Light detection device and light detection system

Abstract

A light detection device according to an embodiment of the present disclosure comprises: a first region corresponding to a first light-receiving element; a second region corresponding to a second light-receiving element; and a first pixel circuit capable of outputting a first digital signal based on a signal generated by the first light-receiving element. A portion of the first pixel circuit is provided in the first region. The other portion of the first pixel circuit is provided in the second region.

Description

Optical Detection Device and Optical Detection System

[0001] The present disclosure relates to an optical detection device and an optical detection system.

[0002] A device has been proposed that includes a pixel array having a plurality of pixels and a plurality of signal lines extending in a vertical direction for detecting light (Patent Document 1).

[0003] Japanese Unexamined Patent Application Publication No. 2019 - 47486

[0004] In an optical detection device, it is desirable to be able to reduce the number of signal lines.

[0005] It is desired to provide an optical detection device capable of suppressing the number of signal lines.

[0006] The optical detection device according to an embodiment of the present disclosure includes a first region corresponding to a first light - receiving element, a second region corresponding to a second light - receiving element, and a first pixel circuit capable of outputting a first digital signal based on a signal generated by the first light - receiving element. A part of the first pixel circuit is provided in the first region, and another part of the first pixel circuit is provided in the second region. The optical detection device according to an embodiment of the present disclosure includes a first region corresponding to a first light - receiving element, a second region corresponding to a second light - receiving element, a first AD conversion circuit capable of converting a signal based on the charge generated by the first light - receiving element into a first digital signal, and a first storage circuit capable of storing the first digital signal. The first AD conversion circuit is provided in the first region, and the first storage circuit is provided in the second region. The optical detection system according to an embodiment of the present disclosure includes a light source capable of irradiating light onto an object and an optical detection device that receives light from the object. The optical detection device has a first region corresponding to a first light - receiving element, a second region corresponding to a second light - receiving element, and a first pixel circuit capable of outputting a first digital signal based on a signal generated by the first light - receiving element. A part of the first pixel circuit is provided in the first region, and another part of the first pixel circuit is provided in the second region.

[0007] Figure 1 is a block diagram showing an example of a schematic configuration of a photodetection system according to the first embodiment of this disclosure. Figure 2 is a diagram showing an example of a planar configuration of a photodetector according to the first embodiment of this disclosure. Figure 3 is a diagram illustrating an example of the pixel configuration of a photodetector according to the first embodiment of this disclosure. Figure 4 is a diagram showing an example of the pixel configuration of a photodetector according to the first embodiment of this disclosure. Figure 5 is a diagram illustrating an example of the pixel configuration of a photodetector according to the first embodiment of this disclosure. Figure 6 is a diagram showing an example of the pixel configuration of a photodetector according to the first embodiment of this disclosure. Figure 7 is a diagram showing an example of the pixel configuration of a photodetector according to the first embodiment of this disclosure. Figure 8 is a diagram showing an example of the pixel configuration of a photodetector according to the first embodiment of this disclosure. Figure 9 is a diagram showing an example of the configuration of a photodetector according to the first embodiment of this disclosure. Figure 10 is a diagram showing an example of the configuration of a photodetector according to a comparative example of this disclosure. Figure 11 is a diagram showing an example of the configuration of a photodetector according to the first embodiment of this disclosure. Figure 12 is a diagram illustrating an example of a cross-sectional configuration of a photodetector according to the first embodiment of this disclosure. Figure 13 is a diagram illustrating an example of the pixel configuration of a photodetector according to the first embodiment of this disclosure. Figure 14 is a diagram illustrating an example of the pixel configuration of a photodetector according to the first embodiment of this disclosure. Figure 15 is a diagram illustrating an example of the planar configuration of a photodetector according to the first embodiment of this disclosure. Figure 16 is a diagram illustrating an example of the planar configuration of a photodetector according to the first embodiment of this disclosure. Figure 17 is a diagram illustrating an example of the configuration of a photodetector according to the first embodiment of this disclosure. Figure 18 is a diagram illustrating another example of the configuration of a photodetector according to the first embodiment of this disclosure. Figure 19 is a diagram illustrating another example of the configuration of a photodetector according to the first embodiment of this disclosure. Figure 20 is a diagram illustrating another example of the configuration of a photodetector according to the first embodiment of this disclosure. Figure 21 is a diagram illustrating an example of the pixel arrangement of a photodetector according to Modification 1 of this disclosure. Figure 22 is a diagram illustrating an example of the pixel arrangement of a photodetector according to Modification 1 of this disclosure. Figure 23 is a diagram illustrating an example of the configuration of a photodetector according to Modification 1 of this disclosure. Figure 24 is a diagram illustrating an example of the configuration of a photodetector according to Modification 2 of the present disclosure.Figure 25 is a diagram illustrating another configuration example of the photodetector according to Modification 2 of the present disclosure. Figure 26 is a diagram illustrating another configuration example of the photodetector according to Modification 2 of the present disclosure. Figure 27 is a diagram illustrating an example configuration example of the photodetector according to Modification 3 of the present disclosure. Figure 28 is a diagram illustrating an example configuration example of the photodetector according to Modification 3 of the present disclosure. Figure 29 is a diagram illustrating an example configuration example of the photodetector according to Modification 4 of the present disclosure. Figure 30 is a diagram illustrating an example configuration example of the photodetector according to Modification 5 of the present disclosure. Figure 31 is a diagram illustrating an example configuration example of the photodetector according to Modification 6 of the present disclosure. Figure 32A is a diagram illustrating an example of the pixel configuration example of the photodetector according to Modification 7 of the present disclosure. Figure 32B is a diagram illustrating an example of the pixel configuration example of the photodetector according to Modification 7 of the present disclosure. Figure 33 is a diagram illustrating an example configuration example of the photodetector according to Modification 7 of the present disclosure. Figure 34 is a diagram showing an example of the pixel arrangement of the photodetector according to Modification 7 of the present disclosure. Figure 35 is a diagram showing an example of the pixel arrangement of the photodetector according to Modification 7 of the present disclosure. Figure 36 is a diagram illustrating an example configuration of a photodetector according to Modification 7 of the present disclosure. Figure 37 is a diagram illustrating an example configuration of pixels in a photodetector according to a second embodiment of the present disclosure. Figure 38 is a diagram illustrating an example configuration of a photodetector according to a second embodiment of the present disclosure. Figure 39 is a diagram illustrating an example configuration of a photodetector according to Modification 8 of the present disclosure. Figure 40 is a diagram illustrating an example configuration of a photodetector according to Modification 9 of the present disclosure. Figure 41 is a diagram illustrating an example configuration of a photodetector according to Modification 10 of the present disclosure. Figure 42 is a diagram illustrating another example configuration of a photodetector according to Modification 10 of the present disclosure. Figure 43 is a block diagram illustrating an example of a schematic configuration of a vehicle control system. Figure 44 is an explanatory diagram showing an example of the installation positions of the external information detection unit and the imaging unit.

[0008] The embodiments of this disclosure will be described in detail below with reference to the drawings. The description will be in the following order: 1. First Embodiment 2. Second Embodiment 3. Example of Use 4. Application Example

[0009] <1. First Embodiment> Figure 1 is a block diagram showing an example of a schematic configuration of a photodetection system according to the first embodiment of the present disclosure. The photodetection system 300 includes a photodetector 1 and a light-emitting device 2. The photodetector 1 and the photodetection system 300 are configured as devices capable of performing imaging (i.e., imaging device, imaging system), devices capable of performing distance measurement (i.e., distance measuring device, distance measuring system), etc.

[0010] The light detection device 1 is a device capable of detecting incident light. The light detection device 1 has a plurality of pixels P, each containing a light-receiving element, and is configured to receive incident light and generate a signal. For example, the light detection device 1 receives light that has passed through an optical system (not shown) including an optical lens and generates a pixel signal.

[0011] The light detection device 1 is constructed using, for example, a substrate (such as a silicon (Si) substrate or a silicon on insulator (SOI) substrate) on which the light-receiving elements of each pixel P are provided. The light-receiving elements of the pixels P are, for example, avalanche diodes. The light detection device 1 receives light transmitted through the optical system and generates a signal. The light detection device 1 may have a structure (i.e., a laminated structure) formed by stacking multiple substrates (or semiconductor layers).

[0012] The light detection device 1 has a region (pixel section 100) where multiple pixels P are provided, as shown in the example in Figure 1. As an example, the light detection device 1 has a pixel section 100 in which multiple pixels P are arranged in a matrix in two dimensions. The pixel section 100 can also be described as a pixel array in which multiple pixels P are arranged. The number and arrangement of pixels P in the pixel section 100 can be arbitrarily set.

[0013] Each pixel P of the light detection device 1 includes, for example, an APD (Avalanche Photo Diode) as a light-receiving element and is configured to receive light and output an electric current. The light-receiving element of each pixel P is configured to generate a signal in response to the reception of photons. Each light-receiving element of each pixel P is a photoelectric conversion element, and can also be called a photoelectric conversion region.

[0014] Each pixel P may be composed of a SPAD (single-photon avalanche diode). The photodetector 1 captures incident light from the object to be measured through an optical system including an optical lens. The photodetector of the pixel P receives light from the object to be measured (e.g., visible light, infrared light, etc.), generates an electric charge through photoelectric conversion, and produces a photocurrent.

[0015] The light detection device 1 can be configured as an image sensor, a distance measuring sensor, etc. The light detection device 1 can be configured to perform distance measurement using the TOF (Time of Flight) method, for example. The light detection device 1 is a device that can receive light and generate a signal, and can also be called a light receiving device. The light detection device 1 can be used in various electronic devices such as digital still cameras, video cameras, and mobile phones.

[0016] The photodetector 1 and the photodetector system 300 can also be applied to sensors capable of detecting events, such as event-driven sensors (also known as EVS (Event Vision Sensor), EDS (Event Driven Sensor), DVS (Dynamic Vision Sensor), etc.). The photodetector and photodetector system according to this disclosure are applicable to a variety of electronic devices.

[0017] The light-emitting device 2 comprises a light source unit 200 and a control unit 210. The light source unit 200 is configured to generate light (optical signals). The light source unit 200 has, for example, one or more light-emitting elements and is configured to irradiate the object to be measured with light. The light-emitting elements are LDs (Laser Diodes), LEDs (Light Emitting Diodes), etc., and can output light (infrared light, visible light, etc.) to the outside.

[0018] The light source unit 200 (light source) generates laser light and emits it to the outside, as an example. The light source unit 200 may be configured using a semiconductor laser element, for example, a vertical cavity surface-emitting laser (VCSEL). The light-emitting device 2 has a light source unit 200 including a light-emitting element (i.e., a light-emitting region), and can also be called a light source device.

[0019] The control unit 210 is configured to control the light source unit 200. The control unit 210 is a control circuit and is configured to control the light-emitting elements of the light source unit 200. The control unit 210 can also be described as a drive unit (drive circuit) configured to drive the light source unit 200. The control unit 210 is composed of multiple circuits, including, for example, a timing generator, a DA conversion circuit (DAC: Digital to Analog Converter), and an amplifier circuit, and controls the operation of the light source unit 200.

[0020] The control unit 210 is configured to control, for example, the current and voltage supplied to the light-emitting elements of the light source unit 200. The control unit 210 supplies current and voltage to the light source unit 200 to drive the light-emitting elements and controls the light emission by the light-emitting elements (e.g., light emission timing, light emission duration, etc.). The control unit 210 can also be called a light source control unit or a light source drive unit.

[0021] The light detection system 300 can irradiate an object with light (e.g., laser light) using the light source unit 200 and receive the light reflected from the object. In the light detection device 1, for example, reflected light (backlight) reflected from the object to be measured is incident on the pixel unit 100, and an electrical signal corresponding to the reception of the reflected light is detected. The light detection system 300 can transmit and receive light and measure the distance to the object to be measured.

[0022] The light detection device 1 has, for example, multiple pixels available for imaging and captures an image of the subject to be measured. The light detection device 1 also has multiple pixels available for distance measurement and detects the distance to the subject to be measured. The light detection device 1 is configured to generate image data showing the image of the subject and image data relating to the distance to the subject to be measured (distance image data).

[0023] As an example, the light detection device 1 includes a pixel unit 100, a pixel control unit 110, a signal processing unit 120, and a control unit 130, as shown in Figure 1. At least a part of the light detection device 1 and the light-emitting device 2 may be configured integrally. For example, part or all of the control unit 130 and the control unit 210 may be configured integrally. The light source unit 200 may be provided in the light detection device 1 or outside the light detection device 1.

[0024] Furthermore, the light detection device 1 has a plurality of control lines Lc and a plurality of signal lines Ls. The control lines Lc are signal lines capable of transmitting signals to control pixels P, and are connected to the pixel control unit 110 and the pixels P of the pixel unit 100. The control lines Lc are configured to transmit, for example, control signals for reading signals from pixels P.

[0025] In the pixel section 100 (i.e., the pixel array), for example, multiple control lines Lc are wired for each pixel row, which is composed of multiple pixels P arranged horizontally (in the row direction). The control lines Lc include, for example, wiring that transmits signals to control the pixel circuits of the pixels P. The control lines Lc can also be called drive lines (or pixel drive lines) that transmit signals to drive the pixels P.

[0026] The signal line Ls is a signal line capable of transmitting signals from the pixel P, and is connected, for example, to the pixel P of the pixel unit 100 and the signal processing unit 120. The signal line Ls is electrically connected to the pixel P and is configured to transmit signals output from the pixel P. In the pixel unit 100, as an example, one or more signal lines Ls are wired for each pixel row, which is composed of multiple pixels P arranged vertically (in the column direction).

[0027] The pixel control unit 110 is configured to control each pixel P of the pixel unit 100. The pixel control unit 110 is a control circuit (pixel control circuit) and is composed of multiple circuits, such as a buffer, a shift register, and an address decoder. The pixel control unit 110 generates a signal for controlling the pixels P and outputs it to each pixel P of the pixel unit 100 via a control line Lc. The pixel control unit 110 is controlled by the control unit 130 and controls the pixels P of the pixel unit 100.

[0028] The pixel control unit 110 generates signals to control pixels P, such as signals to control the pixel circuit of a pixel P, and supplies them to each pixel P via a control line Lc. The pixel control unit 110 can control the reading of pixel signals from each pixel P. The pixel control unit 110 can also be described as a pixel drive unit (pixel drive circuit) configured to drive each pixel P.

