JPH0431475B2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a remote drive type camera that separates a solid-state image sensor and a camera control unit that drives the solid-state image sensor and reads and processes image signals captured by the solid-state image sensor. Related to solid-state imaging devices.

[Technical background of the invention and its problems] The solid-state image sensor and the camera control section are separated, and the driving and
When signal processing is performed, it is performed using a circuit configuration as shown in FIG. 2, for example. That is, the remotely driven solid-state imaging device includes a head section 13 consisting of an optical system lens 11 and a solid-state imaging device 12, a synchronization and drive signal generation circuit 14 for driving the solid-state imaging device 12, a phase correction circuit 15, and a sample hold circuit. The head section 13 and the camera control section 18 are connected via a multi-core cable 19.

The remotely driven solid-state imaging device configured in this manner remotely drives and scans the solid-state imaging device 12 having a two-dimensional pixel array using various drive signals, and reads out time-series image signals. There is. That is, the readout transfer signal t ₁ from the synchronization and drive signal generation circuit 14 is output to the solid-state image sensor 12 via the buffer circuits 20 and 21, and the solid-state image sensor 12 receives this readout transfer signal t ₁ . A signal charge proportional to the amount of light received and irradiated from the optical system lens 11 is outputted to the sample hold circuit 16 via buffer circuits 22 and 23 as an image signal _t2 . Here, the signal t ₁ from the synchronization and drive signal generation circuit 14 is phase-corrected via the phase correction circuit 15 and input as a signal t ₃ to the sample hold circuit 16, and the image signal t ₂ is input to the sample hold circuit 16. Signal processing is performed based on this phase-corrected signal _t3 . That is, the sample and hold circuit 16 separates and extracts a portion of the image signal t ₂ corresponding to each image of the solid-state image pickup device, and performs signal processing.

FIG. 3 is a diagram for explaining the above-mentioned signal processing, and _FIG . image signal
The waveform diagram of t ₂ and figure c are the signals t ₃ obtained by φ phase correction of the readout transfer signal t ₁ by the phase correction circuit 15.
Figure d is a waveform diagram obtained by sample-holding the image signal _t2 based on the signal _t3 . That is, the image signal t ₂ outputted by the readout transfer signal t ₁ shown in figure a is output with a delay of phase difference φ and noise with respect to the readout transfer signal t ₁ as shown in figure b. It will be done. This is based on the input/output characteristics of the solid-state image sensor 12 and the multi-core cable 19.
Therefore, in order to remove noise from the image signal _t2 and perform effective signal processing, the readout transfer signal _t1 from the synchronization and drive signal generation circuit 14 is is converted into a signal t ₃ delayed by the phase difference φ via the phase correction circuit 15 and input to the sample hold circuit 16 . In the sample hold circuit 16,
The input signal _t3 is waveform-shaped in comparison with a certain reference level V _REF , and the input signal from the solid-state image sensor, that is, the image signal _t2 , is used to extract the effective component of the waveform-shaped signal, It is output to the process circuit 17 as a signal _t4 as shown in FIG.
The input signal _t4 is converted into a standard television system signal by the process circuit 17 and output.

In the remote-driven solid-state imaging device configured as described above, the head section 13 and the camera control section 18
A phase difference occurs between the readout transfer signal t ₁ and the image signal t ₂ depending on the length of the multi-core cable 19 connecting the , so in order to perform accurate signal processing,
The phase correction circuit 15 must be provided, which requires an increase in the number of circuits and the effort of adjustment. Further, individual adjustments may be required due to changes in the environment on the head section 13 side or camera control section 18 side, or changes in the length of the multi-core cable 19.

[Purpose of the Invention] The present invention has been made in view of the above points, and is a remote control system that enables accurate signal processing without being affected by external influences that occur when a solid-state image sensor is remotely driven. The purpose of the present invention is to provide a driven solid-state imaging device.

[Summary of the Invention] In other words, the remotely driven solid-state imaging device according to the present invention includes a head section comprising an optical system and a solid-state imaging device, a synchronization and drive signal generation circuit for driving the solid-state imaging device, and an image pickup device. A control section consisting of a signal processing circuit for processing the image signal generated by the sensor, and a multi-core cable for remotely connecting the head section and the control circuit, and a reference signal from the synchronization and drive signal generation circuit are connected to the sensor. The image sensor output signal is sent back to the signal processing circuit together with the image output signal, and the image sensor output signal is processed based on the sent back reference signal.

[Embodiment of the Invention] An embodiment of the invention will be described below with reference to the drawings. FIG. 1 is a circuit diagram of an embodiment of a remotely driven solid-state imaging device according to the present invention. The head unit 30 that captures the subject is composed of an optical lens 31 and a solid-state image sensor 32 that converts the subject image formed by the optical lens 31 into an electrical signal and accumulates it as a signal charge. Above head part 3
The object image captured by the camera 0 is sent to the camera control unit 34 via the multi-core cable 33. The camera control unit 34 includes a synchronization and drive signal generation circuit 35 for driving the solid-state image sensor 32.
, a sample hold circuit 36 for processing the output signal from the solid-state image sensor 32, and a processing circuit 37 for converting the signal obtained from the sample hold circuit 36 into a standard television signal.

