JPS6254215A - Electronic type endoscope device - Google Patents

Abstract

PURPOSE:To prevent the necessity that the matching of the endoscope and the processing part is manually executed each time the type of the endoscope is changed by providing the video processor having the circuit to process the signal concerning the solid image pick-up element constituted freely detachably at the endoscope. CONSTITUTION:The driving clock is supplied from a driving clock circuit 21 to a signal line 22 of an endoscope 11 of the long type, and when a CCD 13 is driven, the image signal to occur at the CCD 13 is delayed only for the delaying time of a delaying line 18 and supplied to a video signal processing circuit 20. When an endoscope 25 of the short type is connected to a video processor unit 19, the image signal arrives at a delaying line 27 through a transmitting line 28 faster than the endoscope 11 of the long type, the delaying line 27 has the delaying time longer than the delaying line 18 from the delaying line 18, and the image signal obtained from a CCD 29 of the endoscope 25 is supplied to the video signal processing circuit 20 by the same phase as the image signal to pass through the delaying line 18.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an endoscope, and particularly to an electronic endoscope device incorporating a solid-state imaging probe.

[Prior Art J] In an electronic endoscopic device, drive pulses are supplied from an external video processing device to a solid-state image sensor provided at the tip of the endoscope, and the solid-state image sensor is driven by the drive pulses. An image signal is generated from the solid-state image sensor. In this case, the driving pulse is supplied to the solid-state image sensor via the signal cable provided in the endoscope insertion part, but this signal cable has an actance, so when the driving pulse is transmitted through the signal cable, the effect of the actance is affected. received (
Distortion occurs in the initial pulse. In order to prevent this distortion, a conventional video processing apparatus is provided with a waveform compensation circuit, and the drive pulse is configured to be compensated for the distortion.

[Problems to be Solved by the Invention] Distortion can be prevented by a waveform compensation circuit, but if the length of the endoscope changes depending on the type of endoscope, the length of the signal cable will change accordingly, and the signal cable actance will change. Change. Therefore, the characteristics of the waveform compensation circuit must be changed every time the type of endoscope, that is, the length of the endoscope changes. Conventionally, an adjuster such as a variable resistor is provided to change the characteristics of the waveform compensation circuit, and this adjuster is operated to match the waveform compensation circuit and the signal cable of the endoscope. This conventional method has the problem that the characteristics of the waveform compensation circuit must be changed for each type of endoscope, making the operation of the endoscope extremely troublesome. This invention was made in view of these problems, and provides an electronic endoscope device that does not require manual alignment between the endoscope and the processing unit each time the type of endoscope is changed. The purpose is to provide and cover the following.

[Means for Solving the Problems] According to the present invention, there is provided an endoscope having a distal end portion incorporating a solid-state image sensor that is driven by a drive pulse and outputs an optical image as a video signal; An electronic system comprising: a video processor configured to allow film deposition, and having a circuit for processing signals related to the solid-state image sensor; and matching means for matching the circuit of the video processor with a signal system related to the solid-state image sensor. A viewing device is provided.

[Operation] According to this device, an electronic endoscope of type W can be used in compatible combination with a video processor of type -.

Embodiment] FIG. 1 shows a schematic configuration of an electronic endoscope apparatus according to an embodiment of the present invention. When this happens, a solid-state imaging device (COD) is installed at the distal end 12 of the endoscope 11, which has a long insertion section.
13 is provided, and the video signal output end of this CCD 13 is connected to one end of a transmission line 16 provided via an endoscope insertion portion 14 and a universal cord 15. The other end of the transmission line 16 is connected to one end of a delay line (delay element) 18 provided on an endoscope connector 17.

The other end of delay line 18 is connected to the input of video signal processing circuit 20 of video processor unit 19 via a pin (not shown) of connector 17.

The output of the drive clock circuit 21 provided in the video processor units 1 to 19 is connected from the connector 17 to the signal line 22 connected to the drive signal input end of the CCD 13 via the universal cord 15 and the endoscope insertion section 14. . Video signal processing circuit 20 is connected to monitor TV 23. An endoscope 1t25 with a short insertion section can be connected to this video processor unit 19. In this case, a delay line 27 provided on the connector 26 of the endoscope 25
has a longer delay time than delay line 18. That is, the delay times of both delay lines 18 and 27 are set so as to eliminate the phase difference between the video signals due to the delay caused by the transmission line 16 and the delay caused by the transmission line 28. Although not shown in the figure, illumination light is introduced into the lines 1 to guides 24 of the endoscopes 11 and 25.

