JPH06327627A - Electronic endoscope equipment - Google Patents

Abstract

PURPOSE:To provide an electronic endoscope equipment capable of distinguishing differences in image pickup systems of an electronic endoscope without comprising a special terminal or the like for transmission of identification information. CONSTITUTION:In an electronic endoscope equipment 1 comprising an electronic endoscope 2 provided with a CCD 25 as an image pickup means at a front-end portion of an inserting portion and a video processor 3 to which this electronic endoscope 2 is connected, the video processor 3 extracts a carrier component from an output signal of the CCD 25. The electronic endoscope equipment 1 is also provided with a system distinguishing circuit 36 for distinguishing whether the image pickup system of the electronic endoscope 2 is a plane sequential system or a synchronous system according to the size of the carrier component, and further comprises: a CCD distinguishing means 31 for distinguishing the kind according to a value calculated by detecting the image portion of a signal outputted from the CCD 25, and a freeze circuit for freezing by detecting the amount of an image blur according to the high frequency component of the image signal.

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 having a solid-state image pickup device as an image pickup means.

[0002]

2. Description of the Related Art Conventionally, various types of electronic endoscope apparatus having a solid-state image pickup device as an image pickup means have been proposed, and an example of a frame sequential electronic endoscope apparatus is shown in FIG.
Will be described with reference to. In the video processor 103,
A lamp that emits a wide range of light from ultraviolet light to infrared light 1
As the lamp 123, a general xenon lamp, a strobe lamp, or the like can be used. These xenon lamps and strobe lamps
This is because a large amount of ultraviolet light and infrared light are emitted as well as visible light. Electric power is supplied to the lamp 123 from the power supply unit 122.

A rotary filter 129, which is rotationally driven by a motor 128, is arranged in the light emitting direction of the lamp 123. The rotary filter 129 is a filter in which light for each wavelength region of red (R), green (G), and blue (B) for normal observation is transmitted and is arrayed along the circumferential direction. Further, the motor 128 has a motor driver 139.
The rotation is controlled and driven by.

After passing through the rotary filter 129, R,
The light separated in time series into the light of each wavelength region of G and B is
The light is incident on the incident end of the light guide 121. The light guide 121 that transmits this illumination light is arranged by inserting the universal cord connected to the video processor 103 through the connector through the insertion portion 109 of the electronic endoscope 102, and the tip surface thereof is the insertion portion. The tip 11 of 109
It is located at 3. Then, the transmitted illumination light is emitted from the tip 113 toward the subject to illuminate the observation site.

The return light from the observation site due to the illumination light is imaged by the objective lens system 124 on the solid-state image pickup device 125 arranged at the image formation position and photoelectrically converted. The solid-state image sensor 125 has sensitivity in a wide wavelength range from the ultraviolet region to the infrared region including the visible region.

A drive pulse from a driver circuit 131 in the video processor 103 is supplied to the solid-state image pickup device 125 via a signal line 126 inserted into the insertion portion 109 and the universal cord and connected to the connector. Is applied, and reading and transfer are performed by this drive pulse.

On the other hand, the image signal read out from the solid-state image pickup device 125 is in the video processor 103 through a signal line 127 which is inserted into the insertion portion 109 and the universal cord and connected to the connector. Alternatively, the preamplifier 13 provided in the electronic endoscope 102
2 (in FIG. 11, the case provided in the video processor 103 is shown as an example). The image signal amplified by the preamplifier 132 is input to the process circuit 133, subjected to signal processing such as γ correction and white balance, and converted into a digital signal by the A / D converter 134.

This digital image signal is, for example, red (R), green (G), blue (B) by the selection circuit 135.
The colors are selectively stored in the first memory 136a, the second memory 136b, and the third memory 136c corresponding to the respective colors. The first memory 136a, the second memory 136b, and the third memory 136c are read simultaneously, converted into analog signals by the D / A converter 137, and output as R, G, B color signals, and
It is input to the encoder 138 and output as an NTSC composite signal from the encoder 138, and the observed region is displayed in color by, for example, a color monitor.

In addition, a timing generator 142 for generating the timing of the entire system is provided in the video processor 103, and the timing generator 142 synchronizes the circuits of the motor driver 139 and the driver circuit 131. .

