Solid-state imaging element and imaging device

Abstract

The object of the present invention is to improve the signal quality of a solid-state imaging element for detecting address events. In the solid-state imaging element, an opening pixel and a light-shielding pixel are arranged. In the solid-state imaging element, the opening pixels respectively detect whether the amount of change in the amount of incident light exceeds a predetermined threshold value, and output a detection signal representing the detection result. On the other hand, in the solid-state imaging element, the light-shielding pixels respectively output correction signals based on the amount of noise generated in the opening pixels, and the opening pixels are respectively constructed to detect whether the amount of change in the amount of incident light exceeds a predetermined threshold value, and output a detection signal representing the detection result.

Description

Technical Field

[0001] The present technology relates to a solid-state imaging element and an imaging device. Specifically, the present technology relates to a solid-state imaging element and an imaging device that compare the amount of incident light with a threshold value. Background Art

[0002] Hitherto, synchronous solid-state imaging elements constructed to acquire image data (frames) synchronously with a synchronization signal such as a vertical synchronization signal have been used in imaging devices and the like. Such ordinary synchronous solid-state imaging elements can acquire image data only at intervals of the synchronization signal (for example, every 1 / 60 second). Therefore, it is difficult to react in situations where faster processing is required in fields related to transportation and robots, etc. For this reason, an asynchronous solid-state imaging element has been proposed, which includes a detection circuit in each pixel, and the detection circuit is constructed to detect the fact that the amount of change in the amount of light in each pixel as an address event exceeds a threshold in real time for each pixel address (for example, see patent document 1). A solid-state imaging element for detecting address events in each pixel in this manner is called a dynamic vision sensor (DVS: Dynamic Vision Sensor).

[0003] [Citation List]

[0004] [Patent Document]

[0005] [Patent Document 1]

[0006] JP-T-2017-535999 Summary of the invention

[0007] [Technical issues]

[0008] The asynchronous solid-state imaging element (i.e., DVS) as described above generates and outputs data at a much higher speed than the synchronous solid-state imaging element. Therefore, for example, in the field of transportation, the processing of identifying people or objects by image recognition is performed at high speed. However, in a pixel, even if no light is received, the photodiode sometimes outputs a current called "dark current", and this dark current causes dark current noise. In addition, in the pixel, in the circuit in the subsequent stage of the photodiode, due to the difference in characteristics of transistors such as differential pairs, a constant offset voltage is sometimes generated, and this offset voltage causes offset noise. The above-mentioned solid-state imaging element has the problem that the signal quality of the signal generated by the pixel is reduced due to these dark current noises and offset noises.

[0009] The present technology has been made in view of the above-described circumstances, and an object of the present technology is to improve the signal quality of a solid-state imaging element for detecting an address event.

[0010] [Technical solution to the problem]

[0011] The present technology is made to solve the above-mentioned problems, and according to a first aspect of the present technology, there is provided a solid-state imaging element, which includes: opening pixels, each configured to detect whether the amount of change in the amount of incident light exceeds a predetermined threshold value, and output a detection signal indicating the detection result; and light-shielding pixels, each configured to output a correction signal based on the amount of noise generated in the opening pixels. This provides the following effect: namely, a correction signal is generated based on the amount of noise generated in the opening pixels.

[0012] Furthermore, in the first aspect, the opening pixels and the light-shielding pixels may be arranged on a predetermined plane. This provides an effect that a correction signal is generated by the light-shielding pixels located on the same plane as the opening pixels.

[0013] Furthermore, in the first aspect, the opening pixels may be arranged on one of a pair of planes facing each other, and the light shielding pixels may be arranged on the other of the pair of planes. This provides an effect of increasing the area of ​​the region where the opening pixels are arranged.

[0014] Furthermore, in the first aspect, the light shielding pixels and the opening pixels may be arranged one to one. This provides an effect that a correction signal is generated for each opening pixel.

[0015] Furthermore, in the first aspect, a plurality of light-shielding pixel blocks may be arranged on the other plane of the pair of planes, each light-shielding pixel block includes a predetermined number of light-shielding pixels, and the plurality of light-shielding pixel blocks may be arranged at intervals from each other. This provides the effect of generating a correction signal for each light-shielding pixel block.

[0016] Furthermore, in the first aspect, the light-shielding pixels may be arranged irregularly. This provides an effect that a correction signal is generated by the light-shielding pixels arranged irregularly.

[0017] In addition, in the first aspect, the solid-state imaging element may further include a signal processing unit configured to perform a correction process for removing the noise from the pixel signal based on the light amount according to the correction signal, wherein the opening pixels may further output the pixel signals respectively. This provides the following effect: namely, noise is removed from the pixel signal.

[0018] Furthermore, in the first aspect, the light-shielded pixels may each include: a photoelectric conversion element; a current-voltage conversion unit configured to convert a dark current generated in the photoelectric conversion element into a voltage signal; a quantizer configured to detect whether the amount of change in the voltage signal exceeds the threshold value; and a pixel signal generation unit configured to generate a pixel signal as the correction signal based on the light amount. This provides the effect that the detection signal and the pixel signal are generated by the light-shielded pixel.

[0019] Furthermore, in the first aspect, the current-voltage conversion section may convert the dark current into the voltage signal through a multi-stage loop circuit. This provides an effect of increasing conversion gain.

[0020] Furthermore, in the first aspect, the photoelectric conversion element and a part of the pixel signal generating section may be provided on a predetermined light receiving chip, and the remaining part of the pixel signal generating section, the current-voltage conversion section and the quantizer may be provided on a predetermined circuit chip. This provides the effect that the circuit scale of the circuit chip is reduced.

[0021] Furthermore, in the first aspect, the photoelectric conversion element, a part of the pixel signal generating section, and a part of the current-voltage conversion section may be provided on a predetermined light receiving chip, and the rest of the pixel signal generating section, the rest of the current-voltage conversion section, and the quantizer may be provided on a predetermined circuit chip. This provides the effect that the circuit scale of the circuit chip is reduced.

[0022] Furthermore, in the first aspect, the photoelectric conversion element, a part of the current-voltage conversion section, and the pixel signal generation section may be provided on a predetermined light receiving chip, and the remaining part of the current-voltage conversion section and the quantizer may be provided on a predetermined circuit chip. This provides the effect that the circuit scale of the circuit chip is reduced.

[0023] In addition, in the first aspect, the light shielding pixels may further include selectors respectively configured to select a predetermined test signal or the voltage signal and output the selected signal as a selection signal, and the quantizer detects whether the variation of the selection signal exceeds the threshold value. This provides the effect that the pixel signal is output regardless of whether an address event exists.

[0024] In addition, in this first aspect, the opening pixels may respectively include: a photoelectric conversion element configured to generate a photocurrent by photoelectric conversion; a current-voltage conversion unit configured to convert the difference between the photocurrent and the dark current into a voltage signal; and a quantizer configured to detect whether the amount of change in the voltage signal exceeds the threshold. The light-shielded pixels may respectively output the dark current as the correction signal. This provides the following effect: namely, dark current noise is prevented.

[0025] Furthermore, in the first aspect, the solid-state image pickup element may further include a threshold value adjustment section configured to adjust the threshold value based on the correction signal. This provides an effect of improving the detection accuracy of address events.

[0026] In addition, according to a second aspect of the present technology, there is provided an image pickup device, comprising: opening pixels, each configured to detect whether the amount of change in the amount of incident light exceeds a predetermined threshold value, and displaying the detection result; light shielding pixels, each configured to output a correction signal based on the amount of noise generated in the opening pixels; and a signal processing unit configured to process the detection signal. This provides the following effect: that is, a correction signal for correcting the noise generated in the opening pixels is generated, and the detection signal is processed. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 : is a block diagram showing a configuration example of an image pickup device according to a first embodiment of the present technology.

