 of the light source unit 302 controls the irradiation mode of the xenon lamp 304 via the xenon lamp power supply 322. In this embodiment, there are a continuous mode in which light is continuously emitted and a flash mode in which intense light is emitted intermittently. The light source side CPU 32
No. 1 outputs the AGC detection control signal to the GCA control unit 312 of the signal processing unit 303 at the same time when the flash mode is instructed.

The freeze operation in the CCD 306 shutter (element shutter) mode will be described below. When the freeze command is input by the operation of the observer, CC
The D drive circuit 307 generates a drive signal for causing the CCD 306 to perform a shutter operation. This freeze instruction
Since it is given to the CPU 321 of the light source unit 302, the same CP
The U 321 instructs the xenon lamp power supply 322 to switch the irradiation mode so as to perform the flash irradiation. When the xenon lamp 304 irradiates the flash, the light amount is increased so as to make up for the light amount shortage during the shutter operation of the CCD, and when the proper exposure amount is reached, the processor side C
The image on the main screen is frozen under the control of the PU 30. At this time, the still image at the time when the proper exposure amount is obtained is displayed on the parent screen on the monitor, while the moving image is displayed on the child screen.

Since the irradiation light continues to be irradiated with light for a certain period of time after the freeze irradiation, the CCD 306 which has returned to the normal drive after the freeze irradiation is temporarily in the over-exposure state. Since the AGC circuit 310 reacts as it is, an unsightly image such as hunting is displayed on the sub screen.

Therefore, in this embodiment, the light source side CPU 32
AGC output with flash irradiation command from 1
The GCA control unit 312 switches the AGC detection method according to the detection control signal. FIG. 65 shows a display screen of the monitor. For the sake of explanation, it is assumed that the upper right portion of the parent screen is sufficiently illuminated, and the other shaded portions are insufficiently illuminated.

If flash irradiation is performed in order to obtain an appropriate exposure amount in the freeze operation in the CCD shutter mode, the video signal of the portion indicated by the scanning line A in FIG. 65 becomes as shown in FIG. The video signal in the upper right part of the screen is temporarily saturated due to flash irradiation. The GCA control unit 312 sets a predetermined threshold value for the video signal and switches the control method so as to execute the gain control of the GCA 311 using only a signal below this threshold value.

The AGC control method may be switched as follows.

The GCA control section 312 divides the effective screen into a plurality of areas as shown in FIG. 67, and selects, for example, a peripheral area of the screen (in the figure Only the video signal in the hatched area) is used to change the processing to control the gain.

For example, when observing the stomach wall or the like,
The central part of the screen is saturated with respect to the peripheral part of the screen. Therefore, it is effective to change the AGC operation using only the video signal in the peripheral area of the screen, which is less likely to be saturated.

FIG. 68 shows a specific circuit configuration example of the GCA control unit 312. The CDS output passes through the inverting amplifier IC1 and is input to the limiter circuit IC2. Limiter circuit I
At C2, the switch S receiving the AGC detection control signal
According to the voltages E1 and E2 selected by W1, the CD
A limiter is applied to the S output, and a signal with that limit as the upper limit is output. This limiter signal is converted into a GCA control voltage by the LPF / hold circuit 323 only by a desired signal in one screen by the switch SW2 which is controlled to open / close by a mask signal. The LPF / hold circuit 323 is composed of a resistor, a capacitor, and a buffer.

FIG. 69 shows another configuration example of the GCA control unit 312. The GCA control unit 312 changes the detection range by generating a mask signal by the mask signal generation circuit 324 according to the AGC detection control signal without applying a limiter to the input CDS output.
The timing of generating the mask signal is the vertical synchronization signal V
The timing is synchronized with D and the horizontal synchronizing signal HD.

According to this embodiment, during freeze operation in the CCD shutter mode, flash irradiation for obtaining an appropriate exposure amount is performed, and even if part of the image is saturated, the threshold value for AGC detection is set. By controlling the setting and the target range of detection, it is possible to prevent the hunting of the moving screen due to the AGC reacting to the video signal that is temporarily saturated by the flash irradiation.

70 and 71 relate to the twentieth embodiment of the present invention. FIG. 70 is a schematic block diagram of an electronic endoscope, and FIG. 71 is a timing chart showing the operation of the apparatus shown in FIG.

In the electronic endoscope apparatus of this embodiment, the irradiation method of the light source section is controlled by switching to continuous irradiation or flash light irradiation, and at the time of flash light irradiation, the operation of the AGC is cut off to maintain a constant gain. It is configured. Other configurations and operations similar to those of the nineteenth embodiment are designated by the same reference numerals, and description thereof will be omitted.

In the device of this embodiment, the signal processing unit 302 of the nineteenth embodiment is replaced with the AGCon / o output from the light source side CPU 325 instead of the GCA control unit 312.
G which controls the operation / cutoff of AGC by the ff control signal
It has a CA control unit 326.

With the above structure, the freeze operation in the CCD shutter (element shutter) mode will be described with reference to FIG.