In addition to the above-mentioned frame sequential type as an electronic endoscope apparatus, for example, white light is irradiated to a subject through a light guide without providing a rotary filter inside the light source device, and a subject image is picked up by an image pickup device. There is a simultaneous electronic endoscope apparatus that performs color image pickup by a color filter array provided on the front surface of the image pickup plane, and performs color separation in a video processor for processing.

By the way, there are electronic endoscopes connected to a video processor that use various image pickup devices. Since these image pickup devices have different driving methods and a different number of pixels, they are optimal for that image pickup device. Different driving methods and signal processing must be applied. Further, the driving method of the image pickup device and the processing method of the image pickup signal must be changed depending on whether the electronic endoscope system is the frame sequential system or the simultaneous system.

In the conventional electronic endoscope apparatus as described above, a means for generating identification information is provided between the electronic endoscope and the video processor in order to determine the difference between the image pickup device and the image pickup method. Then, the driving method and the signal processing method on the video processor side are controlled by the identification information.

[0013]

However, in the above-mentioned conventional electronic endoscope apparatus, a terminal or the like is required as means for transmitting discrimination information between the electronic endoscope and the video processor, and this configuration is also required. However, since there is a limit to the amount of information that can be discriminated, there is a problem that the discrimination cannot be performed when more image pickup devices or the like are adopted.

The present invention has been made in view of the above problems, and an electronic endoscope capable of discriminating the difference in the image pickup method of the electronic endoscope without providing a special identification information transmitting terminal or the like. It is intended to provide a mirror device.

[0015]

In order to achieve the above object, an electronic endoscope apparatus according to the present invention connects an electronic endoscope having a solid-state image pickup device as an image pickup means to the electronic endoscope. The signal processing apparatus includes a method determining unit that determines the image capturing method of the electronic endoscope based on the magnitude of the carrier component of the output signal of the solid-state image sensor. There is.

[0016]

The signal processing device processes the output signal of the solid-state image pickup device, and at this time, the system discriminating means determines the output signal of the solid-state image pickup device according to the magnitude of the carrier component of the signal. The imaging method is determined.

[0017]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 10 relate to an embodiment of the present invention. FIG. 1 is a block diagram showing a main part of an electronic endoscope apparatus, FIG. 2 is a side view showing a configuration of the electronic endoscope apparatus, and FIG. 3 is a CCD. FIG. 4 is a block diagram showing the configuration of the discriminating means, FIG. 4 is a diagram showing signals referred to when measuring an image portion, FIG. 5 is a block diagram showing an example of a system discriminating circuit, and FIG. 6 is a (A) carrier detector. FIG. 7 is a block diagram showing another example of the system discriminating circuit, FIG. 8 is a block diagram showing a freeze circuit, and FIG.
FIG. 9 is a block diagram showing a motion detection circuit in the freeze circuit of FIG. 8, and FIG. 10 is a diagram showing the relationship between the magnitude of the detection amount and the memory update timing.

As shown in FIG. 2, the electronic endoscope apparatus 1 includes
Electronic endoscope 2, video processor 3 for processing an output signal from electronic endoscope 2, and video processor 3
A monitor 4 for displaying an image signal from the monitor 4 and a light source device 5 for supplying illumination light to the electronic endoscope 2 constitute a main part thereof.

The electronic endoscope 2 has a slender insertion portion 9 extending toward the front from a large-diameter operation portion 8 which also serves as a grip portion on the proximal side. This insertion part 9
Is the flexible tube portion 11, the bending portion 12,
A hard tip portion 13 is continuously provided. The operation section 8 includes
A bending operation knob 14 is provided, and by rotating the bending operation knob 14, the bending portion 12 can be bent in the left-right direction or the up-down direction. Further, the operation portion 8 has an insertion opening 15 that communicates with a treatment tool channel provided in the insertion portion 9. This operation unit 8
Has a flexible universal cord 16 extending from the side of the rear end thereof, and a connector 16 provided at the front end.
The light source device 5 is connected by a.
This connector 16a has a video cord 17 from its side.
Is extended and is connected to the video processor 3 by a connector 17a. This video processor 3
Incorporates various signal processing circuits, which will be described later, and processes the image pickup signal obtained from the endoscope 2 and displays it on the monitor 4 or the like.

