JPS63209626A - Electronic endoscope apparatus - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to an electronic endoscope device, and particularly to an isolation circuit for insulating a patient side circuit system and a secondary side circuit system. be.

[Conventional technology]

In recent years, an endoscopic arm has been proposed in which a solid-state image sensor is inserted into the tip and the @m signal is extracted as a photoelectrically converted electrical signal.

In the case of a medical electronic endoscope, the circuit section inserted into the patient's body (patient circuit) and the circuit section connected to peripheral devices such as a monitor (secondary circuit) are N! Must be given 3hR. FIG. 8 shows an exemplary configuration of a conventional electronic endoscope of this kind. In FIG. 8, a subject 1 is photoelectrically converted by an optical system 2, and the signal is sent to a video signal processing circuit 5 through a cable 4. Since the video signal processing circuit 5 is connected to peripheral devices such as a monitor, the video signal is
It is necessary to provide isolation between the patient circuit side and the secondary circuit side by means of an isolation four circuit 6 inside the video signal processing circuit 5.

Such isolation methods include a method in which the output of the solid-state image sensor is directly passed through an inlay transformer;
For example, in the case of COD, there is a method in which a signal obtained by delaying the original signal by half the pixel sampling period and a signal obtained by taking the difference between the original signal are passed through an isolation transformer to sample the effective signal portion.

Conventional electronic endoscopes as described above are disclosed, for example, in Japanese Patent Laid-Open Nos. 58-69528 and 1981-198161.

[Problem to be solved by the invention] When isolating the patient circuit and the secondary circuit, the output of the solid-state image sensor cannot be directly passed through the isolation system because the signal has a low frequency component. .

In the case of COD output, if the signal has a delay difference within it, it can pass through an isolation transformer, but there is a problem that reliable sampling cannot be performed because the high frequency components of the signal are attenuated when passing through the transformer.

ζIn this case, measures to reduce the noise of the output of the solid-state image sensor may be taken on the patient circuit side, but in this case, the signal band is only the baseband, so there is a drawback that it cannot be transmitted using an isolation transformer.

An object of the present invention is to provide an electronic endoscope apparatus in which noise reduction is performed on the output of a solid-state image sensor on the patient circuit side, and then isolation is performed.

[Means and effects for solving the problem] The electronic endoscopic arm device of the present invention reliably applies noise reduction measures such as correlated double sampling to the output of the solid-state image sensor on the patient circuit side, and then performs AM or AM. Adopts an isolation method that performs band conversion using FM modulation, isolates the patient circuit from the secondary circuit using isolation elements such as transformers and photocazola, and demodulates the secondary circuit to generate the original signal. It is characterized by:

〔Example〕

The present invention will be described in detail below with reference to the drawings.

First Embodiment First, an electronic endoscopic G8 apparatus according to a first embodiment of the present invention will be described with reference to FIG.

Here, the solid-state image sensor 3 includes a COD (charge-coupled device), an MO8 type solid-state image sensor, and the like.

In FIG. 1, an image of a subject 1 is received by a solid-state image pickup device 3 via an optical system 2 and extracted as a video signal. A video signal output from the solid-state image sensor 3 is sent to a video signal processing circuit 5 through a cable 4.

The video signal is first subjected to noise reduction measures such as correlated spectral sampling in a noise reduction circuit 1, and then passed through a low-pass filter 8 to extract only the pace noise component of the video signal. Next, the modulation circuit 9 outputs 5, AM or F.
MK tone. This modulation signal is transmitted to isolation element 1.
0 from the patient circuit to the secondary circuit. As the isolation element 10, a high frequency transformer is used when AM modulation is performed, and a high frequency transformer, high frequency 7 otokapu 2, etc. is used when FM modulation is performed. The isolated signal is demodulated into an original signal by a demodulation circuit 11 and then sent to a main processing circuit 12 for predetermined signal processing.

In this way, the feature of ensuring signal isolation between the patient circuit system and the secondary circuit system can be seen.

Second Embodiment Next, a second embodiment of an electronic endoscope using a line-sequential color CCD is shown in FIG. Note that circuits that are the same as those in FIG. 1 are given the same numbers. Here, the baseband only component of the output signal from which unnecessary components have been removed through the low-pass filter 8 is a chrominance carrier wave added to the N-degree signal as shown in the MaA diagram. This signal is separated into a luminance signal (FIG. 3B) and a color carrier wave (FIG. 3C) by a low-pass filter 13 and a pantone filter 14. This luminance signal is transmitted to the modulation circuit 9 as in the first embodiment.
The signal is modulated by the patient and sent from the patient circuit to the secondary circuit through the isolation element 10.

Similarly, the demodulation circuit 11 outputs the brightness signal that is lost due to isolation.
The demodulated signal is sent to the main processing circuit 12. - Since the multicolored carrier wave signal is a balanced modulation of the color difference signal, it is input to the isolation 1 element 15 and sent from the patient circuit to the secondary circuit. In this case, a high frequency transformer is used as the aluminum element. The color carrier wave No. 46 that has been decoded from the inlay is demodulated by the demodulation circuit 16 and is then demodulated by the main processing circuit 1.
2, and is subjected to signal processing together with the luminance signal.