In the above embodiment, when a drive clock (Fig. 2) is supplied from the drive clock circuit 21 to the signal line 22 of the long type endoscope 11 and the CCD 13 is driven, the CG
The video signal generated at D 13 is supplied to a delay line 18 via a transmission line 16. In this case, the video signal is input to the delay line 18 with some delay from the drive clock depending on the length of the transmission line 16. The video signal number is the delay time of the delay line 18 [J is delayed and supplied to the video signal processing circuit 20.

The video signal is processed by the video signal processing circuit 20, supplied to the monitor TV 23, and displayed as a video on the monitor TV 23.

Next, when the short type endoscope 25 is connected to the video processor unit 1-19, the video signal is transmitted through the transmission line 28 more quickly than in the case of the long type endoscope 11, as shown in FIG. Delay line 27 is reached. Since this delay line 27 has a longer delay time than the delay line 18, the video signal obtained from the C0D 29 of the endoscope 25 is supplied to the video signal processing circuit 20 in the same phase as the video signal that has passed through the delay line 18. Ru. Therefore, the video signal processing circuit 20 can perform signal processing in synchronization with a constant drive clock, since the input video signals have the same phase relationship regardless of the length or length of the endoscope.

According to the embodiment of FIG. 3, the connector 32 of the endoscope 31 is provided with trimmers 33, 34, 35, 36. These limas 33 to 36 are connected in parallel and connected to a constant voltage circuit 39 of a video processor unit 37.

Transmission line 40 is connected to the input of sample and hold circuit 41. The output of the sample hold circuit 41 is connected to a gamma correction circuit 44 via an amplifier circuit 42 and an AGC circuit 43. The output of the gamma correction circuit 44 is connected to a color processing circuit 45, and the output of this color processing circuit 45 is connected to the monitor TV 23.

The Luray clock circuit 46 is connected to the signal line 47, and the sample bold circuit 41 and the gamma correction circuit 44.
and the color processing circuit 45 so as to provide sampling pulses, clamp pulses, and synchronization signals, respectively, to these circuits. The trimmers 1 to 33 and 34 are connected to the AGC circuit 43 and the gamma correction circuit 44, and the trimmers 35 and 36 are connected to the AGC circuit 43 and the gamma correction circuit 44.
is connected to the color processing circuit 45.

According to the embodiment shown in FIG. 3 above, l-lima 33 to 3
6, the reference voltages F1, E2, E3, and E4 are set. That is, the trimmer 33 adjusts the reference voltage F1 of the AGC circuit 43 so that the AGC state is optimal for the brightness of the optical system of the endoscope.
Set. Furthermore, this AGC setting also absorbs variations in sensitivity of the solid-state imaging probe provided in the endoscope.

The trimmer 34 is adjusted to obtain gamma characteristics depending on the use of the electronic endoscope 31. The trimmers 35 and 36 are adjusted to obtain a white balance according to the optical characteristics of the light guide of the endoscope 31.

As mentioned above, for each type of endoscope, the trimmers 33 to 36 are preset according to the characteristics of each endoscope, so that the video processor unit 37 is provided with the trimmer. Even when an endoscope is connected, the video signal processed by the video processor unit 37 is displayed on the monitor TV 23 as an optimal image.

The operation of the electronic endoscope device shown in FIG. 3 will be explained.

A drive clock is supplied from the drive clock circuit 46 to the distal end of the endoscope 31 via the drive clock signal line 47. is input.

The sample and hold circuit 41 samples and holds the video signal in synchronization with the sampling pulse from the drive clock circuit 46. The video signal from the sample and hold circuit 41 is amplified by an amplifier circuit 42 and input to an AGC circuit 43. The GC circuit 43 inputs a gain control signal corresponding to the gain set according to the type of the inner pA mirror 31 to the amplifier circuit 42, and controls the gain of the amplifier circuit 42. Thereby, the video signal is processed into a signal according to the sensitivity of the optical system of the endoscope 31 and the image carrier element. AGC
When the video signal via the circuit 43 is input to the gamma correction circuit 44, the video signal is subjected to gamma correction in synchronization with the clamp pulse from the drive clock circuit 46 according to the setting value of the trimmer 34. The video signal is processed by gamma correction so that color reproducibility suitable for the use of the endoscope is obtained. When the gamma-corrected video signal is input to the color processing amount 845, it is processed so that the white balance set by Lima 35 and 36, that is, the white balance according to the optical characteristics of the endoscope light guide, is obtained. The video signal is subjected to signal processing.