[0029] The control unit 130 is configured to control each part of the light detection device 1. The control unit 130 receives data such as a clock and operating mode commands from an external source, and can output data such as internal information of the light detection device 1. The control unit 130 is a control circuit and, for example, has a timing generator configured to generate various timing signals.

[0030] The control unit 130 controls the operation of the pixel control unit 110 and the signal processing unit 120, etc., based on various timing signals (pulse signals, clock signals, etc.) generated by the timing generator. The control unit 130 may include circuits such as a PLL (Phase Locked Loop) and a DAC (Digital to Analog Converter).

[0031] The control unit 130 is configured to control the operation of the control unit 210 by supplying signals to the control unit 210 for control of the control unit 210. The control unit 130 is configured to control the generation process of pixel signals by the pixels P of the pixel unit 100, the timing of light irradiation by the light source unit 200, and so on. The signals output from each pixel P are input to the signal processing unit 120 via the signal line Ls.

[0032] The signal processing unit 120 is a signal processing circuit and is configured to perform signal processing. The signal processing unit 120 is composed of circuits that perform various signal processing on the signals output from each pixel P. The signal processing unit 120 includes arithmetic circuits, memory circuits, etc. The signal processing unit 120 is configured to perform various signal processing, such as noise reduction processing, TD (Time to Digital) conversion processing, counting (cumulative) processing, and interpolation processing.

[0033] The signal processing unit 120 is configured to acquire signals from each pixel P and generate signals related to grayscale values ​​(grayscale signals) and signals related to the distance to the measurement target (distance signals). For example, the signal processing unit 120 is configured to perform various signal processing on the signals from each pixel P to generate image data showing the subject image, distance image data showing the distance to the measurement target, and so on.

[0034] The signal processing unit 120 can generate and output, for example, image data including a grayscale signal (i.e., grayscale value) for each pixel, and distance image data including a distance signal (i.e., distance value) for each pixel. The signal processing unit 120 and the control unit 130 may be configured as an integrated unit. The signal processing unit 120 and the control unit 130 may also include a processor and memory.

[0035] The signal processing unit 120 is configured to generate a signal (distance signal) relating to the distance to the object to be measured based on the pixel signal. For example, in the light detection system 300, the light source unit 200 repeatedly irradiates and stops light, and the reflected light is repeatedly detected by the pixels P. The signal processing unit 120 can generate and output distance image data including the distance signal for each pixel P by analyzing the pixel signals output sequentially from each pixel P.

[0036] The signal processing unit 120 includes, for example, a histogram generation unit and is configured to generate a histogram of the pixel signal. The histogram generation unit is configured, as an example, to generate a histogram for each pixel of the signal value of the pixel signal, i.e., a count value corresponding to the round-trip time of light. The histogram generation unit can generate data as histogram data relating to the correspondence between the count value corresponding to the round-trip time of light and the frequency (number) of the count value.

[0037] The histogram generation unit (histogram generation circuit) classifies the count values ​​for each predetermined interval (range), i.e., each class (BIN), and generates histogram data showing the distribution of count values ​​according to the distance to the measurement target. The signal processing unit 120 calculates (estimates) the distance to the measurement target based on the peak value (maximum value) in the histogram of the pixel signal values.

[0038] The signal processing unit 120 calculates, for example, the difference between the start time of light irradiation and the arrival time of reflected light, i.e., the round-trip time of light (time of flight), based on the pixel signal value (count value) where the frequency in the histogram of the pixel signal shows a peak value. The signal processing unit 120 is configured to calculate the distance between the light detection device 1 and the object to be measured using the calculated round-trip time.

[0039] The signal processing unit 120 calculates the distance to the object for each pixel and generates a distance signal related to the distance to the object. The distance to the object is determined based on the time it takes for light emitted from the light source unit 200 to be reflected by the object and reach the light detection device 1. The signal processing unit 120 generates distance image data including the distance signal for each pixel and can output it to the outside of the light detection device 1.

[0040] The pixel unit 100, pixel control unit 110, signal processing unit 120, control unit 130, etc., described above may be provided on a single substrate or on multiple substrates. The pixel control unit 110, signal processing unit 120, control unit 130, etc., may be provided, for example, as peripheral circuits in the peripheral region of the pixel unit 100. The light detection device 1 may have a laminated structure formed by stacking multiple substrates.

[0041] Figure 2 is a diagram showing an example of a planar configuration of a light detection device according to the first embodiment. Figure 2 shows an example of the arrangement of pixels P in the pixel section 100 of the light detection device 1. The pixel section 100 (i.e., pixel array) of the light detection device 1 is provided with a plurality of pixels P, each having a light-receiving element 10, arranged, for example, in the horizontal direction (X-axis direction) and the vertical direction (Y-axis direction). In the pixel section 100, the plurality of pixels P are arranged in a matrix in a two-dimensional arrangement.

[0042] The light detection device 1 includes, for example, a pixel P (referred to as pixel P1) that receives visible light and converts it into photoelectric energy, and a pixel P (referred to as pixel P2) that receives infrared light and converts it into photoelectric energy. Pixel P1 is configured to receive visible light in the light-receiving element 10 and generate a signal. Pixel P2 is an IR pixel and is configured to receive infrared light in the light-receiving element 10 and generate a signal.

[0043] The plurality of pixels P1 provided in the pixel section 100 of the light detection device 1 include, for example, a pixel P1r (R pixel) that receives and converts light in the red (R) wavelength range into photoelectric light, a pixel P1g (G pixel) that receives and converts light in the green (G) wavelength range into photoelectric light, and a pixel P1b (B pixel) that receives and converts light in the blue (B) wavelength range into photoelectric light.

[0044] In the light detection device 1, for example, pixels P1r (R pixels), P1g (G pixels), and P1b (B pixels) are each configured to be able to generate a pixel signal of the R component, a pixel signal of the G component, and a pixel signal of the B component. Also, pixel P2 (IR pixel) is configured to be able to generate a pixel signal of the IR component and can be used for distance measurement by the TOF method.

[0045] In the pixel unit 100, for example, as in the example shown in FIG. 2, a plurality of pixels P1r, a plurality of pixels P1g, a plurality of pixels P1b, and a plurality of pixels P2 are repeatedly arranged. As an example, pixel P2 is arranged by replacing a part of the Bayer - arranged RGB pixels. Note that the number and arrangement of pixels P1 and P2 can be arbitrarily set.

[0046] The pixel P of the light detection device 1 has a region (referred to as the element region 90) where circuit elements of the pixel are provided. The element region 90 is a region corresponding to the light - receiving element 10 of the pixel P. The element region 90 corresponds to, for example, one region when the pixel unit 100 is divided into regions for each pixel P or for every plurality of pixels P (that is, for every predetermined number of pixels P). The element region 90 can also be called a unit pixel region.

[0047] The pixel P of the light detection device 1 has a filter 24 as in the example shown in FIG. 2. The filter 24 is configured to selectively transmit light in a specific wavelength range of the incident light. The filter 24 is provided, for example, above the light - receiving element 10 for each pixel P or for every plurality of pixels P. The light - receiving element 10 of the pixel P receives light through the filter 24. The filter 24 is an RGB color filter, a filter that transmits infrared light, or the like.

[0048] In the example shown in FIG. 2, pixel P1r (R pixel) has a filter 24 that transmits red (R) light. The light - receiving element 10 of pixel P1r receives light in the red wavelength range and performs photoelectric conversion. Also, pixel P1g (G pixel) has a filter 24 that transmits green (G) light. The light - receiving element 10 of pixel P1g receives light in the green wavelength range and performs photoelectric conversion.

[0049] Pixel P1b (B pixel) has a filter 24 that transmits blue (B) light. The photodetector 10 of pixel P1b receives light in the blue wavelength range and performs photoelectric conversion. Also, for example, pixel P2 (IR pixel) has an infrared light-transmitting filter 24 (IR pass filter). Pixel P2 receives light in the infrared wavelength range and performs photoelectric conversion.

[0050] The filter 24 provided in the pixels P of the pixel section 100 may be a complementary color filter such as Cy (cyan), Mg (magenta), or Ye (yellow). A filter corresponding to W (white), that is, a filter that transmits light across the entire wavelength range of incident light, may also be provided. In the light detection device 1, the filter 24 may be omitted if necessary. For example, the filter 24 may not be provided in some of the pixels P of the light detection device 1.

[0051] In the light detection device 1 according to this embodiment, as will be described later, a part of the pixel circuit 20 of a predetermined pixel P is provided in the element region 90 of another pixel P. A part of the pixel circuit 20 of one pixel P and a part of the pixel circuit 20 of another pixel P are arranged to be swapped. This makes it possible to reduce, for example, the number of signal lines Ls provided in the pixel section 100.

[0052] As shown in Figure 2, the direction of incidence of light from the subject being measured is defined as the Z-axis direction, the left-right direction perpendicular to the Z-axis direction is defined as the X-axis direction, and the up-down direction perpendicular to both the Z-axis and X-axis directions is defined as the Y-axis direction. In subsequent figures, directions may also be indicated based on the direction of the arrows in Figure 2.

[0053] [Pixel Configuration] Figure 3 is a diagram illustrating an example of the pixel configuration of a light detection device according to the first embodiment. Figure 3 shows an example of the configuration of a pixel P1 of the light detection device 1. Pixel P1 has a light-receiving element 10 and a pixel circuit 20. The pixel circuit 20 is provided, for example, for each light-receiving element 10. Note that the pixel circuit 20 may be provided for multiple light-receiving elements 10.

[0054] The light-receiving element 10 is configured to receive light and generate a signal. The light-receiving element 10 is, for example, a SPAD (Single Photon Avalanche Diode) and has a multiplication region (multiplication section) capable of avalanche multiplication. The light-receiving element 10 can convert incident photons into electric charge and output an electrical signal (signal VK in the example shown in Figure 3) corresponding to the incident photons. The light-receiving element 10 can also be described as a photoelectric conversion element (photoelectric conversion section) configured to convert light into photoelectric energy.

[0055] The pixel circuit 20 is configured to output a signal based on the current of the photodetector 10. The pixel circuit 20 includes circuits for reading the signal based on the photocurrent flowing through the photodetector 10, such as a supply circuit 30, a detection circuit 40, a counter 50, and an output circuit 60. The configuration of the pixel circuit 20 is not limited to the illustrated example and can be changed as appropriate.

[0056] The light-receiving element 10 is electrically connected to, for example, the supply circuit 30 and the detection circuit 40. In the example shown in Figure 3, the cathode, which is one electrode of the light-receiving element 10, is electrically connected to node N1, which is connected to the supply circuit 30 and the detection circuit 40. The anode, which is the other electrode of the light-receiving element 10, is electrically connected to, for example, wiring, electrodes, etc., to which a relatively low voltage is supplied.

[0057] In the example shown in Figure 3, the anode of the photodetector 10 is electrically connected to the potential line L2, which serves as a power line. A voltage VSP is supplied to the anode of the photodetector 10 via the potential line L2, for example, from a power supply unit (i.e., a voltage source) capable of supplying voltage. The voltage VSP is, for example, a negative voltage.

[0058] The supply circuit 30 is configured to supply current and voltage to the light-receiving element 10. The supply circuit 30 (supply unit) is electrically connected to the potential line L1 and can supply current and voltage to the light-receiving element 10. The potential line L1 is a wire to which a predetermined potential (voltage) is supplied. In the example shown in Figure 3, the potential line L1 is a power line to which the power supply voltage VDD is supplied.

[0059] The supply circuit 30 is, for example, composed of a switch that electrically connects or disconnects the potential line L1 and the light-receiving element 10. The supply circuit 30 may also be composed of a current source capable of supplying current to the light-receiving element 10. The supply circuit 30 may also be composed of a resistive element. The supply circuit 30 can also be called a recharge circuit (recharge section) or a quench circuit (quench section).

[0060] A voltage greater than the breakdown voltage of the photodetector 10 can be applied between the cathode and anode of the photodetector 10 by the voltage supplied via the supply circuit 30 and the voltage VSP supplied by the potential line L2. In other words, the potential difference across the photodetector 10 can be set to a potential difference greater than the breakdown voltage.

[0061] When a reverse bias voltage greater than the breakdown voltage is applied to the photodetector 10, it becomes capable of operating in Geiger mode. In Geiger mode, the photodetector 10 can generate an avalanche multiplication phenomenon in response to the incidence of photons, potentially producing a pulsed current. At pixel P1, a signal VK corresponding to the photocurrent flowing through the photodetector 10 due to the incidence of photons is output to the detection circuit 40.

[0062] The supply circuit 30 supplies current to the photodetector 10, for example, when avalanche multiplication occurs and the potential difference between the electrodes of the photodetector 10 is small. The supply circuit 30 recharges the photodetector 10, making it capable of operating in Geiger mode again. The supply circuit 30 can recharge the charge in the photodetector 10 and recharge the voltage of the photodetector 10.

[0063] The detection circuit 40 is configured to generate and output a signal S1 based on the signal VK generated by the photodetector 10. The detection circuit 40 outputs a signal S1 which is a voltage signal based on the current of the photodetector 10. The detection circuit 40 can also be described as a generation circuit configured to generate a signal S1. The detection circuit 40 can output a signal S1 which is a pulse signal based on the voltage of the signal VK to the counter 50.

[0064] The counter 50 is configured to perform counting in response to an input signal. The counter 50 (counter circuit) is configured, for example, to be able to count signal S1 and to generate a signal Put based on the count value. The counter 50 counts the pulses of signal S1 and outputs a signal Put, which is a digital signal corresponding to the number of pulses of signal S1.

[0065] The output circuit 60 is configured to output a signal, which is a digital signal generated by the pixel P1. The output circuit 60 is configured, for example, using multiple switches. As an example, the output circuit 60 is electrically connected between the counter 50 and the signal line Ls, and outputs the signal, which is the signal from the counter 50, to the signal line Ls as the pixel signal of the pixel P1. The output circuit 60 can also be called a readout circuit.

[0066] Figure 4 shows an example of the pixel configuration of a light detection device according to the first embodiment. Figure 4 shows a more detailed example of the configuration of pixel P1 of the light detection device 1. The supply circuit 30 is configured, for example, using a transistor as a switch. The supply circuit 30 can also be called a connection circuit.