First, it is assumed that the CCD shutter mode command shown in FIG. 71 (a) is selected. In this state,
When the freeze command shown in FIG. 71B is input by the operation of the observer, the CCD drive circuit 307 causes the CCD 306 to perform the shutter operation. At this time, the light source side CP
U325 instructs the xenon lamp power supply 322 to switch the irradiation mode shown in FIG. 71 (c) to perform flash irradiation. When the xenon lamp 304 irradiates the flash, the light amount is increased so as to compensate for the light amount shortage during the shutter operation of the CCD, and the dimming circuit 319 detects the proper exposure amount, and when the proper exposure amount is reached, the processor side C
The appropriate exposure amount detection pulse shown in FIG. 71 (d) is output to PU30. The processor side CPU 30 receives the detection pulse and freezes the image on the main screen by SS.
The reading of the parent screen memory 314 is controlled via G316. In this way, the image at the time when the proper exposure amount is obtained is displayed as a still image on the main screen on the monitor.

On the other hand, since the child screen is a moving image display, in order to prevent the unsightly image such as the above-mentioned hunting from being displayed, in the present embodiment, the following operation changes are made.

The AGCoff control signal shown in FIG. 71 (e) is sent together with the flash irradiation command by the GCA control unit 326.
Given to. Then, based on the switching information to the flash irradiation mode, the GCA control unit 326 suspends the operation of the AGC and holds the gain control voltage of the GCA 311 until the flash irradiation is completed.

According to this embodiment, in order to obtain the proper exposure amount during the freeze operation in the CCD shutter mode,
Even when flash irradiation is performed, the AGC control is cut off and the gain is held. Therefore, in this embodiment,
It is possible to prevent an unsightly image such as hunting caused by the reaction of the AGC from flash irradiation from being displayed on the monitor, and it is possible to obtain an appropriate observation image.

FIG. 72 is a schematic block diagram of an electronic endoscope apparatus according to the 21st embodiment of the present invention.

The electronic endoscope apparatus according to this embodiment includes the light source section 32.
8 is a normal light, the xenon lamp 304 and the emergency light 3
And 31 are provided. The light source unit 328 is configured to switch to the emergency light 331 and illuminate when the xenon lamp 304 is burnt out. Other configurations and operations similar to those of the nineteenth embodiment are designated by the same reference numerals, description thereof will be omitted, and only different points will be described.

In the light source section 328, the light emitted from the xenon lamp 304 passes through the filter 332 for reducing the light quantity, and then the light guide 30.
It is incident on 5. Illumination light that has passed through the light guide 305 in the endoscope 301 is irradiated to the subject from the front surface of the endoscope, and the reflected light is incident on the CCD 306 also arranged on the front surface of the endoscope. This CCD 306 has a signal processing unit 329.
It is driven by a drive signal generated by an internal CCD drive circuit 307 to photoelectrically convert incident light into an electric signal. The electric signal is auto-gain controlled by the GCA 333 in the signal processing unit 329 via the cable 308 in the endoscope, and is output to the output device such as the monitor via the signal processing circuit 334.

The GCA 333 is composed of the gain control amplifier 311 and a GCA control section 340 which changes the gain in accordance with a signal provided from the light source section 339 for discriminating lamp switching.

On the other hand, the CPU 335 in the light source section 328 is
The current value flowing through the xenon lamp power supply 336 that supplies power to the xenon lamp 304 is monitored. Here, due to the sudden decrease in the current value, the xenon lamp 304
When the CPU 335 determines that the emergency light 331 is disconnected, the CPU 335 controls the motor 338 through the drive circuit 337 to move the emergency light 331 on the optical axis and turn on the emergency light 331.

Here, in the electronic endoscope apparatus, an emergency light having a lower light quantity than that of a diagnostic xenon lamp is generally used, and when the emergency light is turned on due to the disconnection of the xenon lamp, a monitor image is displayed. It gets darker than when using a xenon lamp.

Therefore, in this embodiment, the lamp discriminating circuit 339 provided inside the light source discriminates whether the currently lit lamp is a diagnostic xenon lamp or an emergency lamp. The lamp discrimination circuit 339 discriminates based on the current value of the CPU 335 or the switching instruction.

If it is determined that the emergency light lamp is turned on, the maximum gain of the AGC is increased to the GCA gain control section 340 of the GCA circuit 333 than the value set when the examination xenon lamp is turned on. Control to let.

According to the present embodiment, even if the emergency light is switched on due to the disconnection of the xenon lamp for examination generated during the observation with the endoscope, the maximum gain of the AGC is set to a low value in response to the reduction of the illumination light amount. Thus, an appropriate visual field can be secured and an observation image with sufficient brightness can be obtained.

When the emergency light is turned on, it is considered an emergency and S
The same effect can be obtained by changing the variable range of the gain in order to secure a sufficient field of view even if / N is sacrificed.

73 and 74 relate to the 22nd embodiment of the present invention, FIG. 73 is a schematic block diagram of an electronic endoscope apparatus, and FIG. 74 is a block diagram showing a structural example of a GCA control unit.

The electronic endoscope apparatus according to this embodiment includes the light source section 34.
1, the illumination light for field sequential imaging and the illumination light for homogeneous imaging can be switched and irradiated. Further, the signal processing unit 342 is configured to drive the CCD 306 by switching between the frame sequential imaging system and the homogeneous imaging system, and switch the signal processing according to the system. The electronic endoscope apparatus is configured to determine whether the irradiation mode of the light source is for field sequential imaging or homogeneous imaging, and change the AGC detection method according to the determined imaging method. ing. The other configurations and operations similar to those of the nineteenth embodiment are designated by the same reference numerals, description thereof will be omitted, and only different points will be described.

The light source side CPU 343 of the light source unit 341 inputs whether the illumination light is to be selected for field sequential imaging or simultaneous imaging by a switching means provided on a front panel or the like (not shown). It Light source side C
When the illumination light for frame-sequential imaging is selected, the PU 343 moves the RGB filter 344 on the optical axis of the illumination light emitted from the xenon lamp 304 and causes the motor 345 to rotate the filter 344. Three
Control 46.

