JP2000139833A - Electronic endoscope device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the number of isolation elements between a patient circuit and a secondary circuit and to lower the using frequency of the isolation elements. SOLUTION: The video signals of two channels from CCD 5 are given to memories 26 and 27 from CDS 22 and 23 through A/D converters 24 and 25. The memories 26 and 27 alternately output the video signal of each stored channel. Thus, the video signals of the two channels stored in the memories 26 and 27 are time-division-multiplexed and supplied for the secondary circuit through the photocoupler 28 of one system. Thus, the number of the isolation elements is reduced.

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 suitable for an apparatus having a solid-state image sensor having a plurality of transfer paths.

[0002]

2. Description of the Related Art In recent years, endoscopes have been widely used for diagnosis in the medical field and for treatment using a treatment tool.
An image pickup device such as a charge-coupled device (CCD) is provided at the distal end of the endoscope, and the interior of the body cavity is sequentially illuminated with three color lights of red, green, and blue, and a color image of the inside of the body cavity is obtained by a plane sequential electronic endoscope. Various devices are also used.

[0003] In the case of a medical endoscope, a circuit section (patient circuit) inserted into a patient's body and a circuit section (secondary circuit) connected to peripheral devices such as a television monitor are safe. Must be electrically insulated to ensure. For this reason, signal transmission between the patient circuit and the secondary circuit is performed via an isolation element such as a photocoupler or a pulse transformer. As described above, an electronic endoscope apparatus having means for performing A / D conversion of a signal from an imaging means by a patient circuit, isolating the digital signal and transmitting the digital signal to a secondary circuit is disclosed in Japanese Patent Application Laid-Open No. 63-318927. No. pp. 147-64.

Recently, there is a high demand for higher resolution CCDs.
For this reason, the drive frequency has been increased. In addition, the number of bits has been increased due to a demand for higher image quality, and the speed and the number of isolation elements have been increased.

[0005]

As described above, in the above-mentioned conventional electronic endoscope apparatus, the speed and the number of the isolation elements between the patient circuit and the secondary circuit are increased due to the demand for higher image quality. There was a problem that an increase was necessary.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and reduces the number of isolation elements between a patient circuit and a secondary circuit and reduces the operating frequency of the isolation elements, thereby reducing costs. It is another object of the present invention to provide an electronic endoscope apparatus capable of reducing current consumption.

[0007]

According to the electronic endoscope apparatus of the present invention, an electric charge based on an optical image is accumulated in a solid-state imaging device during an exposure period, and the electric charge accumulated during a light-shielding period is read out by a plurality of channels. Driving means for outputting as a signal, and a plurality of storage means provided in the patient circuit and respectively holding a plurality of channels of video signals from the solid-state imaging device,
By performing readout from the plurality of storage units during the exposure period and the light-shielding period, the video signals of the plurality of channels are time-division multiplexed or frequency-converted to be electrically isolated from the patient circuit. Reading means for outputting to a circuit.

In the present invention, the driving means reads out the electric charges accumulated during the exposure period in a plurality of channels during the light-shielding period, and outputs as a video signal. These video signals of a plurality of channels are respectively stored in a plurality of storage units. The reading means performs reading from the plurality of storage means during the exposure period and the light shielding period, and time-division multiplexes or frequency-converts the video signals of the plurality of channels. By time-division multiplexing, video signals of a plurality of channels are combined into a video signal of one channel. Further, by performing frequency conversion, the rates of video signals of a plurality of channels can be reduced. The read video signal is output to the secondary circuit.

[0009]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIGS. 1 to 3 relate to a first embodiment of the present invention, and FIG. 1 is a block diagram showing an embodiment of an electronic endoscope apparatus according to the present invention. FIG. 2 is an explanatory view showing reading from the CCD, and FIG. 3 is a flowchart for explaining the operation of the first embodiment.

The present embodiment is provided in a patient circuit in a plane sequential electronic endoscope apparatus which sequentially illuminates with three color lights of red, green and blue and transfers electric charges through two channels during a light-shielding period. The memory is configured to reduce the number of photocouplers by time-division multiplexing two-channel signals into one channel and transmitting the resulting signals to a secondary circuit.

As shown in FIG. 1, the electronic endoscope apparatus includes an electronic endoscope 1, a video processor 2, a light source device 3, and a television monitor 4. The electronic endoscope 1
It has an elongated insertion section 7 having flexibility, and a CCD 5 as a solid-state imaging device is built in at the tip side of the insertion section 7. The insertion section 7 is also provided with a light guide 6 for guiding illumination light from the light source device 3.

The light source device 3 includes a condenser lens 11, a rotary filter 12, and a lamp 13. Lamp 13
From the condenser lens 1 pass through a rotary filter 12 having red, green, and blue color transmission filters attached thereto.
The light is condensed by 1 and guided to the light guide 6. The light guide 6 transmits the incident light to the distal end of the electronic endoscope 1 and sequentially irradiates light of each wavelength of red, green, and blue toward a subject (not shown).

The CCD driver 21 of the video processor 2
Outputs a drive signal for driving the CCD 5. This drive signal is supplied to the CCD 5 via a signal line provided in the insertion section 7. Thus, the CCD 5 photoelectrically changes the optical image from the subject, and supplies the video signal to the CDSs (correlation double sampling circuits) 22 and 23 of the video processor 2 via the signal lines in the insertion unit 7. I have.

That is, the CCD 5 receives light from a subject incident on each pixel, and accumulates charge corresponding to the amount of incident light in each pixel.
The stored charge is output as a video signal in response to a drive signal from the CCD driver 21. CC
D5 is capable of two-channel reading. Figure 2 shows CC
The data transfer from D5 is shown.

As shown in FIG. 2, the CCD 5 has a light receiving section 35 and output registers 36 and 37 for two channels. The charges accumulated in the light receiving section 35 in accordance with the amount of incident light are transferred to output registers 36 and 37 corresponding to two lines and output. The outputs of the A channel and the B channel from the CCD 5 are output from the video processor 2 respectively.
Are supplied to the CDSs 22 and 23.

In the present embodiment, the CCD 5
Under the control of the CD driver 21, charges are transferred during the light-shielding period.

The CDSs 22 and 23 double-sample and hold the read signals of the A and B channels from the CCD 5 and output them to A / D converters 24 and 25, respectively. By the CDSs 22 and 23, 1 / f noise and reset noise included in the output signal of the CCD 5 are removed, and a signal with an improved S / N ratio is obtained.