Next, the configuration of the video processor 3 will be described along with the operation of the electronic endoscope apparatus 1 with reference to FIG.
Illumination light emitted from the light source device 5 is transmitted from the universal cord 16 to the endoscope distal end portion 13 through the light guide 21 provided in the insertion portion 9 of the endoscope 2, and the emission end face thereof causes an object to be photographed. It is emitted toward 22. The optical image of the subject illuminated by the illumination light is a CCD, which is a solid-state image sensor, by an objective optical system 24 provided inside the tip portion 13.
Imaged on 25. The CCD 25 is operated by a drive circuit 35 provided in the video processor 3, photoelectrically converts the formed subject image, and the image signal is CCD discriminating means 31 in the video processor 3. It is designed to be transmitted to.

The CCD discriminating means 31, as will be described in detail later, has a CCD which the connected endoscope 2 has.
25, for example, the type is determined based on the number of pixels, etc., and based on this determination signal, the processing of each drive circuit 35, pre-process circuit 32, freeze circuit 33, post-process circuit 34, etc., which will be described later, is controlled. It is supposed to do.

The output signal of the CCD discrimination means 31 is inputted to the preprocess circuit 32 and the system discrimination circuit 36, respectively. As will be described in detail later, the system discriminating circuit 36 discriminates whether the connected endoscope 2 is a frame sequential system or a simultaneous system, and the drive circuit 3 is determined by the discriminant result.
5, the processing of the pre-process circuit 32, the freeze circuit 33, the post-process circuit 34, etc. is controlled.

The preprocess circuit 32 performs gamma correction and AGC (auto gain control) processing,
Further, in the case of the simultaneous method, processing such as color separation is performed. The output of the pre-process circuit 32 is input to the freeze circuit 33, which performs synchronization and freeze control (preventing color misregistration) in the case of the frame sequential method, and image freeze (prevention of blurring) in the case of the simultaneous method. The output signal from the freeze circuit 33 is input to the post-process circuit 34 to be subjected to contour correction, color correction, encoding, etc., and then output to a device such as the monitor 4.

Next, the CCD discrimination means 31 is shown in FIG.
This will be described with reference to FIG. CC that power was turned on
When the D discrimination instruction means 31e detects, the pulse generator 31
A timing pulse is generated so that d can read a sufficiently large number of pixels, and the CCD driving circuit 35 drives the CCD 25. The image signal read from the CCD 25 is input to a CDS (correlated double sampling) 31a to remove reset noise, and then output as an image signal. This output image signal is branched into two, one of which is input to the preprocessing circuit 32 for image processing, and the other is input to the video portion counting means 31b.

In the image portion counting means 31b, as shown in FIG. 4, the number of pixels in the horizontal image portion is first counted from the output of the CDS 31a to obtain the horizontal image number, and the CCD
It is supplied to the determination circuit 31c. This CCD discrimination circuit 31c
Then, the type of the CCD 25 is discriminated from the obtained number of horizontal pixels, and the pulse generator 31d is instructed to generate a timing pulse suitable for the type. When it is not possible to determine which type the CCD 25 is based on the number of horizontal pixels, the CCD 25 is driven at the cycle of the number of horizontal pixels so that the number of pixels in the vertical image portion is the same as that in the horizontal image portion. Count and CCD discrimination circuit 31
In c, the type of the CCD 25 is discriminated from the number of horizontal pixels and the number of vertical pixels, and an instruction is issued to the pulse generator 31d to generate a timing pulse suitable for that type.

The image signal thus read out with the normal timing pulse is subjected to image processing by the timing pulse from the pulse generation and output as an image signal. Since the number of pixels is detected from the output of the CCD to discriminate the CCD type in this manner, it is not necessary to add a component such as a terminal for identifying the CCD, and the type of the CCD that can be discriminated is almost limited. It has the advantage of disappearing.

Next, the system discriminating circuit 36 will be described with reference to FIGS. The system discrimination circuit 36
As shown in an example of FIG. 5, is composed of, for example, a carrier detector 41 and a discriminator 42, and discriminates the imaging method of the endoscope during white balance control.