When the illumination light for simultaneous image pickup is selected, the drive circuit 346 is controlled so that the RGB filter 344 is moved away from the optical axis and the rotation of the motor 345 is stopped.

The illumination light is incident on the light guide 305 and is emitted toward the subject from the front surface of the endoscope.
The CCD 306 arranged at the tip of the endoscope photoelectrically converts this reflected light into an electric signal.

Inside the signal processing unit 342, a frame sequential CCD drive circuit 347 for driving the CCD 306 for frame sequential image pickup and a simultaneous CCD drive circuit 348 for driving the CCD 306 for simultaneous image pickup are provided. There is.

In the signal processing unit 342, the GCA
A frame sequential signal processing unit 350 and a simultaneous signal processing unit 351 are provided side by side in the subsequent stage of the circuit 349. These two
The CCD drive circuits 347 and 348 and the signal processing circuits 350 and 351 of the system are selected by the switches 353 and 354 according to the illumination light currently being emitted by the illumination light determination circuit 352 provided inside the light source 341. It is supposed to be done.

The electric signal read from the CCD 306 is sent to the CDS 30 via the cable 308 in the endoscope.
It is input to the GCA 349 via 9. The CDS output is
Auto gain control is performed by the GCA 349 so that the level is set, and the signal is output to an output device such as a monitor through a signal processing unit corresponding to each imaging method.

The GCA circuit 349 comprises the gain control amplifier 311 and a GCA control section 355 for controlling the gain of the amplifier 311.

Next, the operation of the GCA control unit 355 which controls the AGC operation will be described.

When field-sequential imaging is selected for the illumination light of the light source unit 341, the output of the CCD 306 is, for example, R.G.
It is assumed that they are sent in the field cycle in the order of B, R ... From this, the control voltage of the GCA 311 is determined based on the value obtained by integrating only the G video signal component in the CDS output.

The B signal component and the R signal component may be used instead of the G signal component. Further, instead of only one type of signal component, a plurality of signal components may be integrated and combined, for example, a combination of G component and R component. Alternatively, the R, G, and B signals that are sequentially output are integrated, and the integrated value of the luminance component Y obtained by multiplying and multiplying the multipliers is obtained, and this value is used to determine the GCA control voltage. Is also good.

Next, when the simultaneous imaging type is selected as the illumination light, the CDS output is integrated to determine the GCA control voltage. Alternatively, it is also possible to extract the luminance component Y included in the signal and use it.

FIG. 74 is a block diagram showing a configuration example of the GCA control unit 355.

When the illumination light is of the field-sequential imaging system, the CD
Signals sent to the S output in the order of R, G, B ... Are switched to the three LPF / hold circuits 358 by switching the switch 357 by the switching signal generation circuit 356. The signals held by the three LPF / hold circuits 358 are multiplied by the coefficients by the three multipliers 359 and then added by the adder 360 to obtain the integrated luminance signal Y, which can be obtained. It is the control voltage of GCA.

The switching signal generation circuit 356 controls opening / closing of the switch 357 according to the illumination light discrimination output of the illumination light discrimination circuit 352.

By the way, when using only the G component,
This is possible by changing the switching of the switch 357.

When the illumination light is of the simultaneous image pickup system, the control voltage of the GCA can be taken out by fixing the switch 357 at only one place at all times.

In the present embodiment, the AGC detection method on the processor side is automatically optimized according to the illumination light mode of the light source, so that an electronic endoscope with good operability freed from complicated setting is provided. Can be provided.

75 to 78 relate to the twenty-third embodiment of the present invention, and FIG. 75 is a schematic configuration diagram of the electronic endoscope apparatus, FIG.
6 is a block diagram showing the filter arrangement of the rotary filter, FIG.
Is a block diagram relating to speed detection of the rotary filter, and FIG. 78 is C
It is explanatory drawing regarding the reading of CD, and the control of memory.

The electronic endoscope apparatus of this embodiment shown in FIG. 75 illuminates a subject with field sequential illumination light through an electronic endoscope 371 having a light guide 369 and a CCD 370 and the light guide 369. A light source unit 372 for controlling and CC
The signal processing unit 373 drives the D370 and processes the obtained image pickup signal to output a video signal.

The light source section 372 has a lamp 374,
A rotary filter 375 that separates the light emitted from the lamp 374 into time-series color illumination light, a motor 376 that rotates the rotary filter 375, and a rotary filter rotation speed determination circuit 377 that detects the rotation speed of the rotary filter 375. Have

The CCD 370 is the C of the signal processing unit 373.
Driven by the CD drive circuit 378, the subject image is converted into an image pickup signal. The output of the CCD 370 is the signal processing unit 37.
After being A / D converted by the A / D converter 379 of No. 3, it is synchronized by the memory 380, and is D / A converted by the D / A converter 381.
It is converted and output as a video signal.

Rotation filter rotation speed discrimination circuit 377
Is supplied to the memory control circuit 382 for controlling the writing / reading of the memory 380 and the CCD drive circuit 378.

The light dispersed into each color through the rotary filter 375 is applied to the subject through the light guide 369, and the reflected light is imaged by the CCD 370.