A / D converters 24 and 25 convert input signals into digital signals. In the present embodiment, the outputs of the A / D converters 24 and 25 are stored in memories 26 and 27.
It is supplied to. The memories 26 and 27
A is controlled by a memory controller (not shown).
The outputs of the / D converters 24 and 25 are held and output to the photocoupler 28 in a time sharing manner. That is, while the patient circuit is constituted by two circuits of A and B channels, reading from the memories 26 and 27 is performed in a time-division manner, so that the circuits after the photocoupler 28 are constituted by one system. Making it possible.

The photocoupler 28 supplies A and B channel signals from the memories 26 and 27 to a signal processing circuit 29. The signal processing circuit 29 performs predetermined signal processing such as white balance processing, gamma conversion processing, contour enhancement processing, and RGB synchronization processing on the input video signal,
Output to the D / A converter 30.

The D / A converter 30 converts the input digital video signal into an analog signal, and outputs the analog signal to a 75Ω driver 31. The 75Ω driver 31 supplies an analog video signal to the television monitor 4. TV monitor 4
Are designed to display an image based on an input video signal.

Next, the operation of the embodiment configured as described above will be described with reference to the timing chart of FIG. FIG. 3A shows the input of the memory 26, and FIG.
3B shows the input of the memory 27, and FIG. 3C shows the input of the photocoupler. 3D to 3F are enlarged views of the time axis of FIGS. 3A to 3C, respectively.

The insertion section 7 of the electronic endoscope 1 is inserted into a body cavity (not shown), and illumination light from the light source device 3 is guided into the body cavity by the light guide 6 to illuminate the subject. The light source device 3, for example, rotates the rotation filter once every three field periods, and sets R (red), R (red),
The illumination light of G (green) and B (blue) is emitted.

The reflected light from the subject is incident on the light receiving section of the CCD 5 provided at the tip of the insertion section 7 to form an optical image. CCD5 is a CCD driver 2 of the video processor 2.
Under the control of 1, the optical image of the subject is fetched in a plane-sequential manner and photoelectrically converted. That is, the CCD 5 performs exposure during the second half (exposure period) of the period (R field) during which the R illumination light is irradiated, and the first half (light-shield period) of the next field.
Are output from the output registers 36 and 37 through two channels. Similarly, the CCD 5 performs exposure during the latter half (exposure period) of the period during which the G and B illumination light is irradiated (R and B fields), and during the first half (light shield period) of the next field. The accumulated charges are output from the output registers 36 and 37 through two channels.

The two-channel video signal from the CCD 5 is supplied to the CDSs 22 and 23 of the video processor 2,
Double sampling and holding are separately performed for the channel and the B channel. The outputs of the CDSs 22 and 23 are converted into digital signals by A / D converters 24 and 25, respectively, and then supplied to memories 26 and 27. As shown in FIGS. 3A and 3B, the video signals of the A and B channels are input to the memories 26 and 27 during the light-shielding period in the first half of each field.

In the present embodiment, these A and B
As shown in FIG. 3C, the video signal of the channel is supplied to the photocoupler 28 during the light-shielding period and the exposure period of each field.

Now, as shown in FIGS. 3D and 3E,
During the light-shielding period, digital video signals A1, A2,.
, B-channel digital video signals B1, B2,... The memories 26 and 27 alternately output the A and B channel video signals to the photocoupler 28 in a predetermined data unit.

As shown in FIG. 3F, the photocoupler 2
8, video signals A1, B1, A2, A2,
B2,... Are time-division multiplexed and sequentially input. The photocoupler 28 supplies the video signal integrated into one system by the memories 26 and 27 to the signal processing circuit 29.

The video signal transmitted to the secondary circuit via the photocoupler 28 is subjected to white balance processing, gamma conversion processing, contour enhancement processing,
After predetermined signal processing such as GB synchronization processing is performed, D /
The analog signal is returned to the original analog signal by the A converter 30. D
The output of the / A converter 30 is output to the television monitor 4 via the 75Ω driver 31.

As described above, in the present embodiment, C
The CD 5 transfers the accumulated electric charges during the light-shielding period and stores them in the memories 26 and 27 for the A and B channels, and reads out from the memories 26 and 27 using the light-shielding period and the exposure period, whereby the A and B channels are read. Are time-division multiplexed into one system. This multiplex transmission makes it possible to reduce the number of photocouplers.

FIGS. 4 and 5 relate to a second embodiment of the present invention. FIG. 4 is a block diagram showing the second embodiment, and FIG. 5 is for explaining the operation of the second embodiment. 6 is a timing chart of FIG. 4, the same components as those in FIG. 1 are denoted by the same reference numerals, and description thereof will be omitted.

The present embodiment is provided in a patient circuit in a plane-sequential type electronic endoscope apparatus which sequentially illuminates with three color lights of red, green and blue and transfers electric charges in two channels during a light-shielding period. A low-speed photocoupler can be used by converting the frequency of a signal of two channels by a memory and transmitting the converted signal to a secondary circuit.

The present embodiment differs from the first embodiment in that the memories 26 and 27 are read out and two systems of photocouplers 41 and 42 are provided. The memories 26 and 27
The video signals of the A and B channels are written in the light-shielding period in the first half of each field. In the present embodiment, reading from the memories 26 and 27 is performed at half the speed of writing during the light-shielding period and the exposure period of each field. Photo coupler 41,
Reference numeral 42 supplies the video signals from the memories 26 and 27 to the signal processing circuit 29, respectively.

Next, the operation of the embodiment configured as described above will be described with reference to FIG. 5A shows an input of the memory 26, FIG. 5B shows an input of the memory 27, FIG. 5C shows an input of the photocoupler 41,
FIG. 5D shows the input of the photocoupler 42. FIGS. 5E to 5H are FIGS. 5A to 5D, respectively.
The time axis of FIG.

The driving method of the CCD 5 is the same as that of the first embodiment. The CCD 5 outputs the video signals of the A and B channels simultaneously. The video signals of these A and B channels are supplied to CDSs 22 and 23, respectively, and correlated double sampling is performed separately. After the video signals from the CDSs 22 and 23 are converted into digital signals by the A / D converters 24 and 25, as shown in FIG. 5A and FIG.
Written on 6,27.

Also in this embodiment, the memories 26 and 2
7 is performed during the light-shielding period and the exposure period of each field, and utilizing these periods, the photocoupler 4 is used.
1, 42. In the present embodiment, the speed of reading data from the memories 26 and 27 is different from that of the first embodiment.