[0067] The supply circuit 30 is controlled by a signal input from a control circuit (for example, a pixel control unit 110 or a control unit 130) that controls the supply circuit 30. The supply circuit 30 (i.e., the connection circuit) is controlled, for example, to a low resistance state (i.e., a low impedance state) or a high resistance state (i.e., a high impedance state) in response to the signal voltage input from the control circuit.

[0068] In the example shown in Figure 4, the supply circuit 30 is composed of a transistor M1. Transistor M1 is, for example, a MOS transistor (MOSFET) having gate, source, and drain terminals. As an example, transistor M1 is a P-type transistor (e.g., a PMOS transistor).

[0069] One of the source and drain of transistor M1 is electrically connected to a potential line L1 to which the power supply voltage VDD is supplied, and the other of the source and drain of transistor M1 is electrically connected to the photodetector 10. The supply circuit 30 is controlled to be ON (conducting) or OFF (non-conducting) by, for example, the pixel control unit 110.

[0070] The supply circuit 30 electrically connects or disconnects the potential line L1 and the photodetector 10 based on the signal Sc1 input as a control signal. The supply circuit 30 is controlled by the signal Sc1, which is a pulse signal, and is configured to recharge the photodetector 10. For example, the signal Sc1, which is a pulse signal, is repeatedly input to the supply circuit 30, causing the supply circuit 30 to be turned on intermittently.

[0071] For example, the pixel control unit 110 outputs a signal Sc1 to the supply circuit 30 to control the timing of recharging the photodetector 10. The pixel control unit 110 performs intermittent recharging of the photodetector 10 by controlling the supply circuit 30, for example. The supply circuit 30 is turned on at predetermined intervals (time intervals) in response to the signal Sc1, and can perform periodic recharging of the photodetector 10.

[0072] The detection circuit 40 is configured to generate a signal S1 based on the signal VK input from the light-receiving element 10. The detection circuit 40 is configured, for example, using an inverter (INV). The detection circuit 40 has, for example, an input section 41 and an output section 42, and can output an inverted signal of the input signal.

[0073] In the example shown in Figure 4, the detection circuit 40 is composed of an INV circuit 45 (inverter circuit). The INV circuit 45 is composed of, for example, a PMOS transistor and an NMOS transistor connected in series between the potential line L1 and the reference potential line. As an example, the reference potential line is a wire to which a voltage VSS (e.g., 0V) is applied, i.e., a ground line (earthing wire).

[0074] The input section 41 of the detection circuit 40 is electrically connected, for example, to the cathode of the light-receiving element 10 and the supply circuit 30. In the example shown in Figure 4, the input section 41 of the detection circuit 40 (i.e., INV circuit 45) is electrically connected to node N1 which connects the light-receiving element 10 and the supply circuit 30. The signal VK from the light-receiving element 10 is input to the detection circuit 40.

[0075] The signal level of signal VK, that is, the voltage (potential) of signal VK, changes according to the current flowing through the photodetector 10. The detection circuit 40 outputs a low-level signal S1 when, for example, the voltage of signal VK is higher than a threshold. The detection circuit 40 also outputs a high-level signal S1 when the voltage of signal VK is lower than a threshold.

[0076] The detection circuit 40, which is the INV circuit 45, transitions the voltage of signal S1 from a low level to a high level when the voltage of signal VK becomes lower than the threshold voltage of the INV circuit 45 due to the reception of photons by the photodetector 10. Also, the detection circuit 40 transitions the voltage of signal S1 from a high level to a low level when the voltage of signal VK becomes higher than the threshold voltage of the INV circuit 45 due to the recharging of the photodetector 10 by the supply circuit 30.

[0077] The detection circuit 40 outputs the signal S1, which is a digital signal, to the counter 50. The configuration of the detection circuit 40 is not limited to the example described above and can be changed as appropriate. The detection circuit 40 may be composed of a buffer circuit, AND circuit, NAND circuit, OR circuit, NOR circuit, etc. The detection circuit 40 may also have a level conversion circuit (level shifter).

[0078] The counter 50 has multiple stages of flip-flops, as shown in the example in Figure 4, and is configured to count the signal S1. For example, the counter 50 counts in response to the signal S1 input from the detection circuit 40 and converts the signal S1 into a signal Put, which is a digital signal with a predetermined number of bits.

[0079] The output circuit 60 has a number of switches (SW) corresponding to the number of bits of the signal Pout to be transmitted. The output circuit 60 has, for example, a switch provided for each flip-flop of the counter 50. Each switch of the output circuit 60 is controlled on or off by a control signal input from the pixel control unit 110 via the control line Lc, as an example.

[0080] The output circuit 60 (i.e., the readout circuit) outputs a signal, which is a digital signal of a predetermined number of bits, to the signal line Ls as the pixel signal of pixel P1. For example, the signal, which is output from each pixel P1 selected and scanned by the pixel control unit 110, is input to the signal processing unit 120 (see Figure 1) via the signal line Ls.

[0081] Figure 5 is a diagram illustrating an example of the pixel configuration of a light detection device according to the first embodiment. Figure 5 shows an example of the configuration of a pixel P2 (i.e., an IR pixel) of the light detection device 1. The pixel P2 has a light-receiving element 10 and a pixel circuit 20. The pixel circuit 20 is provided, for example, for each light-receiving element 10.

[0082] The pixel circuit 20 of pixel P2, like that of pixel P1, includes a supply circuit 30, a detection circuit 40, a counter 50, and an output circuit 60. Furthermore, the pixel circuit 20 of pixel P2 also includes a selection circuit 70. Pixel P2 may also have an adder circuit 80. The adder circuit 80 is provided, for example, for each pixel P2 or for each group of pixels P2.

[0083] Pixel P2 has a circuit section 21 and a circuit section 22, for example, as shown in the example in Figure 5. For example, circuit section 21 includes a light-receiving element 10, a supply circuit 30, and a detection circuit 40. Circuit section 22 includes a counter 50, a selection circuit 70, and an output circuit 60. Note that circuit section 22 may also include an adder circuit 80.

[0084] Figures 6 and 7 show examples of the pixel configuration of a light detection device according to the first embodiment. Figure 6 shows an example of the configuration of the circuit portion 21 of pixel P2. Figure 7 shows an example of the configuration of the circuit portion 22 of pixel P2. The circuit portion 21 of pixel P2 includes a light receiving element 10, a supply circuit 30, and a detection circuit 40.

[0085] The detection circuit 40 for pixel P2 includes, for example, an INV circuit 45, a flip-flop 47, and an AND circuit 48, as shown in the example in Figure 6. The input section 41 of the INV circuit 45 is electrically connected, for example, to the cathode of the photodetector 10 and the supply circuit 30. The output section 42 of the INV circuit 45 is electrically connected to the flip-flop 47.

[0086] The INV circuit 45 receives a signal VK from the photodetector 10. For example, if the voltage of signal VK is higher than a threshold, the INV circuit 45 outputs a low-level signal V1. Also, if the voltage of signal VK is lower than a threshold, the INV circuit 45 outputs a high-level signal V1. The INV circuit 45 can output a signal V1 based on the voltage of signal VK to the flip-flop 47.

[0087] The flip-flop 47 receives a signal V1 from the INV circuit 45. The flip-flop 47 also receives a signal Sc2 from a control circuit that controls it, such as the pixel control unit 110 (or control unit 130). For example, the flip-flop 47 is configured to sample and output a data signal in response to the pulse signal Sc2.

[0088] For example, the flip-flop 47 samples signal V1 as a data signal in response to signal Sc2 as a clock signal (or enable signal), and outputs signal V2 based on signal V1. The flip-flop 47 can also capture and hold signal V1 in synchronization with signal Sc2, and output signal V2 corresponding to signal V1.

[0089] The AND circuit 48 receives, for example, a signal V2 from the flip-flop 47 and a signal Sc2 from the pixel control unit 110. The detection circuit 40 outputs a signal V2 corresponding to the reception of photons by the photodetector 10 as a signal S1 via the AND circuit 48. For example, the pixel control unit 110 outputs a signal Sc2 to the pixel P2 and controls the generation and output timing of the signal S1.

[0090] The circuit portion 22 of pixel P2 includes, for example, a plurality of counters 50 (counters 50a to 50n in the example shown in Figure 7) and a selection circuit 70, as shown in the example in Figure 7. The circuit portion 22 of pixel P2 has, as an example, a plurality of counters 50 corresponding to the number of BIN (i.e., detection period) settings.

[0091] The selection circuit 70 is configured to output the signal S1 from the circuit portion 21 of the pixel P2 to the selected counter 50 from among the multiple counters 50. The selection circuit 70 (selection unit) is configured to allow switching of the output destination of the signal S1. The selection circuit 70 is configured to include, for example, a shift register.

[0092] The selection circuit 70 is configured, for example, using multiple flip-flops and multiple AND gates, as shown in Figure 7. The selection circuit 70 outputs signal S1 to a counter 50 that is selected according to the clock signal BIN_CLK. Signal S1 is input to the counter 50 selected by the selection circuit 70, and a counting operation is performed according to signal S1.

[0093] In the light detection device 1, for example, the signal Put obtained by counting the signal S1 in the selected counter 50 is read out as the pixel signal of pixel P2 by the output circuit 60 (not shown in Figure 7). The signal Put output from each pixel P2 is input to the signal processing unit 120 (see Figure 1) via the signal line Ls.

[0094] Figure 8 shows an example of the pixel configuration of a light detection device according to the first embodiment. Figure 8 shows another example of the configuration of the circuit portion 22 of pixel P2. Pixel P2 has a plurality of counters 50, a selection circuit 70, and an addition circuit 80. The circuit portion 22 of pixel P2 may include an addition circuit 80 in addition to the plurality of counters 50 and the selection circuit 70.

[0095] The light detection device 1 has multiple operating modes, for example, a first mode and a second mode. As an example, in the first mode, the light detection device 1 performs a process of counting the output signal of each pixel P2. In the second mode, the light detection device 1 may perform a process of adding the output signals of multiple pixels P2 and counting the added signals.

[0096] The adder circuit 80 is provided for the circuit portion 21 of multiple pixels P2 (for example, four circuit portions 21) and is configured to output a signal S2 based on multiple signals S1. The adder circuit 80 is configured, for example, by an OR circuit and outputs a signal S2 obtained by adding multiple signals S1. The signal S2 is a signal based on the signals S1 of multiple pixels P2, and is, for example, a signal obtained by adding four signals S1.

[0097] The selection circuit 70 has, for example, a circuit portion 71 including a shift register and a plurality of selectors (multiplexers), and is configured to switch signal paths. The selectors of the selection circuit 70 are configured to output, for example, signal S1 or signal S2 to the counter 50. In the example shown in Figure 8, the selection circuit 70 can output signal S1 or signal S2 to the counter 50 based on signal s_mode.

[0098] In the first mode, for example, when the signal s_mode becomes high level, the selection circuit 70 outputs the signal S1 of pixel P2 to the counter 50. The counter 50 counts the signal S1 of pixel P2. The count of signal S1 generates the signal Put, and the signal Put, as the pixel signal of pixel P2, is output to the signal processing unit 120 (see Figure 1) by, for example, the output circuit 60 (not shown in Figure 8).

[0099] In the second mode, for example, when the signal s_mode becomes low level, the selection circuit 70 outputs signal S2 to the selected counter 50 from among the multiple counters 50. A signal Put is generated by the count of signal S2, and signal Put, as the pixel signal of pixel P2, is output to the signal processing unit 120 by, for example, the output circuit 60.

[0100] [Configuration of the light detection device] Figure 9 shows an example of the configuration of a light detection device according to the first embodiment. The light detection device 1 is configured such that a part of the pixel circuit 20 of a predetermined pixel P is located in the element region 90 of another pixel P. For example, each circuit of the pixel circuit 20 of a pixel P (supply circuit 30, detection circuit 40, counter 50, or output circuit 60, etc.) is provided in the regions of multiple pixels P, i.e., multiple element regions 90.

[0101] In the light detection device 1, for example, a part of the pixel circuit 20 of a pixel P of a specific color (e.g., a counter 50 and an output circuit 60) is provided in the element region 90 of another pixel P located next to that pixel P. As an example, of two adjacent pixels P, a part of the constituent circuit of one pixel P and a part of the constituent circuit of the other pixel P are swapped.

[0102] In the example shown in Figure 9, of the adjacent pixels P1r and P1g in the X-axis direction, the supply circuit 30 (supply circuit 30r) and detection circuit 40 (detection circuit 40r) of pixel P1r are provided in the element region 90 (element region 90r) of pixel P1r. In addition, the counter 50 (counter 50r) and output circuit 60 (output circuit 60r) of pixel P1r are provided in the element region 90 (element region 90g) of pixel P1g.

[0103] Of the adjacent pixels P1r and P1g in the X-axis direction, the supply circuit 30 (supply circuit 30g) and detection circuit 40 (detection circuit 40g) of pixel P1g are provided in the element region 90g of pixel P1g. In addition, the counter 50 (counter 50g) and output circuit 60 (output circuit 60g) of pixel P1g are provided in the element region 90r of pixel P1r.

[0104] In the light detection device 1, for example, other adjacent pixels P1r and P1g in the pixel section 100 are also arranged such that the counter 50r and output circuit 60r of pixel P1r are swapped with the counter 50g and output circuit 60g of pixel P1g. It can also be said that some of the circuit elements of pixel P1r are replaced by some of the circuit elements of pixel P1g.

[0105] Figure 10 shows an example configuration of a photodetector according to a comparative example. If, for all pixels, all the circuit elements of the pixel are provided within the element area of ​​that pixel, the number of signal lines Ls may increase in order to read out pixel signals separately from various pixels P (for example, R pixels, G pixels, B pixels, and IR pixels).

[0106] In the comparative example shown in Figure 10, for example, a total of four signal lines Ls are provided: Ls_r connected to pixel P1r of one pixel row, Ls_g1 connected to pixel P1g of one pixel row, Ls_g2 connected to pixel P1g of another pixel row, and Ls_ir connected to pixel P2 of another pixel row.

[0107] In the light detection device 1 according to this embodiment, as described above, a portion of the pixel circuit 20 of a predetermined pixel P is provided to be located in the element region 90 of another pixel P. This makes it possible to reduce the number of signal lines Ls provided in the light detection device 1. This makes it possible to suppress the increase in pixel size caused by an increase in the number of signal lines Ls.