76 (a) to 76 (c) show an example of the structure of the rotary filter 375. As shown in FIG. For example, FIG.
In the case of a filter in which R, G, and B shown in (a) are arranged in order, the CCD is arranged at the timing shown in FIG. 78 (a).
The CCD driving circuit 378 drives the CCD 370 so as to read the image pickup signal from the CCD 370. The image pickup signal read from the CCD 370 is A / D converted and stored in the memory 3
The time series R, G, B data is synchronized by 80, and the R, G, B data is D / A converted to obtain and output a video output.

Similarly, as shown in FIG. 76 (b), R, R, G,
In the case of a filter in which G, B, and B are arranged, FIG. 78 (b)
The CCD 370 is driven and read at the timing shown in
It is synchronized by the memory 380. Further, in the case of the filter in which the shielding portion is arranged between R, G, and B shown in FIG. 76 (c), the CCD 370 is executed at the timing shown in FIG.
Are read out and synchronized by the memory 380.
Incidentally, in the case of the rotary filter of FIG.
The timing shown in (d) may be used.

Here, it is assumed that an image is normally picked up at a rotation cycle of 20 Hz. When the screen becomes dark and normal imaging cannot be performed, the rotation cycle is slowed down to 10 Hz and 5 Hz for imaging. Conversely, when the image is too bright and the image is saturated, 30 Hz and 40 Hz and reading from the CCD 370 is performed. The rotation cycle is increased up to an appropriate speed for imaging.

Here, as an example of determining the rotation speed of the rotation filter 375, a plurality of rotation speed detection marks 383 are provided on the outer circumference or the inner circumference of the rotation filter as shown in FIGS. 77 (a) and 77 (b). The mark 383 is read by the rotation filter rotation speed determination circuit 377, and the CC
The D drive circuit 378 and the memory control circuit 382 are controlled.

Rotation filter rotation speed discrimination circuit 377
Specifically, the reading can be detected by the difference in the amount of reflected light between the mark 383 and a portion where the mark 383 is not applied.

As described above, in the present embodiment, even when the rotation speeds of the rotary filters are different, the rotation speed is detected and C
Since the CD drive and the writing / reading of the memory are controlled, a normal image can be obtained even when the rotation speed of the rotation filter is different.

79 to 82 relate to the twenty-fourth embodiment of the present invention, and FIG. 79 is a schematic block diagram of an electronic endoscope apparatus, FIG.
81 is a block diagram showing a filter opening of the rotary filter, FIG.
Is a configuration diagram relating to aperture ratio detection of the rotary filter, and FIG. 82 is an explanatory diagram relating to CCD reading and memory control.

The electronic endoscope apparatus of the present embodiment discriminates the aperture ratio of the rotary filter of the light source, and according to the discrimination result, C
It is configured to change the drive of the CD and the control of the memory. Other than that, the same components and operations as those of the 23rd embodiment are designated by the same reference numerals, description thereof will be omitted, and only different points will be described.

The light source unit 372 of this embodiment has a rotary filter aperture discriminating circuit 385 instead of the rotary filter speed discriminating circuit 377 of the 23rd embodiment.

The light split into each color through the rotary filter 375 is applied to the subject through the light guide 369, and the reflected light is imaged by the CCD 370.

For example, in the case of the filter shown in FIG. 80 (a) in which the shielding portion is arranged between R, G and B, FIG.
At the timing shown in (c), the CCD driving circuit 378 causes the CCD to read the image pickup signal from the CCD 370.
Drive 370. The image pickup signal read from the CCD 370 is A / D-converted, and time-series R, G, B data is synchronized by the memory 380, and the R, G, B data is D / A-converted to produce an image. Output is being output.

Similarly, as shown in FIG. 80 (b), R, R, G,
In the case of a filter in which G, B, and B are arranged, FIG.
The CCD 370 is driven and read at the timing shown in (b), and is synchronized by the memory 380. Incidentally, FIG.
In the case of the rotary filter of (a), the timing shown in FIG. 82 (c) may be used.

As an example of the structure for determining the aperture ratio of the rotary filter, as shown in FIGS. 81 (a) and 81 (b), a bar code is applied to the outer circumference or the inner circumference of the rotary filter 375,
This barcode is read and determined by the rotary filter aperture determination circuit 385. As a result, the driving of the CCD and the writing / reading of the memory are properly controlled.

As described above, the aperture ratio of the rotary filter is discriminated, and the driving of the CCD and the control of the memory are automatically controlled. Therefore, even if the filters having different aperture ratios of the rotary filter are used, there is no color mixture and the colors are appropriate. You can get a good image.

Although an example in which a bar code is marked for discrimination is shown, it may be discriminated by driving as shown in FIG. 82 (b) and detecting from the CCD output whether or not there is a light shielding portion.

FIG. 83 is a schematic block diagram of an electronic endoscope apparatus according to the 25th embodiment of the present invention.

The electronic endoscope apparatus of this embodiment shown in FIG. 83 has an electronic endoscope 403 having a light guide 401 and a CCD 402 having a color mosaic filter (not shown) arranged on the image pickup surface, and the light guide 401. It has a light source unit 405 having a lamp 404 for irradiating the subject with white illumination light via the, and a signal processing unit 406 for driving the CCD 402 and processing the obtained image pickup signal to output a video signal.

The electronic endoscope device detects from the output of the CCD whether the connected light source has a light quantity adjusting means, and when the detection result is a light source without the light quantity adjusting means, the CCD shutter is used. The drive mode of the CCD is changed so as to adjust the light.