The memories 26 and 27 are controlled by a memory controller (not shown) to perform reading at half the speed of writing. As shown in FIG. 5, the video signals A1 and A1 of the A and B channels are stored in memories 26 and 27, respectively.
, ... and B1, B2, ... shall be written respectively. The data amounts of the video signals A1, A2,..., B1, B2,.
It is constant as is clear from the time axis. Since the reading speed is 1/2 of the writing speed, as shown in FIGS. 5 (e) to 5 (h), each video signal is represented by A1, A2,.
, B2,... Are read out in twice the time of writing.

The video signals written in the memories 26 and 27 are read out and supplied to the photocouplers 41 and 42 using the light-shielding period and the exposure period of each field. The photocouplers 41 and 42 output the input A and B channel video signals to the signal processing circuit 29. The transmission rate of the video signal input to the photocouplers 41 and 42 is
This is half that of the first embodiment, and a low-speed photocoupler can be used.

Other operations are the same as those of the first embodiment.

As described above, in the present embodiment,
By writing the video signals of the A and B channels to the memories 26 and 27, respectively, and performing the frequency conversion with the reading speed lower than the writing speed, it is possible to use a low-speed photocoupler. Thereby, cost can be reduced.

By employing a multi-channel readout type of CCD 5 having a plurality of output registers and simultaneously reading out signal charges of a plurality of lines, the driving frequency is relatively low even when a high pixel CCD is used. It is possible to do. However, the cable length from the CCD to the video processor is relatively long, and the signal of each channel varies due to the variation of the cable. In addition, the FD provided for each channel can be
A (floating diffusion amplifier) varies.

Since such channel-to-channel variations appear as vertical stripes on a television monitor, these variations are corrected in a video processor.

The applicant of the present invention has previously filed Japanese Patent Application No. 9-91.
No. 056, in a device to which an endoscope equipped with a two-line readout CCD can be connected, white balance correction is performed, and at the same time, a level difference coefficient between channels is obtained.
An electronic endoscope apparatus that performs level difference correction between channels has been proposed.

The white balance must be corrected under predetermined conditions when the electronic endoscope is replaced. However, the operator sometimes forgets to perform the white balance correction when exchanging the electronic endoscope. In this case, the level difference between the two channels is not properly corrected, and as a result, vertical stripes appear on the screen, causing image quality deterioration.

FIG. 6 is a block diagram showing a modification of the electronic endoscope apparatus which facilitates such level difference correction.

In the electronic endoscope apparatus shown in FIG. 6, a memory for storing information for correcting a level difference between channels is provided in the electronic endoscope so that the level difference can be easily corrected. .

In FIG. 6, the electronic endoscope 51 differs from the electronic endoscope 1 of FIG. 1 in having a data ROM 52. The illustration of the light guide and the like is omitted. The video signals of the A and B channels from the CCD 5 of the electronic endoscope 51 are supplied to a video processor 53.

The data ROM 52 stores A, B from the CCD 5
The information for correcting the level difference between the two-channel video signals is held. For example, data ROM5
Stores variation data between channels, correction data of cables, and the like.

The video processor 53 has a CCD driver (not shown) having the same configuration as the CCD driver 21 shown in FIG. The CDSs 22 and 23 are the CDSs 22 and 2 in FIG.
In this configuration, the input A and B channel video signals are correlated double-sampled and output to GCA (gain control amplifiers) 54 and 55, respectively.

The GCAs 54 and 55 are controlled by the CPU 60,
The gains of the input A and B channel video signals are controlled and output to the WB correction circuits 56 and 57. The WB correction circuits 56 and 57 are controlled by the CPU 60,
After correcting the white balance of the input A and B channel video signals, the signals are output to the synthesizing circuit 58.

The synthesizing circuit 58 synthesizes the input two-channel video signals, converts them into one-system video signal, and outputs the signal to the signal processing circuit 59. The signal processing circuit 59 performs predetermined signal processing such as gamma conversion processing, contour enhancement processing, clamping processing, and 75Ω driver processing on the input video signal, and then outputs the processed video signal to the television monitor 4.
The television monitor 4 displays an image based on the input video signal.

The CPU 60 reads out the information stored in the data ROM 52 provided in the electronic endoscope 51, and controls the GCA 54, 55 and the WB correction circuits 56, 57 based on this information to thereby correct the white balance. And the level difference between the two channels can be corrected.

In the modified example configured as described above,
The light emitted from the light source device (not shown) is
The light is guided to a light guide (not shown) in 1 and illuminates the subject from the tip of the electronic endoscope 51. The CCD 5 is driven by a CCD driver (not shown) and outputs an electric signal corresponding to an optical image. In this case, similarly to the first embodiment, the CCD 5 outputs the accumulated charges of two lines to the video processor 53 as an A channel output and a B channel output.

The A and B channel video signals from the CCD 5 are correlated double-sampled by the CDS circuits 22 and 23. Further, the video signals of these two channels A and B are gain-adjusted in the GCAs 54 and 55, white-balance corrected in the WB correction circuits 56 and 57, and supplied to the synthesizing circuit 58.

In the present embodiment, these gain adjustment and white balance correction are performed by CPU 60
This is performed by reading the information of the OM 52. As the variation correction data stored in the data ROM 52, a signal ratio between channels, for example, (B channel signal level / A channel signal level) is used.

When the electronic endoscope 51 is connected to the video processor 2, the correction data stored in the data ROM 52 is transferred to the CPU 60 in the video processor 53, and the CPU 60 makes the GCA 54, 55 and WB correction according to the data. The circuits 56 and 57 are controlled to correct the variation between the A channel and the B channel.

The video signal whose variation has been corrected is supplied to the synthesizing circuit 5.
8, is combined with a video signal of one system, and is supplied to a signal processing circuit 59. The signal processing circuit 59 subjects the input video signal to signal processing such as gamma conversion processing, contour enhancement processing, clamping processing, and 75Ω driver processing, and then supplies the processed video signal to the TV monitor 4 to display an endoscope image. Let out.

As described above, in the present embodiment, the data ROM is provided in the electronic endoscope to store data for variation correction, read out by the CPU 60, and perform gain adjustment and white balance correction. Thus, it is possible to reliably obtain an endoscope image without vertical stripes in which variation between channels is corrected.

The correction data sets a certain reference value,
A correction value for the reference value may be used. For example, (A channel signal level / reference value), (B channel signal level /
(Reference value) may be stored as correction data. In this case, the correction value for the reference level is sent to the CPU to perform the variation correction, so that the variation correction between channels including the brightness can be performed by all the connected electronic endoscopes.

