JPH1022918A - Receiver for optical communication - Google Patents

Abstract

PROBLEM TO BE SOLVED: To track the positions of light sources and to realize desired optical communication by specifying a light-receiving element among elements arranged in a matrix form even if light signals are simultaneously made incident on the light-receiving element from the plural light sources. SOLUTION: In a light-receiving element array arranged in the matrix form, a horizontal scanning circuit 4 and a vertical scanning circuit 7 send signals showing the positions of switching MOSFETSW12 and 34 becoming in a on-state to a detection circuit 3 by the element receiving the light signals from the light sources. The detection circuit 3 specifies the position of the photodiode receiving light and informs a decoder 8 of it. The decoder 8 outputs the output signal of the element receiving the light signal to a terminal T by setting one of switching MOSFETS1-S4 to be the on-state based on the signal. Thus, even the light signals from the plural light sources can track the positions of the light sources, mutually read the output signals of the light-receiving elements and can execute optical communication with plural opposite stations.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical communication receiver for performing optical communication.

[0002]

2. Description of the Related Art A congestion information providing (VICS) service for transmitting congestion information to an automobile navigation device using a communication line such as FM data multiplex broadcasting,
Provision of leisure-related information using mobile phones,
About Nikkei Electronics May 20, 1996
It is described on pages 91 to 106 of the Japanese journal.

As optical space communication, there are known optical communication by an optical telephone shown in FIG. 7 and optical communication by an optical remote controller using infrared rays. In conventional optical communication, when a plurality of light sources are present, if each light source transmits an optical signal independently, interference may occur and a communication failure may occur. For this reason, interference with other devices is suppressed by changing the modulation method or monitoring each other and performing own communication when no other device is performing communication.

[0004]

In a conventional optical communication receiver, when optical signals from a plurality of light sources are simultaneously incident on a light receiving element, the optical signal from a desired light source cannot be received. There is a problem that optical signals from a plurality of light sources cannot be received simultaneously.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems of the prior art, and a first object of the present invention is to select an arbitrary light source from a plurality of light sources, and to provide an optical signal from the selected light source. An object of the present invention is to provide a small-sized optical communication receiver capable of tracking and receiving a signal.

A second object is to provide a small-sized optical communication receiver capable of simultaneously tracking and receiving optical signals from a plurality of light sources.

[0007]

According to a first aspect of the present invention, there is provided an optical communication receiver comprising: a light receiving element array in which light receiving elements for converting an optical signal into an electric signal are arranged in a matrix; and a plurality of light receiving elements arranged in the light receiving element array. A readout circuit A for reading out the output signal of the light-receiving element, a detection circuit for detecting the light-receiving element that has received the optical signal based on the readout signal from the readout circuit A, and an output signal of the light-receiving element detected by this detection circuit. And a readout circuit B for reading.

A light receiving element that has received an optical signal from a light source is specified, and an output signal (photoelectrically converted electric signal) of the light receiving element is read out by a readout circuit B, whereby the position of the light source is tracked and optical communication is performed. It can be carried out. When there is a single light source, the output signal of the light receiving element specified by the detection circuit can be constantly read, and optical communication can be performed by demodulating the output signal.

When there are a plurality of light sources, by specifying each light receiving element which has received the light signal from each light source, the output signal of each specified light receiving element can be read alternately, and the output signal is demodulated. By doing so, optical communication can be performed with a plurality of partner stations.

According to a second aspect of the present invention, there is provided an optical communication receiver, comprising: a light receiving element array having a multilayer structure in which light receiving elements for converting an optical signal into an electric signal are arranged in a matrix; A readout circuit A for reading out the output signal of the light-receiving element, a detection circuit for detecting the light-receiving element receiving the optical signal based on the readout signal from the readout circuit A, and another layer overlapping the light-receiving element detected by this detection circuit And a readout circuit B for reading an output signal of the light receiving element.

A light-receiving element that has received a light signal from the light source is specified, and an output signal (electrically converted electric signal) of a light-receiving element in another layer overlapping the light-receiving element is read out by a reading circuit B. And optical communication can be performed. When there is a single light source, the output signal of the light receiving element in another layer overlapping the light receiving element specified by the detection circuit can be constantly read, and optical communication can be performed by demodulating the output signal.