The light from the light source unit 405 which does not have the light control function is guided by the light guide 401 and applied to the subject.
The reflected light is received by the CCD 402 and imaged. C
The output signal of the CD 402 is driven by the CCD drive circuit 407, processed by the video signal processing circuit 408, and output as a video signal.

On the other hand, in the dimming detection circuit 409, the CCD
The dimming control circuit 410 detects the input signal level from the output.
Supply to. In response to this, the dimming control circuit 410 sends a dimming control signal to the light source unit 405 to control the light source unit 405. However, since the light source unit 405 does not have a dimming function, the amount of light from the light source is not controlled, so that the CCD output does not change in signal level according to dimming control. As a result, the dimming control circuit 410 determines that the light source does not have the dimming function, and instructs the shutter control circuit 411 to switch the drive mode. The CCD drive circuit 407 controls the shutter time of the CCD 402 and adjusts the exposure amount of the CCD 402 to obtain proper light control and obtain a normal image.

In this embodiment, a dimming control signal is given to the light source, and it is judged whether or not the light amount changes by the CCD output.
When it is determined that the light source does not have the dimming function, the exposure amount is controlled by the CCD shutter. Therefore, in this embodiment, even when a light source having no dimming function is connected,
You can get a normal image.

FIG. 84 is a schematic block diagram of an electronic endoscope apparatus according to the 26th embodiment of the present invention.

The electronic endoscope apparatus of the present embodiment shown in FIG. 84 has a light source section 413 in which a diaphragm 412 as a light quantity adjusting means is added to the light source section 405 of the 25th embodiment. Further, the aperture amount of the aperture 412 is controlled by the dimming control circuit 414 of the signal processing unit 406. Further, in the electronic endoscope apparatus of the present embodiment, the dimming control circuit 414 detects that transillumination has occurred, and the shutter control circuit 4 responds accordingly.
It is configured to switch to dimming by a CCD shutter via 15. The other configurations and operations similar to those of the twenty-fifth embodiment are designated by the same reference numerals, and description thereof will be omitted.

Light from the light source unit 413 is emitted from the light guide 4
It is guided by 01 and illuminates the subject, and the reflected light is CCD
The light is received and imaged at 402. CCD402 is CCD
It is driven by the drive circuit 407 to capture a subject image.

On the other hand, in the dimming detection circuit 409, the CCD
The signal level is detected from the output and supplied to the dimming control circuit 414. In response to this, the dimming control circuit 414 sends a control signal to the aperture 412 of the light source in order to control the aperture 412 of the light source.
Supply to. However, at the time of transillumination, the light source unit 413 is forced to open the diaphragm 412, so that dimming control cannot be performed. Therefore, the light source unit 41
In response to the transillumination signal from the light source 3, the dimming control circuit 413 instructs the shutter control circuit 415 to switch, and the CCD 402 controls the exposure amount according to the shutter time. As described above, since the exposure amount is controlled by the CCD shutter during transillumination, a normal image can be obtained.

In the present embodiment, the dimming control is switched by the transillumination signal, but the dimming control circuit 414 determines whether or not there is a reaction, so that the switching can be performed regardless of the transillumination signal. Also good.

In this embodiment, since transillumination is detected and the light is switched to the dimming by the CCD shutter, a normal image can be obtained without saturation of the image. FIGS. 85 to 88 are the 27th of the present invention. FIG. 85 is a schematic configuration diagram of an electronic endoscope apparatus according to an embodiment, FIG. 86 is a configuration diagram showing a color array of a rotary filter, FIG. 87 is a configuration diagram relating to detection of a color array of a rotary filter, and FIG. 88 is a CCD. It is explanatory drawing regarding read-out and memory control.

The electronic endoscope apparatus of this embodiment shown in FIG. 85 has a structure in which the color arrangement of the rotary filter is discriminated and the driving of the CCD and the control of the memory are changed according to the discrimination result. Other configurations and operations similar to those of the twenty-third embodiment are designated by the same reference numerals, description thereof will be omitted, and
Only the different points will be described.

The light source section 421 of the present embodiment has a rotary filter color arrangement discriminating circuit 422 instead of the rotary filter speed discriminating circuit 377 of the 23rd embodiment.

The light split into each color through the rotary filter 375 is applied to the subject through the light guide 369, and the reflected light is imaged by the CCD 370.

FIGS. 86 (a) to 86 (c) show an example of the configuration of the rotary filter 375. For example, FIG.
In the case of the filter arranged in order of R, G, B, R, G, B shown in (a), as shown in FIG.
The CCD driving circuit 378 causes the CCD 3 to read the image pickup signal from the CCD 370 in the order of G, B, R, G, B.
Drive 70. The image pickup signal read from the CCD 370 is A / D-converted, and time-series R, G, B data is synchronized by the memory 380, and the R, G, B data is D / A-converted to produce an image. Output is being output.

Similarly, as shown in FIG. 86 (b), R, R, G,
In the case of a filter in which G, B, and B are arranged, FIG. 88 (b)
CCD 370 in the order of R, R, G, G, B, B, ...
Are read out and synchronized by the memory 380.
Also, in the case of the filter in which the shielding portion is arranged between R, G, and B shown in FIG. 86 (c), R, G, and B are intermittently provided during the period in which the shielding portion shown in FIG. 88 (c) is arranged. CCD in order of B
The 370 is driven and read out, and the memory 380 synchronizes them. In the case of the rotary filter shown in FIG. 86 (b),
The timing shown in FIG. 88 (d) may be used.

