JPH10318835A - Optical sensor monitoring circuit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To optimize dynamic range in an optical sensor consisting of a plurality of elements, by monitoring peaks according to usage area. SOLUTION: An optical sensor circuit consisting of a plurality of photodiodes 11 -1n arranged like an array or area, operation amplifiers 21 -2n , integration capacities 31 -3n , first switches 41 -4n for resetting, is connected with a source follower circuit consisting of p-type transistors 51 -5n with a drain connected to the ground and constant current sources 61 -6n , and their outputs are connected with each other by a common monitor output wire 9 through second switches 71 -7n to obtain a monitor output MOUT of peak.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical sensor monitor circuit for monitoring an optical sensor having a plurality of charge accumulation type photoelectric conversion elements, which is used in an automatic focusing device such as a camera.

[0002]

2. Description of the Related Art Conventionally, as a sensor of an automatic focusing device such as a camera or the like, or a photometric device, a photosensor circuit having a charge storage type photoelectric conversion element arranged in an array or area is used. Is formed through a lens. In these photosensor circuits, photocharges are integrated for a certain period of time to obtain video data. In order to determine the integration time, data corresponding to the data of the optical sensor circuit having the largest light reception amount among the optical sensor circuits, that is, the output having the largest output, is monitored and output. Generally, such a monitor output is called a peak output. FIG. 9 shows a conventional optical sensor monitor circuit. This circuit photodiode ₁ 1 to 1 _n, the operational amplifier 2 ₁ to 2 _n and the integral capacitor 3 ₁ integrating circuit consisting to 3 _n to detect the optical switch 4 ₁ to 4 _n to reset the integration circuit, the operational amplifier 2 ₁ - Transistor 5 ₁ whose 2 _n output is input to the gate and whose drain is connected to GND
To 5 _n , a constant current source 6 for a circuit for monitoring the above-mentioned peak.
It is composed of Circuitry for monitoring the peak, the output of the operational amplifiers 2 ₁ to 2 _n is input to the source follower circuit formed by the transistors 5 ₁ to 5 _n, it is equivalent to that connect the respective output.

Next, the operation of the conventional circuit will be described. motion
Switch 4 as the beginning of₁~ 4_nIs turned on. Then each
Operational amplifier 2 for optical sensor circuit₁~ 2_nOutput is V_REFTona
And the monitor output M_OUTIs (V_REF+ Pch Transge
Star V_thValue). Then switch
4₁~ 4_nAre turned off at the same time, the photodiode 1
₁~ 1_nThe photocharges generated by₁~ 3_nTo
Integrated operational amplifier 2 ₁~ 2_nOutput of each
Photodiode 1₁~ 1_nFalls according to the amount of light received
You. Then, the monitor output M_OUTIs operational amplifier 2₁~ 2_nof
Follows the maximum value of the output (in this case, the output that drops the most)
And descend.

[0004]

Conventionally, one-point distance measurement is mainly used for cameras, and sensor data (integrated data of each pixel) used for distance measurement is data of all sensor areas. Therefore, the entire sensor area is appropriate for the sensor area to be monitored. However, recently, multi-point distance measurement has become common for cameras, and the number of pixels constituting a sensor has become larger than before.
In accordance with the direction in which the distance is measured, the sensor data of a part of the sensor area is used instead of using the entire area of the sensor. Therefore, monitoring the entire sensor area in the same manner as in the related art, if a peak is found in an area not used for distance measurement, if the integration time is set based on the peak monitor output, the actual There has been a problem that a dynamic range of a region to be used for distance measurement cannot be sufficiently obtained.

[0005]

In order to solve the above-mentioned problems, the invention according to claim 1 is directed to an electric charge generated from a plurality of photoelectric conversion elements arranged in an array or area according to the amount of received light. Is converted to a voltage by a charge-to-voltage conversion circuit connected to each
The gate or drain of a P-type transistor connected to ND is input to the gate of an N-type transistor connected to V _DD , respectively, and the source or drain of each transistor is connected to a common constant current source to output the constant current source. In the optical sensor monitor circuit that monitors the maximum output value of the photoelectric conversion element, the transistor and the constant current source are connected for each charge-voltage conversion circuit, and the second switch is connected to the output side of each constant current source. A common monitor output line is connected via