The white balance is controlled so that a white object is imaged by the endoscope 2 so that the color signal thereof becomes a predetermined level. In the white balance control, first, the control circuit 37 in the video processor 3 sets the frame sequential rotation filter (not shown) provided in the light source device 5 to red (R), and the red illumination is performed via the light guide 21. The light is directed toward the subject. At this time, since the subject is white as described above, the CCD 25 outputs a signal corresponding to red.

When the electronic endoscope 2 is of the simultaneous type, C
Since the CD 25 has a color separation filter on its image pickup surface, the signal corresponding to the red subject is a signal including a color carrier component as shown in FIG. 6 (A). By detecting this color carrier component by the carrier detector 41, a detection signal as shown in FIG. 6B can be obtained.

On the other hand, when the electronic endoscope 2 is a frame sequential type, since the CCD 25 is for monochrome, its output signal becomes a signal corresponding to a white object for white balance, and a high frequency component corresponding to a carrier component. Contains almost no. Therefore, this CCD output is used as the carrier detector 41.
When detected by, the output signal becomes almost zero.

The discriminator 42 discriminates the detection signal obtained from the carrier detector 41,
It is adapted to judge whether the endoscope 2 is a frame sequential type or a simultaneous type. At the time of this determination, as described above, the detection signal becomes a certain level when the electronic endoscope 2 is of the simultaneous type, and becomes almost zero when the electronic endoscope 2 is of the frame sequential type. If a value is set and the obtained detection signal is equal to or higher than the threshold value, it may be determined as a simultaneous expression, and if it is less than or equal to the threshold value, it may be determined as a frame sequential expression.

Based on the discrimination signal from the discriminator 42, the operations of the pre-process circuit 32, the freeze circuit 33, the post-process circuit 34, etc. are changed. Then, after performing the method determination and the operation change, the white balance operation suitable for the method is started.

Although the case where the red filter is inserted as the color filter has been described above, it goes without saying that the same operation can be performed even if a green (G) or blue (B) filter is inserted.

Next, another example of the above system discriminating circuit will be described with reference to FIG. The signal input to the system discriminating circuit 36 is input to the carrier detector 41 after a predetermined portion is extracted by the gate circuit 45. The averaging circuit 46 averages and holds a predetermined field of the output of the carrier detector 41. The size of the averaged carrier data is discriminated by the discriminator 42 to determine whether the endoscope 2 is a frame sequential type or a simultaneous type.

This judgment is made, for example, in the inside of the body, because the averaged carrier data in the simultaneous system becomes larger than that in the frame sequential system. That is, in the case of a medical endoscope, the color of the subject is mainly a reddish color. Therefore, if a sufficiently bright screen portion is detected and gated, the color will be increased when the electronic endoscope 2 is of the simultaneous type. Since carriers are generated, the detection averaged output becomes a signal having a certain value. On the other hand, when the electronic endoscope 2 is a frame sequential type, the solid-state image pickup device is monochrome and does not generate color carriers, so the averaged output of detection is close to zero. By discriminating the detected average value by the discriminator 42 with a certain threshold as a boundary, the imaging method of the electronic endoscope 2 can be determined. The operation of the pre-process circuit 32, the freeze circuit 33, and the post-process circuit 34 is changed using the output signal of the discriminator 42 as in the example shown in FIG.

The structure shown in FIG. 7 has substantially the same effect as that of the structure shown in FIG. 5, and has an advantage that the imaging method of the endoscope can be discriminated without depending on the white balance. .

Next, the operation of the freeze circuit 33 will be described with reference to FIG. CCD discrimination means 31
The output image signal of is divided into two and is input to the memory 51 and the motion detection circuit 53.

The motion detecting circuit 53 operates in accordance with the freeze control signal and is constructed as shown in FIG. That is, the input image signal is input to a high-pass filter (abbreviated as HPF in the figure) 55, and its high frequency component is extracted. This high frequency component is detected by the detection circuit 56, and a signal having a magnitude corresponding to the amount of the high frequency component is obtained. Here, the higher the image blur, the smaller the high-frequency component of the image signal. Therefore, it can be said that the larger the output of the detection circuit 56, the smaller the blur. When the freeze control signal is input, first, the detection signal of the first field is input to the maximum value store circuit 58, and the freeze signal is input to the memory control circuit 52 by the comparator 57.