As an example of the structure for discriminating the color arrangement of the rotary filter 375, as shown in FIGS. 84 (a) and 84 (b), a bar code is applied to the outer circumference or the inner circumference of the rotary filter 375, and this bar code is used. The rotary filter color array discrimination circuit 422 reads and discriminates. By this, CC
The driving of D and the writing / reading of the memory are properly controlled.

As described above, in this embodiment, the color arrangement of the rotary filter is discriminated, and the driving of the CCD and the control of the memory are automatically controlled. Therefore, filters having different color arrangements of the rotary filter are used. Also, it is possible to obtain a proper image without color mixture.

89 to 92 relate to the twenty-eighth embodiment of the present invention, FIG. 89 is a schematic block diagram of an electronic endoscope apparatus without a rotary filter, and FIG. 90 is a schematic view of an electronic endoscope apparatus having a rotary filter. Block diagram, FIG. 91 is a block diagram of the rotary filter,
FIG. 92 is an explanatory diagram relating to the reading of the CCD and the control of the memory.

The electronic endoscope apparatus of the present embodiment discriminates the color arrangement of the rotary filter of the light source, and according to the discrimination result, C
It is configured to change the drive of the CD and the control of the memory. Other than that, the same components and operations as those of the 23rd embodiment are designated by the same reference numerals, description thereof will be omitted, and only different points will be described.

The electronic endoscope apparatus of this embodiment shown in FIGS. 89 and 90 is an apparatus in which the white light illumination type light source section and the field sequential light illumination type light source section are replaceable.

The electronic endoscope apparatus is configured to discriminate whether the light source is the light source for field sequential illumination light or the light source for white light illumination, and optimally change the driving of the CCD or the like according to the discrimination result. There is.

The electronic endoscope apparatus of this embodiment shown in FIG. 90 irradiates the subject with field-sequential illumination light through the electronic endoscope 433 having the light guide 431 and the CCD 432, and the light guide 431. A light source unit 434 for controlling the CC
The signal processing unit 435 drives the D 431 and processes the obtained image pickup signal to output a video signal.

The light source section 434 shown in FIG.
36, a rotary filter 437 for separating the light emitted from the lamp 436 into time-series color illumination light, and the rotary filter 43.
Motor 438 for rotating 7 and rotation filter rotation presence / absence determination circuit 43 for detecting presence / absence of rotation filter 437.
9 and 9.

The light dispersed into each color through the rotary filter 432 is applied to the subject through the light guide 431, and the reflected light is received by the CCD 432 and imaged.

The CCD 432 is driven by the CCD drive circuit 440 of the signal processing unit 435 to convert the subject image into an electric signal. The output of the CCD 432 is the signal processing unit 4
After being A / D converted by the A / D converter 441 of 35, they are synchronized by the memory 442 and D / A converted by the D / A converter 443.
A-converted and output as a video signal.

The rotation filter rotation / non-discrimination circuit 43.
The discrimination signal No. 9 is supplied to the memory control circuit 444 which controls writing / reading of the memory 442 and the CCD drive circuit 440.

On the other hand, the electronic endoscope apparatus shown in FIG. 89 has a light guide 431 and an electronic endoscope 453 having a CCD 452 having a color mosaic filter (not shown) arranged on the image pickup surface, and the light guide 431. Light source unit 45 having a lamp 436 for irradiating the subject with white illumination light and provided with the rotary filter presence / absence discrimination circuit 439.
5 and a signal processing unit 456 for driving the CCD 452, processing the obtained image pickup signal and outputting a video signal.

The white illumination light from the light source unit 455 is guided by the light guide 431 and illuminates the subject, and the reflected light is received by the CCD 452 and imaged. CCD4
Reference numeral 52 is driven by the CCD drive circuit 440 of the signal processing unit 456 to convert the subject image into an image pickup signal. CCD4
The output of 52 is the A / D converter 441 of the signal processing unit 456.
After being A / D converted by, the signal processing circuit 457 synchronizes the signals, and the D / A converter 443 performs D / A conversion to output a video signal.

Rotation filter rotation / non-discrimination circuit 43
The discrimination signal 9 is supplied to the CCD drive circuit 440.

As shown in FIG. 89, when the light source unit is of the white light irradiation type, the light of the lamp 436 is directly illuminated through the light guide 431 and the reflected light is imaged. If you want to capture images with less blurring, use the CCD 45 as shown in Fig. 92 (a).
2 is driven to obtain the frame signal at half the cycle. When it is desired to maximize the dynamic range, the same field as shown in FIG. 92B is read twice and added. Alternatively, when it is desired to operate the S / N well, as shown in FIG. 92C, the S / N is driven as usual to read the electric signal.

The electric signal is converted into a digital signal by the A / D converter 441, and then undergoes signal processing to undergo D / D conversion.
It is A-converted and output as a video output.

As shown in FIG. 90, when the light source section is of the field sequential light irradiation system, the light from the lamp 436 is R, R shown in FIG.
The light is separated by the rotary filter 437 in which the shielding portion is arranged between the G and B filters, passes through the light guide 431, is irradiated to the subject, and the reflected light is imaged by the CCD 432.

Here, when the CCD 432 is for frame transfer (transfer), it is driven as shown in FIG. 92D, and when the CCD 432 is for interline transfer, it is as shown in FIG.
It drives like (e) and an electric signal is read from CCD432. The electric signal is converted into a digital signal by the A / D converter 441, and then synchronized by the memory 442, D / A converted, and output as a video output. CCD
The change of the driving method of 439 is controlled by the rotation filter presence / absence determining circuit 439 provided in the light source section. When the filter is present, the field sequential irradiation method is driven as shown in FIGS. In this case, the white light irradiation method can be switched to drive as shown in FIGS. 92 (a), (b) and (c).