Next, the embodiment shown in FIG. 4 will be explained. According to this embodiment, a video processor unit 52 to which an endoscope connector 51 is connected is provided with a video signal processing circuit 54 connected to a video signal transmission line 53 and a drive circuit 56 connected to a drive signal line 55. Furthermore, drive clock generation circuits 58 and 59 are provided, which are responsible for the frequency and number of pulses. The outputs of drive clock generation circuits M58 and M59 are connected to a switching circuit 57. This switching circuit 57 selects one of the drive clock generation circuits 58 and 59 in response to a switching signal, for example, a level or 0 level signal, depending on the jumper connection state of the pin 60 connected to the endoscope connector 51. . The jumper M connection state of the pin 60 of the connector 51 is determined by the number of pixels of the solid-state imaging device of the endoscope 50. For example, when an endoscope using a solid-state imaging device with the number of pixels of N is connected to the video processor unit 52. Then, the drive clock of the drive clock generation circuit 58 is transmitted to the drive circuit 56 and the video signal processing circuit j! 854, the switching circuit 57 is activated. When an endoscope using a solid-state B image element with M pixels (M>N>) is connected, the drive clock of the drive clock generation circuit 59 is guided to the drive circuit 56 and the video signal processing circuit 54. The switching circuit fa57 is activated.The clock signals of the drive clock generation circuits 58 and 59 are input to the video processing circuit 54 as synchronization signals, clamp pulses, and sampling pulses, and are also input to the drive circuit 56 as element drive clock pulses.

In the actual mgAJ shown in FIG.
, the drive circuit 56 sends a drive signal with a frequency and a pulse number corresponding to the number of pixels N to the endoscope 5 via the signal line 55.
0 solid-state image sensor. The solid-state image sensor is driven in synchronization with the frequency and pulse number of the drive signal and outputs a video signal. The video signal is input to a video signal processing circuit 54 via a transmission line 53, subjected to signal processing, and input to a monitor TV.

When an endoscope having M pixels is connected to the video processor unit 52, N solid-state image elements are driven by the drive clock from the drive clock generation circuit 59 according to its frequency and pulse number.

When the electronic endoscope device of the above embodiment is used, the video processor unit 52 can be commonly used for electronic endoscopes using solid-state R image probes having different numbers of pixels without requiring any adjustment. .

Next, another embodiment will be described with reference to FIG.

The electronic endoscope device includes an electronic endoscope 111 and a video processor 112. An objective lens 113 and an illumination lens 114 are attached to the distal end portion 111a of the electronic endoscope 111. A device (COD) 115 is disposed on the solid-state camera facing the objective lens 113. The endoscope connector 111b configured to allow tG to the video processor 112 includes a delay circuit (Delay circuit).
Line) 116 and 117 and these delay circuits 1
First drivers 118 and 119 are provided which are connected to drivers 16 and 111, respectively. 1st driver 118 and 1
19 are connected to receivers 120 and 122, respectively, via coaxial cables of the endoscope insertion section 111C. Receiver 1
20 and 122 are connected to the CCD 115 via second drivers 21 and 23, respectively. A video signal output terminal of the CCD 115 is connected to a video signal processing circuit 129 of the video processor 112 via an emitter follower amplifier 133 and a coaxial cable.

It is made into a plug-in module separate from the endoscope 111 and configured to be detachably attached to the video processor 112. The drive circuit unit 124 includes the drive pulse generation circuit 12
5 and a first clock generation circuit 126 are provided.

The drive pulse generation circuit 126 inputs the clock signal fc1 to the drive pulse generation circuit 125, and the drive pulse generation circuit 126 inputs the clock signal fc1 to the drive pulse generation circuit 125.
25 is the signal PV1.25 from the clock signal fcl. PV2.
SH, CIP, NO, VD Sound formation. The drive pulse generation circuit 125 is configured to generate a clock signal fc1 having a frequency that is an integral multiple of the frequency of the drive pulse φR1φH.