[0108] By configuring the light detection device 1 as shown in the example in Figure 9, a common signal line Ls_g can be provided for multiple pixels P1g. A total of three signal lines Ls are provided: signal line Ls_g, signal line Ls_r, and signal line Ls_ir. Compared to the comparative example shown in Figure 10, the number of signal lines Ls can be reduced. The light detection device 1 can have a structure that is advantageous for pixel miniaturization.

[0109] In the example shown in Figure 9, for example, the signal line Ls_g extends in the Y-axis direction (vertical direction) and is provided for a pixel row including adjacent pixels P1r and P1g in the Y-axis direction. The signal line Ls_g is arranged for the element region 90r of pixels P1r and the element region 90g of pixels P1g that are adjacent in the Y-axis direction. For example, the signal line Ls_g extends in the Y-axis direction in the pixel section 100 and is electrically connected to the output circuit 60 of each of the multiple pixels P1g.

[0110] Figure 11 shows an example of the configuration of a light detection device according to the first embodiment. For example, a part of the pixel circuit 20 of pixel P1b is provided in the element region 90 of another pixel P. As an example, a counter 50 and an output circuit 60, which are part of the pixel circuit 20 of pixel P1b, are arranged in the element region 90 of a pixel P adjacent to pixel P1b in the X-axis direction or the Y-axis direction.

[0111] In the example shown in Figure 11, of the adjacent pixels P1b and P1g in the X-axis direction, the supply circuit 30 (supply circuit 30b) and detection circuit 40 (detection circuit 40b) of pixel P1b are provided in the element region 90 (element region 90b) of pixel P1b. In addition, the counter 50 (counter 50b) and output circuit 60 (output circuit 60b) of pixel P1b are provided in the element region 90g of pixel P1g.

[0112] Of the adjacent pixels P1b and P1g in the X-axis direction, the supply circuit 30g and detection circuit 40g of pixel P1g are provided in the element region 90g of pixel P1g. The counter 50g and output circuit 60g of pixel P1g are provided in the element region 90b of pixel P1b. In addition, other adjacent pixels P1b and P1g in the pixel section 100 may be arranged such that the counter 50b and output circuit 60b are swapped with the counter 50g and output circuit 60g.

[0113] By configuring the light detection device 1 as shown in the example in Figure 11, a common signal line Ls_g can be provided for multiple pixels P1g. A total of three signal lines Ls are arranged: signal line Ls_g, signal line Ls_b, and signal line Ls_ir, which reduces the number of signal lines Ls. This makes it possible to suppress an increase in the size of the pixels.

[0114] In the example shown in Figure 11, the signal line Ls_g extends in the Y-axis direction in a plan view (i.e., when viewed in the XY plane) and is provided for a pixel row including adjacent pixels P1b and P1g in the Y-axis direction. The signal line Ls_g is positioned for the element region 90b of pixels P1b and the element region 90g of pixels P1g that are adjacent in the Y-axis direction. For example, the signal line Ls_g extends in the Y-axis direction in the pixel section 100 and is electrically connected to the output circuit 60 of each of the multiple pixels P1g.

[0115] Furthermore, in this embodiment, the pixel signal of pixel P1g (G pixel), the pixel signal of pixel P1r (R pixel) or pixel P1b (B pixel), and the pixel signal of pixel P2 (IR pixel) can be read out individually (independently) by separate signal lines Ls. For example, it becomes possible to individually control the frame rate for capturing visible images and the frame rate for distance measurement using IR pixels.

[0116] The light detection device 1 is equipped with RGB pixels (pixels P1r, P1g, P1b) and an IR pixel (pixel P2), allowing for simultaneous (parallel) measurement of grayscale values ​​and distance measurement. The light detection device 1 can obtain an image showing the subject (e.g., an RGB image) and a distance image using the pixel signals of each pixel.

[0117] Figure 12 is a diagram illustrating an example of the cross-sectional configuration of a photodetector according to the first embodiment. Figures 13 and 14 are diagrams illustrating an example of the pixel configuration of a photodetector according to the first embodiment. The photodetector 1 may have, for example, a substrate 201 and a substrate 202, as shown in the example in Figure 12.

[0118] As an example, the photodetector 1 has a configuration in which a substrate 201 as a first layer (first layer) and a substrate 202 as a second layer (second layer) are stacked in the Z-axis direction. The substrate 201 (first layer) can also be called the first circuit layer. The substrate 202 (second layer) can also be called the second circuit layer.

[0119] Each of the substrates 201 and 202 is constructed using a semiconductor substrate such as a silicon substrate or an SOI substrate. Substrates 201 and 202 may be made of SiGe (silicon germanium), Ge, or other semiconductor materials. Substrates 201 and 202 may be made of compound semiconductor materials of the III-V group, etc.

[0120] Figures 15 and 16 are diagrams illustrating an example of the planar configuration of a photodetector according to the first embodiment. Figure 15 shows an example of the planar configuration of the substrate 201 of the photodetector 1. Figure 16 shows an example of the planar configuration of the substrate 202 of the photodetector 1.

[0121] In the example shown in Figure 12, the substrate 201 has a semiconductor layer 101 and a wiring layer 111. The substrate 202 has a semiconductor layer 102 and a wiring layer 121. For example, the semiconductor layer 101, wiring layer 111, wiring layer 121, and semiconductor layer 102 are provided from the side where light is incident.

[0122] The semiconductor layer 101 of the substrate 201 has opposing surfaces 11S1 and 11S2. Surface 11S2 is the surface opposite to surface 11S1. Surface 11S2 is, for example, a light-receiving surface (light incident surface). The semiconductor layer 102 of the substrate 202 has opposing surfaces 12S1 and 12S2. Surface 12S2 is the surface opposite to surface 12S1.

[0123] The surface 11S1 of semiconductor layer 101 and the surface 12S1 of semiconductor layer 102 are, for example, element formation surfaces on which elements such as transistors are formed. Each of the surfaces 11S1 of semiconductor layer 101 and 12S1 of semiconductor layer 102 is provided with a gate electrode, a gate insulating film (for example, a gate oxide film), etc. The element formation surfaces of semiconductor layers 101 and 102 are surfaces on which various circuit elements are provided, and can also be called circuit surfaces.

[0124] For example, a light-receiving element 10 for each pixel P is provided in the semiconductor layer 101. The light-receiving element 10 is provided between surfaces 11S1 and 11S2 of the semiconductor layer 101. The light-receiving element 10 has a multiplication region 14. For example, multiple light-receiving elements 10 are embedded in the semiconductor layer 101.

[0125] A wiring layer 111 is provided on the surface 11S1 side of the semiconductor layer 101. Similarly, a wiring layer 121 is provided on the surface 12S1 side of the semiconductor layer 102. The wiring layers 111 and 121 each include, for example, a conductive film and an insulating film, and have multiple wirings and multiple vias (also referred to as contacts).

[0126] Each of the wiring layers 111 and 121 has a configuration in which multiple wirings are stacked with an insulating film acting as an interlayer insulating film (interlayer insulating layer). Each of the wiring layers 111 and 121 is composed of, for example, two or more or three or more layers of wiring, and is provided as a multilayer wiring layer.

[0127] Each of the wirings in the wiring layers 111 and 121 may be formed using a metallic material such as aluminum (Al) or copper (Cu), or it may be made of other conductive materials. The interlayer insulating film may be formed using, for example, silicon oxide (SiO), silicon nitride (SiN), silicon oxynitride (SiON), or it may be made of other insulating materials.

[0128] In the example shown in Figure 12, the wiring layer 111 has an electrode C1, and the wiring layer 121 has an electrode C2. Multiple electrodes C1 are arranged in the wiring layer 111, and multiple electrodes C2 are arranged in the wiring layer 121. Electrodes C1 and C2 are electrodes formed using copper (Cu), for example.

[0129] Electrodes C1 and C2 are electrodes used for joining metal electrodes, and can also be called joining electrodes. Electrodes C1 and C2 may be made of metal materials other than copper (Cu), such as nickel (Ni), cobalt (Co), gold (Au), tin (Sn), etc., or other materials.

[0130] As an example, substrates 201 and 202 are bonded together by a junction between metal electrodes made of Cu (electrode C1, electrode C2), i.e., a Cu-Cu junction. In the photodetector 1, the circuit provided on substrate 201 and the circuit provided on substrate 202 are electrically connected via electrodes C1 and C2.

[0131] As an example, substrates 201 and 202 are stacked such that surfaces 11S1 and 12S1, on which elements such as transistors are formed by electrode bonding, face each other. That is, substrates 201 and 202 are bonded so that the surface of semiconductor layer 101 and the surface of semiconductor layer 102 face each other. Alternatively, substrates 201 and 202 may be stacked using bumps.

[0132] On the surface 11S2 side of the semiconductor layer 101, for example, a lens 25 and a filter 24 are provided. The lens 25 and filter 24 are stacked on the semiconductor layer 101 in the thickness direction perpendicular to the surface 11S2 of the semiconductor layer 101. The lens 25 and the filter 24 are provided on the side into which light from an optical system such as an imaging lens is incident, and the wiring layer 111 is provided on the side opposite to the side into which the light is incident.

[0133] The lens 25 is an optical component that focuses light and is also called an on-chip lens. The lens 25 (lens portion) is provided above the light-receiving element 10, for example, for each pixel P or for each of multiple pixels P. Light from the subject to be measured is incident on the lens 25, for example, through the optical system. The lens 25 guides the incident light toward the light-receiving element 10 side of the pixel P.

[0134] As described above, the filter 24 is a primary color (RGB) color filter, an infrared light-transmitting filter, etc. The filter 24 is provided above the light-receiving element 10 for each pixel P or for each set of pixels P. As an example, the filter 24 is formed between the lens 25 and the semiconductor layer 101. The light-receiving element 10 of the pixel P receives light incident on it through the lens 25 and the filter 24.

[0135] As shown in Figures 13 and 14, the light-receiving elements 10 for each pixel P1 and each pixel P2 are provided on the substrate 201. As shown in the example in Figure 15, the light-receiving elements 10 are provided in element regions 90 on the substrate 201. For example, the light-receiving element 10 for pixel P1r is located in element region 90r of the substrate 201, and the light-receiving element 10 for pixel P2 is located in element region 90ir of the substrate 201.

[0136] The light-receiving element 10 of pixel P1 is electrically connected to the pixel circuit 20 of pixel P1, which is provided on the substrate 202, via electrodes C1 and C2. Similarly, the light-receiving element 10 of pixel P2 is electrically connected to the pixel circuit 20 of pixel P2, which is provided on the substrate 202, via electrodes C1 and C2. Furthermore, the pixel circuits 20 of some of the pixels P1 and P2 of each color are provided in multiple element regions 90 on the substrate 202.

[0137] In the light detection device 1, for example, as shown in the example in Figure 16, the supply circuit 30r and detection circuit 40r for pixel P1r are provided in the element region 90r of the substrate 202, among the adjacent pixels P1r and pixel P1g in the X-axis direction. In addition, the counter 50r and output circuit 60r for pixel P1r are provided in the element region 90g of the substrate 202.

[0138] Furthermore, of the adjacent pixels P1r and P1g in the X-axis direction, the supply circuit 30g and detection circuit 40g for pixel P1g are provided in the element region 90g of the substrate 202. In addition, the counter 50g and output circuit 60g for pixel P1g are provided in the element region 90r of the substrate 202.

[0139] At least a portion of the pixel control unit 110, signal processing unit 120, control unit 130, etc. (see Figure 1) described above is provided on the substrate 202. The light detection device 1 may have a structure in which three or more substrates are stacked. The pixel control unit 110, signal processing unit 120, control unit 130, etc. may be provided on a single substrate or may be provided on multiple substrates.

[0140] The above describes an example of the configuration of the light detection device 1, but the configuration of the light detection device 1 is not limited to the example described above. For example, the detection circuit 40, counter 50, and output circuit 60 of the pixel circuit 20 of pixel P may be arranged in the element region 90 of another pixel P. Or, only the output circuit 60 of the pixel circuit 20 of pixel P may be arranged in the element region 90 of another pixel P.

[0141] Figure 17 is a diagram illustrating an example of the configuration of a photodetector according to the first embodiment. In the example shown in Figure 17, among the adjacent pixels P1r and P1g in the X-axis direction, the supply circuit 30r, detection circuit 40r, and counter 50r of pixel P1r are provided in the element region 90r of pixel P1r. In addition, the output circuit 60r of pixel P1r is provided in the element region 90g of pixel P1g.

[0142] Furthermore, in the example shown in Figure 17, among the adjacent pixels P1r and P1g in the X-axis direction, the supply circuit 30g, detection circuit 40g, and counter 50g of pixel P1g are provided in the element region 90g of pixel P1g. In addition, the output circuit 60g of pixel P1g is provided in the element region 90r of pixel P1r.

[0143] Figure 18 is a diagram illustrating another configuration example of the photodetector according to the first embodiment. In the example shown in Figure 18, of the adjacent pixels P1r and pixels P1g in the Y-axis direction, the supply circuit 30r and detection circuit 40r of pixel P1r are provided in the element region 90r of pixel P1r. In addition, the counter 50r and output circuit 60r of pixel P1r are provided in the element region 90g of pixel P1g.

[0144] Furthermore, in the example shown in Figure 18, of the adjacent pixels P1r and P1g in the Y-axis direction, the supply circuit 30g and detection circuit 40g of pixel P1g are provided in the element region 90g of pixel P1g. In addition, the counter 50g and output circuit 60g of pixel P1g are provided in the element region 90r of pixel P1r.

[0145] As shown in the example in Figure 18, by configuring the light detection device 1, a common control line Lc (control line Lc_g) can be provided for multiple pixels P1g. For example, a control line Lc_g can be provided that is connected to a pixel P1g in one pixel row, a control line Lc_r can be connected to a pixel P1r in another pixel row, and a control line Lc_ir can be connected to a pixel P2 in another pixel row.

[0146] In the example shown in Figure 18, for example, the control line Lc_g extends in the X-axis direction (horizontal direction) and is provided for a pixel row including adjacent pixels P1r and P1g in the X-axis direction. The control line Lc_g is positioned for the element region 90r of pixels P1r and the element region 90g of pixels P1g that are adjacent in the X-axis direction. For example, the control line Lc_g extends in the X-axis direction in the pixel section 100 and is electrically connected to the output circuit 60 of each of the multiple pixels P1g.

