JP2996373B2 - Electronic endoscope device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an 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, it is possible to observe an organ in the body cavity, and if necessary,
2. Description of the Related Art An endoscope capable of performing various medical treatments using a treatment tool inserted into a treatment tool channel is widely used.

[0003] Boilers, gas turbine engines,
2. Description of the Related Art Industrial endoscopes are widely used for observing and inspecting internal scratches and corrosion of pipes of chemical plants and the bodies of automobile engines and the like.

Further, various types of electronic endoscopes using a solid-state imaging device such as a charge-coupled device (CCD) as an imaging means have been used.

FIG. 1 shows an example of the configuration of an electronic endoscope apparatus using an electronic endoscope 81. As shown in FIG. This electronic endoscope 8
1 has an elongated and flexible insertion portion 82, for example, 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 a rear end of the operation section 83, and a connector 85 is provided at a distal end of the cable 84. The electronic endoscope 81 is, via the connector 85, a light source device as illumination light generating means and a video processor 8 having a signal processing circuit built therein.
6 is connected. Further, a monitor 87 is connected to the video processor 86.

At the distal end of the insertion portion 82, a rigid distal end 89 and a bendable bending portion 90 adjacent to the rear side of the distal end 89 are sequentially provided. The endoscope 81 is provided with a bending operation section knob 9 provided on the operation section 83.
By rotating the knob 1, the bending portion 90 can be bent in the left-right direction or the up-down direction.
The operation section 83 has an insertion port 92 communicating with a treatment instrument channel (not shown) provided in the insertion section 82.
Is provided.

As shown in FIG. 2, a light guide 94 for transmitting illumination light is inserted into an insertion portion 82 of the electronic endoscope 81. The distal end surface of the light guide 94 is arranged at the distal end 89 of the insertion section 82 so that illumination light can be emitted from the distal end 89. The light guide 94 has an incident end inserted into a universal cord 84 and connected to a connector 85. Further, an objective lens system 95 is provided at the distal end portion 89, and a solid-state imaging device 96 such as a CCD is disposed at an image forming position of the objective lens system 95. The solid-state imaging device 96 has sensitivity in a wide wavelength range from the ultraviolet region to the infrared region including the visible region. The solid-state imaging device 96 includes a signal line 7.
The signal lines 71 and 72 are inserted into the insertion portion 82 and the universal cord 84 and connected to the connector 85.

On the other hand, a lamp 73 is provided in the video processor 86 as an illumination light source that emits light in a wide band 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, the strobe lamp, and the halogen lamp emit not only visible light but also a large amount of ultraviolet light and infrared light. This lamp 73
Are supplied with power by a 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 distal end portion 89 via the light guide 94, emitted from the distal end portion 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 imaging device 96 by the objective lens system 95, and is photoelectrically converted. A drive pulse from a 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 reads out a video signal by the driving pulse and transfers the video signal.

The video signal read from the solid-state image pickup device 96 is input 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 a process circuit 75, subjected to signal processing such as γ correction and white balance, output as R, G, and B color signals, and input to an encoder 76. It has become. The encoder 76 converts the R, G, B color signals into N
A TSC composite signal is output.

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

The R, G, B color signals or N
The TSC composite signal is input to a color monitor 87, and the observation portion is displayed in color by the color monitor 87.

[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 disadvantages can be considered.
Representative examples of endoscope lamps include the above-described xenon (Xe) lamp and halogen lamp. The radiant energy distribution differs between the xenon lamp and the halogen lamp, and the color temperature also differs by about 2000K. When the color temperatures are so different, even if the white balance is adjusted and the color reproduction of only white color is adjusted, the color reproduction of other colors deteriorates. Generally, a xenon lamp is used as a normal lamp, and a halogen lamp is used as an emergency lamp.

The illumination (imaging) system, which is the type of the light source as the illumination light generating means information, is different between different systems such as a frame sequential system or a single-plate color system (hereinafter sometimes referred to as a simultaneous system). However, the signal processing method must be changed, and the conventional example cannot cope with the problem.

[0015] Among the fields of use of endoscopes, medical endoscopes have a reddish-colored relatively dark color because the object is the inner wall of the body or the like. Therefore, when the distance between the distal end of the endoscope and the subject increases, the illumination light emitted from the light guide is reflected on the inner wall, and then more often irradiates the subject. For this reason, the color of the subject becomes more red-based color than it actually is. The image is affected by the so-called secondary reflected light.

Further, there is a light source device having three kinds of illumination modes of a field sequential type / single plate color type / optical fiber endoscope, and the mode is set according to the type of the endoscope and the 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 a light source device, a system that can efficiently and correctly set each device and has good operability is desired.

Furthermore, in an electronic endoscope apparatus capable of processing image signals obtained by both the frame sequential method and the simultaneous method, the forms of the signals obtained by the two methods are different. For this reason,
As the signal processing, for example, it is necessary to change a white balance processing operation or the like in accordance with the above method.

Also, according to the difference between the field sequential mode and the simultaneous mode, which are one of the operation states of the light source, the A on the processor side
In GC (auto gain control), it is necessary to change a detection method for generating a signal for controlling a gain.

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

Further, even in the case of a light source device of the field sequential type, if the rotation speed of the rotary filter for separating the illumination light into a plurality of different wavelength ranges changes, color mixing occurs. Also, if the aperture ratio of the optical filter arranged in the rotary filter changes, light leakage occurs, flicker, color mixing, and the like occur. Further, 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.

Some electronic endoscope devices use special light, such as infrared light, for the purpose of, for example, blood flow observation, in addition to imaging using surface-sequential illumination light or white illumination light.

When performing the special light observation, in the signal processing, a color tone suitable for observation cannot always be obtained with the white balance at the time of normal light observation.

Conventionally, the signal processing operation of the processor has not been changed even if the xenon lamp, which is a normal lamp of the light source device, is switched to the halogen lamp, which is an emergency lamp. For this reason, when switching to an emergency light during the inspection, the color suddenly changes, so that it is difficult to make the observation sudden, and the inspection is hindered.

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

Alternatively, the processing has been carried out with the white balance set by a xenon lamp, even though the lit lamp is a halogen lamp. For this reason, the obtained image has become a reddish image.

As described above, under an emergency light, a precise inspection cannot be performed. Therefore, usually, only the endoscope is removed in order to ensure patient safety.

It is necessary to take measures not only for the life and failure of the lamp but also for the decrease in the light amount of the lamp due to aging, in order to obtain a better image. For example, the amount of light of a xenon lamp used in a light source device is inversely proportional to the lighting time. Therefore, before and after the lamp replacement, the light amount of the light source is more than doubled.

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

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

The processor of the electronic endoscope apparatus generally includes:
AGC to keep the level of the signal captured by the CCD constant
It is carried out. However, when the light intensity of the lamp decreases,
When the AGC operates, noise becomes conspicuous. In particular, when the normal light is switched to the emergency light, abnormal color tone becomes noticeable.

As for the operation of the AGC, there is a problem due to the relationship with the stop as a light amount adjusting means of the light source.

For displaying an endoscope 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, an apparatus has been proposed in which one displays a moving image and the other displays a still image.

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

AGC is based on reflected light from a subject.
Although it works to keep the signal level constant, it has the drawbacks described above depending on the state of the aperture and the illumination light source, and the conventional one has individual measures such as the state of the light source device and multiple illumination modes. Did not.

In addition, in the conventional electronic endoscope apparatus, if a light source having no light amount adjusting means is connected instead of a light source having a function of performing automatic light control, the light amount can be appropriately controlled. No normal images could be obtained.

In the conventional electronic endoscope apparatus, when transillumination is performed at the light source, the aperture is opened, the light amount cannot be controlled, and the brightness of the image is saturated.

As described above, unless various measures are taken in accordance with the illumination light generating means information such as the type, operating state, and function of the light source, problems will occur in terms of image quality deterioration and efficiency.

An object of the present invention is to provide an electronic endoscope apparatus capable of changing an optimal signal processing operation of an image signal in accordance with an illumination mode of an illumination light generating unit.

[0039]

In order to achieve the above object, an electronic endoscope apparatus according to a first aspect of the present invention switches between a first illumination mode and a second illumination mode to generate illumination light. Generating means, and signal processing means for processing, based on the illumination light illuminated by the illumination light generating means, an imaging signal including color information of a subject image imaged by the imaging means into a signal that can be displayed on a display means; A white balance circuit that forms a part of signal processing means and outputs a control signal for controlling a white balance of the image signal based on the image signal, and a white balance control signal that is output by the white balance circuit. An illumination mode detecting means for detecting the illumination mode of the illumination light generating means, and the signal processing means according to a detection result of the illumination mode detecting means. A signal processing operation changing means for changing the signal processing function corresponding to the bright mode or the second illumination mode, in which with a.