Since the light receiving element array has a multilayer structure, if there are a plurality of light sources, each light receiving element that has received an optical signal from each light source is identified, so that the light receiving element of another layer positioned overlapping the light receiving element can be identified. Output signals can be read alternately, and optical communication with a plurality of partner stations can be performed by demodulating the output signals. Further, the area of the light receiving element array can be reduced, and the size can be reduced.

According to a third aspect of the present invention, there is provided an optical communication receiver, comprising: a light receiving element array in which light receiving elements for converting an optical signal into an electric signal are arranged in a matrix; and output signals of a plurality of light receiving elements arranged in the light receiving element array. Readout circuit A for reading out each light signal from each light source from a plurality of light sources.
And a plurality of readout circuits B for reading out the output signals of the respective light receiving elements detected by the detection circuit.

A light receiving element that receives an optical signal from the light source is specified, and an output signal (photoelectrically converted electric signal) of the light receiving element is read out by a readout circuit B, so that the position of the light source can be tracked to perform optical communication. It can be carried out. When there is a single light source, the output signal of the light receiving element specified by the detection circuit can be constantly read, and optical communication can be performed by demodulating the output signal.

Since a plurality of reading circuits B are provided, when there are a plurality of light sources, each light receiving element which has received an optical signal from each light source is specified up to the same number of light sources as the reading circuits B. The output signal of the element can be constantly read by each readout circuit B, and by demodulating the output signal, optical communication with a plurality of partner stations can be performed.

According to a fourth aspect of the present invention, there is provided an optical communication receiver, comprising: a light receiving element array having a multilayer structure in which light receiving elements for converting an optical signal into an electric signal are arranged in a matrix; A readout circuit A for reading out the output signals of the light-receiving elements, a detection circuit for detecting each light-receiving element that has received each optical signal from the plurality of light sources based on the readout signal from the readout circuit A, A plurality of readout circuits B for reading out output signals of light-receiving elements in other layers overlapping the respective light-receiving elements.

A light receiving element that has received an optical signal from the light source is specified, and an output signal (electrically converted electric signal) of a light receiving element in another layer overlapping the light receiving element is read out by a readout circuit B, so that the position of the light source is obtained. And optical communication can be performed. When there is a single light source, the output signal of the light receiving element in another layer overlapping the light receiving element specified by the detection circuit can be constantly read, and optical communication can be performed by demodulating the output signal.

Since the light receiving element array has a multi-layer structure and a plurality of readout circuits B are provided, when there are a plurality of light sources, the light sources from each light source are received up to the same number of light sources as the readout circuits B. By specifying the light receiving element, the output signal of the light receiving element of the other layer located overlapping with each light receiving element can be constantly read out by the readout circuit B, and the optical communication with a plurality of partner stations can be performed by demodulating the output signal. It can be carried out. Further, the area of the light receiving element array can be reduced, and the size can be reduced.

According to a fifth aspect of the present invention, in the optical communication receiver according to the first to fourth aspects, a light receiving element array and readout circuits A and B are provided.
And are integrally formed by a solid-state imaging device.

By using a CCD or MOS solid-state image pickup device, the light receiving element array and the readout circuits A and B can be made thinner, stacked, smaller, and lighter. By thinning the light receiving element array, when the light receiving element array has a multilayer structure, the light signal from the light source can be transmitted to the lower layer, and the optical signal can be transmitted not only from the upper light receiving element but also from the lower light receiving element. An electric signal obtained by photoelectric conversion can be obtained.

According to a sixth aspect, in the optical communication receiver according to the first or third aspect, the light receiving element array and the readout circuit A,
B is composed of a solid-state imaging device, and each pixel on the photoelectric surface of the solid-state imaging device is composed of a photodiode and two field-effect transistors.

The readout circuit A uses one field effect transistor when reading out the output signal of the photodiode as the light receiving element. The readout circuit B can always read out the output signal of the photodiode from the light receiving element array of one layer by using the other field effect transistor when reading out the output signal of the photodiode which is the light receiving element.

[0023]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described based on embodiments shown in the drawings.