Communication @ (PVI, PV2) output terminal pigeon driver 128
．． 127 respectively to the endoscope] connector socket] and (not shown). The signal (Pν1. PV2) output terminal is connected to the CCD 1 via the coaxial cable of the endoscope 111.
15. The signal (PR, P) output terminals are connected to the delay circuits 116 and 117 connected to the endoscope connector 111b, respectively. The signal (SH, CLP) output terminals are connected to the video signal processing circuit 129. (I
ID.

VD) output terminal is connected to the synchronization signal generation circuit 30.

This synchronization signal generation circuit 130 is a second clock generation circuit 1
Composite synchronization signal 5 is received in response to the second clock signal fc2 of 31.
Video signal processing circuit 1 for YNC and blanking signals
29.

In the electronic endoscope device having the above configuration, when the first tark generator 126 of the drive pulse generation circuit unit l-124 supplies the first clock signal fc1 to the drive pulse generator N125, the drive pulse generator M125 outputs the first clock signal fc1. Drive pulses PR and PH shown in FIG. 6 are supplied to delay circuits 116 and 111 provided in the endoscope connector 111b. The drive pulses PR and PH are delayed by a predetermined time t2 by delay circuits 116 and 117, and then sent to drivers 118 and 119.
is input. Drivers 118 and 119 perform impedance matching with the coaxial cable to generate drive pulses φR.
- and φH'.

The drive pulses φR- and φ1'' through the coaxial cable are input to receivers 120 and 122, respectively, provided at the distal end portion 111a of the endoscope.

Since the receivers 120 and 122 have characteristics that match the characteristic impedance of the circumferential cable, the driving pulses φR- and φH-
You can receive it. The output pulses of receivers 120 and 122 are transmitted to the CCD by drivers 121 and 123.
The signal is amplified to a voltage level necessary for driving the CCD 115, and is input to the CCD iis as high-speed drive pulse signals φR and φH. The drive pulse signal φ[ is used to operate the image signal output section of the tCCD 115, and the drive pulse signal φH is used for horizontal transfer of pixel signals. Also, CCD
IIS has a drive pulse! [From time N125, low-speed drive pulses φv1 and φν2 for vertical transfer are supplied.

The drive pulse signals φR and φH are high-frequency pulse signals of 7 MHz or higher, and when such high-frequency pulse signals are transmitted through normal electric wires, electromagnetic waves are emitted from the wires and cause interference to other equipment. However, when the drive pulse signal is transmitted through a coaxial cable with impedance matching as in this embodiment, there is no radiation of electromagnetic waves, and moreover, it is possible to transmit the drive pulse signal without causing distortion in the waveform. .

The CCD 115 is driven by drive pulse signals φR and φt1.
When driven, the CCD 115 outputs a video signal @VO in synchronization with drive pulse signals φR and φH.

ll! The II image signal VO is supplied to the video signal processing circuit 129 of the video processor 112 via a coaxial cable.

In the above operation, a time t2 is required from when the drive pulse signals φR" and φH- are output from the drivers 118 and 119 until the drive pulse signals φR and φH are supplied to the CCD 115. This time t2G is equal to the length of the coaxial cable. In addition, the image of CCD 115 @@VO
It still takes time t2 for the signal to reach the video signal processing circuit 129. When the video signal V<0> inputted to the video signal processing circuit 129 is subjected to signal processing in the video signal processing circuit 129, it is sampled by the sample-hold pulse signal SH output from the drive pulse generation circuit 125. Through this sampling, only the signal component in the middle of the video signal V〇- is acquired, and reset noise components and the like are removed.

The pulses of the signals 811, PR, and PH are always outputted to the drive pulse generation circuit 124 with the same phase relationship.

However, if the endoscopes have different lengths, that is, if the coaxial cables have different lengths, the time t1 will be different. Therefore, the phase relationship between the video signal vO° input to the video signal processing circuit 129 and the sampling pulse signal S11 shifts, and the video signal vO′ is not properly sampled. Therefore, delay circuits 116 and 117
The signal PH1PR is delayed by a time t2 in advance,
The delay circuits 116 and 1 are connected so that t2+2t1 is constant.
17 delays are determined.

Further, the drive pulse generation circuit 124 is configured so that the relationship between the video signal vO° and the sampling pulse signal SH is always appropriate.