In the electronic endoscope apparatus according to the second invention, a first illumination mode in which illumination is performed by ordinary light generated by an ordinary light lamp, and a special light observation filter is inserted on an optical path of illumination light. An illumination light generating means for illuminating the subject by switching to a second illumination mode for performing illumination with special light different from the normal light, and an imaging means based on the illumination light illuminated by the illumination light generating means. A signal processing unit that processes an imaging signal including color information of a captured subject image; an illumination mode determination unit that determines the illumination mode of the illumination light generation unit; and a determination result of the illumination mode determination unit. Signal processing operation changing means for changing the signal processing means to a signal processing function corresponding to the first lighting mode or the second lighting mode.

Further, an electronic endoscope according to a third aspect of the present invention includes:
An illumination light generating means for illuminating a subject by switching between a first illumination mode for performing illumination with a normal light lamp and a second illumination mode using an emergency lamp, and an illumination light illuminated by the illumination light generation means. Signal processing means for processing an image signal including color information of a subject image picked up by an image pickup means, illumination mode discrimination means for discriminating the illumination mode of the illumination light generation means, and discrimination by the illumination mode discrimination means. Signal processing operation changing means for changing the signal processing means to a signal processing function corresponding to the first lighting mode or the second lighting mode according to a result.

According to a fourth aspect of the invention, there is provided an electronic endoscope apparatus for switching between a first illumination mode for illuminating a subject with continuous light and a second illumination mode for flash light to generate illumination light. A signal processing unit that processes an imaging signal including color information of a subject image captured by an imaging unit into a signal that can be displayed on a display unit, based on the illumination light illuminated by the illumination light generation unit; and Automatic gain control means for extracting the output image signal under predetermined extraction conditions, amplifying the image signal based on the signal level of the extracted image signal, and determining the illumination mode of the illumination light generating means The extraction condition of the image pickup signal by the automatic gain control means is set in advance according to the first illumination mode in accordance with the result of the determination by the illumination mode determination means. A signal processing operation changing means for changing the second extraction condition set in advance corresponding to the first extracting condition or the second illumination mode which is set, in which with a.

An electronic endoscope apparatus according to a fifth aspect of the present invention includes a first illumination mode for illuminating a subject with illumination light for a frame sequential type and a second illumination mode for illuminating an object with illumination light for a simultaneous type. Illumination light generating means for switching to generate illumination light, based on the illumination light illuminated by the illumination light generating means,
A signal processing unit configured to process an image signal including color information of a subject image captured by an imaging unit into a signal that can be displayed on a display unit, and a part of a white balance circuit provided in the signal processing unit; A white balance detection circuit for detecting a white balance of the imaging signal, an illumination mode detection means for detecting the illumination mode of the illumination light generation means, and the white balance detection circuit according to a detection result of the illumination mode detection means. Signal processing operation changing means for changing to a detection function corresponding to the first illumination mode or the second illumination mode.

According to a sixth aspect of the invention, there is provided an electronic endoscope apparatus comprising: a first illumination mode for irradiating illumination light by rotating a rotation filter for plane sequential illumination at a first rotation speed; An illumination light generating means for illuminating a subject by switching a filter to a second illumination mode in which illumination light is emitted by rotating the filter at a second rotation speed; and imaging based on the illumination light illuminated by the illumination light generation means. A signal processing unit that performs signal processing on an imaging signal including color information of a subject image captured by the unit, an illumination mode detection unit that detects the illumination mode of the illumination light generation unit, and a detection result of the illumination mode detection unit. And a signal processing operation changing means for converting the signal processing means into a signal processing function corresponding to the first lighting mode or the second lighting mode.

An electronic endoscope apparatus according to a seventh aspect of the present invention comprises:
A first illumination mode for illuminating a subject using a first plane-sequential illumination rotation filter having an aperture ratio of, and a subject image using a second plane-sequential illumination rotation filter having a second aperture ratio. An illumination light generating unit for illuminating a subject image by switching to a second illumination mode for illumination; a driving unit for driving an imaging unit for capturing the subject image; and an illumination light illuminated by the illumination light generating unit. A signal processing unit that performs signal processing on an imaging signal including color information of a subject image captured by the imaging unit; an illumination mode determination unit that determines the illumination mode of the illumination light generation unit; and an illumination mode determination unit. A signal processing unit that converts the driving unit and the signal processing unit into a driving condition and a signal processing function corresponding to the first lighting mode or the second lighting mode, respectively, according to the determination result. Those having a changing means.

[0046]

[0047]

[0048]

[0049]

[0050]

[0051]

[0052]

[0053]

Embodiments of the present invention will be described below with reference to the drawings. 3 to 5 relate to a first embodiment of the present invention. FIG. 3 is a diagram showing the overall configuration of an electronic endoscope apparatus, FIG. 4 is a block diagram of a white balance circuit, and FIG. It is a block diagram of a white balance circuit.

The electronic endoscope device 1 shown in FIG. 3 includes an electronic endoscope 2, a light source device 3 as illumination light generating means, a processor 4 as signal processing means, and a monitor (not shown). .

The electronic endoscope 2 has an elongated, for example, flexible insertion portion 5, and a large-diameter operation portion 6 is connected to the rear end of the insertion portion 5. The operating unit has a flexible cable 7 extending laterally, and a connector 8
Is provided. The electronic endoscope 2 is connected to a light source device 3. Also, the electronic endoscope 2
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.
In addition, 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 rigid distal end portion 10 and a bendable portion (not shown) adjacent to the rear end of the distal end portion 10 and capable of bending are provided. Further, the endoscope 2 can bend the bending portion in the left-right direction or the up-down direction by rotating a bending operation portion knob (not shown) provided on the operation portion 6.

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

An objective lens system 12 is provided at the distal end portion 10.
A solid-state imaging device 13 is provided. The solid-state imaging device 13 has sensitivity in a wide wavelength range from the ultraviolet region to the infrared region including the visible region. Signal lines 14 and 15 are connected to the solid-state imaging 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 a wide band of light from ultraviolet light to infrared light. As the lamp 16, for example, a general xenon lamp, a strobe lamp,
A halogen lamp or the like can be used. The xenon lamp, the strobe lamp, and the halogen lamp emit not only visible light but also a large amount of ultraviolet light and infrared light. Lamp 16
Can be selected according to the application.

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

The return light from the observation site due to the illumination light is focused on the solid-state image pickup device 13 by the objective lens system 12 and is photoelectrically converted. A driving pulse from a driving circuit 17 in the processor 4 is applied to the solid-state imaging device 13 via the signal line 14,
Reading and transferring are performed by the driving pulse. The video signal read from the solid-state imaging device 13 is input to the video signal processing circuit 9 via the signal line 15. The video signal processing circuit 9 includes a pre-processing circuit 26, a white balance circuit 27, and a post-processing circuit 30. The video signal processing circuit 9 amplifies a video signal and performs signal processing such as γ correction and white balance. , R, G, B color signals or NTS
The signal is output as a C composite signal.

Here, the white balance operation is performed, for example,
When a white subject is imaged, the output RGB signal values are controlled so as to have the same value.

The output of the white balance circuit 27 is
The type of the light source is input to the determination circuit 29, and the output is input to the post-processing circuit 30.

Then, the R, G, B color signals or N
A TSC composite signal is input to the color monitor, and the observation site is displayed in color by the color monitor.

In the above configuration, the light emitted by the lamp 16 in the light source device 3 passes through the light guide 11
Irradiated toward the observation site from. Light guide 11
The observation site illuminated by the above is imaged on the solid-state imaging device 13 by the objective lens system 12. Solid-state imaging device 1
The image (light) of the observation site formed in 3 is photoelectrically converted, and is read out at a predetermined timing by a drive pulse transmitted from 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.

This video signal is input to a white balance circuit 27 after being subjected to predetermined processing such as color separation and synchronization in a preprocessing circuit 26 of the video signal processing circuit 9. In the white balance circuit 27, for example, when a white image is taken, R
Control is performed so that the levels of the GB color signals match.
For this level adjustment, the white balance circuit 27 uses the output signal of the pre-processing circuit 26 to create a control signal. An example of the configuration of this control is shown in FIGS.