[0028] Figure 2 : is a diagram showing an example of a stacked structure of a solid-state imaging element according to the first embodiment of the present technology.

[0029] Figure 3 : is a block diagram showing a configuration example of a solid-state image pickup element according to a first embodiment of the present technology.

[0030] Figure 4 is a block diagram showing a configuration example of a pixel array section according to a first embodiment of the present technology.

[0031] Figure 5 : is a block diagram showing a configuration example of an open pixel block according to the first embodiment of the present technology.

[0032] Figure 6 : is a circuit diagram showing a configuration example of a pixel signal generating section and a light shielding section according to the first embodiment of the present technology.

[0033] Figure 7 is an example of a cross-sectional view of the solid-state imaging element according to the first embodiment of the present technology.

[0034] Figure 8: is a block diagram showing a configuration example of an address event detection section according to the first embodiment of the present technology.

[0035] Fig. 9 : is a circuit diagram showing a configuration example of a current-voltage conversion section according to a first embodiment of the present technology.

[0036] Fig.10 : is a circuit diagram showing a configuration example of a subtractor and a quantizer according to the first embodiment of the present technology.

[0037] Fig.11 is a block diagram showing a configuration example of a column ADC according to the first embodiment of the present technology.

[0038] Fig.12 is a timing chart showing an example of the operation of the solid-state image pickup element according to the first embodiment of the present technology.

[0039] Fig.13 : is a block diagram showing a configuration example of a signal processing section according to the first embodiment of the present technology.

[0040] Fig.14 is a flowchart illustrating an example of the operation of the solid-state image pickup element according to the first embodiment of the present technology.

[0041] Fig.15 : is a circuit diagram showing a configuration example of a light-shielding pixel block according to a first modification example of the first embodiment of the present technology.

[0042] Fig.16 : is a circuit diagram showing a configuration example of a light-shielding pixel block according to a second modification example of the first embodiment of the present technology.

[0043] Fig.17 : is a circuit diagram showing a configuration example of a light-shielding pixel block according to a third modification example of the first embodiment of the present technology.

[0044] Fig.18 : is a block diagram showing a configuration example of an address event detection section according to a fourth modification example of the first embodiment of the present technology.

[0045] Fig.19 : is a circuit diagram showing a configuration example of a pixel signal generating section and a light shielding section according to a second embodiment of the present technology.

[0046] Fig. 20 : is a circuit diagram showing a configuration example of a current-voltage conversion section according to a second embodiment of the present technology.

[0047] Fig.21 is an example of a cross-sectional view of a solid-state imaging element according to a third embodiment of the present technology.

[0048] Fig. 22 An example of a plan view of a light receiving chip and a circuit chip according to a third embodiment of the present technology is shown.

[0049] Fig.23 An example of a plan view of a circuit chip according to a third embodiment of the present technology is shown.

[0050] Fig.24 : is a block diagram showing a configuration example of an opening pixel and a light shielding pixel according to a third embodiment of the present technology.

[0051] Fig.25 is a circuit diagram showing a configuration example of a current-voltage conversion section according to a third embodiment of the present technology.

[0052] Fig.26 : is a block diagram showing a configuration example of a solid-state image pickup element according to a fourth embodiment of the present technology.

[0053] Fig. 27 is a block diagram showing a configuration example of a signal processing section according to a fourth embodiment of the present technology.

[0054] Fig.28 is a block diagram showing an example of the configuration of an image pickup device according to a fifth embodiment of the present technology.

[0055] Fig.29 is a block diagram showing an example of a schematic configuration of a vehicle control system.

[0056] Fig.30 It is a diagram for assisting in explaining an example of the installation positions of the vehicle exterior information detection unit and the imaging unit. DETAILED DESCRIPTION

[0057] Now, a mode for implementing the present technology (hereinafter referred to as an embodiment) will be described. The following items will be described in order.

[0058] 1. First Embodiment (Example in which Light-Shielding Pixels and Opening Pixels are Arranged on the Same Plane)

[0059] 2. Second Embodiment (Example in which light-shielding pixels and opening pixels are arranged and a two-stage circuit is provided)

[0060] 3. Third Embodiment (Example in which Light-Shielding Pixels and Opening Pixels are Arranged on Different Planes)

[0061] 4. Fourth Embodiment (Example in which light-shielding pixels and opening pixels are arranged and threshold values ​​are adjusted)

[0062] 5. Fifth Embodiment (Scanning Method)

[0063] 6. Application examples for mobile objects

[0064] <1. First Embodiment>

[0065] [Configuration Example of Image Capture Device]

[0066] Figure 1 1 is a block diagram showing a configuration example of an imaging device 100 according to a first embodiment of the present technology. The imaging device 100 includes an imaging lens 110, a solid-state imaging element 200, a recording section 120, and a control section 130. As the imaging device 100, a camera mounted on an industrial robot or a vehicle-mounted camera is assumed.

[0067] The imaging lens 110 collects incident light and guides the incident light to the solid-state imaging element 200. The solid-state imaging element 200 performs photoelectric conversion on the incident light and acquires image data. The solid-state imaging element 200 performs predetermined signal processing (e.g., image recognition processing) on ​​the acquired image data, and outputs data indicating the processing result and the address event detection signal to the recording section 120 through the signal line 209. The detection signal generation method will be described later.

[0068] The recording section 120 records data from the solid-state imaging element 200. The control section 130 controls the solid-state imaging element 200 to acquire image data.

[0069] [Configuration Example of Solid-State Image Pickup Element]

[0070] Figure 2 1 is a diagram showing an example of a stacked structure of a solid-state imaging element 200 according to the first embodiment of the present technology. The solid-state imaging element 200 includes a circuit chip 202 and a light receiving chip 201 stacked on the circuit chip 202. These chips are electrically connected to each other through a connection portion such as a through hole. Note that the above chips can also be connected to each other by Cu-Cu connection or bumps instead of through holes.

[0071] Figure 3 2 is a block diagram showing a configuration example of a solid-state imaging element 200 according to the first embodiment of the present technology. The solid-state imaging element 200 includes a drive circuit 211 , a signal processing section 220 , an arbitrator 213 , a column ADC 230 , and a pixel array section 300 .

[0072] In the pixel array section 300, a plurality of pixels are arranged in a two-dimensional lattice pattern. In addition, the pixel array section 300 is divided into a plurality of pixel blocks, each of which includes a predetermined number of pixels. Hereinafter, a set of pixels or pixel blocks arranged in the horizontal direction is referred to as a "row", and a set of pixels or pixel blocks arranged in a direction perpendicular to the row is referred to as a "column".

[0073] Each pixel generates an analog signal having a voltage based on the photocurrent as a pixel signal. In addition, each pixel block detects the presence or absence of an address event based on whether the amount of change in the photocurrent exceeds a predetermined threshold. Then, the pixel block where the address event occurs outputs a request to the arbitrator.

[0074] The driving circuit 211 drives each pixel so that each pixel outputs a pixel signal to the column ADC 230 .

[0075] The arbitrator 213 arbitrates between requests from the respective pixel blocks, and sends a response to the pixel block based on the arbitration result. The pixel block that has received the response supplies a detection signal indicating the detection result to the drive circuit 211 and the signal processing section 220.

[0076] The column ADC 230 converts the analog pixel signal of each column from each pixel block into a digital signal, and supplies the digital signal to the signal processing section 220 .