The optical communication receiver 20 shown in FIG. 1 includes a light receiving element array 1 in which light receiving elements P for converting an optical signal into an electric signal are arranged in a matrix, and a plurality (four) of light receiving elements arranged in the light receiving element array 1. A reading circuit A for reading out the output signal of the light receiving element P, a detecting circuit 3 for detecting the light receiving element P that has received the optical signal based on the reading signal from the reading circuit A, and a light receiving element detected by the detecting circuit 3 A readout circuit B for reading out an output signal of P. The demodulation circuit 6 further includes a demodulation circuit 6 for demodulating a readout signal from the readout circuit B, and a speaker SP for outputting the demodulated information as audio. The symbol T is a terminal. Various information processing circuits may be provided instead of the speaker SP or together with the speaker SP. The optical communication receiver 20 is installed on a moving body such as a vehicle, for example.

The optical communication receiver 21 shown in FIG. 2 is a specific example of the optical communication receiver 20 shown in FIG. However, the demodulation circuit 6 and the speaker SP are omitted.

The photodiodes P1 to P4 correspond to the light receiving element P in FIG. The photodiodes P1 to P4 arranged in a matrix form the light receiving element array 1 of FIG. Vertical switching MOSFET
(Metal Oxide Semiconductor Field Effect Transisto
r) A1 to A4, horizontal scanning circuit 4, vertical scanning circuit 7
And horizontal switching MOSFETs SW12 and SW34
These constitute the readout circuit A of FIG. The decoder 8, the switching MOSFETs S1 to S4, and the switching MOSFETs B1 to B4 constitute the read circuit B of FIG.

The horizontal scanning circuit 4 is constituted by a shift register, and outputs a signal indicating the position of the horizontal switching MOSFET in the ON state to the detection circuit 3. For example, it outputs a control signal to the gates of the horizontal switching MOSFETs SW12 and SW34 to the detection circuit 3, respectively. The on-state horizontal switching MOSFET (drain thereof) outputs to the detection circuit 3 an electric signal from the photodiode that has passed through the on-state vertical switching MOSFET. The vertical scanning circuit 7 is constituted by a shift register, and outputs to the detection circuit 3 a signal indicating the position of the scanning line from which the pulse signal has been sent. For example, the pulse signal sent to each scanning line is output to the detection circuit 3.

The detection circuit 3 specifies a photodiode that has received an optical signal, for example, based on the potential level of a signal from the horizontal switching MOSFET in the ON state, and outputs a signal indicating this photodiode to the decoder 8. .

Since the gates of the switching MOSFETs B1 to B4 are fixed to the H level and turned on, the output signals of the photodiodes P1 to P4 are always supplied to the switching MOSFETs S1 to S4, respectively.

The decoder 8 turns on one of the switching MOSFETs S1 to S4 based on a signal from the detection circuit 3, and turns on the switching MOSFET S1
Outputs an output signal (photoelectrically converted electric signal) of the photodiode receiving the optical signal to the terminal T.

The optical communication receiver 22 of FIG. 3 is a specific example of the optical communication receiver 20 of FIG. However, the demodulation circuit 6 and the speaker SP are omitted.

This is because the switching MOSFETs B1 to B4 are not all turned on in the optical communication receiver 21 of FIG.
The ET is turned on.

In the optical communication receiver 22 shown in FIG. 3, the decoders 8x and 8y and the switching MOSFETs S1 to S4
And the switching MOSFETs B1 to B4 constitute the readout circuit B of FIG.

The detection circuit 3 specifies the photodiode that has received the optical signal, and outputs a signal indicating this photodiode to the decoders 8x and 8y. The decoder 8y switches the switching MOSFET B based on the signal from the detection circuit 3.
1, B3 or switching MOSFET B2, B
4 is turned on.

The decoder 8x turns on either the switching MOSFET S12 or the switching MOSFET S34 based on the signal from the detection circuit 3,
The switching MOSFET in the ON state outputs the output signal of the photodiode that has received the optical signal to the terminal T.

The optical communication receiver 30 shown in FIG. 4 includes a light receiving element array in which light receiving elements (not shown) for converting an optical signal into an electric signal are arranged in a matrix, and a plurality of light receiving elements arranged in a single layer light receiving element array. A readout circuit A for reading out the output signals of the (16) light-receiving elements, a detection circuit 3 for detecting the light-receiving elements receiving the optical signal based on the readout signal from the readout circuit A; A readout circuit B for reading out the output signal of the light receiving element or the light receiving element arranged in the light receiving element array 2 overlapping the light receiving element.