The signal processing circuits 29 and 59 shown in FIGS. 1 and 6 can also take in still images. However, if the input images input before and after the predetermined time match or mismatch, based on the determination result as to whether the image is a still image or a moving image, only a still image is captured,
A moving image may be erroneously determined as a still image, and a still image that is older in time may be output.

FIGS. 7 to 10 relate to an electronic endoscope apparatus which addresses such a problem. FIG. 7 is a block diagram showing the electronic endoscope apparatus, and FIG. 8 is an image in a display control circuit in FIG. FIG. 9 is a block diagram showing the configuration of the freeze processing device, FIG. 9 is a flowchart for explaining the operation thereof, and FIG. 10 is a block diagram showing another example of the image freeze processing device.

In FIG. 7, the insertion portion 6 of the electronic endoscope 61
A solid-state image pickup device 64 constituted by a CCD is arranged at an image forming position of the objective lens 63 at the front end of the device 2. An illumination light guide 65 for irradiating the subject with illumination light is also provided in the insertion section 62.

The illumination light guide 65 includes a light source section 66.
Illumination light that has passed through a rotating RGB filter 68 that is driven to rotate at a constant speed by a motor (not shown) is guided from a light source lamp 67 disposed therein.

The video signal processing section 69 is for performing image pickup in a frame sequential system. The pre-processing circuit 70 and the CCD driving circuit 75 in the video signal processing unit 69 are connected to the solid-state imaging device 64 in the insertion unit 62 via a connector 77.

The control signal generating circuit 76 generates a timing signal for controlling each circuit and supplies it to each circuit section. The CCD drive circuit 75 generates a drive signal for driving the solid-state imaging device 64 based on a signal from the control signal generation circuit 76.

The solid-state imaging device 64 includes a CCD driving circuit 75
, And photoelectrically converts an optical image from a subject to output video signal data. The video data is input to a pre-processing circuit 70, subjected to predetermined processing such as amplification and waveform shaping, and then digitized by an A / D converter 71.

The video signal from the A / D converter 71 is supplied to the synchronization control circuit 72. The synchronization control circuit 72 performs the synchronization processing of the frame-sequential signal, and then outputs the signal to the display control circuit 73. The display control circuit 73 has an image freeze processing device shown in FIG. 8, performs predetermined display processing including image freeze processing on the input video signal, and performs D / A conversion by the D / A converter 7.
4 is output.

FIG. 8 shows a specific configuration of the display control circuit 73.

In FIG. 8, a delay memory 81 delays an input video signal from the synchronization control circuit 72 for a predetermined period and supplies the delayed video signal to the still picture memories 82 and 83. Motion detection circuit 84
Detects the motion of the sequentially input video signal, and outputs a motion detection signal indicating the motion amount of the subject to the minimum value detection circuit 85.

The minimum value detection period instruction circuit 86 outputs an instruction signal for instructing a predetermined minimum value detection period to the minimum value detection circuit 85. The minimum value detection circuit 85 is instructed by the minimum value detection period instruction circuit 86 for the minimum value detection period, and detects the minimum value of the motion amount from the motion detection circuit 111 in the minimum value detection period. The minimum value detection circuit 85 outputs a detection signal to the memory control circuit 87 when the minimum value detection period starts and when the minimum value is detected. Note that the minimum value detection period instruction circuit 86 is provided in the still image memory 8.
Different periods are designated as the minimum value detection periods for 2,83.

The memory control circuit 87 includes the minimum value detection circuit 8
5, the still image memory 82,
The writing operation of the input image signal from the delay memory 81 to the still image memory 83 is controlled. That is, the input image signals from the delay memory 81 are written into the still image memories 82 and 83 at the start of the minimum value detection period and at the time of detection of the minimum value, respectively.

The freeze instruction circuit 88 supplies a freeze instruction signal based on a user operation to the memory control circuit 87. When the freeze control signal is input, the memory control circuit 87 reads and outputs the image signal with the smaller amount of motion among the image signals written in the still image memory 82 and the still image memory 83, The reading of the still image memories 82 and 83 is controlled.

The image signals from the still image memories 82 and 83 are supplied to the D / A converter 74 shown in FIG. The D / A converter 74 converts the input digital signal into an analog signal and supplies the analog signal to the television monitor 4 via the connector 78. The television monitor 4 displays a subject image based on the input image signal.

Next, the operation of the thus configured electronic endoscope apparatus will be described with reference to FIG. FIG. 9 (a)
9 shows a synchronized output image signal, and FIG. 9B shows a delayed memory output image signal. FIGS. 9C to 9E show the minimum image detection period signal, the memory update signal, and the in-memory image signal for the still image memory 82, respectively. FIGS. 9F to 9H show the minimum value detection period signal, the memory update signal, and the in-memory image signal for the still image memory 83, respectively. In FIG.
An image signal is indicated by a combination of A to E and a numeral. A to E indicate the magnitude of the motion amount, and A, B,
.. Indicate that the amount of motion sequentially increases in the order of C,. The numbers are numbers assigned in the order of input.

The image signal from the solid-state imaging device 64 is supplied to a pre-processing circuit 70, where a predetermined process such as amplification and waveform shaping is performed. The output of the pre-processing circuit 70 is
After being digitized by the A / D converter 71, it is synchronized by the synchronization control circuit 72 to be displayed by the display control circuit 73.
Is input to

The delay memory 81 of the image freeze processing device in the display control circuit 73 delays the input image signal by one field period or one frame period. The delay amount is one image signal (one field or one frame) period for detecting the amount of movement of the subject. This is because the still image memories 82 and 83 are controlled by a memory update signal shown in FIGS. 9D and 9G from the memory control circuit 87 after the motion amount is detected. This is to correct the delay of the update signal.

The input image signal is sequentially transferred to the motion detection circuit 8.
4 and the amount of movement of the subject is detected. For example, the motion detection circuit 84 detects the amount of motion of the subject based on the cross-correlation of each primary color signal. For example, the difference between the pixels of any two primary color signals in one field is calculated, and the accumulated value of the absolute value of the difference is detected as the motion amount. The motion detection signal is supplied to the minimum value detection circuit 85.

The minimum value detection period instruction circuit 86 outputs an instruction signal for instructing a predetermined minimum value detection period to the minimum value detection circuit 85. In this case, the minimum value detection period instruction circuit 86 generates a minimum value detection period signal indicating different minimum value detection periods for the still image memories 82 and 83.