[0077] The signal processing unit 220 performs predetermined signal processing such as CDS (Correlated Double Sampling) processing, noise correction processing, or image recognition processing on the digital signal from the column ADC 230 , and provides data indicating the processing result and a detection signal to the recording unit 120 via a signal line 209 .

[0078] In addition, the driving circuit 211 and the signal processing section 220 receive a mode signal MODE generated by the control section 130. The mode signal MODE is a signal for setting any mode among a plurality of modes including a calibration mode and an imaging mode. Here, the calibration mode is a mode for obtaining a correction value for correcting dark current noise and offset noise. On the other hand, the imaging mode is a mode for acquiring image data. The calibration mode is executed when a predetermined event occurs (for example, when the imaging device 100 is powered on), or, for example, at regular intervals.

[0079] [Configuration Example of Pixel Array Section]

[0080] Figure 4 1 is a block diagram showing a configuration example of the pixel array section 300 according to the first embodiment of the present technology. The pixel array section 300 has an opening region exposed to light and a light shielding region not exposed to light on its light receiving surface. Figure 4 The shaded portion in represents a light shielding area. The light shielding area is, for example, provided around the opening area. In addition, a predetermined direction parallel to the light receiving surface of the pixel array unit 300 is an X direction, and a direction perpendicular to the light receiving surface is a Z direction. A direction perpendicular to the X direction and the Z direction is a Y direction.

[0081] The light shielding area and the opening area are divided into a plurality of pixel blocks. Each pixel block in the light shielding area is a light shielding pixel block 310, and each pixel block in the opening area is an opening pixel block 340. In each light shielding pixel block 310, a plurality of light shielding pixels are arranged in I rows × J columns (I and J are integers). In addition, in each opening pixel block 340, a plurality of opening pixels are arranged in I rows × J columns.

[0082] The light shielding pixel block 310 includes a pixel signal generating section 320, a plurality of light shielding sections 330 of I rows×J columns, and an address event detecting section 400. The plurality of light shielding sections 330 in the light shielding pixel block 310 share the pixel signal generating section 320 and the address event detecting section 400. In addition, a circuit including the light shielding section 330, the pixel signal generating section 320, and the address event detecting section 400 at certain coordinates serves as a light shielding pixel at the coordinates in question. In addition, a vertical signal line VSL is arranged in each column of the light shielding pixel block 310.

[0083] The light shielding section 330 outputs the dark current generated in the photoelectric conversion element thereof and supplies the dark current to the pixel signal generating section 320 or the address event detecting section 400 under the control of the driving circuit 211 .

[0084] The pixel signal generating section 320 generates a signal having a voltage based on the dark current as the pixel signal SIG. The pixel signal generating section 320 supplies the generated pixel signal SIG to the column ADC 230 through the vertical signal line VSL.

[0085] The address event detection unit 400 detects the presence or absence of an address event based on whether the change amount of the dark current from each light shielding unit 330 exceeds a predetermined threshold. Examples of address events include an on event indicating that the change amount exceeds an upper threshold and an off event indicating that the change amount drops below a lower threshold. In addition, examples of the address event detection signal include 1 bit indicating the result of the on event detection and 1 bit indicating the result of the off event detection. Note that the address event detection unit 400 is also capable of detecting only the on event.

[0086] When an address event occurs, the address event detection section 400 provides a request for requesting the transmission of a detection signal to the arbitrator 213. Then, when the address event detection section 400 receives a response to the request from the arbitrator 213, the address event detection section 400 provides a detection signal to the drive circuit 211 and the signal processing section 220.

[0087] Figure 5: is a block diagram showing an example of the construction of an opening pixel block 340 according to the first embodiment of the present technology. The opening pixel block 340 includes a pixel signal generating section 341, a plurality of light receiving sections 342 of I rows×J columns, and an address event detecting section 343. The plurality of light receiving sections 342 in the opening pixel block 340 share the pixel signal generating section 341 and the address event detecting section 343. In addition, a circuit including a light receiving section 342, a pixel signal generating section 341, and an address event detecting section 343 at certain coordinates is used as an opening pixel at the coordinates in question. In addition, a vertical signal line VSL is arranged in each column of the opening pixel block 340.

[0088] The light receiving section 342 generates a photocurrent by photoelectric conversion, and outputs the photocurrent. The pixel signal generating section 341 and the address event detecting section 343 are configured similarly to the corresponding circuits in the light shielding pixel block 310.

[0089] [Configuration Example of Light-Shielding Pixel Block]

[0090] Figure 6 1 is a circuit diagram showing a configuration example of a light shielding pixel block 310 according to a first embodiment of the present technology. In the light shielding pixel block 310, a pixel signal generating section 320 includes a reset transistor 321, an amplifying transistor 322, a selecting transistor 323, and a floating diffusion layer 324. A plurality of light shielding sections 330 are commonly connected to an address event detecting section 400 through a predetermined connection point.

[0091] In addition, the light shielding portion 330 includes a transfer transistor 331, an overflow gate (OFG: OverFlowGate) transistor 332, and a photoelectric conversion element 333. When the number of pixels in the light shielding pixel block 310 is N (N is an integer), the number of each of the transfer transistor 331, the OFG transistor 332, and the photoelectric conversion element 333 is N. The nth (n is an integer from 1 to N) transfer transistor 331 in the light shielding pixel block 310 receives a transfer signal TRGn provided from the drive circuit 211. The nth OFG transistor 332 receives a control signal OFGn provided from the drive circuit 211.

[0092] In addition, as the reset transistor 321 , the amplification transistor 322 , and the selection transistor 323 , for example, N-type MOS (Metal-Oxide-Semiconductor) transistors are used. Similarly, as the transfer transistor 331 and the OFG transistor 332 , N-type MOS transistors are used.

[0093] In addition, each photoelectric conversion element 333 is provided on the light receiving chip 201. All elements other than the photoelectric conversion element 333 are provided on the circuit chip 202.

[0094] The photoelectric conversion element 333 performs photoelectric conversion on incident light and generates charges. However, since the light shielding portion 330 is not exposed to light, dark current is generated in the photoelectric conversion element 333. According to the transfer signal TRGn, the transfer transistor 331 transfers the charges from the corresponding photoelectric conversion element 333 to the floating diffusion layer 324. According to the control signal OFGn, the OFG transistor 332 provides the dark current generated in the corresponding photoelectric conversion element 333 to the connection node.

[0095] The floating diffusion layer 324 accumulates charges and generates a voltage based on the amount of accumulated charges. The reset transistor 321 initializes the amount of charge in the floating diffusion layer 324 according to the reset signal RST from the drive circuit 211. The amplifier transistor 322 amplifies the voltage of the floating diffusion layer 324. The selection transistor 323 outputs a signal having an amplified voltage as a pixel signal SIG to the column ADC 230 through the vertical signal line VSL according to the selection signal SEL from the drive circuit 211.

[0096] Note that the circuit configuration of the open pixel block 340 is similar to Figure 6 The circuit structure of the light-shielding pixel block 310 is similar.

[0097] In the calibration mode, regardless of whether there is an address event in the light-shielded pixel block 310, the driving circuit 211 sequentially drives the light-shielded pixels using the transfer signal TRGn, so that the light-shielded pixels transfer charges to the floating diffusion layer 324. Thus, the respective pixel signals of the plurality of light-shielded pixels in the open pixel block 340 are sequentially output. The above-mentioned pixel signals are signals based on the dark current noise amount and the offset noise amount generated in the open pixels, and are used as correction signals for correcting noise.