According to a second aspect of the present invention, a charge generated from a plurality of photoelectric conversion elements arranged in an array or area according to the amount of received light is converted into a voltage by a charge-voltage conversion circuit connected to each element. The converted voltage is input to the gate of a P-type transistor whose drain is connected to GND or the gate of an N-type transistor whose drain is connected to _VDD , and a common constant current source is connected to the source or drain of each transistor. In the optical sensor monitor circuit that monitors the maximum output value of the photoelectric conversion element by extracting the output voltage of the constant current source, the transistor and the constant current source are connected for each charge-voltage conversion circuit, and the photoelectric conversion element and The charge-voltage conversion circuit is divided into a plurality of blocks, and each block has a block monitor on the output side of each constant current source. After connecting the line, characterized by being connected to a common monitor output line of each block monitor line via the second switch.

According to a third aspect of the present invention, a charge generated from a plurality of photoelectric conversion elements arranged in an array or an area according to the amount of received light is converted into a voltage by a charge-voltage conversion circuit connected to each element. The converted voltage is input to the gate of a P-type transistor whose drain is connected to GND or the gate of an N-type transistor whose drain is connected to _VDD , and a common constant current source is connected to the source or drain of each transistor. In the optical sensor monitor circuit that monitors the maximum output value of the photoelectric conversion element by extracting the output voltage of the constant current source, the transistors are connected to each of the charge-voltage conversion circuits, and the source or the drain of each transistor is connected to each of the transistors. A common constant current source is connected via a second switch.

According to a fourth aspect of the present invention, a charge generated from a plurality of photoelectric conversion elements arranged in an array or area according to the amount of received light is converted into a voltage by a charge-voltage conversion circuit connected to each element. The converted voltage is input to the gate of a P-type transistor whose drain is connected to GND or the gate of an N-type transistor whose drain is connected to _VDD , and a common constant current source is connected to the source or drain of each transistor. In the optical sensor monitor circuit that monitors the maximum output value of the photoelectric conversion element by extracting the output voltage of the constant current source, the transistors are connected to each of the charge-voltage conversion circuits, and the source or the drain of each transistor is connected to each of the transistors. After connecting to the common constant current source line via the second switch, the third switch is connected to the constant current source line. Characterized in that by connecting a plurality of constant current source through a switch.

According to a fifth aspect of the present invention, a charge generated from a plurality of photoelectric conversion elements arranged in an array or an area in accordance with the amount of received light is converted into a voltage by a charge-voltage conversion circuit connected to each element. The converted voltage is input to the gate of a P-type transistor whose drain is connected to GND or the gate of an N-type transistor whose drain is connected to _VDD , and a common constant current source is connected to the source or drain of each transistor. In the optical sensor monitor circuit that monitors the maximum output value of the photoelectric conversion element by extracting the output voltage of the constant current source, the transistor is connected for each charge-voltage conversion circuit, and the photoelectric conversion element and the charge-voltage conversion circuit are connected. Into multiple blocks and block the source or drain of each transistor for each block. After connecting to each other by a common line, characterized in that to connect each block common line and the entire common constant current source via a second switch.

According to a sixth aspect of the present invention, a charge generated from a plurality of photoelectric conversion elements arranged in an array or an area according to the amount of received light is converted into a voltage by a charge-voltage conversion circuit connected to each element. The converted voltage is input to the gate of a P-type transistor whose drain is connected to GND or the gate of an N-type transistor whose drain is connected to _VDD , and a common constant current source is connected to the source or drain of each transistor. In the optical sensor monitor circuit that monitors the maximum output value of the photoelectric conversion element by extracting the output voltage of the constant current source, the transistor is connected for each charge-voltage conversion circuit, and the photoelectric conversion element and the charge-voltage conversion circuit are connected. Into multiple blocks and block the source or drain of each transistor for each block. After being connected to each other by a common line, each block common line and the whole common constant current source line are connected via a second switch, and then a plurality of constant current sources are connected to the constant current source line via a third switch. It is characterized by being connected.

According to a seventh aspect of the present invention, in the second, fifth, or sixth aspect of the invention, the number of photoelectric conversion elements in each block is the same.