The white balance circuit shown in FIG. 4 has a gain control amplifier (GCA) 31R,
The comparison circuits 32R and 32B compare the levels of the R and B signals output from the input signal G with the levels of the R and B signals output by the comparison circuit 3B.
The gain control amplifier 31 is controlled by the control signals output from the 2R and 32B so that the RGB signal levels match.
The gain of R and 31B is adjusted. This control signal is also output to the determination circuit 29.

The white balance circuit shown in FIG. 5 converts the R and B signals output from the gain control amplifiers 31R and 31B into the input G signal based on the level difference between the input R and B signals and the input G signal when capturing white light. The control signal generation circuits 33R and 33B generate control signals so as to match the levels of the control signals and output the control signals to the gain control amplifiers 31R and 31B. This control signal is also output to the determination circuit 29.

The white balance control signal differs depending on the type of light source. For example, considering a xenon lamp as a reference, when the lamp is changed to halogen, the color temperature of the light source increases, and the energy of the long wavelength component of the light increases. 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 in the case of the xenon lamp. The control signal is input to the determination circuit 29, the type of the light source is determined, and the result is output to the post-processing circuit 30 as a switching signal.

This switching signal causes the post-processing circuit 3
0 switches values such as matrix constants.

As described above, in the first embodiment, the type of the light source is determined based on the control signal for white balance, and the video signal processing is switched based on the result.
Optimal video signal processing can be performed. In this embodiment, it is not necessary to transmit a determination signal from the light source, and the system can be simplified.

In the above description, the processing of the post-processing circuit 30 is merely switched by the switching signal. However, the operation of the pre-processing circuit 26 which does not involve the light source determination may be switched. it can.

In the above embodiment, the white balance and the signal processing have been described with reference to the RGB signals. However, the white balance and the signal processing may be performed using the luminance (Y) and color difference (RY, BY, etc.) signals. Applicable. Although not shown, in the case of the frame sequential method, a plurality of illumination lights having different wavelength ranges are radiated from the lamp 16 of the light source device 3 in time series. This is realized by interposing a rotary filter between the entrance end of the light guide 11 and the lamp 16.

FIGS. 6 to 10 relate to a second embodiment of the present invention. FIG. 6 is an overall configuration diagram of an electronic endoscope apparatus. FIG. 7 is a block diagram showing a configuration example of a video signal processing circuit. 8 is an explanatory diagram of chromaticity conversion, FIG. 9 is a characteristic diagram of a normal light and an emergency light, FIG.
0 is a flowchart relating to the change / setting of the matrix coefficient.

The light source device of this embodiment is configured to switch to an emergency light when a 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 characteristics of the emergency light.

In this embodiment, for example, a xenon lamp is used as the main lamp 16, which is a normal lamp of the light source device 3 shown in FIG. If the main lamp 16 cannot be turned on during inspection for some reason, the lamp control circuit 4
3 is illuminated by the emergency light 44. As the emergency light 44, for example, a halogen lamp is used.

The lamp control circuit 43 informs the discrimination signal generator 18 whether or not the lamp being used has been switched to an emergency light. The determination circuit 19 of the processor 4 shown in FIG. 6 switches the processing operation of the video signal processing circuit 9 according to the determination signal of the determination signal generator 18. In addition, the same configurations and operations as those of the first embodiment are denoted by the same reference numerals, and description thereof is omitted.

In the above configuration, 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 applied to the subject from the distal end of the endoscope. The subject image is formed on the solid-state imaging device 13 by the objective lens 12, converted into an electric signal by the solid-state imaging device 13, transmitted to the processor 4,
The video signal is processed by the video signal processing circuit 9.

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

If the main lamp 16 cannot be turned on during the inspection for some reason, the process goes to step S51.
The emergency light 4 is switched by the lamp controller 43.
Illumination is provided by 4. Since a halogen lamp is used as the emergency light 44, as shown in FIG. 9, the illumination has a lower color temperature than the xenon lamp. In this case, if 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 also proceeds to 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 to notify that it has been switched to the emergency light. In steps S54 and S55, the determination circuit 19 recognizes that the lamp has been switched on the processor 4 side, and changes the processing content of the video signal processing circuit 9 in step S56 and thereafter.

FIG. 7 shows a configuration example of the color conversion means of the video signal processing circuit 9. In the video signal processing circuit 9, when the lamp switching signal is transmitted by the discriminating circuit 19, the coefficient generator 45 sends 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.

An important color for color reproduction of an endoscope image is a red-based color. For example, when a reference red image is taken, the position of the color signal corresponding to the red on the vector scope is shown in FIG.
At the position of D in FIG.

Here, as shown in FIG. 9, the xenon lamp and the halogen lamp have different emission characteristics. 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 prescribed D position, but becomes, for example, the position C in the figure. In this case, the matrix circuit 46 performs steps S56 to S5
As shown in 8, a matrix coefficient for converting the saturation and hue of the signal corresponding to the reference red is selected and set, the coefficient at the position of D is loaded on the vectorscope, and then the signal is converted.

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

In the above description, only one color of the red system is described. However, actually, a plurality of colors are considered, and the matrix constant is determined so that the overall color reproduction is optimal.

In this embodiment, the color conversion circuit is a matrix circuit. However, other color conversion means, for example, a configuration for conversion in a color space may be used. Also, the color conversion means
Using a programmable element such as an LCA, a discriminating circuit 19
May be reconfigured according to the instruction.

In this embodiment, even if the light source is switched from the normal light to the emergency light, a change in an image, particularly, a color change can be reduced.

FIGS. 11 to 14 relate to a third embodiment of the present invention. FIG. 11 is a block diagram showing a schematic configuration of an electronic endoscope apparatus. FIG. 12 is a block diagram of a video signal processing circuit.
3 is a block diagram of a simultaneous signal processing circuit, and FIG. 14 is a block diagram of a frame sequential signal processing circuit.

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

The electronic endoscope apparatus shown in FIG.
66, light source unit 167, processor unit 168
It is composed of

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

In the light source unit 167, there is disposed a rotary filter 176 inserted into and removed from the optical path and rotated by a motor 175. Rotary filter 176
Is controlled by the filter control means 177. That is, the light source unit 167 can switch between two illumination modes, a frame sequential type and a simultaneous type. The setting of the lighting mode is performed by the external panel 1
This is set by a button 78 (not shown) or the like. For the selected mode, the light source 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. At the same time, the light source side CPU 179
Of the rotation filter 176 is sent to the CPU 183 of the processor.

The processor-side CPU 183 which has received the illumination mode information 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, the signal processing is performed by either the frame sequential method or the simultaneous method.

FIG. 12 is 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 based on the determination signal sent from the light source unit 167.

The video signal processing circuit 181 has an AGC1
An A / D converter 184 that inputs the output of the A / D converter 80, a switch 185, a frame sequential signal processing circuit 186, a simultaneous signal processing circuit 187, a switch 188, a matrix circuit 189, and a 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 switches 185 and 188 are interposed before and after the signal processing circuit 186. The switches 185 and 188 can be switched by a control signal corresponding to the illumination mode.

Incidentally, for the frame sequential type and the simultaneous type, usually,
The endoscope shall be replaced. In an endoscope that performs simultaneous imaging, a color mosaic filter is arranged in front of a CCD. On the other hand, an endoscope that performs imaging in a frame sequential manner does not have a color mosaic filter.

The processor-side CPU 183 transmits to the matrix circuit 189 a coefficient for correcting a difference between the color characteristics of the plane sequential rotation filter 176 and the color characteristics of the simultaneous color mosaic filter of the CCD.

FIG. 13 shows a configuration example of the frame sequential signal processing circuit 186.

In the field sequential method, RGB sequential signals are input to the same circuit 186 in a time-series manner.
The black level is adjusted by 92, and thereafter, the white balance is adjusted by a white balance (hereinafter abbreviated as WB) circuit 193. The white balanced signal is
γ correction is performed by the γ correction circuit 194, and RGB is stored in the memory 195.
The sequential signals become R / G / B signals that are synchronized.

FIG. 14 shows a configuration 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 a color separation circuit 196. The luminance signal and the color difference signal are converted to RGB signals by a color processing circuit 198 after the black level is adjusted by a black level adjuster 197. For each signal converted to R / G / B, W.R. The white balance adjustment is performed by the B circuit 199, and the adjusted signals are γ-corrected by the γ correction circuit 200 and output to the matrix circuit 189 via the memory 201.

In this embodiment, it is possible to cope with two systems, a frame sequential system and a simultaneous system, and the switching setting can be automatically and simply performed.

Further, in the present embodiment, the coefficient of the matrix circuit 189 is changed in accordance with the mode of the frame sequential / simultaneous mode, and it is possible to cope with the difference between the characteristics of the rotation filter and the color mosaic filter. That is, even if the color reproducibility is in a different mode, an image which can be maintained uniformly and can be easily observed can be provided.