[0098] On the other hand, in the imaging mode, the driving circuit 211 drives all the open pixels using the control signal OFGn so that the open pixels detect whether the change in the incident light amount exceeds a threshold value (ie, the presence or absence of an address event) in units of the open pixel block 340 .

[0099] Then, when an address event is detected in a certain open pixel block 340, the drive circuit 211 sequentially drives all the open pixels of the block in question so that the open pixels generate pixel signals based on the amount of light. Then, the signal processing section 220 performs correction processing for removing noise from the pixel signals of the open pixels based on the pixel signals (correction signals) of the light-shielded pixels.

[0100] In this manner, the solid-state imaging element 200 outputs only the pixel signals of the open pixel block 340 in which the address event is detected to the column ADC 230. In this way, compared with the case where the pixel signals of all open pixels are output regardless of the presence or absence of the address event, the power consumption of the solid-state imaging element 200 and the amount of image processing can be reduced.

[0101] Furthermore, the address event detection section 400 is shared by a plurality of opening pixels, so that the circuit scale of the solid-state imaging element 200 can be reduced compared to a case where the address event detection section 400 is provided for each opening pixel.

[0102] In addition, the signal processing unit 220 uses the pixel signal of the light-shielded pixel as a correction signal, thereby being able to remove dark current noise and offset noise generated in the open pixel.

[0103] Figure 7 is an example of a cross-sectional view of the solid-state imaging element 200 according to the first embodiment of the present technology. Figure 7 is along with Figure 4 A cross-sectional view taken along a plane perpendicular to the line segment X1 to X2. On the light receiving surface, light shielding pixels 360 and open pixels 370 are arranged.

[0104] An on-chip microlens 361 and a photoelectric conversion element 333 are provided in each light-shielding pixel 360. Furthermore, a light-shielding member 362 is provided between the on-chip microlens 361 and the photoelectric conversion element 333 in the light-shielding region.

[0105] Meanwhile, an on-chip microlens 371 and a photoelectric conversion element 372 are provided in each opening pixel 370 .

[0106] Note that although the photoelectric conversion element 333 is provided in the light-shielded pixel 360 , a constant current source for supplying a dark current generated in the photoelectric conversion element 372 in the open pixel 370 may be provided instead of the photoelectric conversion element 333 .

[0107] like Figure 7 As shown, both the light-shielding pixels 360 and the open pixels 370 are arranged on the light-receiving surface of the light-receiving chip 201 .

[0108] [Configuration Example of Address Event Detection Section]

[0109] Figure 8 4 is a block diagram showing a configuration example of the address event detection section 400 according to the first embodiment of the present technology. The address event detection section 400 includes a current-voltage conversion section 410 , a buffer 420 , a subtractor 430 , a quantizer 440 , and a transmission section 450 .

[0110] The current-voltage conversion section 410 converts the current signal from the corresponding light shielding section 330 into a voltage signal corresponding to the logarithm thereof, and provides the voltage signal to the buffer 420 .

[0111] The buffer 420 outputs the voltage signal from the current-voltage conversion section 410 to the subtractor 430. The driving force for driving the subsequent stage can be increased by the buffer 420. In addition, the buffer 420 can isolate noise caused by the switching operation of the subsequent stage.

[0112] The subtractor 430 reduces the level of the voltage signal from the buffer 420 according to the row driving signal from the driving circuit 211. The subtractor 430 supplies the voltage signal at the reduced level to the quantizer 440.

[0113] The quantizer 440 quantizes the voltage signal from the subtractor 430 into a digital signal, and outputs the digital signal as a detection signal to the transmission section 450 .

[0114] The transmission section 450 transmits the detection signal from the quantizer 440 to the signal processing section 220 and the like. When an address event is detected, the transmission section 450 provides a request for requesting transmission of the detection signal to the arbitrator 213. Then, when the transmission section 450 receives a response to the request from the arbitrator 213, the transmission section 450 provides the detection signal to the driving circuit 211 and the signal processing section 220.

[0115] [Configuration Example of Current-Voltage Converter]

[0116] Fig. 9 : is a circuit diagram showing a configuration example of a current-voltage conversion section 410 according to the first embodiment of the present technology. The current-voltage conversion section 410 includes N-type transistors 411 and 413 and a P-type transistor 412. As these transistors, for example, MOS transistors are used.

[0117] The source of the N-type transistor 411 is connected to the light shielding portion 330, and the drain is connected to the power supply terminal. Between the power supply terminal and the ground terminal, the P-type transistor 412 is connected in series with the N-type transistor 413. In addition, the connection node between the P-type transistor 412 and the N-type transistor 413 is connected to the gate of the N-type transistor 411 and the input terminal of the buffer 420. In addition, a predetermined bias voltage Vbias is applied to the gate of the P-type transistor 412.

[0118] The drains of the N-type transistors 411 and 413 are connected to the power supply side. This circuit is called a "source follower". The two connected source followers forming a loop convert the current from the light shielding portion 330 into a voltage signal corresponding to its logarithm. In addition, the P-type transistor 412 supplies a constant current to the N-type transistor 413.

[0119] [Construction example of subtractor and quantizer]

[0120] Fig.104 is a circuit diagram showing a configuration example of a subtractor 430 and a quantizer 440 according to the first embodiment of the present technology. The subtractor 430 includes capacitors 431 and 433, an inverter 432, and a switch 434. In addition, the quantizer 440 includes a comparator 441.

[0121] One end of the capacitor 431 is connected to the output terminal of the buffer 420, and the other end is connected to the input terminal of the inverter 432. The capacitor 433 is connected in parallel to the inverter 432. The switch 434 opens and closes a path connecting both ends of the capacitor 433 to each other according to a driving signal.

[0122] The inverter 432 inverts the voltage signal input through the capacitor 431. The inverter 432 outputs the inverted signal to the non-inverting input terminal (+) of the comparator 441.

[0123] When the switch 434 is turned on, the voltage signal V is input to the buffer 420 side of the capacitor 431. init , and the other side is used as a virtual ground terminal. For convenience, the potential of the virtual ground terminal is considered to be zero. Here, the potential Q accumulated in the capacitor 431 init It is represented by the following expression, where C1 represents the capacitance of the capacitor 431. Meanwhile, both ends of the capacitor 433 are short-circuited, so no charge is accumulated in the capacitor 433.

[0124] Q init =C1×V init ...Expression 1

[0125] Next, consider that switch 434 is turned off and the voltage on the buffer 420 side of capacitor 431 becomes V after The charge Q accumulated in capacitor 431 after It is represented by the following expression.

[0126] Q after =C1×V after ...Expression 2

[0127] Meanwhile, the charge Q2 accumulated in the capacitor 433 is expressed by the following expression, where V out Indicates the output voltage.

[0128] Q2=-C2×V out ...Expression 3

[0129] Here, since the total amount of charge in the capacitors 431 and 433 does not change, the following expression is established.

[0130] Q init =Q after +Q2...Expression 4

[0131] When Expression 1 to Expression 3 are replaced with Expression 4 to be converted, the following expression is obtained.

[0132] V out =-(C1 / C2)×(V after -V init )...Expression 5

[0133] Expression 5 represents the subtraction operation of the voltage signal, and the gain of the subtraction result is C1 / C2. Since the gain is generally expected to be maximum, it is preferred to set C1 to a larger value, and it is preferred to set C2 to a smaller value. However, when C2 is extremely small, the kTC noise increases, which may cause the noise characteristic to deteriorate. Therefore, the capacitor C2 can only be reduced within the range of achieving acceptable noise. In addition, since the address event detection unit 400 including the subtractor 430 is provided in each pixel block, the capacitors C1 and C2 have space limitations. Taking these issues into consideration, the values ​​of the capacitors C1 and C2 are determined.