According to an eighth aspect of the present invention, in the second, fifth, or sixth aspect of the present invention, the photoelectric conversion device of the block formed by dividing the central portion of the photoelectric conversion elements arranged in an array or area is defined. The present invention is characterized in that the number of conversion elements is larger than the number of elements of a block partitioned and formed at an end.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows a first embodiment according to the first aspect of the present invention.
FIG. 3 is a circuit diagram showing the embodiment. The optical sensor monitoring circuit includes a photodiode 1 ₁ to 1 _n, the integrating capacitor and the operational amplifier 2 ₁ to 2 _n where a charge-voltage converter circuit where a plurality of photoelectric conversion elements arranged in an array or area shape 3 ₁ to 3 _n comprised from the integrating circuit, the first switch 4 ₁ to 4 _n, p-type transistor having a drain connected to a source follower circuit to GND 5 ₁ to reset the integration circuit
To 5 _n, the second switch 7 connected constant current source 6 ₁ to 6 _n of the source follower circuit, the output of the source follower circuit ₁
To _7-n, it is constituted by the second switch 7 ₁ to _7-n common monitor output line 9 connected to the other end of the output of the source follower circuit are connected to each other by a monitor output line 9,
It becomes the peak monitor output M _OUT .

Next, the operation of the circuit shown in FIG. 1 will be described. motion
First, the second switch 7₁~ 7_nOf, distance measurement
ON the second switch of the optical sensor circuit used for
You. Next, the first switch 4₁~ 4_nIs turned on. Do
And operational amplifier 2 of each optical sensor circuit₁~ 2_nOutput is V_REF
And the monitor output M_OUTIs V_REFPch tiger
V of transistor_thIt becomes a value almost close to the potential obtained by adding the value. So
After the first switch 4 ₁~ 4_nTurn off all at once
And photodiode 1₁~ 1_nThe photocharge generated by
Integral capacity 3₁~ 3_nOperational amplifier 2₁~ 2_nof
The output is the photodiode 1₁~ 1_nReceives light
It descends according to the amount of light. Then, the monitor output M_OUTIs
Operational amplifier 2₁~ 2_nIn the output of the second switch
Therefore, the one selected, that is, the second switch
The maximum value of the output of the operational amplifier
The output also descends. This
And specify the desired area and monitor the peaks in it.
It becomes possible. In addition, the monitored peak value
Based on the dynamic of the area that you actually want to use for ranging
It is possible to set a sufficient range.

FIG. 2 is a circuit diagram showing a second embodiment according to the second aspect of the present invention. In this embodiment, the connection of the monitor output unit in the embodiment of FIG. 1 is changed. Parts common to those in FIG. 1 are denoted by the same reference numerals, description thereof will be omitted, and different parts will be described. In the first embodiment shown in FIG. 1, all the second switches for peak selection are connected to each optical sensor circuit, but the sensor area actually used for distance measurement is about 3 to 7 elements. In many cases, it is sufficient to select an appropriate number of photosensor circuits as one block, even if the area cannot be specified in pixel units in order to monitor the peak output.

Therefore, in this embodiment, as shown in FIG. 2, m (n)
> M), and each block outputs the output of each source follower circuit to the block monitor lines 10 ₁ to 10 m.
After connecting to 10 _m, via a second switch 7 ₁ to _7-m for block selection, in which the configuration of connecting to a common monitor output line 9. In this embodiment, since the sensor area to be monitored can be selected in block units, the number of second switches for selecting the sensor area is reduced, and the size of the circuit for controlling the switch is also reduced. It will be small.

FIG. 3 is a circuit diagram showing a third embodiment according to the third aspect of the present invention. In the first embodiment shown in FIG. 1, a source follower circuit is connected to each optical sensor circuit. However, in this embodiment, this source follower circuit is used as a peak monitor circuit, and an input transistor of the source follower circuit is used. Is connected to each optical sensor circuit. That this circuit, the photodiode ₁ 1 to 1 _n, the operational amplifier 2 ₁ to 2 _n and the integral capacitor 3 ₁ integrating circuit consisting to 3 _n to detect the light, the first switch 4 ₁ to 4 _n to reset the integration circuit , the operational amplifier 2 ₁ to 2 _n output p-type transistor 5 ₁ to 5 _n whose drain is connected to the GND is input to the gate of, the p-type transistor 5
The second switch 7 ₁ to _7-n which are connected to a source of ₁ to 5 _n,
Constituted by the constant current source 6 connected in common to the other end of the second switch 7 ₁ to _7-n. In this embodiment, since a constant current source is not provided for each photosensor circuit, the degree of freedom in layout is improved when the photosensor circuit is designed with an LSI or the like.