FIGS. 15 to 17 relate to a fourth embodiment of the present invention. FIG. 15 is a block diagram showing a configuration of a signal processing unit of an electronic endoscope apparatus, FIG. 16 is a configuration diagram of a light source unit, and FIG. 5 is a flowchart relating to white balance adjustment.

The electronic endoscope apparatus of the present embodiment is an apparatus capable of processing both single-color (simultaneous) imaging and plane-sequential imaging. The light source unit shown in FIG.
5 is connected to the signal processing unit shown in FIG. And
The electronic endoscope apparatus is configured to change the operation of the white balance of the signal processing unit by detecting that an abnormality has occurred in the light source unit and switching to the emergency light.

In the signal processing section shown in FIG. 15, a circuit that requires different operations between single-chip color imaging and field-sequential imaging is configured by an FPGA (field programmable gate array). CPU2
By changing the wiring information (FPGA program) downloaded from 11, the signal processing can be performed by both methods. The FPGA program is CSIO2O
9 is provided. Further, the processing procedure and the like of the FPGA circuit are controlled in accordance with the process control given via the parallel I / O controller (PIO) 235. In the figure, the circuit constituted by the FPGA is:
This is indicated by a double frame.

Hereinafter, the configuration and operation of the electronic endoscope apparatus will be described.

It is assumed that the CCD 210 as the image pickup means is provided in, for example, an endoscope. The CCD 210
Captures an image under illumination light suitable for the imaging method emitted by the light source unit, and outputs an imaging signal. The imaging signal of the CCD 210 is supplied to the pre-signal processing unit, where it is processed by a processing operation suitable for the imaging method, and, for example, R, G, and B video signals are output.

First, signal processing for single-chip color imaging will be described.

In FIG. 15, 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) disposed on the imaging surface. The CCD 210 is
It is driven by a CCD drive signal of the CCD driver 213. The SSG 212 generates a drive signal for single-chip color imaging.

The read signal from CCD 210 is CD
The signal is demodulated by an S (correlated double sampling) circuit 214 and converted into a digital signal by an A / D converter 216 via an 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 an A / D converter 220 in order to adjust the amount of light emitted from the light source unit, and is input to a dimming detection circuit 221.

The dimming detection circuit 221 calculates the average level and brightness distribution of the image, and outputs the result to the CPU 211. The CPU 211 performs a dimming operation and outputs the result to a light source unit via a serial I / O controller (SIO) 222. The video signal after AGC adjustment is separated into a luminance (Y) and a color difference (RY, BY) signal by a color separation circuit 217, and color processing unique to various endoscope 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 outputs color balance information 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 the color correction value to the white balance (WB) control circuit 225.
This correction value is multiplied by each color difference signal to obtain a correct color balance.

The video signal subjected to the color correction operation is supplied to the gamma complement circuit 2
26, the memory input control circuit 227
Are stored in the three field memories (FM) 228, respectively. Each video signal of luminance and color difference read from each memory 228 is
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 by 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 to the outside as an RGB video signal.

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

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

The CCD 210 having no color mosaic filter on the imaging surface is used. Further, an FPGA program for field sequential imaging is given to a circuit configured by the FPGA of the signal processing unit.

RGB read from the CCD 210
The frame sequential signal is the same CDS / AG as in single-chip color imaging.
After the C processing, the image is input to the color separation circuit 217.
Since there is no need to perform a color separation process at the time of frame sequential imaging, this circuit 217 functions simply as a bypass circuit. After that, a signal subjected to color processing and white balance adjustment is input to the memory input control circuit 227. Here, RG
Control is performed so that a video signal input as a sequential signal of B is distributed to three frame memories 228.

Since the matrix operation at the subsequent stage is unnecessary as in the case of the color separation, the R operation synchronized with the memory 228 is performed.
The GB is also bypassed by the matrix circuit 229 and input to the color tone circuit 230 at the subsequent stage. The subsequent video signal processing is the same as in the single-chip color imaging method.

In the light source unit shown in FIG. 16, the dimming signal transmitted from the signal processing unit is input to the CPU 237 via the SIO 236. The CPU 237 generates a parallel I / O controller (PIO) based on the dimming signal.
A dimming control circuit 239 is controlled via 238 to drive a dimming light amount adjusting aperture blade 240.

Further, an instruction from the panel switch 241 is read by a PKDI (programmable key / display interface) 242, and LED display control, lamp control, rotation filter control and the like are performed. As an example, the rotation filter 2 is instructed from a panel switch 241 to specify a single-chip color imaging mode or a frame sequential imaging mode.
Reference numeral 45 denotes switching between insertion / removal of the illumination light source and the light guide 244 with respect to the optical path. The switching of the mode is communicated to the CPU 211 of the signal processing unit via the SIOs 236 and 222. Reference numeral 248 denotes a panel LED. Further, the rotary filter 245 includes a motor 250 controlled by a rotary filter control circuit 249.
Is to be rotated.

By the way, in the light source section of the endoscope apparatus, in order to secure a field of view even when the main illumination lamp 243 (mainly a xenon lamp) is turned off due to an abnormality during observation, For example, an emergency light 246 using a halogen lamp is provided. When the main lamp 243 is turned off, the CPU 237 of the light source unit detects this, 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 the lamp.

FIG. 17 is a flowchart of an interrupt process in the CPU of the signal processing unit.

When the SIO 222 receives the data from the light source unit, an interrupt occurs, and the processing task shown in FIG. 17 is started. If the received data is a code corresponding to the switching of the light source (emergency light detection) in step S1, in step S2, the CPU 211 reads the WB correction value for the halogen lamp stored in advance. Then, the correction value is output to the WB balance control circuit 225.
In step S3, the WB balance control circuit 225
In the above, a correction value corresponding to each color difference signal (in single-chip color imaging mode) or each RGB signal (in frame sequential imaging mode) is multiplied to obtain a standard color reproduction during halogen lamp illumination.

According to this embodiment, when the main lamp is abnormally turned off by the light source unit, the illumination is switched to the emergency light illumination, and this is communicated to the signal processing unit 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 an emergency light is turned on. This allows
Even if the lamp is switched, an observation image with good color reproducibility can be obtained.

FIG. 18 is a flowchart relating to white balance adjustment according to the fifth embodiment of the present invention.

The hardware configuration of the electronic endoscope apparatus of the present embodiment is the same as that of the fourth embodiment, and the description is omitted.

The flowchart shown in FIG. 18 shows a part of the timer interrupt processing of the CPU of the signal processing unit.
In this task, an operation for performing a process required at regular intervals, for example, reading a switching instruction from a panel, controlling LED lighting, and the like is described. One of these processes
First, processing for detecting a sudden change in the color of an image pickup signal is performed. That is, in steps S4 and S5, 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 switches from the normal illumination by the xenon lamp to the emergency illumination by the halogen lamp, the image of the same subject suddenly changes in the direction of decreasing the color temperature. Therefore, a change in the lamp can be detected from the image signal.

When switching to the emergency light is detected, the CP
U211 performs the following color correction operation. That is, in steps S7 and S8, the current white balance set value is read, and a correction operation corresponding to the change in the color temperature of the lamp is performed on the read value. In step S9, the result of the calculation is written into the WB balance control circuit 225, and the white balance is reset.

According to the present embodiment, a change in the lamp of the light source is detected based on the color information extracted from the image signal, and the white balance is shifted. It is possible to automatically perform color correction when an emergency light is turned on. In this embodiment,
As a color correction operation, a correction operation is performed on the current set value using the color correction value, so that more accurate color correction can be performed as compared with the fourth embodiment.

FIGS. 19 to 22 relate to a sixth embodiment of the present invention. FIG. 19 is a block diagram of a white balance detection circuit at the time of single-chip color imaging, and FIG. 20 is a block diagram of a white balance detection circuit at the time of frame sequential imaging. FIG. 21 is a timing chart of the circuit shown in FIG. 19, and FIG. 22 is a timing chart of the circuit shown in FIG.

The hardware configuration of the electronic endoscope apparatus according to the present embodiment is the same as that of the fourth embodiment, and a description thereof will be omitted.

The switching between the detection circuit for single-chip color imaging shown in FIG. 19 and the detection circuit for frame sequential imaging shown in FIG. 20 is performed by reprogramming the FPGA as described above.

