JPS63190476A - Photoelectric converter - Google Patents

Abstract

PURPOSE:To increase the degree of freedom for the design by providing plural number of selecting means selecting an optical sensor of a sensor block so as to suppress a drive frequency of a selection means per one sensor to a lower value even when high frequency operation is required because of many number of optical sensors. CONSTITUTION:n-set of output terminals of a sensor block 101 are connected to capacitors C11-C1n and connected in common to a signal output line 103 via transistors (TRs) T11-T1n. Pulses phi11-phi1n are given respectively to each gate of the TRs T11-T1n from a scanning circuit 105. Moreover, pulses phi1, phi2 are inputted to input terminals (a), (b) of the circuit 105. This is applied similarly to the sensor block 102. Since the scanning circuits 105, 106 are pro vided for the sensor blocks 101, 102, one scanning circuit has only to have n-set of operating frequency in case of the read of 2n-set of optical sensors and the degree of freedom of design is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a photoelectric conversion device in which a plurality of optical sensors are arranged and the output of the optical sensors is read out via a signal output line.

[Prior Art] FIG. 7 is a schematic circuit diagram of a conventional imaging device in which optical sensors are arranged in areas.

In the figure, optical sensors 30 arranged in an area are commonly connected row by row by horizontal lines 31, and the horizontal lines 31 are connected to a vertical scanning section 32. The output of this vertical scanning unit 32 allows the optical sensor 30 of an arbitrary line to
is selected.

Further, the optical sensors 30 are commonly connected to vertical lines 33 for each column, and each vertical line 33 is connected to a signal output line 34 via transistors T1 to Tn. Each gate'TL pole of the transistors T1 to Tn is connected to the horizontal shift register 3.
According to the timing of the output from the shift register 36, the transistors T1 to Tn are sequentially turned on. By this horizontal scanning, the optical information of the line selected by the vertical scanning section 32 is serially read out to the signal-output line 34 and outputted to the outside through the amplifier 37.

In such conventional devices, the number of horizontal pixels (
The number of optical sensors 30) is 200 to 500 pixels. Therefore, one scanning period in television is 63.57p
Considering sec, the operating frequency of the horizontal shift register 36 is 3 to 8 MHz. Technically, it is possible to adequately handle the number of pixels and frequency of this level using conventional devices.

[Problems to be Solved by the Invention] However, as the resolution of imaging devices increases, it is certain that the number of pixels in the horizontal direction will increase to 1024 or more. In this case, considering the above-mentioned television rate, the operating frequency of the horizontal shift register 36 will be about 16 MHz or more.

At such high frequencies, conventional circuit configurations have had the problem of severe design constraints and reduced yield.

[Means for Solving the Problems 1] A photoelectric conversion device according to the present invention includes a plurality of sensor blocks each including a desired number of optical sensors, and a plurality of selection means for selecting a desired combination of optical sensors of the sensor blocks. and a plurality of signal output lines for taking out the sensor signals of the selected optical sensors, and each of the signal output lines is commonly connected in a desired combination via an opening/closing means. shall be.

[Function] In this way, since a plurality of the selection means (for example, a scanning circuit such as a shift register) are provided, even if there are a large number of optical sensors and high frequency operation is required, the number of selection means per one can be reduced. The drive frequency can be kept low, and the degree of freedom in circuit design, semiconductor element pattern design, etc. can be increased.

In addition, since the signal output lines are connected through switching means, when a signal is taken out to the - signal output line, the opening/closing means for the signal output line is closed, and the other signal output lines are opened/closed. By leaving the means open, it is also possible to prevent a drop in the level of the signal taken out to the signal output line, and it becomes possible to easily configure a high-resolution, high-output imaging device.

[Example] EMBODIMENT OF THE INVENTION Below, one embodiment of the present invention will be described in detail using the drawings.

FIG. 1 is a schematic circuit diagram showing an embodiment of a photoelectric conversion device according to the present invention.