The synchronization signal generation circuit 130 outputs a composite synchronization signal 5YNC and a blanking signal B[ by receiving the signal @110 and VD output from the drive pulse generation circuit 125. Note that the signals 110 and VD have horizontal and vertical frequencies that are determined by the television system (NTSC, PAI, etc.), regardless of the number of pixels of the CCD 115. Further, a reference clock pulse is required to obtain the signals 5YNC and OLD-, and the second clock signal fc2 is used as this reference lock pulse. The frequency of this second clock signal fc2 is set regardless of the number of pixels of the CCD 115. However, the drive signal PR1PH, sample hold pulse signal SH and clamp pulse C
I-P is determined according to the characteristics of CGD 115.

The video signal processing circuit 129 receives signals 8N, C1, P, 5
By receiving YNC and BLK, it processes the video signal @vO° and supplies it to the monitor television 32.

In the above embodiment, the matching circuit, such as a delay means, provided for matching the signal system of the video processor and the solid-state image sensor is not limited to being provided in the endoscope connector; It may be provided within the endoscope, such as the mirror operation section and the insertion section.

[Effects of the Invention] According to the present invention, various endoscopes with different endoscope characteristics such as the length of the transmission line provided in the endoscope, the number of pixels of the solid-state image sensor, or the optical characteristics of the endoscope can be used. Since the video processor unit can be commonly used for one type of endoscope without requiring adjustment for each type of endoscope, economy and operability are improved.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing a schematic configuration of an electronic endoscope device according to an embodiment of the present invention, FIG. 2 is a time chart diagram for explaining the operation of the endoscope device shown in FIG. 1, and FIG. 3 is a block circuit diagram of an endoscope apparatus according to another embodiment, FIG. 4 is a block circuit diagram of an endoscope apparatus according to another embodiment, and FIG. 5 is a block circuit diagram of an endoscope apparatus according to another embodiment. A block circuit diagram of the electronic endoscope apparatus according to the present invention is shown, and FIG. 6 is a time chart of signals for explaining the operation of the electronic endoscope apparatus of FIG. 11... Endoscope, 13... Solid-state image sensor, 16...
・Transmission line, 17... Endoscope connector, 18...
Delay line, 19... video processing unit,
20... Video signal processing circuit, 21... Drive clock circuit, 22... Drive signal line, 23... Monitor TV, 24... Light guide, 25... Endoscope, 2
6... Endoscope connector, 27... Delay line,
28...Transmission line, 32...Endoscope connector, 3
3 to 36... Trimmer, 37... Video processor unit, 51... Endoscope connector, 60... Pin,
111...Inner'pA mirror, 112...Video processor, 115...Solid-state imaging probe, 116.117...
Delay circuit, 118.119...driver, 120.1
22...Receiver, 121.123...Driver,
124... Drive pulse generation circuit unit, 125...
- Drive pulse generation circuit, 127.128... Driver, 129... Video signal processing circuit, 130... Synchronization signal generation circuit, 132... Monitor.

Claims (6)

[Claims] (1) An endoscope that has a distal end that incorporates a solid-state image sensor that is driven by drive pulses and outputs an optical image as a video signal; An electronic endoscope apparatus comprising: a video processor having a processing circuit; and matching means for matching the processing circuit of the video processor with a signal system related to the solid-state image sensor. (2) The electronic endoscope apparatus according to claim 1, wherein the matching means includes a transmission means for transmitting the drive pulse, and a delay circuit for delaying the drive pulse for a predetermined period of time. (3) The matching means includes a coaxial cable that transmits the drive pulse from the video processor to the solid-state image sensor, the delay circuit that is connected to the coaxial cable and delays the drive pulse for a predetermined time, and the endoscope. Claims comprising: a drive circuit provided at the tip of the drive circuit for driving the solid-state imaging device according to the drive pulse; and a matching circuit for matching impedances between the circumferential cable, the delay circuit, and the drive circuit. The electronic endoscope device according to item 1. (4) The electronic endoscope apparatus according to claim 1, wherein the matching means is provided in the signal system of the video signal and includes a signal delay circuit means specific to the type of the endoscope. (5) The electronic endoscope apparatus according to claim 1, wherein the matching means includes means for adjusting a correction system of the processing circuit of the video processor according to the unique characteristics of the endoscope. . (6) The electronic endoscope apparatus according to claim 1, wherein the matching means includes means for changing the output of the drive system of the processing circuit in accordance with the inherent characteristics of the endoscope.