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

A color difference signal (RY / BY) is input to 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 respective 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. 21, the input color difference signals have already been synchronized by the color separation circuit 217, so that RY and BY are input simultaneously. Therefore, resetting of each averaging circuit 251 and loading of the register (load) are common to the two color differences. The timing of this processing is loaded after one screen is completed, and a reset (res) is performed after this loading.

On the other hand, in the frame sequential imaging mode, RGB sequential signals are input to the R-Y input terminal in the single-chip color imaging mode in time series to the white balance detection circuit 224, and signals are input to the other terminals. Not done. Therefore, only one averaging circuit 251 is provided, and its output is 3
It has a circuit configuration distributed to two registers 252. Then, the control signal generation circuit 253 generates a control signal so that these three registers 252 store an average value of each of the RGB screens. That is, as shown in FIG. 22, the averaging circuit 251
Is reset for each screen. In addition, load (load
-R, load-G, load-B) are executed after the end of the screen of the color corresponding to each register 252.

According to the embodiment having the above configuration, 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 imaging can be performed by different imaging methods.

FIGS. 23 to 27 relate to a seventh embodiment of the present invention. FIG. 23 is a block diagram of a light source unit, FIG. 24 is a flowchart of white balance setting in a special light mode, and FIG. Block diagram showing the configuration,
FIG. 26 is a perspective view showing the configuration of single-wavelength illumination, and FIG. 27 is a perspective view showing the configuration of three-wavelength illumination.

In the electronic endoscope apparatus according to the present embodiment, the light source unit can emit special light such as infrared light in addition to ordinary white illumination light. The electronic endoscope apparatus is configured to detect a special light observation mode for detecting that illumination other than white light is being performed, and to set a white balance to a predetermined value during illumination other than white light. ing.

Since the hardware configuration of the electronic endoscope apparatus of this embodiment is the same as that of the fourth embodiment, FIG.
Is omitted, and only different points will be described.

Incidentally, in the field of electronic endoscopes, observation with special light such as infrared light is sometimes performed for the purpose of blood flow observation or the like. As a method for illuminating the special light, there are a method using a single wavelength and a method using a plurality of wavelengths.

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

In the case of performing observation using a plurality of wavelengths (in this case, images of the respective wavelengths are often quantitatively compared using an image processing device), RGB for plane-sequential illumination is used.
Instead of the rotary filters for illumination, illumination is performed by inserting rotary filters having filters for the respective wavelengths. The insertion / removal of these special light filters can be designated by the panel switch 291 of the light source unit shown in FIG. 23. At the same time, the CPU 237 of the light source unit controls them and transmits control information to the signal processing unit. I do.

FIG. 25 shows the configuration of the illumination optical system in the light source section of the electronic endoscope apparatus. The luminous flux emitted from the lamp 260 is divided into a first lens 261, a three-wavelength illumination rotation filter 262, a single-wavelength illumination filter 263, and a second lens 261.
Through the lens 264, the light enters the light guide 265 connected to the illumination optical system of the endoscope insertion section.

The single-wavelength illumination filter 263 is the same as that shown in FIG.
As shown in FIG. 6, a plurality of optical filters 271 to 273 are attached to a disk-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 a single-wavelength illumination control circuit 276 based on an instruction from the CPU 237 shown in FIG.

On the other hand, as shown in FIG. 27, the turret 280 of the three-wavelength illumination filter 262 is
4 rotates in synchronization with the image signal. At the time of special light observation, sequential illumination light of any three wavelengths can be obtained by using a turret 280 for special light in which a plurality of optical filters 281 to 283 having different transmission wavelength ranges are arranged.

Also, at the time of normal observation, by replacing the turret with three types of optical filters of red, green and blue, sequential illumination light of any three wavelengths can be obtained.

The entire rotary filter system can be moved by a detachable motor 285.
The illumination light 62 may be retracted from the optical path to stop the illumination light sequentially for three wavelengths.

As shown in FIG. 27, a rotating motor 284 having the turret fixed to a rotating shaft is provided on a support column of the moving member 287. The base of the moving member 287 is moved by the rotation of the attaching / detaching 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 based on instructions from the CPU 237 shown in FIG.

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

When 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 into the optical path to sequentially illuminate three wavelengths.

FIG. 24 is a flowchart of the SIO reception interrupt processing of the CPU of the signal processing unit in this embodiment.

When data from the light source unit is received, SIO
An interrupt is generated from 222, and the processing in FIG. 24 is performed. If the received data corresponds to the transition to the special light observation mode, the following processing is performed. In step S31, if the special light observation mode is the single wavelength observation, white balance adjustment processing is performed in steps S32 to S34 to set the RGB image output levels to the same. That is, during single wavelength observation, the image is monochrome.

In steps S31 and S35, if the special light observation mode is the multi-wavelength observation mode, step S31 is executed.
At 36, the white balance is reset, and each image is output to the outside at the same amplification.

According to the embodiment having the above-mentioned configuration, the white balance circuit is reset so that the output image is displayed in monochrome when special light of a single wavelength is observed, so that an easy-to-view image can be displayed. Further, in the present embodiment, at the time of special light observation of a plurality of wavelengths, by outputting the obtained three wavelength images at the same level ratio, diagnosis and evaluation by an image processing device or the like can be easily performed. is there.

In this embodiment, white balance control is performed so that a monochrome image is obtained when a single wavelength is observed. However, it will be understood that a color tone other than monochrome can be easily set.

FIGS. 28 to 33 relate to the eighth embodiment of the present invention. FIG. 28 is a schematic diagram of an electronic endoscope, FIG. 29 is an explanatory diagram of a monitor screen, and FIG. FIG. 31 is an explanatory diagram of AGC detection,
FIG. 32 is a circuit diagram showing one configuration of the GCA control unit, and FIG. 33 is a circuit diagram showing another configuration of the GCA control unit.

[0165] The electronic endoscope apparatus of this embodiment is similar to 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 sets a threshold value in AGC detection of the signal processing unit 303 or sets a detection range during flash irradiation. Is changed.

Light emitted from the xenon lamp 304 of the light source unit 302 passes through the light guide 305 to the endoscope 30.
The object is irradiated from the front side. The reflected light from the subject is incident on a CCD 306 that is also arranged on the front of the endoscope 301. The CCD 306 is driven by a driving signal generated by a CCD driving circuit 307 inside the signal processing unit 303, and photoelectrically converts incident light into an electric signal.
This electric signal is supplied to a signal line 308 passing through the endoscope 301.
Through the CDS circuit 309 in the signal processing unit 303 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 level, and is input to the A / D converter 314.

The AGC circuit 310 includes 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 passes through an A / D converter 313 and is sent to a parent screen memory 314.
And stored in the child screen memory 315. The writing / reading of the parent screen memory 314 and the child screen memory 315 is controlled by the SSG 316.

Normally, a moving image whose contents are sequentially updated is output only from the main screen memory 314 and displayed on the monitor.

At the time of freeze, updating of the contents of the parent screen memory 314 is prohibited, and a still image is output. On the other hand, a moving image whose contents are sequentially updated is output from the child screen memory 315. After the still image and the moving image are combined, D /
A conversion is performed and displayed on the monitor.

The CCD drive circuit 307 drives the CCD 306 in the shutter mode under the control of the processor CPU 300 that has received the freeze command. Further, the SSG 316 reads the main screen memory 314 in a freeze mode under the control of the processor CPU 300 that has received the freeze command.

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

On the other hand, the electric signal output from the CCD 306 is also transmitted to the light control circuit 31 inside the signal processing unit 303.
9 to generate a dimming signal. The light control circuit 319 controls the stop 32 in the light source unit 302 according to the light control signal.
The aperture amount of 0 is adjusted, and control is performed so that the amount of light illuminating the subject becomes appropriate. Further, the dimming circuit 319
Is configured to output a detection pulse to the processor-side CPU 300 when an appropriate exposure amount is detected.

The light source side CPU 321 of the light source section 302 controls the irradiation mode of the xenon lamp 304 via a 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 strong light is emitted intermittently. The light source side CPU 32
1 outputs an AGC detection control signal to the GCA control unit 312 of the signal processing unit 303 when instructing the flash mode.

Here, the freeze operation in the CCD 306 shutter (element shutter) mode will be described. 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 provided to the CPU 321 of the light source unit 302,
The U 321 instructs the xenon lamp power supply 322 to switch the irradiation mode to perform the flash irradiation. When the xenon lamp 304 irradiates the flash, the amount of light is increased to compensate for the insufficient amount of light during the shutter operation of the CCD.
Under the control of the PU 300, the image of the main screen is frozen. 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, but the moving image is displayed on the child screen.