In this embodiment, sensor blocks 101 and 102 each consisting of n optical sensors are provided.

A sensor block is a collection of optical sensors, and when each block is formed separately, one
This concept includes cases where odd/even lines of one sensor group are shown, or odd/even photosensors on an arbitrary line are shown. In this embodiment, two sensor blocks are only illustrated separately for convenience of explanation.

In the figure, n output terminals of a sensor block 101 are connected to capacitors C1l to 01n, and are also commonly connected to a signal output line 103 via transistors Tli to T1n. Pulses φ11 to φ1 are applied from the scanning circuit 105 to each gate electrode of the transistors Tl 1 to T1n.
n input each. In addition, the input terminal a of the scanning circuit 105
Pulses φ1 and φ2 are input to and b, respectively.

The signal output line 103 is grounded via a transistor 7r1, and is connected to a transistor 10 serving as a switch means.
7 to the input terminal of the amplifier 109.

A pulse φC1 is input to the gate electrode of the transistor Tr1, and a small pulse S is input to the gate electrode of the transistor 107.
rl enters.

The sensor block 102 has a similar configuration.

That is, the n output terminals of the sensor block 102 are connected to the capacitors C21 to C2n, and are commonly connected to the signal output line 104 via the transistors T2LNT2n. Pulses φ21 to φ2 are applied from the scanning circuit 106 to each gate electrode of the transistors T21 to T2n.
n input each. In addition, the input terminal a of the scanning circuit 106
In contrast to the scanning circuit 105, pulses φ2 and φ1 are input to the pulses φ2 and φ1, respectively.

The signal output line 104 is grounded via a transistor Tr2, and is connected to a transistor 10 which is a switch means.
8 to the input terminal of the amplifier 109.

A pulse φC2 is input to the gate electrode of the transistor Tr2, and a pulse φsr2 is input to the gate electrode of the transistor 108(7).

Scanning circuits 105 and 106 in this embodiment perform the following operations.

FIG. 2 is a timing chart showing the operation of the scanning circuit.

The scanning circuits 105 and 106 are driven by two-phase pulses φ1 and φ2, respectively, and by connecting them as shown in FIG. 1, the pulse φ11 of the scanning circuit 105 is synchronized with the pulse φ1 as shown in the timing chart. ~φ
1n outputs.

Pulse φ21~ of the scanning circuit 106 in synchronization with pulse φ2
φ2n outputs. Therefore, pulses φ1 and φ2
Depending on the timing, scanning circuits 105 and 106 can be operated at desired timing or independently.

Note that each pulse φ is supplied from the driver 111,
The driver 111 outputs each pulse at a timing according to a clock signal from an oscillator 112.

In this embodiment, transistors 107 and 108 are used as the switching means, but of course analog switches or the like having low resistance when turned on may also be used.

Further, a configuration in which three or more sensor blocks are provided and their signal output lines are commonly connected to the input terminal of the amplifier 109 via a switch means is also within the scope of the present invention.

Next, the operation of this embodiment will be explained with reference to FIG.

FIG. 3 is a timing chart showing a first example of each pulse timing output from the driver 111.

In the figure, first, the pulse φsrl is set to a high level, the pulse φsr2 is set to a low level, and the transistor 107 is turned on and the transistor 108 is turned off.

In this state, the scanning circuit 105 outputs a pulse φ11,
Turn on the transistor Tit. As a result, the first sensor signal of the sensor block 101 is taken out from the capacitor C1l to the signal output line 103, and is outputted to the outside from the output terminal 110 through the transistor 107 and the amplifier 109.

At the same time, the pulse φC2 is set to high level to turn on the transistor Tr2. As a result, signal output line 1
04 residual charge is removed.

When the first sensor signal of the sensor block 101 is outputted to the outside in this way, the pulses φsr1 and φ
sr2 is inverted to low level and high level, respectively, and transistor 107 is turned off and transistor 108 is turned on.