FIG. 4 is a circuit diagram showing a fourth embodiment according to the fourth aspect of the present invention. The circuit of this embodiment is:
Photodiodes ₁₁ to 1 _n for detecting light, operational amplifier 2
_An integrating circuit including _{1 to} 2 _n and integrating capacitors 3 _{1 to} 3 _n , first switches 4 ₁ to 4 _n for resetting the integrating circuit, and an operational amplifier 2
₁ to 2 _n output p-type transistor 51 _to the drain is connected to the GND together is input to the gate of
5 _n, p-type transistor 5 ₁ to 5 second switch 7 ₁ to _7-n which are connected to the _n source of a constant current source connected in common to the other end of the second switch 7 ₁ to _7-n line 11, the third switch 8 ₁ to 8 _k connected in parallel to the constant current source line 11, the third
It is constituted by the switch 8 ₁ to 8 _k constant current source 6 ₁ to 6 _k which are connected to the other end of the.

[0019] This is because the third embodiment shown in FIG. 3 is a one across the constant current source, followability to the peak of the operational amplifier 2 ₁ to 2 _n the number of the light sensor circuit selected for monitoring output Is intended to improve a slight difference from the embodiment of FIG. That is, in this embodiment, left as an k = n, the second switch 7 ₁ to _7-n and the third
If in conjunction with the switch 8 ₁ to 8 _k are ON, the circuit becomes a circuit equivalent to the embodiment of FIG. 1, the operational amplifier 2 ₁ -
The followability to the _2n peak can be made similar to the circuit of the embodiment of FIG. However, originally, the followability of the peak slightly differs depending on the subject image formed on the sensor, and therefore it is not always necessary that k = n.

FIG. 5 is a circuit diagram showing a fifth embodiment according to the fifth aspect of the present invention. In this embodiment, the connection of the monitor output unit in the embodiment of FIG. 1 is changed, and the same parts as those in FIG.
The different parts will be described. The circuit of this embodiment is:
Similar to the embodiment of FIG. 2, a plurality of light sensor circuit is divided into blocks of m (n> m) as one block, the block common line to the source side of the p-type transistor 5 ₁ to 5 _n for each block 12 which are connected to each other after connecting, the common constant current source 6 across the blocks common line 12 ₁ to 12 _m via a second switch 7 ₁ to _7-m for block selection by ₁ to 12 _m . In this embodiment, since the sensor area to be monitored can be selected in block units, the number of the second switches for selecting the sensor area is reduced, and the size of the circuit for controlling the switch is also reduced. It will be small.

FIG. 6 is a circuit diagram showing a sixth embodiment according to the sixth aspect of the present invention. In this embodiment, a plurality of constant current sources are connected to the embodiment shown in FIG. 5. The same reference numerals are given to the parts common to FIG. 5, and the description will be omitted, and different parts will be described. In the figure, the right ends of the second switches 7 _{1 to} 7 _m for block selection are connected to a common constant current source line 13, and the constant current source lines 13.
To which are connected a third switch 8 ₁ to 8 _k constant current source 6 ₁ to 6 _k through. This circuit, similar to the embodiment of FIG. 4, it is possible to improve the followability to the peak of the operational amplifier 2 ₁ to 2 _n.

FIG. 7 is a diagram showing a seventh embodiment according to the seventh aspect of the present invention. This seventh embodiment is similar to FIG.
Of the second embodiment, the fifth embodiment of FIG. 5, and the sixth embodiment of FIG.
Is applied to an optical sensor circuit array of a phase difference detection system used in a general camera, and shows a method of dividing an optical sensor circuit when monitor detection is performed in block units. In the figure, an example of block division of each sensor in the sensor array for the left and the sensor array for the right is shown, in which the number of sensors constituting both arrays is n, and the number m of blocks to be divided is 5; When the block is divided equally, the number of sensors in the block is n /
It becomes 5. In this embodiment, since the number of photosensor circuits in each block is equal, when used as multipoint ranging,
The advantage is obtained that the entire viewing angle of the sensor with respect to the subject becomes uniform and the flexibility is maximized.