The light receiving element is composed of a photodiode, and each pixel 1c, 2c of the photocathode 1b, 2b has one photodiode (not shown) and one vertical switching MOSF.
ET (not shown). The photocathodes 1b and 2b overlap each other, and a photodiode (not shown) arranged in a matrix on the photocathodes 1b and 2b constitutes a light receiving element array having a multilayer structure. A readout circuit A is constituted by 16 vertical switching MOSFETs (not shown) on the photoelectric surface 1b, the horizontal scanning circuit 4, the vertical scanning circuit 7, and the four horizontal switching MOSFETs SW. Decoders 9x and 9y and four switching MOSs
The read circuit B is constituted by the FET 9s and the 16 vertical switching MOSFETs (not shown) on the photoelectric surface 2b.

The horizontal scanning circuit 4 outputs to the detection circuit 3 a signal indicating the position of the horizontal switching MOSFET in the ON state. The on-state horizontal switching MOSFET (drain) is the on-state vertical switching MOSFET
An electric signal from the photodiode passing through T is output to the detection circuit 3. The vertical scanning circuit 7 outputs to the detection circuit 3 a signal indicating the position of the scanning line from which the pulse signal has been sent.

The detection circuit 3 specifies a photodiode which has received an optical signal, for example, based on the potential level of a signal from a horizontal switching MOSFET, and outputs a signal indicating this photodiode to the decoders 9x, 9y.
The decoder 9y turns on a vertical switching MOSFET (not shown) of one line on the photoelectric surface 2b based on a signal from the detection circuit 3.

The decoder 9x turns on one of the four switching MOSFETs 9s based on a signal from the detection circuit 3, and sets the switching MOSFET FE in the on state.
T outputs an electrical signal obtained by photoelectrically converting the optical signal to a terminal T.

The optical communication receiver 31 shown in FIG. 5 is different from the optical communication receiver 30 shown in FIG. 4 in that a plurality (four) of readout circuits B for reading out the output signals of the photodiodes arranged on the photocathode 2b are provided. Things.

One of the readout circuits B has symbols C, D, E, F
, Four vertical switching MOSFETs (not shown) arranged in each pixel 2c, and decoders 10x and 10y
And two switching MOSFETs 10s, and the read signal is output to a terminal T1.

The other one of the readout circuits B has symbols G, H,
Four vertical switching MOSFETs (not shown) arranged in each pixel 2c at positions I and J, and decoders 11x,
11y, two switching MOSFETs 11s,
And the read signal is output to a terminal T2.

The other one of the readout circuits B includes symbols K, N,
Four vertical switching MOSFETs (not shown) arranged in the pixel 2c at the positions of R and U, and the decoders 12x and 1
2y and two switching MOSFETs 12s, and the read signal is output to a terminal T3.

The other one of the read circuits B has reference numerals V, W,
Four vertical switching MOSFETs (not shown) arranged in each pixel 2c at X and Y positions, and decoders 13x,
13y, two switching MOSFETs 13s,
, And the read signal is output to a terminal T4.

The read signal output to the terminals T1 to T4 is
The signal may be supplied to the terminal T via a selector, or may be supplied to four demodulation circuits.

Since the light receiving element array has a multilayer structure and a plurality of (four) readout circuits B are provided, when there are a plurality of light sources, the number of light sources of the readout circuit B (four) is equal to the number of light sources. By specifying each light-receiving element that has received the light signal, the electric signal that has been photoelectrically converted can be constantly read out by the readout circuit B from the light-receiving element on the photoelectric surface 2b of the other layer that overlaps with the light-receiving element. By demodulating the output signal, large-capacity optical communication can be performed in a wide band with a plurality of partner stations.

In the optical communication receivers 30 and 31 shown in FIGS. 4 and 5, the photocathode 1b, the horizontal scanning circuit 4, the vertical scanning circuit 7, and the switching MOSFET SW are connected using the image sensor 40 shown in FIG. You may comprise. You may comprise using CCD.