In this state, the scanning circuit 106 outputs a pulse φ21,
Turn on transistor T21. As a result, the first sensor signal of the sensor block 102 is taken out from the capacitor C21 to the signal output line 104, and is outputted to the outside through the transistor lO8 and the amplifier 109.

At the same time, the pulse φC1 is set to high level to turn on the transistor Tr1. As a result, the previous signal charge remaining on the signal output line 103 is removed.

Similarly, the pulses φ12~ from the scanning circuit 105 are
φ1n and pulses φ22 to φ2 from the scanning circuit 106
According to n, the sensor signals of sensor blow, 101 and 102 are alternately and sequentially output to the outside.

At this time, since the transistor 107 and 10B from which no signal is read is OFF, the wiring capacitance of the signal output line from which the signal is read is substantially only the wiring capacitance Cw of the signal output line itself. For this purpose, each capacitance C of capacitors cit~C1n and C21~C2n is changed to C
If it is made sufficiently larger than w, the signal level from the sensor can be read without significantly decreasing.

Furthermore, since scanning circuits 105 and 106 are provided for each sensor block 101 and 102, even when reading out 2n optical sensors, one scanning circuit only needs to operate at the operating frequency of n optical sensors, which is a design problem. The degree of freedom increases.

In this embodiment, pulses φ1 and φ2 input to the scanning circuit
Depending on the timing, it is possible to perform the following driving.

FIG. 4 is a timing chart showing a second example of each pulse timing output from the driver 111.

The second example shows a case where the optical sensors of sensor blocks 101 and 102 are sequentially read out, that is, the pulse φS
Transistor 107 is turned on by r1 and φsr2
, while the transistor 108 is turned off, the scanning circuit 105 sequentially outputs pulses φ11 to φ1n to read out all sensor signals of the sensor block lot.
Similarly, transistor 107 is turned off and transistor 1 is turned off.
08 is turned ON and all sensor signals of the sensor block 102 are read out.

FIGS. 5 and 6 are timing charts showing third and fourth examples of each pulse timing output from the driver ill.

In this way, it is also possible to turn off one of the scanning circuits and read out only one sensor block.

[Effects of the Invention] As explained in detail above, the photoelectric conversion device according to the present invention is provided with a plurality of selection means for selecting the optical sensors of the sensor block, so the number of optical sensors is large and high frequency operation is required. Even in such a case, the driving frequency of each selection means can be kept low, and the degree of freedom in circuit design, semiconductor element pattern design, etc. can be increased.

In addition, since the signal output lines are connected through opening/closing means, when the signal is taken out to the - signal output line,
By closing the opening/closing means for the signal output line and leaving the opening/closing means for the other signal output lines open, it is possible to prevent a drop in the level of the signal taken out to the signal output line, which enables high-resolution, high-output imaging devices. can be easily configured.

[Brief explanation of the drawing]

FIG. 1 is a schematic circuit diagram showing one embodiment of a photoelectric conversion device according to the present invention. FIG. 2 is a timing chart showing the operation of the scanning circuit. FIG. 3 is a timing chart of each pulse output from the driver 111. A timing chart showing an example of i1. FIG. 4 is a timing chart showing a second example of each pulse timing output from the driver 111. 5 and 6 are timing charts showing third and fourth examples of each pulse timing output from the driver 111. FIG. FIG. 7 is a schematic circuit diagram of a conventional imaging device in which optical sensors are arranged in areas. 101.102-Fist/sensor block 103.104...Signal output line 105.106--Scanning circuit 107.108...Transistor (opening/closing means) 109
... Amplifier 110 ... Output terminal agent Patent attorney Jo Taira Yamashita Figure 2 Figure 3 @ Figure 4 Figure 5 Figure 6N

Claims (1)

[Claims] (1) A plurality of sensor blocks each consisting of a desired number of optical sensors, a plurality of selection means for selecting a desired combination of optical sensors of the sensor blocks, and a plurality of signals for extracting sensor signals of the selected optical sensors. An output line, and the signal output lines are commonly connected in a desired combination via opening/closing means.