The minimum value detection circuit 85 detects the minimum value of each motion amount from the motion detection circuit 84 during the instructed minimum value detection period, and detects the minimum value at the start of the minimum value detection period. , And outputs a detection signal to the memory control circuit 87. When the detection signal from the minimum value detection circuit 85 is input, the memory control circuit 87 supplies a memory update signal to the still image memories 82 and 83, and outputs the input image signal from the delay memory 81 to the still image memories 82 and 83. Write 83.

As shown in FIGS. 9C, 9D, 9F, and 9G, the memory update signal is generated at the start of the minimum value detection period and at the time of minimum value detection. As a result, each time an image signal with a minimum amount of motion is detected within the minimum value detection period, writing to the still image memories 82 and 83 is performed.

Since the periods during which the minimum value of the amount of movement of the subject is detected are different, each of the still image memories 82 and 83 has
As shown in (e) and (h), different image signals are written.

When the freeze instruction signal is input to the memory control circuit 87 by the freeze instruction circuit 88, the image signals written in the still image memories 82 and 83
The image signal with the smaller amount of motion is output.

For example, when the operator gives a freeze instruction at the timing indicated by the mark ▼ in FIG. 9, the still image memories 82 and 83
Write control is not performed, and the in-memory image signal C written in the still image memories 82 and 83 at that time.
7 and A4, the in-memory image signal A4 having a small amount of motion.
Is read out from the image memory 83 and output.

As described above, in the example of FIG. 8, the minimum value of the motion amount is detected within the predetermined minimum value detection period, and the image is stored at the start of the minimum value detection period and at the time of the minimum value detection. In addition, a still image with the least color shift near the freeze execution can be output without a time delay.

FIG. 1 shows an image freeze processing apparatus.
A configuration of 0 is also conceivable. 10, the same components as those in FIG. 8 are denoted by the same reference numerals, and description thereof will be omitted.

The configuration of FIG. 10 differs from the configuration of FIG. 8 in that an output image switching circuit 89 is added. Output image switching circuit 89
Outputs a switching signal to the memory control circuit 87 to control which of the still image memories 82 and 83 is to be read.

Thus, it is possible to switch between outputting an image signal with the minimum amount of movement of the subject or outputting an image signal near the freeze execution.

In the electronic endoscope apparatus configured as described above, the memory control circuit 87 receives not only the result of minimum value detection but also the switching signal from the output image switching circuit 89 to output the signals from the still image memories 82 and 83. Controls reading. That is, when a freeze instruction signal is supplied to the memory control circuit 87 by the freeze instruction circuit 88, the memory control circuit 87 first writes into the still image memories 82 and 83 based on the switching signal from the output image switching circuit 89. One of the image signals is read out and output.

That is, the switching control of whether to output an image signal with a small amount of motion or an image signal in the vicinity of the execution of the freeze is performed by the switching signal of the output image switching circuit 89.

For example, it is assumed that the operator issues a freeze instruction at the timing indicated by the symbol ▼ shown in FIG. 9A. Then, the writing control to the still image memory is not performed, and at that time, the image signal specified by the switching signal among the in-memory image signals C7 and A4 written in the still image memory 82 and the still image memory 83 is output. You. That is, when the switching signal instructs to output an image signal with little color shift, the in-memory image signal A
4 is read and output, and when it is instructed to output an image signal in the vicinity of execution of the freeze, the image signal C in the memory is output.
Read and output 7.

Of course, the still image output can be switched any number of times until the freeze instruction command is released.

As described above, in the example of FIG. 10, the same effect as that of the example of FIG. 8 is obtained, and the operator can select and output a desired still image.

Note that the configuration shown in FIGS. 8 and 10 is applicable to both the NTSC and PAL image signals.
Obviously it is applicable.

Incidentally, in a frame sequential imaging apparatus, a color shift which is a defect of color reproducibility caused by a difference in sampling time of color information may occur.

FIGS. 11 to 15 show a configuration for reducing such a color shift in a moving image. FIG. 11 is a block diagram showing the configuration of the electronic endoscope device, and FIG.
1 is a block diagram showing a specific configuration of the synchronization circuit, FIG. 13 is a timing chart for explaining the operation of the memory shown in FIG. 12, and FIGS. 14 and 15 are tables for explaining the operation. 11, the same components as those in FIG. 8 are denoted by the same reference numerals, and description thereof will be omitted.

The electronic endoscope apparatus shown in FIG. 11 has a video signal processing unit 101. The video signal processing unit 101 is
The configurations of the reduction circuit 102 and the synchronization circuit 103 are different from those of the video signal processing unit 69 in FIG.

The digital video signal from the A / D converter 71 is supplied to an enlargement / reduction circuit 102. The enlargement / reduction circuit 102 performs enlargement / reduction processing on the input video signal, and outputs the result to the synchronization circuit 103. The synchronization circuit 103 synchronizes the input video signal with an RGB signal.

FIG. 12 shows a specific configuration of the synchronization circuit 103. In FIG. 12, an enlargement / reduction circuit 102
Video signals from the R memory 112, G memory 113, B
Memory 114, delay memory 115 and delay memory 116
Supplied to The R, G, and B memories 112 to 114 hold the input frame-sequential video signals for each of the R, G, and B colors and output them at the same time.

The delay memory 115 of the color shift reducing circuit 98
Delays the input frame sequential video signal by one field period and outputs the same, and the delay memory 116 delays the input frame sequential video signal by four field periods and outputs it. The outputs of the delay memories 115 and 116 are supplied to a subtractor 94.
The subtractor 94 obtains the difference between the frame sequential video signals before and after the three-field period and outputs the difference to the multipliers 95 to 97. Multiplier 9
Coefficients are given to 5 to 97, respectively, and multipliers 95 to 9
7 multiplies these coefficients by the output of the subtractor 94,
The data is output to the adders 91 to 93. The adders 91 to 93 add the outputs of the R, G, B memories 112 to 114 and the outputs of the multipliers 95 to 97, respectively, and output the result to the display control circuit 73.

In the synchronizing circuit thus constructed, the memory 1 for synchronizing the frame-sequential video signal output from the enlarging / reducing circuit 102 with R, G, B signals.
12 to 114 are input. In this case, the frame-sequential R, G, and B signals are separately written into the R memory 112, the G memory 113, and the B memory 114. Memory 112
From 114 to 114, video signals for each color are synchronized and output.