[0147] In the example shown in Figure 18, a total of three control lines Lc are arranged: control line Lc_g, control line Lc_r, and control line Lc_ir. This allows for a reduction in the number of control lines Lc provided in the light detection device 1. This also helps to prevent an increase in the size of pixels P1 and P2 due to an increase in the number of control lines Lc.

[0148] Figure 19 is a diagram illustrating another configuration example of the light detection device according to the first embodiment. In the example shown in Figure 19, the supply circuit 30ir and detection circuit 40ir of the left pixel P2 are provided in the element region 90ir of that pixel P2. The counter 50ir and output circuit 60ir of the left pixel P2 are provided in the element region 90r of the pixel P1r.

[0149] Furthermore, in the example shown in Figure 19, the supply circuit 30ir and detection circuit 40ir of the rightmost of the two pixels P2 are provided in the element region 90ir of that pixel P2. Also, the counter 50ir and output circuit 60ir of the rightmost pixel P2 are provided in the element region 90g of pixel P1g.

[0150] Figure 20 is a diagram illustrating another configuration example of the photodetector according to the first embodiment. The photodetector 1 may have the configuration shown in Figure 20. In the example shown in Figure 20, among a plurality of pixels P1 and pixels P2 arranged in the X-axis and Y-axis directions, the configuration circuits of some pixels P1 and some pixels P2 are arranged to be swapped.

[0151] By configuring the light detection device 1 as shown in the example in Figure 20, a common control line Lc_g can be provided for multiple pixels P1g, and a common control line Lc_ir can be provided for multiple pixels P2. This allows for a reduction in the number of control lines Lc, thereby preventing an increase in pixel size.

[0152] [Function and Effects] The light detection device according to this embodiment comprises a first region corresponding to a first light-receiving element (for example, the element region 90r of pixel P1r), a second region corresponding to a second light-receiving element (for example, the element region 90g of pixel P1g), and a first pixel circuit (for example, the pixel circuit 20 of pixel P1r) capable of outputting a first digital signal based on the signal generated by the first light-receiving element. A part of the first pixel circuit is provided in the first region. Another part of the first pixel circuit is provided in the second region.

[0153] In the light detection device 1 according to this embodiment, for example, a part of the pixel circuit 20 of pixel P1r is provided in the element region 90r of pixel P1r. Another part of the pixel circuit 20 of pixel P1r is provided in the element region 90g of pixel P1g. Therefore, the number of signal lines such as signal lines Ls and control lines Lc can be reduced. This makes it possible to realize a light detection device that can reduce the number of signal lines.

[0154] Next, modified examples of the present disclosure will be described. In the following, components similar to those in the above embodiments will be denoted by the same reference numerals, and their descriptions will be omitted as appropriate.

[0155] (Modification 1) Figures 21 and 22 show an example of pixel arrangement in a light detection device according to Modification 1 of the present disclosure. In the light detection device 1, for example, pixels P1r, pixels P1g, and pixels P1b may each be arranged in 2x2 pixel units. In the pixel section 100 of the light detection device 1, for example, four adjacent pixels P1r, four adjacent pixels P1g, and four adjacent pixels P1b are repeatedly arranged.

[0156] In the pixel section 100 (i.e., the pixel array), as an example, four 2x2 pixels P1r, four 2x2 pixels P1g, and four 2x2 pixels P1b are arranged according to the Bayer array. Pixel P2 (IR pixels) are arranged by replacing some of the Bayer-arranged RGB pixels, for example, as shown in the example in Figure 21 or Figure 22.

[0157] Figure 23 is a diagram illustrating an example of the configuration of a photodetector according to Modification 1. In the example shown in Figure 23, the supply circuit 30ir and detection circuit 40ir of one of the two pixels P2 are provided in the element region 90ir of that pixel P2. In addition, the counter 50ir and output circuit 60ir of the other pixel P2 are provided in the element region 90g of pixel P1g.

[0158] Furthermore, in the example shown in Figure 23, the supply circuit 30g and detection circuit 40g of one of the two pixels P1g are provided in the element region 90g of that pixel P1g. Also, the counter 50g and output circuit 60g of the other pixel P1g are provided in the element region 90ir of pixel P2. In this modified example, the same effects as in the embodiment described above can be obtained.

[0159] (Modification 2) Figure 24 is a diagram illustrating an example of the configuration of a photodetector according to Modification 2. Figure 24 shows an example of the cross-sectional configuration of the photodetector 1. The substrate 201 may have a structure in which a plurality of semiconductor layers (in the example shown in Figure 24, semiconductor layer 101, semiconductor layer 105) are stacked.

[0160] The substrate 201 includes, for example, a semiconductor layer 101, a semiconductor layer 105, a layer 106, and a wiring layer 111. The semiconductor layer 105 may, for example, be composed of a silicon layer (i.e., an active layer) in an SOI substrate. The layer 106 is provided, for example, as a wiring layer or an insulating layer.

[0161] For example, at least a portion of the above-described pixel circuit 20 (supply circuit 30, detection circuit 40, counter 50, output circuit 60, etc.) is provided on the semiconductor layer 105 of the substrate 201. As an example, the supply circuit 30 and the detection circuit 40 of the pixel circuit 20 may be arranged on the semiconductor layer 105, and the counter 50 and the output circuit 60 may be arranged on the substrate 202.

[0162] Figures 25 and 26 are diagrams illustrating another configuration example of the photodetector according to Modification 2. The photodetector 1 may have a structure in which three or more substrates are stacked. The photodetector 1 has, for example, a substrate 201, a substrate 202, and a substrate 203, as shown in the example in Figure 25 or Figure 26.

[0163] The photodetector 1, as an example, has a configuration in which a substrate 201 as a first layer (first tier), a substrate 202 as a second layer (second tier), and a substrate 203 as a third layer (third tier) are stacked in the Z-axis direction. The substrate 203 is made of a semiconductor substrate such as a Si substrate or an SOI substrate. However, the substrate 203 may be made of other semiconductor materials.

[0164] In the example shown in Figure 25, the substrate 203 has a semiconductor layer 103 and a wiring layer 131. The substrate 203 (third layer) can also be called a third circuit layer. In the example shown in Figure 25, the semiconductor layer 101, wiring layer 111, wiring layer 121, semiconductor layer 102, wiring layer 121, wiring layer 131, and semiconductor layer 103 are provided from the side where light is incident.

[0165] The semiconductor layer 103 of the substrate 203 has opposing surfaces 13S1 and 13S2. Surface 13S2 is the surface opposite to surface 13S1. Surface 13S1 of the semiconductor layer 103 is an element formation surface on which elements such as transistors are formed. A gate electrode, a gate insulating film, etc., are provided on surface 13S1 of the semiconductor layer 103. The element formation surface of the semiconductor layer 103 is the surface on which various circuit elements are provided, and can also be called a circuit surface.

[0166] A wiring layer 131 is provided on the surface 13S1 side of the semiconductor layer 103. The wiring layer 131 is located on the surface 12S2 side of the semiconductor layer 102. The wiring layer 131 includes, for example, a conductive film and an insulating film, and has a plurality of wirings and a plurality of vias. The wiring layer 131 has a configuration in which a plurality of wirings are stacked with an insulating film acting as an interlayer insulating film in between.

[0167] In the example shown in Figure 25, the wiring layer 122 has electrodes C3, and the wiring layer 131 has electrodes C4. Multiple electrodes C3 are arranged in the wiring layer 122, and multiple electrodes C4 are arranged in the wiring layer 131. Electrodes C3 and C4 are electrodes formed using copper (Cu), for example. Electrodes C3 and C4 can also be called bonding electrodes.

[0168] Substrates 202 and 203 are stacked, for example, by bonding between electrodes (electrode C3, electrode C4), such that surfaces 12S2 and 13S1 face each other. That is, substrates 202 and 203 are bonded so that the back surface of semiconductor layer 102 and the front surface of semiconductor layer 103 face each other. Alternatively, bumps may be used to stack multiple substrates.

[0169] The substrate 203 is provided with at least some of the above-mentioned pixel control unit 110, signal processing unit 120, control unit 130, etc. (see Figure 1). For example, the signal processing unit 120 and control unit 130 are provided on the substrate 203. The pixel control unit 110 may be provided on the substrate 203, or it may be provided on the substrate 201 or the substrate 202.

[0170] (Modification 3) Figure 27 is a diagram illustrating an example of the configuration of a photodetector according to Modification 3. The photodetector 1 may have a circuit shared by a plurality of pixels P (referred to as a shared circuit). In the photodetector 1, for example, a plurality of pixels P are configured to share a part of the pixel circuit 20, and the plurality of pixels P have a part of the pixel circuit 20 as a shared circuit.

[0171] In the pixel section 100 (pixel array) of the light detection device 1, for example, of two adjacent pixels P, one pixel P (pixel PA in Figure 27) and the other pixel P (pixel PB in Figure 27) share an output circuit 60 (i.e., a readout circuit). Pixels PA and PB are arranged, for example, adjacent to each other in the X-axis direction (or Y-axis direction).

[0172] Pixel PA and pixel PB are configured as mutually distinct pixels, for example, RGB pixels (pixels P1r, P1g, P1b) and IR pixels (pixel P2). Pixel PA has a light-receiving element 10 (light-receiving element 10A) and an element region 90 (element region 90A) corresponding to the light-receiving element 10A of pixel PA. Pixel PB has a light-receiving element 10 (light-receiving element 10B) and an element region 90 (element region 90B) corresponding to the light-receiving element 10B of pixel PB.

[0173] Of the pixel circuits 20 (pixel circuit 20A) of pixel PA, the supply circuit 30 (supply circuit 30A) and the detection circuit 40 (detection circuit 40A) are provided in the element region 90A of pixel PA. The counter 50 (counter 50A) of pixel PA is provided in the element region 90B of pixel PB, for example, as shown in the example in Figure 27.

[0174] Of the pixel circuits 20 (pixel circuit 20B) of pixel PB, the supply circuit 30 (supply circuit 30B) and the detection circuit 40 (detection circuit 40B) are provided in the element area 90B of pixel PB. In addition, the counter 50 (counter 50B) of pixel PB is provided in the element area 90A of pixel PA. The counter 50A of pixel PA and the counter 50B of pixel PB are arranged to be interchangeable.

[0175] The output circuit 60 shared by pixels PA and PB is provided, for example, in element region 90A and element region 90B. The output circuit 60 is provided across element region 90A and element region 90B, as schematically shown in Figure 27. The photodetector 1 may have a configuration in which three or more pixels P share the output circuit 60.

[0176] In the case of the photodetector 1 according to this modified example, the same effects as in the embodiment described above can be obtained. Furthermore, by sharing the circuit, it is possible to improve the area efficiency of each pixel P. Note that the configuration of the output circuit 60 (readout circuit) is not limited to the illustrated example and can be changed as appropriate.

[0177] The output circuit 60 may have a counter 55, as shown in the example in Figure 28. The counter 55 is configured as a high-order bit counter. For example, the output signal of counter 50A or the output signal of counter 50B is selectively input to the counter 55. The counter 50 (counter circuit) can count according to the input signal and output a signal indicating the count value.

[0178] (Modification 4) Figure 29 is a diagram illustrating an example of the configuration of a light detection device according to Modification 4. The light detection device 1 may have a plurality of pixels P (e.g., pixels PA, pixels PB) having different sizes. For example, the size of the light-receiving element 10B of pixel PB is larger than the size of the light-receiving element 10A of pixel PA, and the light-receiving area of ​​the light-receiving element 10B of pixel PB is larger than the light-receiving area of ​​the light-receiving element 10A of pixel PA.

[0179] In the light detection device 1, for example, as shown in the example in Figure 29, the element region 90A of pixel PA and the element region 90B of pixel PB have different sizes (area, width, etc.). For example, in a plan view (i.e., viewed in the XY plane), the area of ​​element region 90B is larger than the area of ​​element region 90A.

[0180] Of the pixel circuits 20A of pixel PA, the supply circuit 30A and the detection circuit 40A are provided in the element area 90A of pixel PA. Of the pixel circuits 20A, the counter 50A and the output circuit 60 (output circuit 60A) are provided in the element area 90B of pixel PB. The supply circuit 30B, detection circuit 40B, counter 50B, and output circuit 60 (output circuit 60B) of pixel PB are provided in the element area 90B of pixel PB.

[0181] As shown in the example in Figure 29, if the area of ​​element region 90A is smaller than the area of ​​element region 90B, a pixel circuit 20A with an area greater than or equal to the area of ​​element region 90A can be implemented by providing a portion of the pixel circuit 20A of the pixel PA in element region 90B. Furthermore, functional expansion (for example, improvement of dynamic range) is possible by using multiple pixels P of different sizes.

[0182] (Modification 5) Figure 30 is a diagram illustrating an example of the configuration of a photodetector according to Modification 5. In the photodetector 1, multiple element regions 90 may overlap each other. For example, in the photodetector 1, a light-receiving element 10A (for example, a light-receiving element of an RGB pixel) and a light-receiving element 10B (for example, a light-receiving element of an IR pixel) are arranged to be stacked on top of each other, and element region 90A and element region 90B are positioned to overlap each other.

[0183] The pixel PA supply circuit 30A, detection circuit 40A, counter 50A, and output circuit 60A, and the pixel PB supply circuit 30B, detection circuit 40B, counter 50B, and output circuit 60B are located, for example, in element region 90A. In this modified example, the stacked structure of the photodetector 10A and the photodetector 10B makes it possible to increase the pixel size and improve sensitivity.

[0184] (Modification 6) Figure 31 is a diagram illustrating an example of the configuration of a photodetector according to Modification 6. The photodetector 1 may be configured such that the element region 90 and the region of the pixel circuit 20 are different. For example, as shown in the example in Figure 31, each of the element region 90A and element region 90B is provided to extend in the X-axis direction, and each of the pixel circuit 20A and pixel circuit 20B is provided to extend in the Y-axis direction.