[0134] The comparator 441 compares the voltage signal from the subtractor 430 with a threshold voltage Vth which is applied to the inverting input terminal (−) and indicates a predetermined threshold value. The comparator 441 outputs a signal indicating the comparison result to the transmission section 450 as a detection signal.

[0135] In addition, the gain A of the entire address event detection unit 400 described above is expressed by the following expression, where CG log represents the conversion gain of the current-voltage conversion section 410 , and the gain of the buffer 420 is 1.

[0136] [Mathematical formula 1]

[0137]

[0138] In the above expression, i photo _n represents the photocurrent of the nth pixel, for example, in amperes (A). N represents the number of pixels in the pixel block (the light-shielded pixel block 310 and the open pixel block 340).

[0139] [Configuration example of column ADC]

[0140] Fig.11 2 is a block diagram showing a configuration example of the column ADC 230 according to the first embodiment of the present technology. The column ADC 230 includes an ADC 231 in each column of the pixel blocks (light shielding pixel blocks 310 and opening pixel blocks 340).

[0141] ADC 231 converts the analog pixel signal SIG provided through the vertical signal line VSL into a digital signal. The pixel signal SIG is converted into a digital signal having more bits than the bits included in the detection signal. For example, when the detection signal has 2 bits, the pixel signal is converted into a digital signal having 3 bits or more (e.g., 16 bits). ADC 231 provides the generated digital signal to the signal processing unit 220.

[0142] [Operation example of solid-state imaging element]

[0143] Fig.12 1 is a timing diagram showing an example of the operation of the solid-state imaging element 200 according to the first embodiment of the present technology. Assume that at time T0, the control unit 130 sets the imaging mode. The drive circuit 211 sets all the control signals OFGn to a high level to turn on the OFG transistors of all the open pixels. In this way, the sum of the photocurrents of all the open pixels is provided to the address event detection unit 343. At the same time, since all the transfer signals TRGn are at a low level, the transfer transistors of all the open pixels are in an off state.

[0144] Then, it is assumed that at time T1, the address event detection unit 343 detects an address event and outputs a detection signal of a high level. Here, it is assumed that the detection signal is a 1-bit signal indicating that an on event has been detected.

[0145] At time T2, when the drive circuit 211 receives the detection signal, the drive circuit 211 sets all the control signals OFGn to a low level to stop supplying the photocurrent to the address event detection unit 343. In addition, the drive circuit 211 sets the selection signal SEL to a high level and sets the reset signal RST to a high level within a specific pulse period, thereby initializing the floating diffusion layer. The pixel signal generation unit 341 outputs the voltage at the time of initialization as a reset level, and the ADC 231 converts the reset level into a digital signal.

[0146] At time T3 after the reset level conversion, the drive circuit 211 provides a high-level transmission signal TRG1 within a specific pulse period, thereby controlling the first pixel to output the voltage as the signal level. The ADC 231 converts the signal level into a digital signal. The signal processing unit 220 obtains the difference between the reset level and the signal level as a net pixel signal. This process is called "CDS processing".

[0147] At time T4 after the signal level conversion, the driving circuit 211 provides a high-level transmission signal TRG2 in a specific pulse period to control the second pixel output signal level. The signal processing unit 220 obtains the difference between the reset level and the signal level as a net pixel signal. Similar processing is performed thereafter to sequentially output the pixel signals of each open pixel in the open pixel block 340.

[0148] When outputting all pixel signals, the driving circuit 211 sets all control signals OFGn to a high level to turn on the OFG transistors of all open pixels.

[0149] Note that in the calibration mode, regardless of the presence or absence of an address event, the drive circuit 211 drives all light-shielded pixels so that the light-shielded pixels sequentially output pixel signals.

[0150] Fig.13 2 is a block diagram showing a configuration example of the signal processing section 220 according to the first embodiment of the present technology. The signal processing section 220 includes a switch 221 , a correction processing section 222 , a correction value calculation section 223 , and a correction value holding section 224 .

[0151] The switch 221 switches the destination of the pixel signal from the column ADC 230 according to the mode signal MODE from the control unit 130. In the case of the calibration mode, the switch 221 outputs the pixel signal of the open pixel to the correction value calculation unit 223. In the case of the imaging mode, the switch 221 outputs the pixel signal of the light-shielded pixel to the correction processing unit 222.

[0152] The correction value calculation section 223 calculates the statistics (e.g., average value or total) of the pixel signals of the light-shielded pixels 360, thereby calculating the correction value for noise correction for each open pixel. The correction value calculation section 223 then stores the calculated correction value in the correction value holding section 224. The correction value holding section 224 holds the correction value for each open pixel.

[0153] The correction processing section 222 corrects the pixel signal of the opening pixel 370 by using the correction value. The correction processing section 222 performs, for example, a correction process of subtracting the correction value corresponding to the pixel in question from the pixel signal from the opening pixel 370. Through this correction process, the dark current noise and offset noise generated in the opening pixel 370 are removed. The correction processing section 222 provides the processed signal to the recording section 120. In addition, the signal processing section 220 performs processing other than the correction processing, such as CDS processing or image recognition processing, as needed. Fig.13 Illustration of circuits for performing CDS processing, etc. is omitted.

[0154] Fig.141 is a flowchart showing an example of the operation of the solid-state image pickup element 200 according to the first embodiment of the present technology. For example, when the calibration mode is set using the mode signal MODE, the operation starts.

[0155] The drive circuit 211 in the solid-state imaging element 200 drives each light-shielded pixel 360 so that the light-shielded pixel 360 outputs a pixel signal (step S901). Then, the signal processing section 220 calculates correction values ​​based on these pixel signals and holds the correction values ​​(step S902).

[0156] The solid-state imaging element 200 determines whether the imaging mode has been set using the mode signal MODE (step S903 ). If the imaging mode has not been set (step S903 : No), the solid-state imaging element 200 repeats step S903 and subsequent steps.

[0157] On the other hand, in the case where the imaging mode has been set (step S903: Yes), the drive circuit 211 determines whether an address event has occurred in any of the opening pixel blocks 340 (step S904). In the case where an address event has occurred (step S904: Yes), the drive circuit 211 controls each pixel in the opening pixel block 340 where the address event has occurred to sequentially output pixel signals (step S905). Then, the signal processing section 220 corrects these pixel signals by using the correction value (step S906).

[0158] When there is no address event (step S904 : No) or after step S906 , the solid-state imaging element 200 repeatedly executes step S904 and subsequent steps.

[0159] In this way, according to the first embodiment of the present technology, since the light-shielded pixel 360 outputs a signal based on the noise generated in the open pixel 370, the signal processing unit 220 can remove the noise from the pixel signal of the open pixel 370 by using the signal. In this way, the signal quality of the pixel signal can be improved.

[0160] [First Modification]

[0161] In the first embodiment described above, elements other than the photoelectric conversion element 333 are arranged on the circuit chip 202. However, in this configuration, as the number of pixels increases, the circuit chip 202 may have a larger circuit scale. The solid-state imaging element 200 according to the first modification of the first embodiment is different from the first embodiment in that the circuit chip 202 has a reduced circuit scale.

[0162] Fig.15is a circuit diagram showing a configuration example of a light-shielding pixel block 310 according to a first modification of the first embodiment of the present technology. The light-shielding pixel block 310 according to the first modification of the first embodiment is different from the first embodiment in that a reset transistor 321, a floating diffusion layer 324, and a plurality of light-shielding portions 330 are provided on a light-receiving chip 201. The remaining elements are provided on a circuit chip 202. Note that, similar to the case of the light-shielding pixel block 310, the elements in the opening pixel block 340 are also provided on the chip.