The optical communication receivers 20, 21, 22, 30,
The solid-state imaging device 31 may be used, or the detection circuit 3 may be separately provided by a CPU or the like. The solid-state imaging device may be made of polysilicon and have a thickness of several hundred angstroms. Further, each layer of the light receiving element array having a multilayer structure may have a thickness of several hundred angstroms. Infrared light may be used as the carrier of the optical signal, and a filter that transmits infrared light may be superimposed on the light receiving element array.
A lens may be used to form an image on the light receiving element array.

The reading circuit A may read the output signal of each light receiving element every 1/30 seconds. When there are a plurality of light sources, the detection circuit 3 may assign a priority to each of the detected light receiving elements based on the number of blinks of the optical signal within a predetermined time.
By doing so, the readout circuit B can read out the output signal from the light receiving element with the highest priority, and can output the readout signal to the terminal T in order from the important information. In this case, by supplying the output signal of the demodulation circuit to an information processing circuit such as a computer, the information processing circuit can perform information processing in order from important information. In addition, each light source can be more accurately tracked by this priority order.

The above embodiment is an example of the present invention, and the present invention is not limited to the above embodiment.

[0052]

According to the optical communication receiver of the first aspect, optical communication can be performed by tracking the position of the light source.
When there is a single light source, the output signal of the light receiving element specified by the detection circuit can be constantly read, and optical communication can be performed by demodulating the output signal.

When there are a plurality of light sources, the output signals of the respective light receiving elements which have received the optical signals can be read alternately.
Optical communication with a plurality of partner stations can be performed by demodulating the output signal.

According to the optical communication receiver of the second aspect,
Optical communication can be performed by tracking the position of the light source. When there is a single light source, the output signal of the light receiving element in another layer overlapping the light receiving element specified by the detection circuit can be constantly read, and optical communication can be performed by demodulating the output signal.

When there are a plurality of light sources, it is possible to alternately read out output signals of the light receiving elements of the other layers positioned so as to overlap the respective light receiving elements that have received the optical signal, and to demodulate the output signals to obtain a plurality of light sources. Optical communication can be performed with the partner station. Further, with the light receiving element array having a multilayer structure, the area of the light receiving surface (photoelectric surface) can be reduced, and the size can be reduced.

According to the optical communication receiver of the third aspect,
Optical communication can be performed by tracking the position of the light source. When there is a single light source, the output signal of the light receiving element specified by the detection circuit can be constantly read, and optical communication can be performed by demodulating the output signal.

When there are a plurality of light sources, up to the same number of light sources as the readout circuits B, the output signals of the respective light receiving elements which have received the light signals from each light source can be read out by the respective readout circuits B at all times. By demodulating the signal, optical communication with a plurality of partner stations can be performed.

According to the optical communication receiver of the fourth aspect,
Optical communication can be performed by tracking the position of the light source. When there is a single light source, the output signal of the light receiving element in another layer overlapping the light receiving element specified by the detection circuit can be constantly read, and optical communication can be performed by demodulating the output signal.

When there are a plurality of light sources, up to the same number of light sources as the readout circuit B, the output signals of the light-receiving elements of the other layers positioned so as to overlap the light-receiving elements that have received the optical signals from each light source are read out. , The optical communication can be performed with a plurality of partner stations by demodulating the output signal. Further, with the light receiving element array having a multilayer structure, the area of the light receiving surface (photoelectric surface) can be reduced, and the size can be reduced.

According to the optical communication receiver of the fifth aspect,
A light-receiving element array and a readout circuit A,
B can be made thinner, more laminated, smaller, and lighter. By thinning the light receiving element array, when the light receiving element array has a multilayer structure, the light signal from the light source can be transmitted to the lower layer, and the optical signal can be transmitted not only from the upper light receiving element but also from the lower light receiving element. An electric signal obtained by photoelectric conversion can be obtained.

According to the optical communication receiver of the sixth aspect,
The read circuit A uses one field-effect transistor, and the read circuit B uses the other field-effect transistor.
The output signal of the photodiode can be constantly read from the single-layer light receiving element array.

In a case where optical communication is performed by a moving body such as a vehicle, a light source of an optical communication receiver is directed toward a light source by a driving unit such as an actuator, thereby performing optical communication by tracking the light source. However, the control of the driving unit is complicated, and it is often difficult to track the light source. According to the optical communication receiver according to the present invention, when optical communication is performed between moving objects or between moving objects, a light source can be accurately tracked, and each light source can be accurately tracked even for a plurality of light sources. effective.