[0185] The light detection device 1 may have pixels P configured as phase difference pixels. Pixel P has, for example, light-receiving elements 10A and 10B arranged adjacent to each other in the Y-axis direction (or X-axis direction), as shown in the example in Figure 31, and is configured as a phase difference pixel (also called a phase difference detection pixel). Light that has passed through different regions of the optical system is received by the light-receiving elements 10A and 10B, and pupil division is performed.

[0186] The signal processing unit 120 (see Figure 1) of the light detection device 1 can, for example, obtain phase difference data by using the pixel signal based on the charge converted by the photodetector 10A and the pixel signal based on the charge converted by the photodetector 10B. By using the phase difference data, phase difference autofocus (AF) can be performed.

[0187] By configuring the light detection device 1 as shown in the example in Figure 31, the degree of freedom in pixel arrangement can be improved, and functionality can be expanded. For example, phase-difference pixels can be arranged while suppressing an increase in the number of wires. In addition, a part of the pixel circuit 20A and a part of the pixel circuit 20B may be arranged to be swapped.

[0188] (Modification 7) Figures 32A and 32B are diagrams illustrating an example of the pixel configuration of the light detection device according to Modification 7. A pixel P has a plurality of light-receiving elements 10, for example, light-receiving elements 10A and 10B, and is configured as a phase difference pixel (referred to as pixel Pz). The light detection device 1 may have a plurality of phase difference pixels (in Figure 32A or Figure 32B, pixels Pz1 and pixels Pz2).

[0189] Pixel Pz1 has two light-receiving elements 10A and 10B arranged adjacent to each other in the X-axis direction. Similarly, pixel Pz2 has two light-receiving elements 10A and 10B arranged adjacent to each other in the Y-axis direction. Pixels Pz1 and Pz2 may be arranged so as to be aligned in the Y-axis direction or so as to be aligned in the X-axis direction.

[0190] In the light detection device 1, for example, one lens 25 (e.g., an on-chip lens) is provided for the light-receiving elements 10A and 10B of pixel Pz1. Similarly, one lens 25 is provided for the light-receiving elements 10A and 10B of pixel Pz2. Pixels Pz1 and Pz2 may also have the aforementioned filter 24.

[0191] Figure 33 is a diagram illustrating an example of the configuration of a photodetector according to Modification 7. In the example shown in Figure 33, pixel Pz1 has photodetectors 10A and 10B that are adjacent to each other in the X-axis direction. Pixel Pz2 also has photodetectors 10A and 10B that are adjacent to each other in the Y-axis direction.

[0192] Pixel Pz1 has an element region 90A corresponding to the light-receiving element 10A and an element region 90B corresponding to the light-receiving element 10B. The element region 90A and the element region 90B of pixel Pz1 are located adjacent to each other in the X-axis direction. Furthermore, for example, pixel Pz1 has a pixel circuit 20A connected to the light-receiving element 10A and a pixel circuit 20B connected to the light-receiving element 10B.

[0193] Pixel Pz2 has an element region 90A corresponding to the photodetector 10A and an element region 90B corresponding to the photodetector 10B. The element region 90A and the element region 90B of pixel Pz2 are located adjacent to each other in the Y-axis direction. Furthermore, pixel Pz2 has a pixel circuit 20A connected to the photodetector 10A and a pixel circuit 20B connected to the photodetector 10B.

[0194] Of the pixel circuits 20A of pixel Pz1, the supply circuit 30A and the detection circuit 40A are provided in the element region 90A of pixel Pz1, and the counter 50A and the output circuit 60A are provided in the element region 90B of pixel Pz1. Also, of the pixel circuits 20B of pixel Pz1, the supply circuit 30B and the detection circuit 40B are provided in the element region 90B of pixel Pz1, and the counter 50B and the output circuit 60B are provided in the element region 90A of pixel Pz1.

[0195] In pixel Pz2, the supply circuit 30A, detection circuit 40A, counter 50A, and output circuit 60A of pixel circuit 20A are each provided in the element region 90A of pixel Pz2. Also in pixel Pz2, the supply circuit 30B, detection circuit 40B, counter 50B, and output circuit 60B of pixel circuit 20B are each provided in the element region 90B of pixel Pz2.

[0196] By configuring the light detection device 1 as shown in the example in Figure 33, a common signal line Ls can be provided for each output circuit 60A of pixel Pz1 and pixel Pz2, and a common signal line Ls can also be provided for each output circuit 60B of pixel Pz1 and pixel Pz2. The number of signal lines Ls provided in the light detection device 1 can be reduced. This makes it possible to shorten the readout time of the pixel signal and reduce the size of the pixel.

[0197] Figure 34 shows an example of pixel arrangement of a photodetector according to Modification 7. The photodetector 1 may have pixel rows 95 containing one or more pixels Pz. The pixel section 100, as an example, has pixel rows 95 in which pixels P as imaging pixels and pixels Pz as phase difference pixels are alternately provided. For example, multiple pixel rows 95 may be discretely provided across the entire surface of the pixel section 100.

[0198] In the light detection device 1, as schematically shown by the solid or dashed arrows in Figure 35, a portion of the pixel circuit 20 of the imaging pixel P and a portion of the pixel circuit 20 of the phase difference pixel Pz are arranged to be swapped. This makes it possible, for example, to share the signal lines Ls provided for each pixel Pz of the pixel section 100.

[0199] Figure 36 is a diagram illustrating an example of the configuration of a photodetector according to Modification 7. Of the pixel circuits 20 of a pixel P, the supply circuit 30 and the detection circuit 40 are provided in the element region 90 of the pixel P. The counter 50 and output circuit 60 of the pixel P are provided in the element region 90 (element region 90z) of the pixel Pz, for example, as shown in the example in Figure 36.

[0200] Of the pixel circuit 20 (pixel circuit 20z) of pixel Pz, the supply circuit 30 (supply circuit 30z) and the detection circuit 40 (detection circuit 40z) are provided in the element region 90z of pixel Pz. The counter 50 (counter 50z) and output circuit 60 (output circuit 60z) of pixel Pz are provided in the element region 90 of pixel P. Note that the configuration of pixel circuits 20 and 20z is not limited to the illustrated example and can be changed as appropriate.

[0201] <2. Second Embodiment> Next, a second embodiment of the present disclosure will be described. In the following, components similar to those in the embodiments described above will be denoted by the same reference numerals, and their descriptions will be omitted as appropriate.

[0202] Figure 37 is a diagram illustrating an example of the pixel configuration of a photodetector according to a second embodiment of the present disclosure. The pixel P includes a photodetector 10, a transistor TG, a floating diffusion FD, and a readout circuit 15. The pixel P also includes an AD conversion circuit 17 and a memory circuit 18.

[0203] The light-receiving element 10 is configured to receive light and generate a signal. The readout circuit 15 is configured to output a signal based on the photoelectrically converted charge. The AD conversion circuit 17 and the memory circuit 18 are provided, for example, for each pixel P or for each of a plurality of pixels P. Each of the plurality of pixels P provided in the pixel section 100 has, for example, the configuration shown in Figure 37.

[0204] The light-receiving element 10 is configured to generate electric charge through photoelectric conversion. In the example shown in Figure 37, the light-receiving element 10 is a photodiode (PD) that converts incident light into electric charge. The light-receiving element 10 generates an electric charge corresponding to the amount of light received through photoelectric conversion. The light-receiving element 10 is a photoelectric conversion element, and can also be called a photoelectric conversion region.

[0205] The transistor TG is configured to transfer the charge photoelectrically converted by the photodetector 10 to the floating diffusion FD. The transistor TG is a transfer transistor. The transistor TG is controlled by the signal STG and electrically connects or disconnects the photodetector 10 and the floating diffusion FD. The transistor TG can transfer the charge converted and stored by the photodetector 10 to the floating diffusion FD.

[0206] The floating diffusion FD is a storage unit and is configured to store the transferred charge. The floating diffusion FD can store the charge converted photoelectrically by the photodetector 10. The floating diffusion FD stores the transferred charge and converts it into a voltage corresponding to the capacitance of the floating diffusion FD. The floating diffusion FD can also be described as a storage unit capable of holding charge.

[0207] The readout circuit 15 is configured to read out pixel signals based on charge photoelectrically converted by the light-receiving element 10. The readout circuit 15 includes, as an example, a transistor AMP, a transistor SEL, and a transistor RST. The readout circuit 15 may also include a floating diffusion FD. The readout circuit 15 may also include a transistor TG.

[0208] The transistor amplifier is configured to generate and output a signal based on the charge stored in the floating diffusion FD. The transistor amplifier can generate and output a signal based on the charge converted by the photodetector 10. The gate of the transistor amplifier is electrically connected to the floating diffusion FD, and the voltage converted by the floating diffusion FD is input to it.

[0209] The drain of the transistor AMP is connected to a power line to which the power supply voltage (power supply voltage VDD in the example shown in Figure 37) is supplied. The source of the transistor AMP is connected to a signal line Lp via a transistor SEL, for example. The transistor AMP is an amplifying transistor.

[0210] The transistor AMP is configured to generate a signal based on the charge accumulated in the floating diffusion FD, that is, a signal based on the voltage of the floating diffusion FD, and output it to the signal line Lp. In the example shown in Figure 37, the transistor AMP outputs the signal "Out" as a pixel signal based on the charge photoelectrically converted by the photodetector 10.

[0211] The transistor SEL is configured to control the output of the pixel signal. The transistor SEL is a selection transistor. The transistor SEL is electrically connected in series with the transistor AMP. The transistor SEL is controlled by the signal SSEL and is configured to output the signal from the transistor AMP to the signal line Lp. The transistor SEL can control the timing of the pixel signal output.

[0212] The transistor SEL is configured to output a signal based on the charge converted by the photodetector 10. The transistor SEL outputs the signal Pot, which is the pixel signal of the pixel P, to the signal line Lp. The transistor SEL may also be electrically connected in series between the power line and the transistor AMP. The transistor SEL may be omitted if necessary.

[0213] The transistor RST is configured to reset the voltage of the floating diffusion FD. Transistor RST is a reset transistor. Transistor RST is electrically connected to a power line to which a power supply voltage (power supply voltage VDD in Figure 37) is supplied, and is configured to perform a reset of the charge of pixel P.

[0214] The transistor RST is controlled by the signal SRST and can reset the charge accumulated in the floating diffusion FD and reset the voltage of the floating diffusion FD. The transistor RST electrically connects the power line and the floating diffusion FD and discharges the charge accumulated in the floating diffusion FD. In addition, the transistor RST can reset the charge accumulated in the photodetector 10 via the transistor TG.

[0215] The transistors TG (transfer transistor), AMP (amplifier transistor), SEL (selection transistor), and RST (reset transistor) mentioned above are, for example, MOS transistors (MOSFETs) that have gate, source, and drain terminals.

[0216] In the example shown in Figure 37, transistors TG, AMP, SEL, and RST are each composed of NMOS transistors. The transistors in pixel P may be composed of PMOS transistors as needed. Pixel P may also be configured without transistor SEL.

[0217] The pixel control unit 110 (see Figure 1) of the light detection device 1 supplies control signals to the gates of transistors TG, SEL, RST, etc. of each pixel P via the control line Lc described above, and sets the transistors to an ON state (conducting state) or an OFF state (non-conducting state). Transistors TG, SEL, and RST, etc., are controlled on / off by the pixel control unit 110.

[0218] The multiple control lines Lc for each pixel row of the light detection device 1 include, as an example, wiring for transmitting the signal STG that controls transistor TG, wiring for transmitting the signal SSEL that controls transistor SEL, wiring for transmitting the signal SRST that controls transistor RST, and wiring for transmitting signals that control the AD conversion circuit 17 and the memory circuit 18.

[0219] The AD conversion circuit 17 is configured to perform AD (Analog to Digital) conversion and converts the input analog signal into a digital signal. The AD conversion circuit 17 is an ADC (Analog to Digital Converter). For example, the signal Pot, which is a pixel signal, is input to the AD conversion circuit 17 from the readout circuit 15.

[0220] The AD conversion circuit 17 performs AD conversion processing on the signal "Pot," which is an analog signal input from the readout circuit 15. The AD conversion circuit 17 (AD conversion unit) includes, for example, a comparator circuit and a counter, and converts the input pixel signal into a digital signal of a predetermined number of bits.

[0221] The AD conversion circuit 17 outputs the signal Pot, which has been converted into a digital signal, to the memory circuit 18. The memory circuit 18 is composed of, for example, a latch (latch circuit). The memory circuit 18 may be configured as a memory circuit and include multiple memories (memory cells). The memory circuit 18 stores (stores) the signal Pot, which is a pixel signal converted into a digital signal.

[0222] The pixel control unit 110 controls the readout circuit 15, AD conversion circuit 17, and memory circuit 18 of each pixel P to output the pixel signal (i.e., signal Out) of each pixel P to the signal line Ls. The signals output from each pixel P are input to the signal processing unit 120 (see Figure 1) via the signal line Ls.

[0223] Figure 38 is a diagram illustrating an example of the configuration of a light detection device according to a second embodiment. The light detection device 1 is configured such that a part of each circuit of a predetermined pixel P is located in the element region 90 of another pixel P. For example, the AD conversion circuit 17 and the memory circuit 18 of a pixel P are provided in separate regions of multiple pixels P, i.e., multiple element regions 90.

[0224] In the light detection device 1, for example, a memory circuit 18 which is part of a specific pixel P is provided in the element region 90 of another pixel P located next to that pixel P. As an example, in the pixel section 100, the memory circuit 18 of one pixel P (for example, pixel Pxa1 or pixel Pxa2 in Figure 38) and the memory circuit 18 of the other pixel P (for example, pixel Pxb1 or pixel Pxb2 in Figure 38) are provided in a swapped manner.

[0225] In the example shown in Figure 38, of the two adjacent pixels Pxa1 and Pxb1 in the X-axis direction, the AD conversion circuit 17 (AD conversion circuit 17a) of pixel Pxa1 is provided in the element region 90 (element region 90xa) of pixel Pxa1. The memory circuit 18 (memory circuit 18a) of pixel Pxa1 is provided in the element region 90 (element region 90xb) of pixel Pxb1.

[0226] Of the adjacent pixels Pxa1 and Pxb1 in the X-axis direction, the AD conversion circuit 17 (AD conversion circuit 17b) of pixel Pxb1 is provided in the element region 90xb of that pixel Pxb1. Furthermore, the memory circuit 18 (memory circuit 18b) of pixel Pxb1 is provided in the element region 90xa of pixel Pxa1.