On the other hand, the frame sequential signal from the enlargement / reduction circuit 102 is delayed by one field period by the delay memory 115 of the color misregistration reducing circuit 98 for reducing color misregistration. Similarly, the frame sequential signal is
Field period is delayed. Delay memories 115 and 116
Is output to the subtractor 94, and the difference between the frame sequential signals of the same color before and after the three-field period, that is, the motion amount for each color is obtained. This difference is multiplied by multipliers 95 to 97 with specific coefficients different for each of the RGB fields.

FIG. 14 shows this coefficient. Subtractor 9
At the timing when the red difference is output from 4, the multipliers 95 to 97 multiply the coefficients by 0, d, and f, respectively. When the green difference is output from the subtractor 94, the multipliers 95 to 97 , Are multiplied by coefficients a, 0, and e, respectively. At the timing when the blue difference is output from the subtractor 94, the multipliers 95 to 97 multiply the coefficients b, c, and 0, respectively.

When the images are captured in a frame-sequential manner, the captured images of RGB differ in time series, and the field data of each color is updated every three fields. That is, since each color is not updated during three fields, a color shift phenomenon occurs when a fast-moving subject is imaged.

Therefore, the color shift reduction circuit 98 obtains the amount of motion for each color for each field, multiplies the obtained amount of motion for the other color by a coefficient, and multiplies the luminance level corresponding to the color motion by a multiplier 95. Through 97. The outputs of the multipliers 95 to 97 are added to the synchronized R, G, B signals. That is, R,
The outputs of the multipliers 95 to 97 are added to the R, G, B signals synchronized and output from the G, B memories 112 to 114 to obtain R, G, B signals with corrected color shift.

Next, a specific example will be described with reference to FIG.

The image data input from the enlargement / reduction circuit 102 is a single-color frame (image data) of R, G, and B, and image data of odd fields and even fields are mixed. The image data of Rn, Gn, and Bn is selected for each field in ascending order of the suffix n by a write chip select controller (not shown), and the data is cyclically repeated. The image data is distributed to the R, G, and B memory banks and written to the frame memory.

On the other hand, reading from the frame memory
The read chip select controller (not shown) controls the reading of field data from the field immediately after the writing to three consecutive fields. In this case, the data of the field that matches the field information of the video synchronization signal is read in consideration of the interlaced display.

The color shift reducing circuit 98 includes the memories 115 and 1
The subtracter 94 calculates the difference between the data obtained by delaying the field sequential signal by one field period and the data obtained by delaying the field sequential signal by four field periods. In this case, the field to be read is a field that matches the field information of the video synchronization signal, as described above.

As a result, the same colors of R, G, and B
The amount of motion before and after the memory update is extracted for each field. By adding this amount of motion to the amount of motion of each color component, it is possible to update the R, G, and B signals for each field instead of the conventional three fields.

For example, the R signal will be described. FIG.
In the fourth frame in, the red frame data of the frame sequential data is written to the R memory 112. In the fifth frame, the outputs of the delay memories 115 and 116 are R1 and R1, respectively.
R0, and the difference Δ = R1−R0 is output from the subtractor 94. Since the multiplication coefficient in this case is 0 as shown in FIG. 14, the corrected data of the R memory output is R
It remains unchanged at 1.

Next, in the sixth frame, the delay memory 1
The difference between 15, 116 is Δ = G1−G0. Since the multiplication coefficient at this time is a, the corrected data of the output of the R memory 112 is (R1 + aΔ). Next, in the seventh frame, the difference between the delay memories 115 and 116 is Δ = B1−B0.
Becomes Since the multiplication coefficient at this time is b, the R memory 1
The corrected data of 12 outputs is R1 + bΔ.

As described above, even in a field in which conventional data is not updated, the amount of motion of another updated color can be detected, and data can be updated for each field by adding only the amount of motion. Thus, color shift can be reduced.

Although the operation has been described for the R signal,
The same applies to the G and B signals.

Although the display method of the interlace method has been described as an example, it is apparent that the present invention can be similarly applied to the display method of the non-interlace method.

Further, an example shown in FIG. 15 can be considered as a coefficient to be given to the multipliers 95 to 97. That is, the relationship between the type of the motion amount and the multiplication coefficient for correction is as shown in the table of FIG.

FIG. 15 is a table summarizing coefficients to be multiplied by the color shift motion amount △. The value multiplied by this coefficient is added to the output of the synchronization memory. As shown in FIG. 15, for example, the multiplication coefficient of the component added to the B memory output for the R motion amount ΔR and the multiplication coefficient of the component added to the R memory output for the B motion amount ΔB are Is in a reciprocal relationship. This takes into account that the ratio of the imaging gain of each color of R, G, and B to the imaging gain of another color is constant.

By using such coefficients, the factors to be considered as multiplication coefficients are RG (coefficient: a) and RB
The gain relationship may be determined for three combinations of (coefficient: b) and GB (coefficient: c).

[Supplementary Notes] (1) Driving means for accumulating electric charges based on an optical image in a solid-state image sensor in an exposure period, reading out electric charges accumulated in a light-shielding period through a plurality of channels, and outputting as a video signal; A plurality of storage means provided respectively to hold video signals of a plurality of channels from the solid-state imaging device,
By performing readout from the plurality of storage units during the exposure period and the light-shielding period, the video signals of the plurality of channels are time-division multiplexed or frequency-converted to be electrically isolated from the patient circuit. An electronic endoscope apparatus comprising: a reading unit that outputs a signal to a circuit.

(2) A light source device for irradiating and shielding the subject image with illumination light using an RGB rotation filter, a driving circuit for a solid-state image sensor for reading a video signal from the solid-state image sensor during a light-shielding period, and storing the video signal An electronic endoscope device having a memory means in a patient circuit for transmitting a signal to a secondary circuit after frequency conversion of a video signal is performed by the memory means.

(3) a plurality of memory means in the patient circuit for storing video signals read from the plurality of horizontal transfer paths;
An electronic endoscope device for transmitting a signal to a secondary circuit after performing frequency conversion and time division multiplexing by the plurality of memory means.

(4) An electronic endoscope having a plurality of horizontal transfer paths and having a solid-state image pickup device at the tip for outputting a plurality of video signals, and a detachable electronic endoscope for signal processing of video signals. In the electronic endoscope apparatus to perform, the electronic endoscope apparatus has gain adjustment means for adjusting the gains of a plurality of video signals output from the electronic endoscope, and controls the gain of the plurality of gain adjustment means. An electronic endoscope apparatus, wherein a storage means for holding information to be performed is provided in the electronic endoscope.