As described above, since it is determined whether the light source is the field-sequential type or the white light type and the drive of the CCD is controlled, whether the light source is the field-sequential type or the white light type,
The optimum driving method can be selected.

Incidentally, the rotation filter presence / absence determining circuit is provided in the light source section to discriminate between the field sequential type and the white light type.
In the white light type, first, as shown in FIG. 92 (a), the image is driven and imaged, and it is detected that the read electrical signal is changed by the rotary filter in the odd field and the even field, and the It may be configured to detect the presence or absence. Also with this configuration, it is possible to discriminate between the field sequential type and the white light type. Alternatively, the same field may be used for comparison by the CCD drive shown in FIG.

In each of the above embodiments, the image pickup means is not limited to the one provided in the endoscope, but may be an external TV camera connected to the eyepiece of the optical fiber endoscope.

[0433]

The electronic endoscope apparatus of the present invention has the effect that the optimum signal processing operation of the image pickup signal can be changed in accordance with the information regarding the illumination light generating means.

[Brief description of drawings]

FIG. 1 is an overall configuration diagram of an electronic endoscope apparatus.

FIG. 2 is a block diagram of a light source and signal processing of the device.

FIG. 3 to FIG. 6 relate to the first embodiment and FIG. 3 is an overall configuration diagram of an electronic endoscope apparatus.

FIG. 4 is a block diagram showing a configuration example regarding transmission of a light source determination signal.

5 is a waveform diagram relating to the operation of the configuration shown in FIG.

FIG. 6 is a block diagram showing a configuration example of a video signal processing circuit.

7 to 9 relate to the second embodiment, and FIG. 7 is an overall configuration diagram of an electronic endoscope apparatus.

FIG. 8 is a block diagram of a white balance circuit.

9 is a block diagram of a white balance circuit different from FIG.

FIG. 10 is an overall configuration diagram of an electronic endoscope apparatus according to a third embodiment.

11 and 12 relate to a fourth embodiment, and FIG.
1 is an overall configuration diagram of the electronic endoscope apparatus.

FIG. 12 is a block diagram showing a configuration example of a video signal processing circuit.

13 to 17 relate to a fifth embodiment, and FIG. 13 is an overall configuration diagram of an electronic endoscope apparatus.

FIG. 14 is a configuration diagram of a rotary filter.

FIG. 15 is a block diagram showing a configuration example of a video signal processing circuit.

FIG. 16 is an explanatory diagram of chromaticity conversion.

FIG. 17 is a flowchart regarding changing / setting of matrix coefficients.

18 to 22 relate to the sixth embodiment, and FIG. 18 is an overall configuration diagram of an electronic endoscope apparatus.

FIG. 19 is a block diagram showing a configuration example of a video signal processing circuit.

FIG. 20 is an explanatory diagram of chromaticity conversion.

FIG. 21 is a characteristic diagram of a normal light and an emergency light.

FIG. 22 is a flowchart relating to changing / setting of matrix coefficients.

23 to 26 relate to the seventh embodiment, and FIG. 23 is an overall configuration diagram of an electronic endoscope apparatus.

FIG. 24 is a block diagram showing a configuration example of a video signal processing circuit.

FIG. 25 is a block diagram showing another configuration example of the video signal processing circuit.

FIG. 26 is a block diagram showing another configuration example of the video signal processing circuit.

27 and 28 relate to an eighth embodiment and are different from FIG.
7 is an overall configuration diagram of an electronic endoscope apparatus.

FIG. 28 is a block diagram showing a configuration example of a video signal processing circuit.

29 to 34 relate to the ninth embodiment, and FIG. 29 is an overall configuration diagram of an electronic endoscope apparatus.

FIG. 30 is a circuit diagram of a first detection circuit compatible with a frame-sequential imaging method.

FIG. 31 is a circuit diagram of a second detection circuit compatible with the simultaneous method.

FIG. 32 is a circuit diagram of a detection circuit capable of supporting a plurality of illumination modes.

FIG. 33 is a block diagram of a first signal processing circuit.

FIG. 34 is a block diagram of a second signal processing circuit.

FIG. 35 is an overall configuration diagram of an electronic endoscope apparatus according to a tenth embodiment.

36 to 38 relate to the eleventh embodiment,
FIG. 36 is a block diagram showing a schematic configuration of the electronic endoscope apparatus.

FIG. 37 is a chart showing a setting relationship between AGC gain and contour enhancement level.

FIG. 38 is an explanatory diagram regarding switching of the edge enhancement level.

39 to 41 relate to a twelfth embodiment,
FIG. 39 is a block diagram showing the configuration of the electronic endoscope apparatus.

FIG. 40 is an explanatory diagram regarding switching of color tone adjustment levels.

FIG. 41 is a chart showing the relationship between color tone adjustment settings and instruction values.

42 to 45 relate to a thirteenth embodiment,
FIG. 42 is a block diagram showing a schematic configuration of the electronic endoscope apparatus.

FIG. 43 is a block diagram of a video signal processing circuit.

FIG. 44 is a block diagram of a simultaneous signal processing circuit.

FIG. 45 is a block diagram of a frame sequential signal processing circuit.

46 to 48 relate to a fourteenth embodiment,
FIG. 46 is a block diagram showing the configuration of the signal processing unit of the electronic endoscope apparatus.