[0227] In the light detection device 1 according to this embodiment, as described above, the memory circuit 18 of a predetermined pixel P is provided so as to be located in the element region 90 of another pixel P. This makes it possible to reduce the number of signal lines, such as the signal line Ls connected to the memory circuit 18, the AD conversion circuit 17, or the control line Lc connected to the memory circuit 18. This makes it possible to suppress the increase in pixel size caused by an increase in the number of signal lines.

[0228] [Function and Effects] The light detection device according to this embodiment comprises a first region corresponding to a first photodetector (for example, the element region 90xa of pixel Pxa1), a second region corresponding to a second photodetector (for example, the element region 90xb of pixel Pxb1), a first AD conversion circuit (for example, AD conversion circuit 17a) capable of converting a signal based on the charge generated by the first photodetector into a first digital signal, and a first storage circuit (storage circuit 18a) capable of storing the first digital signal. The first AD conversion circuit is provided in the first region. The first storage circuit is provided in the second region.

[0229] In the light detection device 1 according to this embodiment, for example, the AD conversion circuit 17a of pixel Pxa1 is provided in the element area 90xa of pixel Pxa1. Also, the memory circuit 18a of pixel Pxa1 is provided in the element area 90xb of pixel Pxb1. Therefore, the number of signal lines such as signal lines Ls and control lines Lc can be reduced. This makes it possible to realize a light detection device that can reduce the number of signal lines.

[0230] Next, modified examples of the present disclosure will be described. In the following, components similar to those in the above embodiments will be denoted by the same reference numerals, and their descriptions will be omitted as appropriate.

[0231] (Modification 8) In the above-described embodiment, an example of the configuration of the light detection device 1 was explained, but the configuration of the light detection device 1 is not limited to the example described above. For example, the memory circuit 18a of pixel Pxa1 may be arranged in the element region 90 of another pixel adjacent to pixel Pxa1 in the Y-axis direction. Also, for example, the memory circuit 18a of pixel Pxa1 may be arranged in the element region 90 of another pixel adjacent to pixel Pxa1 in an oblique direction.

[0232] Figure 39 is a diagram illustrating an example of the configuration of a photodetector according to Modification 3 of the present disclosure. The AD conversion circuit 17 of pixel P may be electrically connected to a plurality of memory circuits 18. In the example shown in Figure 39, the AD conversion circuit 17a of pixel Pxa1 is electrically connected to the memory circuit 18a of pixel Pxa1 and also to the memory circuit 18b of pixel Pxb1.

[0233] By configuring the light detection device 1 in this way, the performance of the light detection device 1 can be improved. For example, the first pixel signal with a number of bits converted by the AD conversion circuit 17a can be stored in the storage circuit 18a, and the second pixel signal with a number of bits converted by the AD conversion circuit 17a can be stored in the storage circuit 18b. As a result of the AD conversion, it becomes possible to acquire multiple pixel signals with different numbers of bits.

[0234] (Modification 9) Figure 40 is a diagram illustrating an example of the configuration of a light detection device according to Modification 9. In the light detection device 1, one AD conversion circuit 17 and multiple memory circuits 18 may be provided for each of the multiple pixels P. In the example shown in Figure 40, an AD conversion circuit 17 (AD conversion circuit 17a1) is provided for pixels Pxa1 and Pxb1, and an AD conversion circuit 17 (AD conversion circuit 17a2) is provided for pixels Pxa2 and Pxb2.

[0235] The AD conversion circuit 17a1 is electrically connected to the memory circuit 18a of pixel Pxa1 and also to the memory circuit 18b of pixel Pxb1. Similarly, the AD conversion circuit 17a2 is electrically connected to the memory circuit 18a of pixel Pxa2 and also to the memory circuit 18b of pixel Pxb2. According to this modified photodetector, it is possible to improve the performance of the photodetector 1, for example, by improving the dynamic range.

[0236] (Modification 10) Figure 41 is a diagram illustrating an example of the configuration of a photodetector according to Modification 10. The photodetector 1 has pixels P as imaging pixels and pixels Pz as phase difference pixels. Each of pixels P and Pz may have a light-receiving element 10 (for example, a photodiode (PD)) and a readout circuit 15. For example, a part of the readout circuit 15 for pixel P and a part of the readout circuit 15 (readout circuit 15z) for pixel Pz are arranged to be swapped.

[0237] Of the readout circuit 15 for pixel P, transistors RST and AMP are provided in the element region 90 of pixel P. Also, of the readout circuit 15 for pixel P, transistor SEL is provided in the element region 90 (element region 90z) of pixel Pz, for example, as shown in the example in Figure 41.

[0238] In the readout circuit 15z for pixel Pz, transistors RST (transistor RSTz) and AMP (transistor AMPz) are provided in the element region 90z of pixel Pz. In addition, in the readout circuit 15z for pixel Pz, transistor SEL (transistor SELz) is provided in the element region 90 of pixel P.

[0239] Figure 42 is a diagram illustrating another configuration example of the photodetector according to Modification 10. The photodetector 1 may have a pixel P (pixel PA in Figure 42) having a light-receiving element 10 and a pixel circuit 20, and a pixel P (pixel PB in Figure 42) having a light-receiving element 10 and a readout circuit 15. For example, the light-receiving element 10 of pixel PA is made of a photodiode (PD), and the light-receiving element 10 of pixel PB is made of a SPAD.

[0240] In the pixel section 100, for example, multiple pixels PA and multiple pixels PB are arranged. Also, as shown in the example in Figure 42, a part of the pixel circuit 20 of pixel PA, for example, the output circuit 60, and a part of the readout circuit 15 of pixel PB, for example, the transistor SEL, are arranged to be swapped. In this modified case as well, the same effects as the embodiment and modified case described above can be obtained.

[0241] <3. Examples of Use> The above-described light detection device 1 can be used in various cases for sensing light such as visible light, infrared light, ultraviolet light, and X-rays, for example, as follows. - Devices that capture images for viewing purposes, such as digital cameras and portable devices with camera functions. - Devices used for traffic purposes, such as in-vehicle sensors that capture images of the front, rear, surroundings, and interior of a vehicle for safe driving such as automatic stopping and recognition of the driver's condition, surveillance cameras that monitor moving vehicles and roads, and distance measuring sensors that measure distances between vehicles. - Devices used in televisions and home appliances such as refrigerators and air conditioners that capture user gestures and allow device operation according to those gestures. - Devices used for medical and healthcare purposes, such as endoscopes and devices that perform angiography using infrared light reception. - Devices used for security purposes, such as surveillance cameras for crime prevention and cameras for person recognition. - Devices used for beauty purposes, such as skin measuring devices that capture images of the skin and microscopes that capture images of the scalp. - Devices used for sports purposes, such as action cameras and wearable cameras for sports use. - Devices used for agriculture, such as cameras that monitor the condition of fields and crops.

[0242] <4. Application Examples> (Application Examples to Mobile Devices) The technology relating to this disclosure (this technology) can be applied to various products. For example, the technology relating to this disclosure may be implemented as a device mounted on any type of mobile device such as automobiles, electric vehicles, hybrid electric vehicles, motorcycles, bicycles, personal mobility devices, airplanes, drones, ships, and robots.

[0243] Figure 43 is a block diagram showing a schematic configuration example of a vehicle control system, which is an example of a mobile control system to which the technology described herein may be applied.

[0244] The vehicle control system 12000 comprises a plurality of electronic control units connected via a communication network 12001. In the example shown in Figure 43, the vehicle control system 12000 includes a drive system control unit 12010, a body system control unit 12020, an external information detection unit 12030, an internal information detection unit 12040, and an integrated control unit 12050. The functional configuration of the integrated control unit 12050 is shown in the figure, which includes a microcomputer 12051, an audio / image output unit 12052, and an in-vehicle network interface 12053.

[0245] The drivetrain control unit 12010 controls the operation of devices related to the vehicle's drivetrain according to various programs. For example, the drivetrain control unit 12010 functions as a control device for a drivetrain generating device that generates driving force for the vehicle, such as an internal combustion engine or a drive motor; a drivetrain transmission mechanism that transmits driving force to the wheels; a steering mechanism that adjusts the steering angle of the vehicle; and a braking device that generates braking force for the vehicle.

[0246] The body system control unit 12020 controls the operation of various devices mounted on the vehicle body according to various programs. For example, the body system control unit 12020 functions as a control device for a keyless entry system, a smart key system, a power window system, or various lamps such as headlights, reverse lights, brake lights, turn signals, or fog lights. In this case, the body system control unit 12020 may receive radio waves transmitted from a portable device that replaces a key or signals from various switches. The body system control unit 12020 receives these radio waves or signals and controls the vehicle's door lock system, power window system, lamps, etc.

[0247] The external information detection unit 12030 detects information from outside the vehicle equipped with the vehicle control system 12000. For example, an imaging unit 12031 is connected to the external information detection unit 12030. The external information detection unit 12030 causes the imaging unit 12031 to capture images of the outside of the vehicle and receives the captured images. Based on the received images, the external information detection unit 12030 may perform object detection processing such as detecting people, cars, obstacles, signs, or characters on the road surface, or distance detection processing.

[0248] The imaging unit 12031 is a light sensor that receives light and outputs an electrical signal corresponding to the amount of light received. The imaging unit 12031 can output the electrical signal as an image or as distance measurement information. The light received by the imaging unit 12031 may be visible light or invisible light such as infrared light.

[0249] The in-vehicle information detection unit 12040 detects information inside the vehicle. The in-vehicle information detection unit 12040 is connected to, for example, a driver status detection unit 12041 that detects the driver's state. The driver status detection unit 12041 includes, for example, a camera that captures images of the driver, and the in-vehicle information detection unit 12040 may calculate the driver's level of fatigue or concentration, or determine whether the driver is drowsy, based on the detection information input from the driver status detection unit 12041.

[0250] The microcomputer 12051 can calculate control target values ​​for the drive force generator, steering mechanism, or braking device based on information inside and outside the vehicle acquired by the external information detection unit 12030 or the internal information detection unit 12040, and output control commands to the drive system control unit 12010. For example, the microcomputer 12051 can perform cooperative control aimed at realizing ADAS (Advanced Driver Assistance System) functions, including vehicle collision avoidance or impact mitigation, following driving based on distance between vehicles, maintaining vehicle speed, vehicle collision warning, or vehicle lane departure warning.

[0251] Furthermore, the microcomputer 12051 can perform cooperative control for purposes such as autonomous driving, where the vehicle drives autonomously without driver intervention, by controlling the drive force generating device, steering mechanism, or braking device, etc., based on information about the vehicle's surroundings acquired by the external information detection unit 12030 or the internal information detection unit 12040.

[0252] Furthermore, the microcomputer 12051 can output control commands to the body system control unit 12020 based on external information acquired by the external information detection unit 12030. For example, the microcomputer 12051 can control the headlights according to the position of a preceding or oncoming vehicle detected by the external information detection unit 12030, and perform coordinated control aimed at reducing glare, such as switching from high beams to low beams.

[0253] The audio-image output unit 12052 transmits at least one of audio and image output signals to an output device capable of visually or audibly notifying information to the vehicle's occupants or to those outside the vehicle. In the example shown in Figure 43, the output devices include an audio speaker 12061, a display unit 12062, and an instrument panel 12063. The display unit 12062 may include, for example, at least one of an onboard display and a head-up display.

[0254] Figure 44 shows an example of the installation position of the imaging unit 12031.

[0255] In Figure 44, the vehicle 12100 has imaging units 12101, 12102, 12103, 12104, and 12105 as the imaging unit 12031.

[0256] The imaging units 12101, 12102, 12103, 12104, and 12105 are installed, for example, on the front nose, side mirrors, rear bumper, back door, and the upper part of the windshield inside the vehicle 12100. The imaging unit 12101 installed on the front nose and the imaging unit 12105 installed on the upper part of the windshield inside the vehicle mainly acquire images of the front of the vehicle 12100. The imaging units 12102 and 12103 installed on the side mirrors mainly acquire images of the sides of the vehicle 12100. The imaging unit 12104 installed on the rear bumper or back door mainly acquires images of the rear of the vehicle 12100. The forward images acquired by imaging units 12101 and 12105 are mainly used for detecting preceding vehicles, pedestrians, obstacles, traffic lights, traffic signs, or lanes.

[0257] Figure 44 shows an example of the imaging ranges of imaging units 12101 to 12104. Imaging range 12111 indicates the imaging range of imaging unit 12101 located on the front nose, imaging ranges 12112 and 12113 indicate the imaging ranges of imaging units 12102 and 12103 located on the side mirrors, respectively, and imaging range 12114 indicates the imaging range of imaging unit 12104 located on the rear bumper or back door. For example, by superimposing the image data captured by imaging units 12101 to 12104, an overhead view image of the vehicle 12100 can be obtained.

[0258] At least one of the imaging units 12101 to 12104 may have a function for acquiring distance information. For example, at least one of the imaging units 12101 to 12104 may be a stereo camera consisting of multiple image sensors, or an image sensor having pixels for phase difference detection.

[0259] For example, the microcomputer 12051, based on distance information obtained from the imaging units 12101 to 12104, can determine the distance to each object within the imaging range 12111 to 12114 and the temporal change of this distance (relative speed to the vehicle 12100). In particular, it can extract the closest object on the vehicle 12100's path that is traveling in approximately the same direction as the vehicle 12100 at a predetermined speed (e.g., 0 km / h or more) as the preceding vehicle. Furthermore, the microcomputer 12051 can set a predetermined distance to be maintained before the preceding vehicle and perform automatic braking control (including follow-and-stop control) and automatic acceleration control (including follow-and-start control), etc. In this way, cooperative control aimed at autonomous driving, etc., that drives autonomously without driver operation, can be performed.

[0260] For example, the microcomputer 12051 can use distance information obtained from imaging units 12101 to 12104 to classify and extract three-dimensional object data related to three-dimensional objects, such as motorcycles, passenger cars, large vehicles, pedestrians, utility poles, and other three-dimensional objects, and use this data for automatic obstacle avoidance. For example, the microcomputer 12051 identifies obstacles around the vehicle 12100 into obstacles that are visible to the driver of the vehicle 12100 and obstacles that are difficult to see. The microcomputer 12051 then determines the collision risk, which indicates the degree of risk of collision with each obstacle. If the collision risk is above a set value and there is a possibility of collision, the microcomputer 12051 can provide driving assistance to avoid collisions by outputting a warning to the driver via the audio speaker 12061 or the display unit 12062, or by performing forced deceleration or evasive steering via the drive system control unit 12010.