In the flash irradiation, since the irradiation light continues for a certain period of time after the freeze, the CCD 306, which has returned to the normal drive after the freeze, temporarily becomes overexposed to the irradiation light. In this state, the AGC circuit 310 reacts, and an unsightly image such as hunting is displayed on the child 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. 29 shows a display screen of the monitor. For the sake of explanation, it is assumed that the upper right portion of the main screen is sufficiently illuminated, and the other hatched portions are insufficiently illuminated.

Assuming that 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 in FIG. 29A becomes as shown in FIG. The video signal in the upper right part of the screen is temporarily saturated by 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 lower than the threshold value.

The switching of the AGC control method may be performed as follows.

The GCA control unit 312 divides the effective screen into a plurality of areas as shown in FIG. 31 and, for example, from the divided areas, a peripheral area of the screen where the video signal is less saturated (in the figure, The process is changed to a process of controlling the gain using only the video signal in the hatched area).

For example, when observing the stomach wall and the like,
The center of the screen is saturated with respect to the periphery of the screen. Therefore, it is effective to change the AGC operation using only the video signal in the peripheral region of the screen where the saturation tendency is low.

FIG. 32 shows a specific example of the circuit configuration of the GCA control section 312. The CDS output passes through an inverting amplifier IC1 and is input to a limiter circuit IC2. Limiter circuit I
In 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 having the upper limit is output. As for this limiter signal, only a desired signal in one screen is converted into a GCA control voltage by the LPF / hold circuit 323 by the switch SW2 controlled to open and close by the mask signal. The LPF / hold circuit 323 includes a resistor, a capacitor, and a buffer.

FIG. 33 shows another configuration example of the GCA control section 312. In the GCA control unit 312, a mask signal is generated by the mask signal generation circuit 324 according to the AGC detection control signal without changing the input CDS output, and the range of detection is changed.
The timing of generation of the mask signal is determined by the vertical synchronization signal V
The timing is synchronized with D and the horizontal synchronization signal HD.

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

FIGS. 34 and 35 relate to a ninth embodiment of the present invention. FIG. 34 is a schematic diagram of an electronic endoscope, and FIG.
4 is a timing chart showing the operation of the device 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 shut off to maintain a constant gain. It has a configuration. In addition, the same configurations and operations as in the eighth embodiment are denoted by the same reference numerals, and description thereof is omitted.

The apparatus of the present embodiment differs from the signal processing section 303 of the eighth embodiment in that the GCA control section 312 is used instead of the GCA control section 312.
AGCon / off output from the light source side CPU 325
GCA that controls AGC operation / shutdown by control signal
It has a control unit 326.

A freeze operation in the CCD shutter (element shutter) mode in the above configuration will be described with reference to FIG.

First, it is assumed that the CCD shutter mode command shown in FIG. 35A has been selected. In this state,
When the freeze command shown in FIG. 35B is input by the operation of the observer, the CCD driving circuit 307 causes the CCD 306 to perform a 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. When the xenon lamp 304 irradiates the flash, the light amount is increased to compensate for the light amount shortage during the shutter operation of the CCD. The dimming circuit 319 detects the appropriate exposure amount, and when the proper exposure amount is reached, the processor C
An appropriate exposure amount detection pulse shown in FIG. 35D is output to the PU 300. The processor-side CPU 300 receives the detection pulse, and freezes the image of the main screen.
The reading of the main screen memory 314 is controlled via the SSG 316. In this manner, the image at the time when the proper exposure amount is obtained is displayed as a still image on the parent screen on the monitor.

On the other hand, since the child screen displays a moving image, in order to prevent the display of an unsightly image such as the hunting described above, the operation of the present embodiment is changed as described below.

The AGCoff control signal shown in FIG. 35E together with the flash irradiation command is sent to the GCA control unit 326.
Given to. Then, based on the information for switching 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 end of the flash irradiation.

According to the present embodiment, in order to obtain an appropriate exposure amount during the freeze operation in the CCD shutter mode,
Even when the flash irradiation is performed, the AGC control is interrupted and the gain is held. As a result, in this embodiment,
An unsightly image such as hunting generated by a reaction of the AGC to the flash irradiation can be prevented from being displayed on the monitor, and an appropriate observation image can be obtained.

FIG. 36 is a schematic structural view of an electronic endoscope apparatus according to the tenth embodiment of the present invention.

The electronic endoscope apparatus of the present embodiment has a light source 32
The xenon lamp 304 and the emergency light 3 are normal lights 8
31 are provided. The light source section 328 is configured to switch to the emergency light 331 and illuminate when the xenon lamp 304 is cut off. In addition, the same configurations and operations as those of the eighth embodiment are denoted 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 a filter 332 for reducing the amount of light, and then passes through the light guide 30.
5 is incident. Illumination light passing through the light guide 305 in the endoscope 301 is applied to the subject from the front of the endoscope, and the reflected light is incident on the CCD 306 also arranged on the front of the endoscope. This CCD 306 is a signal processing unit 329
Driven by the drive signal generated by the internal CCD drive circuit 307, the incident light is photoelectrically converted and converted into an electric signal. This electrical signal is automatically 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 unit 340 for changing a gain in accordance with a signal provided from the light source unit 339 and for determining switching of a lamp.

On the other hand, the CPU 335 in the light source unit 328
The current value flowing to the xenon lamp power supply 336 that supplies power to the xenon lamp 304 is monitored. Here, a sharp decrease in the current value causes the xenon lamp 304
When the CPU 335 determines that the disconnection has occurred, the CPU 335 controls the motor 338 through the drive circuit 337, moves the emergency light 331 on the optical axis, and turns on the emergency light 331.

Here, in an electronic endoscope apparatus, generally, an emergency light having a lower light quantity than a xenon lamp for diagnosis is used. It becomes darker than when using a xenon lamp.

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

If it is determined that the emergency lamp is turned on, the maximum gain of the AGC is increased by the GCA gain control unit 340 of the GCA circuit 333 from the value set when the xenon lamp for checking is turned on. Control to be performed.

According to the present embodiment, the maximum gain of the AGC is set low in response to a decrease in the amount of illumination light even when switching to emergency light lighting due to disconnection of the xenon lamp for inspection that occurred during observation with the endoscope. As a result, 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 case.
The same effect can be obtained even if the variable range of the gain is changed in order to secure a sufficient field of view even if / N is sacrificed.

FIGS. 37 and 38 relate to the eleventh embodiment of the present invention. FIG. 37 is a schematic configuration diagram of an electronic endoscope apparatus, and FIG. 38 is a block diagram showing a configuration example of a GCA control unit.

The electronic endoscope apparatus of the present embodiment has a light source
1 is configured to be capable of switching and illuminating illumination light for plane-sequential imaging and illumination light for homogeneous imaging. The signal processing unit 342 is configured to drive the CCD 306 by switching between the field sequential imaging method and the homogeneous imaging method, and to switch the signal processing according to the method. Then, the electronic endoscope apparatus is configured to determine whether the irradiation mode of the light source is for plane-sequential imaging or for homogeneous imaging, and to change the AGC detection method according to the determined imaging method. ing. Other configurations and operations similar to those of the eighth embodiment are denoted by the same reference numerals, description thereof will be omitted, and only different points will be described.

The switching means provided on a front panel or the like (not shown) determines whether the illumination light is to be used for the frame sequential imaging or for the simultaneous imaging, and is input to the light source CPU 343 of the light source unit 341. You. Light source side C
When the illumination light for the field 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 rotates the filter 344 by the motor 345. 3
46 is controlled.

When the illumination light for simultaneous imaging 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 illuminating light is incident on the light guide 305 and illuminates the subject from the front of the endoscope.
The reflected light is subjected to photoelectric conversion by the CCD 306 disposed at the end of the endoscope, and is converted into an electric signal.

Inside the signal processing section 342, there are provided a plane sequential CCD drive circuit 347 for driving the CCD 306 for plane sequential imaging, and a simultaneous CCD drive circuit 348 for driving the CCD 306 for simultaneous imaging. I have.

The signal processing unit 342 has a GCA
At the subsequent stage of the circuit 349, a signal processing unit 350 for a frame sequential type and a signal processing unit 351 for a simultaneous type are provided. These two
The CCD drive circuits 347 and 348 and the signal processing circuits 350 and 351 of the system are selected by switches 353 and 354 according to the illumination light currently being irradiated by an illumination light discriminating circuit 352 provided inside the light source 341. It is supposed to be.

The electric signal read from the CCD 306 is transmitted to the CDS 30 via a cable 308 in the endoscope.
After that, the data is input to the GCA 349. The CDS output is
In the GCA 349, automatic gain control is performed so that the level becomes the set level, 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 includes the gain control amplifier 311 and a GCA controller 355 for controlling the gain of the amplifier 311.