The remote-driven solid-state imaging device configured in this manner uses a readout transfer signal T ₁ outputted from the synchronization and drive signal generation circuit 34 in the camera control unit 34 to read the solid-state imaging device 32 having a two-dimensional pixel array.
This is a remote-driven scanning system. That is, the readout transfer signal _T1 output from the synchronization and drive signal generation circuit 35 includes various synchronization signals for establishing synchronization between transmissions and a drive signal for driving the solid-state image sensor 32, and The transfer signal _T1 is passed through the buffer circuit 38,
The signal is output to the head section 30. The read transfer signal T ₁ is input to the solid-state image sensor 32 via the buffer circuit 39 of the head section 30 . The solid-state image sensor 32 receives the readout transfer signal T ₁ and outputs a signal charge proportional to the amount of light emitted from the optical system lens 31 to the buffer circuit 40 as an image signal T ₂ . The buffer circuit 40 converts the output from the solid-state image sensor 32 into a buffer circuit 4.
1 to the sample hold circuit 36.

Here, among the plurality of signals of the readout transfer signal _T1 , the signal _T3 used for finally reading out the image signal _T2 from the solid-state image sensor 32 is combined with the image signal _T2 to the camera control unit. 34. That is, the signals T ₂ and T ₃ are respectively transmitted to the camera control unit 3.
The signal is input to the sample hold circuit 36 through the buffer circuits 41 and 42 of
The image signal T ₃ is waveform-shaped by a certain reference level, and the image signal T ₂ is the waveform-shaped signal T _{3 .}
Processed based on. That is, the above signal T ₃
is a signal used to read out the image signal T ₂ , and is guided to the camera control unit 34 through the same type of transmission system as the image signal T ₂ , so it matches the phase of the image signal T ₂ . Therefore, synchronous signal processing can be performed without the need for phase correction. In this way, after detecting the effective signal and removing noise from the image signal _T2 , the processing circuit 37 converts it into a standard television signal and outputs it.

The buffer circuits 41 and 42 on the camera control section 34 side and the buffer circuit 39 on the head section 30 side
and 40 are designed to have the same characteristics, and the occurrence of non-uniformity here can be avoided. In addition, in response to environmental changes on the head section 30 side, if the characteristics of the solid-state image sensor 32 change significantly, for example, the signal T ₁ is extracted from the part where it is sent to the solid-state image sensor 32, and the image signal T ₂ and Similarly, the characteristics of the solid-state image sensor 32 may be affected. Furthermore, in the embodiment described above, the image signal _T2 is processed by the sample and hold circuit 36, but in a single-plate color solid-state image sensor using one solid-state image sensor integrated with a color filter, , a circuit that extracts multiple color signals by synchronous detection may be used.
The present invention can also be used in such circuits.

[Effects of the Invention] As described above, according to the present invention, the reference signal for driving the solid-state image sensor is sent back to the control unit together with the solid-state image sensor output signal, and the image sensor output is adjusted based on the sent back reference signal. By processing the signals, accurate signal processing can be performed with a simple and small-scale circuit configuration that is not affected by external influences that occur when the solid-state imaging device is remotely driven.

[Brief explanation of drawings]

FIG. 1 is a circuit diagram of a remotely driven solid-state imaging device illustrating an embodiment of the present invention, FIG. 2 is a circuit diagram of a conventional remotely driven solid-state imaging device, and FIG. 3 is a circuit diagram of a conventional remotely driven solid-state imaging device described above. FIG. 3 is a waveform diagram for explaining signal processing of the imaging device. 31... Optical system lens, 32... Solid-state imaging device, 33... Multi-core cable, 35... Synchronization and drive signal generation circuit, 36... Sample hold circuit, 37... Process circuit.

Claims (1)

[Claims of Claims] 1. A head unit incorporating a solid-state image sensor, a circuit for processing an image sensor output signal from the solid-state image sensor, and a synchronizer for outputting a readout transfer signal for driving the solid-state image sensor. and a camera control section with a built-in drive signal generation circuit, which is provided between the head section and the camera control section, transmits the image signal from the head section to the camera control section, and transmits the image signal from the camera control section. A remotely driven solid-state imaging device comprising a transmission path for transmitting the readout transfer signal to the head section, further comprising: means for sending a reference signal from the camera control section to the head section via the transmission path; means for sending the reference signal back from the head section to the camera control section via the transmission path; and sending the returned reference signal to the circuit as a timing signal for a circuit that processes the image sensor output signal of the camera control section. What is claimed is: 1. A remotely driven solid-state imaging device characterized by comprising: means for providing. 2. The remote controller according to claim 1, wherein the circuit that processes the image sensor output signal includes a circuit that samples and holds the image sensor output signal using the sent back reference signal. Drive type solid-state imaging device. 3. The remotely driven solid-state imaging device according to claim 1, wherein the reference signal is a pulse signal that is part of the readout transfer signal for driving the solid-state imaging device.