FIG. 8 is a diagram showing an eighth embodiment according to the eighth aspect of the present invention. This eighth embodiment is similar to FIG.
21 shows another method of dividing a block in the seventh embodiment. This embodiment is applied when the entire viewing angle is not used for distance measurement, and is applied when it is desired to control the viewing angle finely. That is, as shown in the drawing, the number of photosensor circuits in the block 3 at the center of the array is set to be six times the number of photosensor circuits in the blocks 1, 2, 4, and 5 at the end of the array to divide the block. did. By dividing in this manner, it becomes possible to cope with the light amount drop characteristic of the imaging lens, as compared with the case of dividing equally as shown in FIG.
To that extent, there is obtained an advantage that performance and usability are improved.

Although the number of blocks m is set to 5 in the seventh and eighth embodiments, the same applies to the case of other division numbers. In addition, these embodiments can be similarly applied to an optical sensor circuit configured in an area. In each of the embodiments shown in FIGS. 1 to 6, a P-type transistor having a drain connected to GND is used as a source follower circuit. However, an N-type transistor having a drain connected to _VDD is used as a source follower circuit. Can also be configured.

From these facts, according to each of the above-described embodiments, it is possible to specify an arbitrary area and monitor the peak in the area, and optimally set the dynamic range of the area actually used. be able to. As a result, when the present invention is used for distance measurement, by selecting a monitor area suitable for a sensor area to be used for distance measurement,
It is possible to control a more optimal integration time of a sensor area to be used for distance measurement.

[0026]

As described above, according to the first, third, and fourth aspects of the present invention, the use or non-use of each photoelectric conversion element is set by the second switch and is actually used. It is possible to monitor only the photoelectric conversion element that performs this operation.

According to the second, fifth and sixth aspects of the present invention, the individual photoelectric conversion elements are divided into blocks, and the use / non-use of the individual photoelectric conversion elements is determined in units of blocks by the second switch. With this setting, only the block including the photoelectric conversion element actually used can be monitored.

According to the seventh aspect of the present invention, by equalizing the number of photoelectric conversion elements in the block, when the present invention is used for multi-point distance measurement, the entire field of view of the sensor with respect to the subject becomes uniform, and the sensor is flexible. The advantage of maximum performance is obtained.

According to the eighth aspect of the present invention, since the number of photoelectric conversion elements in the block formed in the center portion is larger than that in the end blocks, setting corresponding to the detection characteristic based on the arrangement position of the elements is possible. Becomes

[Brief description of the drawings]

FIG. 1 is a circuit diagram showing a first embodiment according to the present invention.

FIG. 2 is a circuit diagram showing a second embodiment according to the invention described in claim 2;

FIG. 3 is a circuit diagram showing a third embodiment according to the third aspect of the present invention.

FIG. 4 is a circuit diagram showing a fourth embodiment according to the fourth aspect of the present invention.

FIG. 5 is a circuit diagram showing a fifth embodiment according to the fifth aspect of the present invention.

FIG. 6 is a circuit diagram showing a sixth embodiment according to the present invention.

FIG. 7 is a view showing a seventh embodiment according to the invention described in claim 7;

FIG. 8 is a diagram showing an eighth embodiment according to the invention described in claim 8;

FIG. 9 is a circuit diagram showing a conventional example.

[Explanation of symbols]

1 ₁ to 1 _n photodiode 2 ₁ to 2 _n operational amplifiers 3 ₁ to 3 _n integrating capacitor 4 ₁ to 4 _n first switch 5 ₁ to 5 _n p-type transistors 6,6 ₁ ~6 _k, 6 _n constant current sources 7 ₁ ~7 _m, 7 _n entire second switch 8 ₁ to 8 _k third switch 9 common monitor output line 10 ₁ to 10 _m block monitor line 11 a constant current source line 12 ₁ to 12 _m block common line 13 Common constant current source line

Claims (8)