Next, the operation of GCA control section 355 controlling the AGC operation will be described.

[0213] When the field sequential imaging is selected as the illumination light of the light source 341, the output of the CCD 306 is, for example, RGB.
.. Are transmitted in the field cycle in the order of BR. From these, the control voltage of the GCA 311 is determined based on a value obtained by integrating only the G video signal component in the CDS output.

Note that a B signal component and an R signal component can 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, such as a combination of a G component and an R component. Alternatively, the R, G, and B signals sequentially output are integrated, multiplied by a multiplier, and added to obtain an integrated value of the luminance component Y. Using this value, the control voltage of the GCA is determined. Is also good.

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

FIG. 38 is a block diagram showing a configuration example of the GCA control section 355.

When the illumination light is of the field sequential type, the CD
The signals sent in the order of R, G, B,... To the S output are switched by the switch signal generation circuit 356 by the switch 357, and distributed to three LPF / hold circuits 358, respectively. The signals held by the three LPF / hold circuits 358 are multiplied by coefficients by the three multipliers 359, and then added by the adder 360 to obtain an integrated luminance signal Y. GCA control voltage.

The switching signal generation circuit 356 controls opening and closing of the switch 357 in accordance with the illumination light discrimination output of the illumination light discrimination circuit 352.

When only the G component is used,
This can be achieved by changing the switching of the switch 357.

When the illumination light is of the simultaneous imaging type, the control voltage of the GCA can be taken out by fixing the switch 357 only at one position at all times.

In this embodiment, the detection method of AGC on the processor side is automatically optimized by the illumination light mode of the light source, so that an electronic endoscope with good operability which is free from complicated setting can be obtained. Can be provided.

FIGS. 39 to 42 relate to a twelfth embodiment of the present invention. FIG. 39 is a schematic structural view of an electronic endoscope apparatus, and FIGS.
0 is a configuration diagram showing the filter arrangement of the rotary filter, FIG.
Is a configuration diagram relating to speed detection of the rotary filter, and FIG.
FIG. 4 is an explanatory diagram related to reading of a CD and control of a memory.

The electronic endoscope apparatus of the present embodiment shown in FIG. 39 irradiates a subject with plane-sequential illumination light via the light guide 369 and an electronic endoscope 371 having a light guide 369 and a CCD 370. Light source unit 372 and CC
And a signal processing unit 373 that drives the D370 and processes the obtained imaging signal to output a video signal.

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

The CCD 370 is connected to the C of the signal processing unit 373.
It is driven by a CD drive circuit 378 and converts a subject image into an image pickup signal. The output of the CCD 370 is output to the signal processing unit 37.
3 are A / D converted by the A / D converter 379, synchronized by the memory 380, and D / A converted by the D / A converter 381.
It is converted and output as a video signal.

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

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

FIGS. 40A to 40C show examples of the structure of the rotary filter 375. FIG. For example, FIG.
In the case of a filter in which R, G, and B shown in (a) are arranged in order, a CCD shown in FIG.
The CCD 370 is driven by the CCD drive circuit 378 so as to read out the image signal from the 370. The imaging signal read from the CCD 370 is A / D converted and stored in the memory 3.
80, time-series R, G, B data is synchronized, and the R, G, B data is D / A converted to obtain and output a video output.

Similarly, R, R, G, and R shown in FIG.
FIG. 42B shows the case of a filter arranged as G, B, B.
The CCD 370 is driven and read at the timing shown in FIG.
Synchronization is performed by the memory 380. In the case of a filter in which a shielding portion is arranged between R, G, and B shown in FIG. 40 (c), the CCD 370 has the timing shown in FIG.
And read it out, and the memory 380 synchronizes it.
In the case of the rotary filter shown in FIG.
The timing shown in FIG.

Here, it is assumed that an image is normally taken at a rotation cycle of 20 Hz. When the screen becomes dark and normal imaging cannot be performed, the rotation cycle is set to 10 Hz or 5 Hz, and the image is taken at a slow speed. An image is taken with the rotation cycle increased to a speed that suits.

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 or inner circumference of the rotation filter as shown in FIGS. 41 (a) and 41 (b). The mark 383 is read by the rotation filter rotation speed discrimination circuit 377, and the CC
The D drive circuit 378 and the memory control circuit 382 are controlled.

The rotation filter rotation speed determination circuit 377
Can be detected based on the difference in the amount of reflected light between the mark 383 and a portion where the mark 383 is not provided.

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.

FIGS. 43 to 46 relate to a thirteenth embodiment of the present invention. FIG. 43 is a schematic structural view of an electronic endoscope apparatus.
4 is a configuration diagram showing a filter opening of the rotary filter, FIG.
FIG. 46 is a configuration diagram relating to the detection of the aperture ratio of the rotary filter, and FIG. 46 is an explanatory diagram relating to CCD reading and memory control.

The electronic endoscope apparatus according to the present embodiment determines the aperture ratio of the rotary filter of the light source, and determines C
The drive of the CD and the control of the memory are changed. In addition, the same components and operations as those of the twelfth embodiment are denoted by the same reference numerals, description thereof will be omitted, and only different points will be described.

The light source section 372 of this embodiment has a rotary filter aperture determining circuit 385 instead of the rotary filter speed determining circuit 377 of the twelfth embodiment.

The light separated into each color through the rotation filter 375 is irradiated on the subject through the light guide 369, and the reflected light is imaged by the CCD 370.

For example, in the case of a filter in which a shielding portion is arranged between R, G, and B shown in FIG.
At the timing shown in FIG. 3C, the CCD driving circuit 378 controls the CCD 370 to read out the imaging signal from the CCD 370.
370 is driven. The imaging 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 subjected to D / A conversion to obtain an image. Get the output and output.

Similarly, R, R, G, and R shown in FIG.
In the case of filters arranged as G, B, and B, FIG.
The CCD 370 is driven and read at the timing shown in FIG. Note that FIG.
In the case of the rotary filter of (a), the timing shown in FIG.

As an example of a configuration for determining the aperture ratio of the rotary filter, as shown in FIGS. 45 (a) and 45 (b), a bar code is applied to the outer or inner circumference of the rotary filter 375.
The bar code is read and determined by the rotation filter aperture determination circuit 385. Thus, 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 determined, and the driving of the CCD and the control of the memory are automatically controlled. Video can be obtained.

Although an example is shown in which the determination is made by marking a bar code, the determination may be made by driving as shown in FIG. 46B and detecting whether or not there is a light-shielding portion from the CCD output.

In each of the above embodiments, the imaging 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.

[0244]

The electronic endoscope apparatus according to the present invention has an effect that the optimal signal processing operation of the image pickup signal can be changed in accordance with the illumination mode of the illumination light generating means.

[Brief description of the drawings]

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

FIG. 2 is a block diagram related to a light source and signal processing of the apparatus.

FIGS. 3 to 5 relate to a first embodiment, and FIG. 3 is an overall configuration diagram of an electronic endoscope apparatus.

FIG. 4 is a block diagram of a white balance circuit.

FIG. 5 is a block diagram of a white balance circuit different from FIG. 4;

6 to 10 relate to a second embodiment, and FIG. 6 is an overall configuration diagram of an electronic endoscope device.

FIG. 7 is a block diagram showing a configuration example of a video signal processing circuit.

FIG. 8 is an explanatory diagram of chromaticity conversion.

FIG. 9 is a characteristic diagram of a normal light and an emergency light.

FIG. 10 is a flowchart relating to change / setting of a matrix coefficient.

11 to 14 relate to a third embodiment, and FIG. 11 is a block diagram showing a schematic configuration of an electronic endoscope apparatus.

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

FIG. 13 is a block diagram of a simultaneous signal processing circuit.

FIG. 14 is a block diagram of a frame sequential signal processing circuit.

FIGS. 15 to 17 relate to a fourth embodiment, and FIG. 15 is a block diagram showing a configuration of a signal processing unit of the electronic endoscope apparatus.

FIG. 16 is a configuration diagram of a light source unit.

FIG. 17 is a flowchart relating to white balance adjustment.

FIG. 18 is a flowchart relating to white balance adjustment according to a fifth embodiment.

19 to 22 relate to a sixth embodiment, and FIG. 19 is a block diagram of a white balance detection circuit at the time of single-plate color imaging.

FIG. 20 is a block diagram of a white balance detection circuit at the time of frame sequential imaging.