[0163] In this way, according to the first modification of the first embodiment of the present technology, since the reset transistor 321 and the like and the plurality of light shielding portions 330 are provided on the light receiving chip 201 , the circuit scale of the circuit chip 202 can be reduced compared to the first embodiment.

[0164] [Second Modification]

[0165] In the first modification of the first embodiment described above, the reset transistor 321 and the plurality of light shielding portions 330 are provided on the light receiving chip 201. However, as the number of pixels increases, the circuit chip 202 may have a larger circuit scale. The solid-state imaging element 200 according to the second modification of the first embodiment is different from the first modification of the first embodiment in that the circuit scale of the circuit chip 202 is further reduced.

[0166] Fig.16 is a circuit diagram showing a construction example of a light-shielding pixel block 310 according to a second variant of the first embodiment of the present technology. The light-shielding pixel block 310 according to the second variant of the first embodiment is different from the first variant of the first embodiment in that N-type transistors 411 and 413 are also provided on the light-receiving chip 201. In this way, by providing only N-type transistors in the light-receiving chip 201, the number of processes for forming transistors can be reduced compared to the case where both N-type transistors and P-type transistors are provided. In this way, the manufacturing cost of the light-receiving chip 201 can be reduced. Note that, similar to the case of the light-shielding pixel block 310, the elements in the opening pixel block 340 are also provided on the chip.

[0167] In this way, according to the second modification of the first embodiment of the present technology, since the N-type transistors 411 and 413 are further provided on the light receiving chip 201 , the circuit scale of the circuit chip 202 can be reduced compared with the first modification of the first embodiment.

[0168] [Third Modification]

[0169] In the second modification of the first embodiment described above, N-type transistors 411 and 413 are further provided on the light receiving chip 201. However, as the number of pixels increases, the circuit chip 202 may have a larger circuit scale. The solid-state imaging element 200 according to the third modification of the first embodiment is different from the second modification of the first embodiment in that the circuit scale of the circuit chip 202 is further reduced.

[0170] Fig.17 1 is a circuit diagram showing a configuration example of a light-shielding pixel block 310 according to a third modification of the first embodiment of the present technology. The light-shielding pixel block 310 according to the third modification of the first embodiment is different from the second modification of the first embodiment in that an amplifying transistor 322 and a selecting transistor 323 are further provided on the light receiving chip 201. That is, all elements of the pixel signal generating section 320 are provided on the light receiving chip 201.

[0171] In this way, according to the third modification of the first embodiment of the present technology, since the pixel signal generation section 320 is provided on the light receiving chip 201 , the circuit scale of the circuit chip 202 can be reduced compared with the second modification of the first embodiment.

[0172] [Fourth Modification]

[0173] In the first embodiment described above, in the calibration mode, the correction value is calculated. It is also possible to test whether the opening pixel has an abnormality. The solid-state imaging element 200 according to the fourth variation of the first embodiment is different from the first embodiment in that each pixel includes a circuit for testing whether an abnormality exists.

[0174] Fig.18 1 is a block diagram showing a configuration example of an address event detection unit 400 in a light shielding pixel block 310 according to a fourth modification of the first embodiment of the present technology. The address event detection unit 400 according to the fourth modification of the first embodiment differs from the first embodiment in that a selector 460 is further included.

[0175] The selector 460 selects a predetermined test signal TIN or a voltage signal from the current-voltage conversion section 410. The selector 460 selects the test signal TIN or the voltage signal according to a selection signal SEL from the driving circuit 211, and provides the signal to the buffer 420.

[0176] Note that the address event detection section 343 in the opening pixel block 340 is configured similarly to the address event detection section 400 in the light-shielding pixel block 310 .

[0177] In the calibration mode, the drive circuit 211 uses the selection signal SEL to control the selector 460 to select the test signal TIN for all pixels. Since no address event is detected when an abnormality occurs in the buffer 420 or the subsequent stage, the signal processing section 220 can determine the presence or absence of an abnormality based on the detection signal.

[0178] In addition, regardless of the presence or absence of an address event, the selector 460 can force all normal light-shielded pixels 360 to output a detection signal. In this way, regardless of the presence or absence of an address event, a pixel signal is output from the light-shielded pixel 360.

[0179] Note that although the selector 460 is provided between the current-voltage conversion section 410 and the buffer 420, the present technology is not limited to this configuration. For example, the selector 460 may be provided between the buffer 420 and the subtractor 430 or between the subtractor 430 and the quantizer 440. In addition, two or more selectors 460 may be provided. In addition, the first to third modified examples are also applicable to the solid-state imaging element 200 of the fourth modified example.

[0180] In this way, according to the fourth modification of the first embodiment of the present technology, since the selector 460 for selecting the test signal or the voltage signal is provided, the signal processing section 220 can determine whether or not there is an abnormality for each pixel.

[0181] <2. Second Embodiment>

[0182] In the first embodiment described above, the current-voltage conversion unit 410 converts the dark current into a voltage signal through a single loop circuit. However, since the dark current is usually very small, sufficient conversion gain may not be obtained through a single loop circuit. The current-voltage conversion unit 410 of the second embodiment is different from the first embodiment in that the current-voltage conversion is performed through a multi-stage loop circuit.

[0183] Fig.19 1 is a circuit diagram showing a configuration example of a pixel signal generating section 320 and a light shielding section 330 according to a second embodiment of the present technology. Each of the plurality of light shielding sections 330 of the second embodiment is different from that of the first embodiment in that dark current is supplied to the address event detecting section 400 through different signal lines.

[0184] Fig. 201 is a circuit diagram showing a configuration example of a current-voltage conversion unit 410 according to a second embodiment of the present technology. The current-voltage conversion unit 410 of the second embodiment includes a plurality of N-type transistors 414, a plurality of N-type transistors 415, a current source 416, and N-type transistors 417 and 418. As the N-type transistors 414, 415, 417, and 418, for example, MOS transistors are used. An N-type transistor 415 and an N-type transistor 417 are set for each light-shielding pixel 360. When the number of light-shielding pixels 360 in the light-shielding pixel block 310 is N, N N-type transistors 415 and N N-type transistors 417 are set.

[0185] The N-type transistors 414 and 415 are connected in series between the buffer 420 and the corresponding light shielding portion 330. In addition, between the power supply terminal and the ground terminal, the current source 416 is connected in series with the N-type transistors 417 and 418. In addition, the gate of the N-type transistor 418 is commonly connected to the respective sources of the N N-type transistors 415. The gate of the N-type transistor 417 is commonly connected to the respective connection nodes between the N N-type transistors 415 and the N-type transistor 414.

[0186] With the above configuration, a two-stage loop is formed, namely, a loop circuit including N-type transistors 415 and 418 and a loop circuit including N-type transistors 414 and 417. With this two-stage loop circuit, the conversion gain for converting the dark current into a voltage signal is twice the conversion gain using a single-stage loop circuit. In addition, the average value of the N voltage signals obtained by converting the N dark currents is output to the buffer 420.

[0187] Note that the first to fourth modifications are also applicable to the solid-state imaging element 200 of the second embodiment.

[0188] In this way, according to the second embodiment of the present technology, since the current-voltage conversion unit 410 converts the dark current into a voltage signal using a two-stage loop circuit, the conversion gain is twice the conversion gain using a single-stage loop circuit, thereby enabling a high-level voltage signal to be achieved.