The memory control circuit 52 controls the memory 51 so as to freeze the image signal in the field corresponding to the first detection signal. Then, when the image signal of the next field is input, the high pass filter 55 and the detection circuit 56 similarly detect a value corresponding to the motion amount, and the detected value and the maximum detection value stored in the maximum value storage circuit 58. Are compared by the comparator 57.

Here, when the stored maximum detection value is large, the image memory 51 is not updated and the stored maximum detection value is not updated. On the contrary, when the maximum detected value stored is small, the memory control circuit 52 is instructed to update the memory 51, and the detected value for the movement at that time is updated as the maximum detected value of the maximum value storing circuit 58. By operating in this way, an image with a large motion detection value after the freeze control signal is input,
That is, the one with the smallest movement is frozen while being updated one after another.

FIG. 10 shows the relationship between the magnitude of this detection amount and the timing at which the memory is updated. The memory is updated at the black circles in FIG.

If the operation as described above is finished within a predetermined period after the freeze control signal is input, it is possible to freeze the image with the least movement during the predetermined period.

In the example of the motion detection circuit 53 shown in FIG. 9, the high pass filter 55 is used to detect the blur, but a band pass filter may be used instead.
Further, a plurality of high-pass filters and band-pass filters may be used to switch or combine them depending on the screen and the magnitude of the motion.

Since the motion detecting circuit 53 as described above has a simple system, it can be realized by only an analog circuit, and the cost can be reduced and the circuit can be downsized.

According to the freeze circuit as shown in FIGS. 8 to 10, when the endoscope is a frame-sequential type, the image with the smallest color shift is obtained, and when the endoscope is the simultaneous type, the image with the smallest blurring is obtained. Each can be frozen.

According to such an embodiment, by discriminating the difference in the image pickup method such as the frame sequential type or the simultaneous type of the electronic endoscope by the difference in the carrier component of the CCD output, the special identification information transmission It is possible to provide an electronic endoscope device that does not need to be provided with a terminal or the like. Further, by providing the CCD discrimination means, the type can be discriminated from the number of pixels of the CCD included in the endoscope. Furthermore, by providing the freeze circuit, it is possible to obtain a still image with little color shift or blurring.

[0047]

As described above, according to the present invention, the electronic endoscope apparatus capable of discriminating the difference in the image pickup method of the electronic endoscope without providing a special identification information transmitting terminal or the like. Can be

[Brief description of drawings]

1 to 10 relate to an embodiment of the present invention,
FIG. 1 is a block diagram showing the main part of the electronic endoscope apparatus.

FIG. 2 is a side view showing the configuration of the electronic endoscope apparatus.

FIG. 3 is a block diagram showing the configuration of a CCD discriminating means.

FIG. 4 is a diagram showing signals to be referred to when measuring an image portion.

FIG. 5 is a block diagram showing an example of a system discrimination circuit.

FIG. 6A is a signal input to a carrier detector, and FIG.
The line diagram which shows each signal output from a carrier detector.

FIG. 7 is a block diagram showing another example of a system discrimination circuit.

FIG. 8 is a block diagram showing a freeze circuit.

9 is a block diagram showing a motion detection circuit in the freeze circuit of FIG.

FIG. 10 is a diagram showing the relationship between the amount of detection and the timing of memory update.

FIG. 11 is a block diagram showing an example of a conventional electronic endoscope apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Electronic endoscope apparatus 2 ... Electronic endoscope 3 ... Video processor 25 ... CCD 31 ... CCD discrimination means 33 ... Freeze circuit 36 ... System discrimination circuit

Claims (1)

[Claims] 1. An electronic endoscope apparatus comprising: an electronic endoscope including a solid-state image sensor as an image pickup means; and a signal processing device to which the electronic endoscope is connected, wherein the signal processing device is the solid-state image sensor. An electronic endoscope apparatus comprising: a system discriminating means for discriminating an image capturing system of the electronic endoscope according to a magnitude of a carrier component of an output signal of the image pickup device.