[0261] At least one of the imaging units 12101 to 12104 may be an infrared camera that detects infrared light. For example, the microcomputer 12051 can recognize pedestrians by determining whether or not pedestrians are present in the images captured by the imaging units 12101 to 12104. Such pedestrian recognition is performed, for example, by a procedure to extract feature points from the images captured by the imaging units 12101 to 12104 as infrared cameras, and a procedure to perform pattern matching on a series of feature points that indicate the contour of an object to determine whether or not it is a pedestrian. When the microcomputer 12051 determines that a pedestrian is present in the images captured by the imaging units 12101 to 12104 and recognizes a pedestrian, the audio-image output unit 12052 controls the display unit 12062 to superimpose a rectangular contour line for emphasis on the recognized pedestrian. The audio-image output unit 12052 may also control the display unit 12062 to display an icon indicating a pedestrian at a desired position.

[0262] The above describes an example of a mobile control system to which the technology described herein can be applied. The technology described herein can be applied to, for example, the imaging unit 12031 of the configuration described above. Specifically, for example, the light detection device 1 can be applied to the imaging unit 12031. By applying the technology described herein to the imaging unit 12031, the functionality can be enhanced, and high-precision control using captured images can be performed in the mobile control system.

[0263] Although the present disclosure has been described above with reference to embodiments, modifications, usage examples, and application examples, the present technology is not limited to the above embodiments, and various modifications are possible. For example, although the above-described modifications were described as modifications of the above embodiments, the configurations of each modification can be combined as appropriate.

[0264] An optical detection device according to one embodiment of the present disclosure comprises a first region corresponding to a first photodetector, a second region corresponding to a second photodetector, and a first pixel circuit capable of outputting a first digital signal based on a signal generated by the first photodetector. A portion of the first pixel circuit is provided in the first region. Another portion of the first pixel circuit is provided in the second region. This makes it possible to realize an optical detection device that can reduce the number of signal lines.

[0265] An optical detection device according to one embodiment of the present disclosure comprises a first region corresponding to a first photodetector, a second region corresponding to a second photodetector, a first AD conversion circuit capable of converting a signal based on the charge generated by the first photodetector into a first digital signal, and a first storage circuit capable of storing the first digital signal. The first AD conversion circuit is provided in the first region. The first storage circuit is provided in the second region. This makes it possible to realize an optical detection device that can reduce the number of signal lines.

[0266] The effects described herein are merely examples and are not limited to those described herein; other effects may also exist. Furthermore, this disclosure may take the following configurations: (1) A photodetector comprising a first region corresponding to a first photodetector, a second region corresponding to a second photodetector, and a first pixel circuit capable of outputting a first digital signal based on a signal generated by the first photodetector, wherein a part of the first pixel circuit is provided in the first region and another part of the first pixel circuit is provided in the second region. (2) The photodetector according to (1), further comprising a second pixel circuit capable of outputting a second digital signal based on a signal generated by the second photodetector, wherein a part of the second pixel circuit is provided in the second region and another part of the second pixel circuit is provided in the first region. (3) The photodetector according to (1) or (2), wherein the first photodetector is capable of receiving visible light and generating a signal, and the second photodetector is capable of receiving infrared light and generating a signal. (4) The photodetector according to any one of (1) to (3), wherein the first photodetector is capable of receiving light in a first wavelength range of visible light and generating a signal, and the second photodetector is capable of receiving light in a second wavelength range of visible light and generating a signal. (5) The photodetector according to any one of (1) to (4), wherein the first pixel circuit comprises a first detection circuit capable of generating a first signal based on the signal generated by the first photodetector, a first counter capable of counting the first signal, and a first output circuit capable of outputting the first digital signal based on the count value by the first counter. (6) The photodetector according to (5), wherein the first detection circuit is provided in the first region, and the first counter and the first output circuit are provided in the second region. (7) The photodetector according to (5) or (6), wherein the first detection circuit and the first counter are provided in the first region, and the first output circuit is provided in the second region.(8) The photodetector according to any one of (5) to (7), further comprising a second pixel circuit capable of outputting a second digital signal based on a signal generated by the second photodetector, wherein the second pixel circuit comprises a second detection circuit capable of generating a second signal based on a signal generated by the second photodetector, a second counter capable of counting the second signal, and a second output circuit capable of outputting the second digital signal based on a count value from the second counter. (9) The photodetector according to (8), wherein the first detection circuit, the second counter, and the second output circuit are provided in the first region, and the first counter, the first output circuit, and the second detection circuit are provided in the second region. (10) The photodetector according to (8) or (9), wherein the first detection circuit, the first counter, and the second output circuit are provided in the first region, and the first output circuit, the second detection circuit, and the second counter are provided in the second region. (11) The photodetector according to any one of (1) to (10), further comprising a third region corresponding to a third photodetector and a third pixel circuit capable of outputting a third digital signal based on a signal generated by the third photodetector, wherein the first pixel circuit has a first output circuit capable of outputting the first digital signal, the third pixel circuit has a third output circuit capable of outputting the third digital signal, the first output circuit is provided in the second region, the third output circuit is provided in the third region, and the first output circuit and the third output circuit are positioned to be aligned in a first direction. (12) The photodetector according to (11), further comprising signal lines extending in a first direction and electrically connected to the first output circuit and the third output circuit, wherein the first region and the second region are positioned adjacent to each other in a second direction different from the first direction, and the second region and the third region are positioned adjacent to each other in the first direction.(13) The light detection device according to any one of (1) to (12), further comprising a first layer having the first light-receiving element and the second light-receiving element, and a second layer stacked on the first layer, wherein the first light-receiving element is provided in the first region of the first layer, the second light-receiving element is provided in the second region of the first layer, a part of the first pixel circuit is provided in the first region of the second layer, and another part of the first pixel circuit is provided in the second region of the second layer. (14) The light detection device according to (13), further comprising a second pixel circuit capable of outputting a second digital signal based on a signal generated by the second light-receiving element, wherein a part of the second pixel circuit is provided in the second region of the second layer, and another part of the second pixel circuit is provided in the first region of the second layer. (15) The photodetector according to any one of (1) to (14), wherein the first photodetector is an avalanche diode, the first pixel circuit has a first supply circuit electrically connected between the first photodetector and a first potential line, and the first supply circuit is capable of supplying current to the first photodetector. (16) The photodetector comprising a first region corresponding to a first photodetector, a second region corresponding to a second photodetector, a first AD conversion circuit capable of converting a signal based on a charge generated by the first photodetector into a first digital signal, and a first storage circuit capable of storing the first digital signal, wherein the first AD conversion circuit is provided in the first region, and the first storage circuit is provided in the second region. (17) The photodetector according to (16), further comprising a second AD conversion circuit capable of converting a signal based on the charge generated by the second photodetector into a second digital signal, and a second storage circuit capable of storing the second digital signal, wherein the second AD conversion circuit is provided in the second region and the second storage circuit is provided in the first region.(18) The photodetector according to (17), wherein the first AD conversion circuit is capable of converting a signal based on the charge generated by the first photodetector into a first digital signal of a first number of bits, and the second AD conversion circuit is capable of converting a signal based on the charge generated by the second photodetector into a second digital signal of a second number of bits different from the first number of bits. (19) The photodetector according to any one of (16) to (18), further comprising: a second AD conversion circuit capable of converting a signal based on an charge generated by the second photodetector into a second digital signal; a second storage circuit capable of storing the second digital signal; a first layer having the first photodetector and the second photodetector; and a second layer stacked on the first layer, wherein the first photodetector is provided in the first region of the first layer, the second photodetector is provided in the second region of the first layer, the first AD conversion circuit and the second storage circuit are provided in the first region of the second layer, and the first storage circuit and the second AD conversion circuit are provided in the second region of the second layer. (20) A light detection system comprising a light source capable of irradiating light onto an object, and a light detection device for receiving light from the object, wherein the light detection device has a first region corresponding to a first light-receiving element, a second region corresponding to a second light-receiving element, and a first pixel circuit capable of outputting a first digital signal based on a signal generated by the first light-receiving element, wherein a part of the first pixel circuit is provided in the first region, and another part of the first pixel circuit is provided in the second region.

[0267] This application claims priority based on Japanese Patent Application No. 2025-025959, filed with the Japan Patent Office on 20 February 2025, and all contents of that application are incorporated herein by reference.

[0268] Those skilled in the art will understand that various modifications, combinations, subcombinations, and changes can be conceived depending on design requirements and other factors, and that these fall within the scope of the attached claims and their equivalents.

Claims

1. A light detection device comprising a first region corresponding to a first light-receiving element, a second region corresponding to a second light-receiving element, and a first pixel circuit capable of outputting a first digital signal based on a signal generated by the first light-receiving element, wherein a part of the first pixel circuit is provided in the first region, and another part of the first pixel circuit is provided in the second region.

2. The photodetector according to claim 1, further comprising a second pixel circuit capable of outputting a second digital signal based on a signal generated by the second photodetector, wherein a part of the second pixel circuit is provided in the second region and another part of the second pixel circuit is provided in the first region.

3. The photodetector according to claim 1, wherein the first photodetector is capable of receiving visible light and generating a signal, and the second photodetector is capable of receiving infrared light and generating a signal.

4. The photodetector according to claim 1, wherein the first photodetector is capable of receiving light in a first wavelength range of visible light and generating a signal, and the second photodetector is capable of receiving light in a second wavelength range of visible light and generating a signal.

5. The photodetector according to claim 1, wherein the first pixel circuit comprises a first detection circuit capable of generating a first signal based on a signal generated by the first photodetector, a first counter capable of counting the first signal, and a first output circuit capable of outputting a first digital signal based on a count value from the first counter.

6. The photodetector according to claim 5, wherein the first detection circuit is provided in the first region, and the first counter and the first output circuit are provided in the second region.

7. The photodetector according to claim 5, wherein the first detection circuit and the first counter are provided in the first region, and the first output circuit is provided in the second region.

8. The photodetector according to claim 5, further comprising a second pixel circuit capable of outputting a second digital signal based on a signal generated by the second photodetector, wherein the second pixel circuit comprises a second detection circuit capable of generating a second signal based on a signal generated by the second photodetector, a second counter capable of counting the second signal, and a second output circuit capable of outputting the second digital signal based on the count value by the second counter.

9. The photodetector according to claim 8, wherein the first detection circuit, the second counter, and the second output circuit are provided in the first region, and the first counter, the first output circuit, and the second detection circuit are provided in the second region.

10. The photodetector according to claim 8, wherein the first detection circuit, the first counter, and the second output circuit are provided in the first region, and the first output circuit, the second detection circuit, and the second counter are provided in the second region.

11. The photodetector according to claim 1, further comprising a third region corresponding to a third photodetector and a third pixel circuit capable of outputting a third digital signal based on a signal generated by the third photodetector, wherein the first pixel circuit has a first output circuit capable of outputting the first digital signal, the third pixel circuit has a third output circuit capable of outputting the third digital signal, the first output circuit is provided in the second region, the third output circuit is provided in the third region, and the first output circuit and the third output circuit are positioned to be aligned in a first direction.

12. The photodetector according to claim 11, further comprising signal lines extending in the first direction and electrically connected to the first output circuit and the third output circuit, wherein the first region and the second region are adjacent to each other in a second direction different from the first direction, and the second region and the third region are adjacent to each other in the first direction.

13. The photodetector according to claim 1, comprising a first layer having a first photodetector and a second photodetector, and a second layer stacked on the first layer, wherein the first photodetector is provided in a first region of the first layer, the second photodetector is provided in a second region of the first layer, a part of the first pixel circuit is provided in the first region of the second layer, and another part of the first pixel circuit is provided in the second region of the second layer.

14. The photodetector according to claim 13, further comprising a second pixel circuit capable of outputting a second digital signal based on a signal generated by the second photodetector, wherein a part of the second pixel circuit is provided in the second region of the second layer, and the other part of the second pixel circuit is provided in the first region of the second layer.

15. The photodetector according to claim 1, wherein the first photodetector is an avalanche diode, the first pixel circuit has a first supply circuit electrically connected between the first photodetector and a first potential line, and the first supply circuit is capable of supplying current to the first photodetector.

16. A photodetector comprising: a first region corresponding to a first photodetector; a second region corresponding to a second photodetector; a first AD conversion circuit capable of converting a signal based on the charge generated by the first photodetector into a first digital signal; and a first storage circuit capable of storing the first digital signal, wherein the first AD conversion circuit is provided in the first region and the first storage circuit is provided in the second region.

17. The photodetector according to claim 16, further comprising a second AD conversion circuit capable of converting a signal based on the charge generated by the second photodetector into a second digital signal, and a second storage circuit capable of storing the second digital signal, wherein the second AD conversion circuit is provided in the second region and the second storage circuit is provided in the first region.

18. The photodetector according to claim 17, wherein the first AD conversion circuit is capable of converting a signal based on the charge generated by the first photodetector into a first digital signal with a first number of bits, and the second AD conversion circuit is capable of converting a signal based on the charge generated by the second photodetector into a second digital signal with a second number of bits different from the first number of bits.

19. The photodetector according to claim 16, further comprising: a second AD conversion circuit capable of converting a signal based on a charge generated by the second photodetector into a second digital signal; a second storage circuit capable of storing the second digital signal; a first layer having the first photodetector and the second photodetector; and a second layer stacked on the first layer, wherein the first photodetector is provided in the first region of the first layer, the second photodetector is provided in the second region of the first layer, the first AD conversion circuit and the second storage circuit are provided in the first region of the second layer, and the first storage circuit and the second AD conversion circuit are provided in the second region of the second layer.

20. A light detection system comprising a light source capable of irradiating light onto an object, and a light detection device for receiving light from the object, wherein the light detection device has a first region corresponding to a first light-receiving element, a second region corresponding to a second light-receiving element, and a first pixel circuit capable of outputting a first digital signal based on a signal generated by the first light-receiving element, wherein a part of the first pixel circuit is provided in the first region, and another part of the first pixel circuit is provided in the second region.

Images