[0189] <3. Third embodiment>

[0190] In the above-described first embodiment, both the light-shielding pixels 360 and the opening pixels 370 are arranged on the same plane of the light receiving chip 201. However, in this configuration, when the area of ​​the light receiving chip 201 is fixed, as the area of ​​the light-shielding region where the light-shielding pixels 360 are arranged increases, the area of ​​the opening region where the opening pixels 370 are arranged decreases. The solid-state imaging element 200 of the third embodiment is different from that of the first embodiment in that only the light-shielding pixels 360 are arranged on the light receiving surface, and the light-shielding pixels 360 are arranged on the surface facing the light receiving surface.

[0191] Fig.21 It is an example of a cross-sectional view of a solid-state imaging element 200 according to a third embodiment of the present technology. The cross-sectional view represents a cross-sectional view of a predetermined cross section parallel to the Z direction. The solid-state imaging element 200 has a pair of planes facing each other. These planes are perpendicular to the Z direction. One plane serves as a light receiving surface on which an opening pixel 370 is arranged. In addition, a light shielding pixel 360 is arranged on another plane. In the case of a stacked structure, the opening pixel 370 is arranged on the light receiving chip 201, and the light shielding pixel 360 is arranged on the circuit chip 202. The surface on which the light shielding pixel 360 is arranged faces the package, for example, and is not exposed to light. In addition, the light entering the light receiving surface is blocked by the wiring or circuit, thereby preventing the light from reaching the light shielding pixel 360 on the other surface. Therefore, a light shielding member is not required.

[0192] Fig. 22 2 shows an example of a plan view of a light receiving chip 201 and a circuit chip 202 according to a third embodiment of the present technology. Fig. 22 a is an example of a plan view of the light receiving chip 201, Fig. 22 b is an example of a plan view of the circuit chip 202 .

[0193] In the opening region in the light receiving chip 201, a plurality of opening pixels 370 are arranged in a two-dimensional lattice pattern. In addition, in the light shielding region in the circuit chip 202, a plurality of light shielding pixels 360 are arranged in a two-dimensional lattice pattern. In the light shielding region, for example, the same number of light shielding pixels 360 as the opening pixels 370 are arranged.

[0194] Note that the number of light-shielded pixels 360 can also be smaller than the number of open pixels 370. In this case, for example, Fig.23 As shown in a of FIG. 1 , a plurality of light-shielding pixel blocks 310 each including N light-shielding pixels 360 can also be arranged at intervals from each other in a two-dimensional grid pattern. Fig.23 As shown in b, the light-shielding pixels 360 can also be arranged irregularly.

[0195] Fig.24 : is a block diagram showing a configuration example of an opening pixel 370 and a light shielding pixel 360 according to a third embodiment of the present technology.

[0196] The open pixel 370 includes a photoelectric conversion element 372, a current-voltage conversion section 480, a buffer 471, a subtractor 472, a quantizer 473, and a transfer section 474. Figure 8 The corresponding circuit in the illustrated address event detection section 400 is similarly configured with a buffer 471 , a subtractor 472 , a quantizer 473 , and a transmission section 474 .

[0197] The photoelectric conversion element 372 of the third embodiment supplies a photocurrent to the current-voltage conversion section 480 .

[0198] In addition, the light-shielded pixel 360 of the third embodiment includes a photoelectric conversion element 333 and an OFG transistor 332. The OFG transistor 332 outputs the charge from the photoelectric conversion element 333 to the current-voltage conversion section 480 according to the control signal OFGn. In this way, a dark current flows from the current-voltage conversion section 480 to the photoelectric conversion element 333. This dark current is used as a correction signal for correcting dark current noise.

[0199] In addition, the solid-state imaging element 200 of the third embodiment is not set to the calibration mode. In address event detection, the drive circuit 211 controls the pixel using the control signal OFGn to output the charge from the photoelectric conversion element 333 to the current-voltage conversion section 480 .

[0200] The current-voltage conversion section 480 converts the difference between the dark current and the photocurrent generated by the photoelectric conversion element 372 into a voltage signal. In this way, dark current noise can be reduced.

[0201] As described above, the open pixel 370 of the third embodiment detects the presence or absence of an address event but does not output a pixel signal. In addition, the light shielding pixel 360 of the third embodiment outputs a dark current but does not output an address event detection signal or a pixel signal.

[0202] Fig.25 4 is a circuit diagram showing a configuration example of a current-voltage conversion section 480 according to a third embodiment of the present technology. The current-voltage conversion section 480 of the third embodiment includes N-type transistors 481 , 482 , 484 , and 485 , and a current source 483 .

[0203] N-type transistors 481 and 482 are connected in series between a terminal having a power supply voltage VDD and the photoelectric conversion element 372. In addition, a drain of the N-type transistor 481 is connected to the light-shielded pixel 360. A current source 483 and N-type transistors 484 and 485 are connected in series between a terminal having a power supply voltage VDD and a ground terminal.

[0204] In addition, the gate of the N-type transistor 481 is connected to the connection node between the current source 483 and the N-type transistor 484. The gate of the N-type transistor 482 is connected to the connection node between the N-type transistors 484 and 485. The gate of the N-type transistor 484 is connected to the connection node between the N-type transistors 481 and 482. The gate of the N-type transistor 485 is connected to the connection node between the N-type transistor 482 and the photoelectric conversion element 372. In addition, the connection node between the current source 483 and the N-type transistor 484 is connected to the buffer 471.

[0205] With the above configuration, the difference between the dark current generated in the light-shielded pixel 360 and the photocurrent generated in the photoelectric conversion element 372 is converted into a voltage signal. By generating a voltage signal using the difference between the dark current and the photocurrent, dark current noise in the detection signal obtained from the voltage signal can be reduced.

[0206] Note that although the opening pixel 370 and the light shielding pixel 360 of the third embodiment do not output pixel signals, they may be configured to output pixel signals and correct the pixel signals with correction values ​​as in the first embodiment.

[0207] In this way, according to the third embodiment of the present technology, the opening pixels 370 are arranged on one plane of a pair of planes facing each other, and the shading pixels 360 are arranged on the other plane, so that the area in which the opening pixels 370 are arranged can be widened compared to the case where these pixels are arranged on the same plane.

[0208] Furthermore, the current-voltage converter 410 converts the difference between the dark current from the light-shielded pixel 360 and the photocurrent generated in the photoelectric conversion element 372 of the open pixel 370 into a voltage signal, thereby being able to remove dark current noise in the voltage signal.

[0209] <4. Fourth embodiment>

[0210] In the first embodiment described above, noise such as dark current noise is removed from the pixel signal of the opening pixel 370. However, in address event detection, detection errors may occur due to the influence of dark current noise, etc. The solid-state imaging element 200 of the fourth embodiment is different from the first embodiment in that the detection accuracy of the address event is improved.

[0211] Fig.26 1 is a block diagram showing a configuration example of a solid-state imaging element 200 according to a fourth embodiment of the present technology. The solid-state imaging element 200 of the fourth embodiment is different from that of the first embodiment in that a DAC 214 is further included.

[0212] The DAC 214 performs DA conversion on the control signal from the signal processing section 220 and generates a threshold voltage Vth. The DAC 214 supplies the threshold voltage Vth to the open pixel 370 and the light shielding pixel 360 in the pixel array section 300 .

[0213] Fig. 27 2 is a block diagram showing a configuration example of a signal processing section 220 according to a fourth embodiment of the present technology. The signal processing section 220 of the fourth embodiment is different from that of the first embodiment in that a set value register 225 and a threshold value adjustment section 226 are further included.