(Background of Supplementary Item 4) (Prior Art) In recent years, endoscopes have been widely used for diagnosis in the medical field, treatment using a treatment tool, and the like. Further, various types of electronic endoscopes using an image pickup device such as a charge-coupled device (CCD) as an image pickup means are also used.

The electronic endoscope device includes the electronic endoscope, a light source device for supplying illumination light to the endoscope, a video processor for obtaining a video signal of a subject image by the imaging means, and an image of the video processor. And a television monitor for displaying signals.

In recent years, a high-pixel CCD has been used as an imaging means of an electronic endoscope, and the driving frequency has been increased.

For this reason, some CCDs have a plurality of horizontal transfer registers, and read signal charges of a plurality of lines at the same time to lower the driving frequency. In this case, the video signals read at the same time are subjected to variation correction between channels and filter processing in the video processor and restored.

In the electronic endoscope, since the CCD serving as the image pickup means is located at the end of the endoscope, the cable for driving the CCD and the cable for transmitting the output signal of the CCD are long.
Therefore, in the case of a CCD having a plurality of channels, there is a problem of cable variation between the channels. In addition, even a single CCD has an FDA (floating diffusion amplifier) for each channel, which varies. Since variations between channels appear as vertical stripes on a television monitor, a process of correcting this in a video processor is required.

The applicant of the present application has disclosed in Japanese Patent Application No.
In an electronic endoscope apparatus to which an endoscope equipped with a line readout CCD can be connected, an electronic endoscope apparatus which performs white balance correction, obtains a level difference coefficient between channels, and corrects a level difference between channels. Has been proposed.

(Problems to be Solved by the Invention (Purpose))
Individual differences in electronic endoscopes (variation between CCD channels,
Correcting vertical stripes or gain variations caused by cable variations) to obtain high-quality endoscopic images.

(Means and Actions for Solving the Problems) In the conventional electronic endoscope apparatus, when performing white balance correction, the end of the endoscope is inserted into a white balance correction cylinder having a white inside. In addition, white balance correction is performed by an operation switch or the like under an appropriate illumination light amount.

However, if white balance correction is forgotten when replacing the electronic endoscope or white balance correction is performed under inappropriate conditions such as insufficient illumination light amount, the level difference correction is not performed properly, and Appears as vertical stripes on the screen, causing image quality degradation.

According to the present invention, an electronic endoscope having a plurality of horizontal transfer paths and having a CCD for outputting video signals of a plurality of systems at its tip, and an electronic endoscope which is detachable and performs signal processing of video signals. In the electronic endoscope apparatus, storage means for holding information for performing gain control of a plurality of gain adjustment means is provided in the electronic endoscope, and gain correction is performed in the electronic endoscope apparatus based on information from the storage means. Is performed, the variation between channels is corrected.

(5) First image storage means for storing an input image signal obtained by photoelectric conversion means for obtaining an image signal by photoelectrically converting a subject image formed by an imaging optical system; An electronic device including an image freeze processing device including: a motion detecting unit that detects a moving amount of a subject from an image signal; and a still image instruction unit that issues a still image instruction signal for storing a still image in the first image storage unit. In the endoscope apparatus, a second image storage unit that stores the input image signal connected in parallel with the first image storage unit, and a motion amount output from the motion detection unit can be determined within different predetermined times. Minimum value detection means for detecting and outputting the minimum value of the amount of movement, minimum value detection period instruction means for instructing the minimum value detection means to reset a minimum value at the start of each of the detection periods, In accordance with the output of the minimum value detection means, the storage operation of the input image signal to the first and second image storage means is controlled, activated by a still image instruction signal from the still image instruction means, Image storage / output control for controlling the output of a still image from the image storage unit storing the input image signal with a small amount of movement of the subject in the input image signals stored in the first and second image storage units Electronic endoscope apparatus comprising:

(6) An output image switching means capable of switching output control of one of the image signals stored in the first and second image storage means, respectively. An electronic endoscope device according to claim 1.

(Background of Additional Items 5 and 6) (Prior Art) JP-B-8-13302 is a prior art of an electronic endoscope apparatus in which color shift is reduced.

(Problem to be Solved by the Invention) Tokuho 8
The problem of the -13302 publication is that, in the process of storing a still image with a small color shift in the storage means, a match between the input image and the input image delayed by a predetermined time, a mismatch between the still image and the moving image, Since the image determined to be a still image is stored and updated in the storage means, if they match, even if the amount of movement of the subject is larger than the image signal stored in the storage means, the image is determined to be a still image and the storage in the storage means is updated. Since the still image determination based on the match and mismatch is performed, the image signal in the vicinity where the operator executes the freeze cannot be reliably obtained as a still image, and a still image that is considerably older in time is output. It is possible that

(Purpose) An object of the present invention is to obtain an image signal without color shift near a freeze as a still image.
The amount of motion of the subject is stored in separate image storage means for each of the image signals in which the amount of motion of the subject is minimized in a certain different minimum value detection period, and the operator issues a freeze instruction command to obtain a still image. Upon execution, an image signal having a small color shift (a minimum amount of movement of the subject) among the image signals stored in the separate image storage means is output from the image storage means immediately after execution of the freeze instruction command.

Another object is to store image signals in which the amount of movement of the subject is minimum in different different minimum value detection periods in separate image storage means so that the operator can obtain a still image. When the freeze instruction command is executed, the operator can set which of the image signals stored in the separate image storage means is to be output, and the set image is switched and output from the image storage means. is there.

(7) Image pickup means for picking up an image of a subject sequentially illuminated with illumination light of different wavelengths, first storage means for storing the sequentially picked up image signals by color and outputting them simultaneously, and Second storage means for selecting an odd or even field image from the obtained image signals or outputting a frame-sequential image as a frame image, and outputting the sequentially captured image signal to the second storage means A third storage unit for outputting the field image at least one cycle prior to the frame sequential cycle with the illumination light of the same color as the captured image, and an operation on the output of the first to third storage units In an electronic endoscope apparatus having an arithmetic unit capable of performing the following operations, the amount of motion of the same color image data is reduced for each field by subtracting the output of the third storage unit from the second storage unit. Alternatively, the electronic endoscope apparatus is characterized in that it is calculated for each frame, and a result obtained by multiplying this value by a different coefficient for each color is added to the output of the first storage means of a color different from the same color.