FIG. 21 is a timing chart of the circuit shown in FIG. 19;

FIG. 22 is a timing chart of the circuit shown in FIG. 20;

23 to 27 relate to a seventh embodiment, and FIG. 23 is a block diagram of a light source unit.

FIG. 24 is a flowchart of white balance setting in a special light mode.

FIG. 25 is a block diagram showing a configuration of an optical system of a light source unit.

FIG. 26 is a perspective view showing the configuration of single-wavelength illumination.

FIG. 27 is a perspective view showing a configuration of three-wavelength illumination.

28 to 33 relate to an eighth embodiment, and FIG. 28 is a schematic configuration diagram of an electronic endoscope.

FIG. 29 is an explanatory diagram of a monitor screen.

30 is a waveform diagram of a video signal of a scanning line A on the screen shown in FIG. 29.

FIG. 31 is an explanatory diagram of AGC detection.

FIG. 32 is a circuit diagram showing one configuration of a GCA control unit.

FIG. 33 is a circuit diagram showing another configuration of the GCA control unit.

FIGS. 34 and 35 relate to the ninth embodiment, and FIGS.
4 is a schematic configuration diagram of an electronic endoscope.

FIG. 35 is a timing chart showing the operation of the device shown in FIG. 34;

FIG. 36 is a schematic configuration diagram of an electronic endoscope apparatus according to a tenth embodiment.

37 and 38 relate to an eleventh embodiment, and FIG. 37 is a schematic configuration diagram of an electronic endoscope apparatus.

FIG. 38 is a block diagram showing a configuration example of a GCA control unit.

FIGS. 39 to 42 relate to a twelfth embodiment,
FIG. 39 is a schematic configuration diagram of an electronic endoscope apparatus.

FIG. 40 is a configuration diagram showing a filter arrangement of a rotary filter.

FIG. 41 is a configuration diagram relating to speed detection of a rotary filter.

FIG. 42 is an explanatory diagram relating to CCD reading and memory control.

FIGS. 43 to 46 relate to a thirteenth embodiment,
FIG. 43 is a schematic configuration diagram of an electronic endoscope apparatus.

FIG. 44 is a configuration diagram showing a filter opening of a rotary filter.

FIG. 45 is a configuration diagram relating to detection of an aperture ratio of a rotary filter.

FIG. 46 is an explanatory diagram relating to CCD reading and memory control.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Electronic endoscope apparatus 2 ... Electronic endoscope 3 ... Light source device 4 ... Processor 9 ... Video signal processing circuit 13 ... Solid-state image sensor 18 ... Distinction signal generator 19 ... Distinction circuit 26 ... Preprocessing circuit 27 ... White balance Circuit 30 ... Post-processing circuit

──────────────────────────────────────────────────続 き Continuing on the front page (51) Int.Cl. ⁶ Identification symbol FI H04N 7/18 H04N 7/18 M (72) Inventor Yasuo Komatsu 2-43-2 Hatagaya, Shibuya-ku, Tokyo Olympus Optical Industrial Co., Ltd. Judge Kunio Matsumoto Judge Kenji Hashiba Judge Judge Keiji Fujiwara (56) References JP-A-64-86934 (JP, A) JP-A-63-240826 (JP, A) JP-A-1-306810 ( JP, A) JP-A-2-181159 (JP, A) JP-A-1-191593 (JP, A) JP-A-62-296689 (JP, A)

Claims (7)

(57) [Claims] An illumination light generating means for generating illumination light by switching between a first illumination mode and a second illumination mode; and Table image signals including color information of the object image
Signal processing means for processing into a signal displayable on the display means; and a part of the signal processing means,
Control the white balance of the image signal based on the
A white balance circuit that outputs a control signal, and the white balance that the white balance circuit outputs.
An illumination mode detection unit that detects the illumination mode of the illumination light generation unit based on a control signal of the illumination, and the signal processing unit according to a detection result of the illumination mode detection unit. An electronic endoscope apparatus, comprising: signal processing operation changing means for changing to a signal processing function corresponding to a second illumination mode. 2. An illumination device according to claim 1, wherein the illumination is performed by ordinary light generated by an ordinary light lamp.
The first illumination mode for lighting and the special light observation filter
Special light different from the normal light inserted in the optical path of the illumination light
To switch to the second illumination mode for lighting
Illuminating light generating means for illuminating a body , and imaging based on the illuminating light illuminated by the illuminating light generating means.
Means for processing an imaging signal including color information of the subject image captured by the means.
Signal processing means, and an illumination mode for determining the illumination mode of the illumination light generating means.
The signal according to a determination result of the lighting mode determination means and the illumination mode determination means.
Processing means for the first illumination mode or the second illumination mode;
Signal processing function to change to the signal processing function corresponding to
An electronic endoscope apparatus comprising: a work changing unit . 3. A first lighting mode for lighting with a normal light lamp.
And the second lighting mode using the emergency lamp
Illumination light generating means for illuminating a subject , and imaging based on the illumination light illuminated by the illumination light generating means.
Processing an image signal including the color information of the photographic object image captured by the means
Signal processing means, and an illumination mode for determining the illumination mode of the illumination light generating means.
The signal according to a determination result of the lighting mode determination means and the illumination mode determination means.
Processing means for the first illumination mode or the second illumination mode;
Signal processing function to change to the signal processing function corresponding to
An electronic endoscope apparatus comprising: a work changing unit . 4. A first illumination for illuminating a subject with continuous light.
Mode and the second illumination mode with flash light.
An illumination light generating means for generating illumination light instead, and an image pickup based on the illumination light illuminated by the illumination light generating means.
Means for displaying an image signal including color information of a subject image taken by the means.
Signal processing means for processing into a signal that can be displayed on the indicating means, and a predetermined extraction of the image signal output from the image capturing means
Extracted under the conditions, and the signal level of the
Automatic gain control means for amplifying the imaging signal based on
An illumination mode for determining the illumination mode of the illumination light generating means.
The automatic mode according to the determination result of the lighting mode
The condition for extracting the imaging signal by the gain control means is
A first extraction strip set in advance corresponding to one illumination mode
Or a preset value corresponding to the second lighting mode.
Signal processing operation changing means for changing to the selected second extraction condition
When the electronic endoscope apparatus comprising the. 5. An object is illuminated with illumination light for a frame sequential method.
The subject is illuminated by the first illumination mode and the simultaneous illumination light.
Switch to the second illumination mode to generate illumination light
Illumination light generating means, and imaging based on the illumination light illuminated by the illumination light generating means.
Means for displaying an image signal including color information of a subject image taken by the means.
Signal processing means for processing into a signal displayable on the display means; and a white balance circuit provided in the signal processing means.
Detecting the white balance of the image signal
A white balance detection circuit for detecting the illumination mode of the illumination light generating means.
And over de detection means, in accordance with a detection result of the illumination mode detecting means, said Hua
The light balance detection circuit in the first illumination mode or
A signal for changing to a detection function corresponding to the second illumination mode
An electronic endoscope apparatus comprising: a signal processing operation changing unit . 6. A rotary filter for field sequential illumination for a first rotation.
A first illumination mode in which illumination light is emitted while rotating at a speed
And rotating the field-sequential illumination rotary filter at the second rotation speed.
Switch to the second illumination mode to irradiate illumination light
Illumination light generating means for illuminating a subject , and imaging based on the illumination light illuminated by the illumination light generating means.
Means for receiving an image signal including color information of a subject image taken by the means.
Signal processing means for performing signal processing, and an illumination mode for detecting the illumination mode of the illumination light generating means.
And over de detection means, in accordance with a detection result of the illumination mode detecting means, said signal
Processing means for the first illumination mode or the second illumination mode;
Signal processing function to convert to the signal processing function corresponding to the bright mode
An electronic endoscope apparatus comprising: a work changing unit . 7. A first field sequential illumination having a first aperture ratio.
A first illumination mode for illuminating a subject using a rotation filter.
And a second field-sequential illumination rotary frame having a second aperture ratio.
A second illumination mode for illuminating a subject image using a filter;
Switching means for illuminating a subject image, and driving means for driving an imaging means for capturing the subject image
And, based on the illumination light illuminated by the illumination light generating means,
An image pickup signal including color information of a subject image picked up by an image pickup unit
Signal processing means for performing signal processing on the illumination light , and an illumination mode for determining the illumination mode of the illumination light generation means.
The drive mode according to a determination result of the illumination mode determination means.
Means and said signal processing means respectively in said first illumination
Mode or a driving condition corresponding to the second illumination mode.
An electronic endoscope apparatus comprising: signal processing changing means for converting a signal processing function into a signal processing function .