Third Embodiment Next, as a third embodiment, an electronic endoscope apparatus using a color COD in which color information is obtained by sampling is shown in FIG. The COD J output passes through a noise reduction circuit 7 and is separated into each color signal by a sampling circuit 17. Here, if the color filter arrangement of the CCD 3 is a Bayer arrangement and R and B information can be obtained for each row, the signal is a signal that is to be serialized as G (No. 5).Here, G
The signal is modulated by the modulation circuit 9 as in the first embodiment and sent from the patient circuit to the secondary circuit through the isolation element 10. On the other hand, the j-order signal is similarly modulated by the modulation circuit 18 and sent from the patient circuit to the secondary circuit through the isolation 1 element 15. G in the secondary circuit
The signal and the Rβ signal are demodulated by demodulation circuit 11 and demodulation circuit 16, respectively, and sent to main processing circuit 12 where they are similarly processed.

Fourth Embodiment Generally, the band of color difference signals obtained from a solid-state image sensor that is colored by one filter array is f = 0.5.
It is about MHz. Therefore, as shown in FIG. 6A, it is sufficient to maintain the same color difference signal for 2H periods in the vertical direction. Therefore, FIG. 5 shows a fourth embodiment of an electronic endoscope system in which color difference signals are serialized and subjected to isolation vibration. The output of the solid-state image sensor 3 is sent to a video signal processing circuit 5 through a cable 4. The video signal is finally processed by a preprocessing circuit 19 into a luminance signal Y and a color difference signal RY.

B-Y is obtained. Here, the color difference signals R-Y, B-Y
becomes a sequential signal in the condylarization circuit 20 as shown in FIG. 6B. After that, the luminance signal and the color difference signal are modulated by the modulation circuit 8 and the modulation circuit 18, respectively, as in the third embodiment, and the isolage element 10 and the isolage 1
The signal is sent from the patient circuit to the secondary circuit through the control element 15.

The luminance signal is demodulated by the demodulation circuit 11 and sent to the main processing circuit 12.

On the other hand, the color difference signal is demodulated by a demodulation circuit 16, synchronized by a synchronization circuit 21, and sent to the main processing circuit 12, where it is processed together with the luminance signal.

Here, isolation is possible without sequentializing the color difference signals, but in that case, the number of modulation circuits, demodulation circuits, and isolation elements will be increased by one each.

Fifth Embodiment Finally, as a fifth embodiment, there is a method of performing orthogonal transformation isolation of color difference signals. Two block diagrams of this system are shown in FIG. The output of the solid-state image sensor 3 is sent to a video signal processing circuit 5 through a cable 4. The video signal is converted into a final luminance signal and quadrature modulated chroma signal in the patient side signal processing circuit 22. The luminance signal is the first
As in the embodiment, the signal is modulated by the modulation circuit 9 and sent to the secondary circuit side through the isolation element 10. nine "
The ROMA signal is sent as it is to the secondary circuit side through the isolation quadruple element 15. The luminance signal is demodulated in a demodulation circuit 11, and combined with the synchronization signal and the chroma signal in an NTSC output circuit 23 to produce an NTSC output.

〔Effect of the invention〕

As described in detail above, according to the present invention, it is possible to reliably perform noise reduction processing on the patient circuit side, and furthermore, there is an effect that insulation between the patient circuit side and the secondary circuit side can be sufficiently performed.

[Brief explanation of the drawing]

i; g1 is a block diagram showing the arrangement of the first embodiment of the present invention; FIGS. 2 and 3A to 3C are block diagrams showing the arrangement of the second embodiment; Figures 4 to 7 are block diagrams showing the configurations of the same third to fifth embodiments, and signal waveform diagrams for each part. Figure 8 is a diagram of conventional electronic endoscopy. FIG. 2 is a block diagram showing the configuration of a mirror device. 1... Subject, 3... Solid-state imaging confectionery, 5... Video signal processing circuit, 7... Noise reduction circuit, 10.15.
... Isolation element, 12 ... Main processing circuit, 1
9... ifJ processing circuit, 20... sequentialization circuit. Applicant's representative Patent attorney Atsushi Tsuboi C.Fuge procedural amendment 1999-3/2015 Director General of the Patent Office Kunio Ogawa 1, Indication of case Patent application No. 1982-43578 2, Title of invention electronic Relationship between endoscopic m device 3 and correction incident Patent applicant (037) Olympus Optical Industry Co., Ltd. 4 Agent Uo Building 3-7-12 Kasumigaseki, Chiyoda-ku, Tokyo 10
0 Telephone 03 (502) 3181 (main representative) 6
6. Subject of amendment 1 store 7. Contents of amendment

Claims (1)

[Claims] 1) A solid-state imaging device that converts optical information into a video signal;
In an electronic endoscope apparatus in which this imaging device is disposed at the distal end and this device and a camera controller are electrically connected by a cable member, a patient circuit system including the solid-state imaging device receives images from the imaging device. An electronic device comprising: a modulating means for modulating a signal; and an isolation means for performing isolation processing and transmitting a modulated video signal from the modulating means to a secondary circuit system including the camera controller. Endoscope equipment. 2) The electronic endoscope apparatus according to claim 1, further comprising a noise reduction means provided before the modulation means. 3) The electronic endoscope apparatus according to claim 1, wherein an AM modulator or an FM modulator is used as the modulation means. 4) The electronic endoscope apparatus according to claim 1, wherein a high frequency transformer or a photocoupler is used as the isolation means.