(Background of Additional Item 7) (Prior Art) In recent years, as a means for observing a diseased part or the like in a living body, an electronic endoscope using a solid-state imaging device such as a CCD as an imaging means has been widely used. . In addition, the electronic endoscope sequentially illuminates the subject with illumination light of different wavelengths such as red, green, and blue, and screens respectively captured under illumination of each wavelength;
That is, there is a plane sequential electronic endoscope that obtains a color image by synthesizing component images. In such a plane-sequential imaging device, compared to a simultaneous imaging device in which a mosaic color filter is arranged in front of an imaging surface of a solid-state imaging device using white light as illumination light, imaging of the solid-state imaging device in one wavelength region is performed. There is an advantage that the number of cells is large and therefore the resolution of the imaging screen is good.

However, in the above-mentioned frame sequential method, in order to obtain an image of one color image, color images of components having different imaging times are synthesized. For this reason, if there is a relative movement between the moving subject or the imaging unit and the subject, the combined color image differs from the original color of the subject. Such a defect, that is, a defect in color reproducibility caused by a difference in sampling time of each color information is referred to as a color shift. The color shift may be caused not only by the above-described movement but also by, for example, zooming.

In order to solve the above-mentioned problems, for example, in Japanese Patent Laid-Open No. 9-102958, means for attenuating the output signal level of the image signal for each color to 1/3, 2/3, 3/3,
Means are provided for attenuating the output signal level of the image signal three fields before to 3/3, 2/3, and 1/3.
Each color signal obtained only for each field can be obtained as if it were a signal corresponding to each field.

(Problems and Object to be Solved by the Invention)
However, this proposal merely interpolates video data updated every three fields for each color in a time-series manner, and does not reflect the actual movement of image data.

The present invention focuses on this point, and aims to reduce the color shift of a moving image by reflecting the motion amount of each color detected by a frame signal in a frame sequence in all RGB frame sequential video signals. .

(Means for Solving the Problems and Functions and Effects) The electronic endoscope apparatus according to the present invention comprises: an image pickup means for picking up an image of a subject sequentially illuminated by illumination light of different wavelength ranges; First to store signals for each color and output them simultaneously
A second storage means for selecting any of the odd and even field images from the sequentially captured image signals or outputting a frame sequential image as a frame image; and storing the sequentially captured image signals A third storage unit for outputting the field image that is at least one cycle prior to the frame sequential cycle with the illumination light of the same color as the output of the second storage unit and that of the captured image, and the first to third fields In an endoscope imaging apparatus including an arithmetic unit capable of performing an arithmetic operation on the output of the storage unit, the amount of motion of imaging data of the same color by subtracting the output of the third storage unit from the second storage unit Is calculated for each field or each frame,
The result of multiplying this value by a different coefficient for each color is added to the output of the first storage means of a color different from the same color.

In the present invention, the difference between the RGB signal synchronized by the synchronizing means and the video signal of the same color before any of the RGB plane-sequential signals captured as the plane-sequential signal is updated is detected. Then, the difference is multiplied by a specific coefficient, and the difference is added to the other unsynchronized two-color synchronized signals.

[0145]

As described above, according to the present invention, the number of isolation elements between the patient circuit and the secondary circuit is reduced, and the operating frequency of the isolation elements is reduced, so that cost and current consumption are reduced. Has the effect of being able to reduce.

[Brief description of the drawings]

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

FIG. 2 is an explanatory diagram showing reading from a CCD.

FIG. 3 is a flowchart for explaining the operation of the first embodiment.

FIG. 4 is a block diagram showing a second embodiment.

FIG. 5 is a timing chart for explaining the operation of the second embodiment.

FIG. 6 is a block diagram showing a modification of the electronic endoscope apparatus which facilitates level difference correction.

FIG. 7 is a block diagram showing another electronic endoscope apparatus.

FIG. 8 is a block diagram showing a configuration of an image freeze processing device in the display control circuit in FIG. 7;

FIG. 9 is a flowchart for explaining the operation of the electronic endoscope apparatus of FIG. 7;

FIG. 10 is a block diagram showing another example of the image freeze processing device.

FIG. 11 is a block diagram showing a configuration of another electronic endoscope device.

FIG. 12 is a block diagram showing a specific configuration of a synchronization circuit in FIG. 11;

FIG. 13 is a flowchart for explaining the operation of the electronic endoscope in FIG. 11;

FIG. 14 is a chart for explaining the operation of the electronic endoscope apparatus of FIG. 11;

FIG. 15 is a chart for explaining the operation of the electronic endoscope apparatus of FIG. 11;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Electronic endoscope, 2 ... Video processor, 3 ... Light source device, 5 ... CCD, 26, 27 ... Memory, 28 ... Photocoupler

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme court ゛ (Reference) H04N 7/18 H04N 7/18 M 5C065 9/04 9/04 Z (72) Inventor Hirotaka Hara Shibuya, Tokyo 2-43-2 Hatagaya-ku, Olympus Optical Industrial Co., Ltd. (72) Inventor Kazunari Nakamura 2-43-2 Hatagaya, Shibuya-ku, Tokyo Olympus Optical Industrial Co., Ltd. (72) Inventor Yasuo Komatsu Tokyo 2-43-2 Hatagaya, Shibuya-ku Olympus Optical Industrial Co., Ltd. (72) Inventor Fumiyuki Okawa 2-43-2 Hatagaya, Shibuya-ku, Tokyo Olympus Optical Industrial Co., Ltd. F-term (reference) 2H040 AA00 BA00 CA04 CA09 CA11 DA03 DA15 DA22 GA02 GA05 GA06 GA10 GA12 4C061 AA00 BB02 CC06 DD00 JJ12 JJ17 LL02 MM03 NN01 NN03 NN05 SS03 SS10 SS11 SS30 UU05 UU10 WW01 5C022 A A08 AB00 AC03 AC42 AC69 5C024 AA01 BA03 CA23 FA01 GA11 HA00 HA10 HA14 HA24 5C054 AA09 DA06 EA01 EA03 FB03 GA04 HA12 5C065 AA04 BB48 DD02 GG18 GG30 GG50

Claims (1)

[Claims] 1. A driving means for accumulating electric charges based on an optical image in a solid-state imaging device during an exposure period, reading out the electric charges accumulated during a light-shielding period by a plurality of channels, and outputting as a video signal, and provided in a patient circuit. A plurality of storage means for respectively holding a plurality of channels of video signals from the solid-state imaging device; and reading out from the plurality of storage means during the exposure period and the light blocking period, thereby time-division multiplexing the plurality of channel video signals. An electronic endoscope apparatus comprising: a readout unit for performing a frequency conversion or a frequency conversion and outputting the converted signal to a secondary circuit which is electrically insulated from the patient circuit.