Further, since the optical communication receiver according to the present invention includes the light receiving element array and the readout circuit A, it can be used as a conventional image sensor (area sensor), and its application is wide. Further, in the optical communication receiver according to the second or fourth aspect, the light receiving element array in the uppermost layer and the readout circuit A can be configured using a conventional image sensor, and the manufacturing thereof can be simplified.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram of an optical communication receiver according to the present invention.

FIG. 2 is a simplified configuration diagram of an optical communication receiver according to the present invention.

FIG. 3 is a simplified configuration diagram of an optical communication receiver according to the present invention.

FIG. 4 is a simplified configuration diagram of an optical communication receiver according to the present invention including a light receiving element array having a multilayer structure.

FIG. 5 is a simplified configuration diagram of an optical communication receiver according to the present invention including a light receiving element array having a multilayer structure.

FIG. 6 is a basic configuration diagram of a conventional image sensor.

FIG. 7 is an overall configuration diagram of a conventional optical telephone.

[Explanation of symbols]

1, 2,... Light receiving element array, 1b, 2b.
2c: pixel, 3: detection circuit, 4: horizontal scanning circuit, 5: modulation circuit, 6: demodulation circuit, 7: vertical scanning circuit, 8, 8x,
8y, 9x, 9y, 10x, 10y, 11x, 11y,
12x, 12y, 13x, 13y... Decoder, 10s,
11s, 12s, 13s ... Switching MOSFET,
20, 21, 22, 30, 31, 60 ... optical communication receiver, 50 ... optical communication transmitter, A, B ... readout circuit, A1 to
A4, Q: vertical switching MOSFET, B1 to B
4, S1 to S4, S12, S34: Switching MOS
FET, L: light emitting element, M: microphone, P: light receiving element, P
1 to P4: photodiode, SP: speaker, SW,
SW12, SW34 ... horizontal switching MOSFET,
T, T1 to T4, Z ... terminals.

Claims (6)

[Claims] A light-receiving element array in which light-receiving elements for converting an optical signal into an electric signal are arranged in a matrix; a readout circuit (A) for reading output signals of a plurality of light-receiving elements arranged in the light-receiving element array; A detection circuit for detecting a light receiving element which has received a signal based on a read signal from the read circuit (A); and a read circuit (B) for reading an output signal of the light receiving element detected by the detection circuit. Optical communication receiver. 2. A light receiving element array having a multilayer structure in which light receiving elements for converting an optical signal into an electric signal are arranged in a matrix, and a readout circuit for reading output signals of a plurality of light receiving elements arranged in a single layer light receiving element array. (A), a detection circuit for detecting a light receiving element receiving an optical signal based on a read signal from the readout circuit (A), and an output of a light receiving element in another layer overlapping the light receiving element detected by the detection circuit. A readout circuit (B) for reading out a signal; 3. A light receiving element array in which light receiving elements for converting an optical signal into an electric signal are arranged in a matrix, a readout circuit (A) for reading out output signals of a plurality of light receiving elements arranged in the light receiving element array, A detection circuit that detects each light receiving element that has received each optical signal from the light source based on the readout signal from the readout circuit (A); and a plurality of output circuits that read out the output signals of each light reception element detected by the detection circuit. A readout circuit (B); 4. A light-receiving element array having a multilayer structure in which light-receiving elements for converting optical signals into electric signals are arranged in a matrix, and a readout circuit for reading output signals of a plurality of light-receiving elements arranged in a single-layer light-receiving element array. (A), a detection circuit that detects each light receiving element that has received each optical signal from a plurality of light sources based on a read signal from the read circuit (A), and a light detection element that is detected by the detection circuit. A plurality of readout circuits (B) for reading out output signals of light-receiving elements in another layer that overlap
And a receiver for optical communication. 5. The optical communication receiver according to claim 1, wherein said light receiving element array, said readout circuit (A), and said readout circuit (B) are constituted by solid-state imaging devices. 6. The solid-state imaging device comprises the light-receiving element array, the readout circuit (A), and the readout circuit (B), wherein each pixel on a photoelectric surface of the solid-state imaging device is a photodiode and a photodiode. 4. The optical communication receiver according to claim 1, wherein the receiver comprises one field effect transistor.