FIG. 47 is a configuration diagram of a light source unit.

FIG. 48 is a flowchart relating to white balance adjustment.

FIG. 49 is a flowchart of white balance adjustment according to the fifteenth embodiment.

50 to 53 relate to a sixteenth embodiment,
FIG. 50 is a block diagram of a white balance detection circuit at the time of single-plate color imaging.

FIG. 51 is a block diagram of a white balance detection circuit at the time of frame sequential imaging.

52 is a timing chart of the circuit shown in FIG. 50.

53 is a timing chart of the circuit shown in FIG. 51.

54 to 58 relate to a seventeenth embodiment,
FIG. 54 is a configuration diagram of an optical system in the light source unit.

FIG. 55 is an explanatory view showing the shape of the diaphragm blade and the positional relationship with the optical axis.

FIG. 56 is a correlation diagram between the aperture of the diaphragm and each color in the CCD output.

FIG. 57 is a flowchart of timer interrupt.

FIG. 58 is a flowchart for obtaining a white balance correction value.

59 to 63 relate to the eighteenth embodiment,
FIG. 59 is a block diagram of a light source unit.

FIG. 60 is a flowchart of white balance setting in special light mode.

FIG. 61 is a block diagram showing a configuration of an optical system of a light source section.

FIG. 62 is a perspective view showing the configuration of single-wavelength illumination.

FIG. 63 is a perspective view showing a configuration of three-wavelength illumination.

64 to 69 relate to a nineteenth embodiment,
FIG. 64 is a schematic configuration diagram of an electronic endoscope.

FIG. 65 is an explanatory diagram of a monitor screen.

66 is a waveform diagram of a video signal of the A scan line on the screen shown in FIG. 65.

FIG. 67 is an explanatory diagram of AGC detection.

FIG. 68 is a circuit diagram showing a configuration of a GCA control unit.

FIG. 69 is a circuit diagram showing another configuration of the GCA control unit.

70 and 71 relate to the twentieth embodiment, and FIG. 70 is a schematic configuration diagram of an electronic endoscope.

71 is a timing chart showing the operation of the apparatus shown in FIG.

72 is a schematic configuration diagram of an electronic endoscope apparatus according to a twenty-first embodiment. FIG.

73 and 74 relate to the twenty-second embodiment, and FIG. 73 is a schematic configuration diagram of the electronic endoscope apparatus.

FIG. 74 is a block diagram showing a configuration example of a GCA control unit.

75 to 78 relate to the twenty-third embodiment,
FIG. 75 is a schematic configuration diagram of the electronic endoscope apparatus.

FIG. 76 is a configuration diagram showing a filter arrangement of a rotary filter.

77 is a configuration diagram relating to speed detection of the rotary filter. FIG.

FIG. 78 is an explanatory diagram relating to CCD reading and memory control.

79 to 82 relate to the twenty-fourth embodiment,
FIG. 79 is a schematic configuration diagram of the electronic endoscope apparatus.

FIG. 80 is a configuration diagram showing a filter opening of a rotary filter.

FIG. 81 is a configuration diagram relating to aperture ratio detection of a rotary filter.

FIG. 82 is an explanatory diagram relating to CCD reading and memory control.

FIG. 83 is a schematic configuration diagram of an electronic endoscope apparatus according to a twenty-fifth embodiment.

FIG. 84 is a schematic configuration diagram of an electronic endoscope apparatus according to a 26th embodiment.

85 to 88 relate to the twenty-seventh embodiment,
FIG. 85 is a schematic configuration diagram of the electronic endoscope apparatus.

FIG. 86 is a configuration diagram showing a color arrangement of a rotary filter.

FIG. 87 is a configuration diagram regarding detection of a color array of a rotary filter.

FIG. 88 is an explanatory diagram relating to CCD reading and memory control.

89 to 92 relate to the twenty-eighth embodiment,
FIG. 89 is a schematic configuration diagram of an electronic endoscope apparatus without a rotary filter.

FIG. 90 is a schematic configuration diagram of an electronic endoscope apparatus having a rotary filter.

FIG. 91 is a configuration diagram of a rotary filter.

FIG. 92 is an explanatory diagram relating to CCD reading and memory control.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Electronic endoscope device 2 ... Electronic endoscope 3 ... Light source device 4 ... Processor 9 ... Video signal processing circuit 13 ... Solid-state image sensor 18 ... Discrimination signal generator 19 ... Discrimination circuit 26 ... Preprocessing circuit 27 ... White balance Circuit 28 ... Matrix circuit

─────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission date] September 2, 1993

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0028

[Correction method] Change

[Correction content]

As described above, since an accurate examination cannot be performed under an emergency light, it is usually necessary to ensure the safety of the patient .
Only the removal of the endoscope was done.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yuki Terakubo 2-43-2 Hatagaya, Shibuya-ku, Tokyo Olympus Optical Co., Ltd. (72) Inventor Yasuo Komatsu 2-43-2 Hatagaya, Shibuya-ku, Tokyo Olympus Optical Co., Ltd.

Claims (1)

[Claims] 1. An illumination light generation means for generating illumination light for illuminating a subject, a signal processing means for signal-processing an image pickup signal obtained by capturing an image of a subject illuminated by the illumination light, and the illumination light. Information supplying means for supplying illumination light generating means information on the generating means, and signal processing operation changing means for changing the signal processing operation of the signal processing means based on the illumination light generating means information supplied by the information supplying means. An electronic endoscopic device characterized by being provided.