[Claims] An electric charge generated from a plurality of photoelectric conversion elements arranged in an array or an area according to the amount of received light is converted into a voltage by a charge-to-voltage conversion circuit connected to each element, and the converted voltage is converted. , The gate of a P-type transistor whose drain is connected to GND or the gate of an N-type transistor whose drain is connected to _VDD , and a common constant current source connected to the source or drain of each transistor. In the optical sensor monitor circuit that monitors the maximum output value of the photoelectric conversion element by extracting the output voltage of the photoelectric conversion element, the transistor and the constant current source are connected for each charge-voltage conversion circuit, and the output side of each constant current source is connected to the transistor. An optical sensor monitor circuit, wherein a common monitor output line is connected via two switches. 2. A charge-voltage conversion circuit connected to each element converts charges generated from a plurality of photoelectric conversion elements arranged in an array or area according to the amount of received light, and converts the converted voltage. , The gate of a P-type transistor whose drain is connected to GND or the gate of an N-type transistor whose drain is connected to _VDD , and a common constant current source connected to the source or drain of each transistor. In the optical sensor monitor circuit that monitors the maximum output value of the photoelectric conversion element by extracting the output voltage of the photoelectric conversion element, the transistor and the constant current source are connected for each charge-voltage conversion circuit, and the photoelectric conversion element and the charge-voltage conversion circuit are connected. After dividing into multiple blocks and connecting a block monitor line to the output side of each constant current source for each block Light sensor monitoring circuit, characterized in that each block monitor line connected to a common monitor output line through the second switch. 3. A charge-voltage conversion circuit connected to each element converts charges generated from a plurality of photoelectric conversion elements arranged in an array or area according to the amount of received light, and converts the converted voltage. , The gate of a P-type transistor whose drain is connected to GND or the gate of an N-type transistor whose drain is connected to _VDD , and a common constant current source connected to the source or drain of each transistor. In the optical sensor monitor circuit that monitors the maximum output value of the photoelectric conversion element by extracting the output voltage of the photoelectric conversion element, the transistor is connected to each charge-voltage conversion circuit, and the second switch is connected to the source or the drain of each transistor. An optical sensor monitor circuit, wherein a common constant current source is connected via the light source. 4. A charge-to-voltage conversion circuit connected to each element converts charges generated from a plurality of photoelectric conversion elements arranged in an array or area according to the amount of received light, and converts the converted voltage. , The gate of a P-type transistor whose drain is connected to GND or the gate of an N-type transistor whose drain is connected to _VDD , and a common constant current source connected to the source or drain of each transistor. In the optical sensor monitor circuit that monitors the maximum output value of the photoelectric conversion element by extracting the output voltage of the photoelectric conversion element, the transistor is connected to each charge-voltage conversion circuit, and the second switch is connected to the source or the drain of each transistor. Connected to a common constant current source line via a third switch via a third switch. Light sensor monitoring circuit, characterized in that it is connected a constant current source. 5. A charge-voltage conversion circuit connected to each element converts charges generated from a plurality of photoelectric conversion elements arranged in an array or an area in accordance with the amount of received light, and converts the converted voltage. , The gate of a P-type transistor whose drain is connected to GND or the gate of an N-type transistor whose drain is connected to _VDD , and a common constant current source connected to the source or drain of each transistor. In the optical sensor monitor circuit that monitors the maximum output value of the photoelectric conversion element by extracting the output voltage of the photoelectric conversion element, the transistor is connected to each charge-voltage conversion circuit, and the photoelectric conversion element and the charge-voltage conversion circuit are divided into a plurality of blocks. The source or drain of each transistor is divided into blocks and the source or drain of each transistor is After connecting to the optical sensor monitoring circuit, characterized in that the connecting blocks common line and the entire common constant current source via a second switch. 6. A charge-voltage conversion circuit connected to each element converts charges generated from a plurality of photoelectric conversion elements arranged in an array or area according to the amount of received light, and converts the converted voltage. , The gate of a P-type transistor whose drain is connected to GND or the gate of an N-type transistor whose drain is connected to _VDD , and a common constant current source connected to the source or drain of each transistor. In the optical sensor monitor circuit that monitors the maximum output value of the photoelectric conversion element by extracting the output voltage of the photoelectric conversion element, the transistor is connected to each charge-voltage conversion circuit, and the photoelectric conversion element and the charge-voltage conversion circuit are divided into a plurality of blocks. The source or drain of each transistor is divided into blocks and the source or drain of each transistor is After that, each block common line and the whole common constant current source line are connected via a second switch, and then a plurality of constant current sources are connected to the constant current source line via a third switch. An optical sensor monitor circuit characterized in that: 7. The method according to claim 2, wherein the information is stored in the memory.
2. The optical sensor monitor circuit according to claim 1, wherein the number of photoelectric conversion elements in each block is the same. 8. The method of claim 2, claim 5, or claim 6.
In the optical sensor monitor circuit described above, the number of photoelectric conversion elements of a block formed by partitioning a central portion of the photoelectric conversion elements arranged in an array or an area is larger than the number of elements of a block partitioned at an end. An optical sensor monitor circuit characterized by many things.