[0214] The threshold adjustment section 226 adjusts the threshold voltage Vth indicating the threshold value using the control signal sent to the DAC 214. The threshold adjustment section 226 receives respective detection signals from a plurality of light-shielded pixels in the pixel array section 300.

[0215] In the calibration mode, the threshold adjustment unit 226 obtains the detection signal detection frequency and reads the set value corresponding to the detection frequency from the set value register 225. Then, the threshold adjustment unit 226 updates the threshold voltage Vth to a voltage representing the set value using the control signal. By appropriately updating the threshold voltage Vth, address event detection errors caused by dark current noise or offset noise can be prevented.

[0216] The set value register 225 holds a set value based on the detection frequency. The set value includes an upper limit set value indicating an upper threshold value and a lower limit set value indicating a lower threshold value. For example, the higher the turn-on event output frequency is, the lower the upper limit set value is held. On the other hand, the higher the turn-off event detection frequency is, the higher the lower limit set value is held.

[0217] Note that the setting value register 225 can also store only the upper limit setting value. In addition, while the threshold value adjustment unit 226 reads the setting value from the setting value register 225, the threshold value adjustment unit 226 can also obtain the setting value by performing a predetermined operation on the detection frequency. In this case, the setting value register 225 is not required. In addition, the first to fourth modified examples are also applicable to the solid-state imaging element 200 of the fourth embodiment.

[0218] In this way, according to the fourth embodiment of the present technology, the threshold adjustment unit 226 updates the threshold voltage to a value based on the address event detection frequency of the light-shielded pixel 360, thereby preventing address event detection errors due to noise, thereby improving detection accuracy.

[0219] [Image Pickup Device (Scanning Type) According to Fifth Embodiment]

[0220] The camera 20 according to the first configuration example described above is an asynchronous camera for reading out events by an asynchronous readout system. However, the event readout system is not limited to the asynchronous readout system and may be a synchronous readout system. The camera to which the synchronous readout system is applied is a scanning camera, which is the same as a normal camera for taking images at a predetermined frame rate.

[0221] Fig.28 : is a block diagram showing a configuration example of an image pickup device according to a second configuration example used as the image pickup device 20 in the image pickup system 10 to which the technology according to the present disclosure is applied, that is, a scanning type image pickup device.

[0222] like Fig.28 As shown, the image pickup device 20 according to the second configuration example, which serves as the image pickup device of the present disclosure, includes a pixel array section 21 , a drive section 22 , a signal processing section 25 , a readout region selection section 27 , and a signal generation section 28 .

[0223] The pixel array section 21 includes a plurality of pixels 30. The plurality of pixels 30 output output signals according to the selection signals from the readout region selection section 27. The plurality of pixels 30 include Figure 5 The light receiving unit 342 is shown. Figure 5 As shown, the plurality of pixels 30 (light receiving unit 342) share the pixel signal generating unit 341 and the address event detecting unit 343. The plurality of pixels 30 output signals corresponding to the amount of change in light intensity. Fig.28 As shown, the plurality of pixels 30 may be two-dimensionally arranged in a matrix.

[0224] The driving section 22 drives each of the plurality of pixels 30 so that the pixel 30 outputs a pixel signal generated by the corresponding pixel 30 to the signal processing section 25. Note that the driving section 22 and the signal processing section 25 are circuit sections for acquiring grayscale information. Therefore, in the case of acquiring only event information, the driving section 22 and the signal processing section 25 may be omitted.

[0225] The readout area selection section 27 selects some pixels from the plurality of pixels 30 included in the pixel array section 21. Specifically, the readout area selection section 27 determines the selection area based on a request from the pixel 30 in the pixel array section 21. For example, the readout area selection section 27 selects any one or more rows included in the two-dimensional matrix structure corresponding to the pixel array section 21. The readout area selection section 27 sequentially selects one or more rows based on a preset cycle. In addition, the readout area selection section 27 can determine the selection area based on a request from the pixel 30 in the pixel array section 21.

[0226] The signal generating section 28 generates an event signal corresponding to an active pixel in which an event has been detected in the selected pixel based on the output signal of the pixel selected by the readout area selecting section 27. The above-mentioned event refers to an event in which the light intensity changes. The active pixels are pixels in which the amount of change in light intensity corresponding to the output signal exceeds or falls below a preset threshold value. For example, the signal generating section 28 compares the output signal from the pixel with a reference signal, and detects a pixel that outputs a signal greater than or less than the reference signal as an active pixel. The signal generating section 28 generates an event signal corresponding to an active pixel.

[0227] The signal generating section 28 can include, for example, a column selecting circuit configured to arbitrate signals input to the signal generating section 28. Furthermore, the signal generating section 28 can output not only information about active pixels that have detected an event, but also information about inactive pixels that have not detected an event.

[0228] The signal generating section 28 outputs address information and time stamp information (e.g., (X, Y, T)) about the active pixel that has detected the event through the output line 15. However, the data output from the signal generating section 28 may be not only address information and time stamp information but also information in a frame format (e.g., (0, 0, 1, 0, ...)).

[0229] <5. Application examples of mobile objects>

[0230] The technology according to the present disclosure (the present technology) is applicable to various products. For example, the technology according to the present disclosure can be implemented as a device installed on any type of mobile body, such as: a car, an electric car, a hybrid car, a motorcycle, a bicycle, a personal mobile device, an airplane, a drone, a ship, and a robot.

[0231] Fig.29 : is a block diagram showing a schematic configuration example of a vehicle control system as an example of a moving body control system to which the technology according to the embodiment of the present disclosure can be applied.

[0232] The vehicle control system 12000 includes a plurality of electronic control units connected to each other via a communication network 12001. Fig.29 In the example shown, 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. In addition, as a functional configuration of the integrated control unit 12050, a microcomputer 12051, a sound / image output unit 12052, and an in-vehicle network interface (I / F: Interface) 12053 are shown.

[0233] The drive system control unit 12010 controls the operation of the devices related to the drive system of the vehicle according to various programs. For example, the drive system control unit 12010 functions as a control device for the following devices: a drive force generating device such as an internal combustion engine or a drive motor for generating the drive force of the vehicle; a drive force transmitting mechanism for transmitting the drive force to the wheels; a steering mechanism for adjusting the steering angle of the vehicle; and a braking device for generating the braking force of the vehicle.

[0234] The body system control unit 12020 controls the operation of various devices installed in the vehicle body according to various programs. For example, the body system control unit 12020 functions as a control device for the following devices: a keyless entry system; a smart key system; a power window device; or various lights such as a headlight, a reverse light, a brake light, a turn signal, or a fog light. In this case, it is possible to input radio waves or signals of various switches transmitted from a mobile device that replaces the key to the body system control unit 12020. The body system control unit 12020 receives these input radio waves or signals, and controls the door lock device, power window device, or lights of the vehicle.

[0235] The vehicle exterior information detection unit 12030 detects information of the exterior of the vehicle including the vehicle control system 12000. For example, the vehicle exterior information detection unit 12030 is connected to the camera unit 12031. The vehicle exterior information detection unit 12030 causes the camera unit 12031 to capture an image of the exterior of the vehicle and receives the captured image. Based on the received image, the vehicle exterior information detection unit 12030 can perform detection processing or distance detection processing on objects such as pedestrians, vehicles, obstacles, signs, or text on the road surface.

[0236] The imaging unit 12031 is an optical sensor for receiving light and outputting an electrical signal corresponding to the amount of light received. The imaging unit 12031 can output the electrical signal as an image, or can output the electrical signal as distance measurement information. In addition, the light received by the imaging unit 12031 may be visible light, or may be non-visible light such as infrared rays.

[0237] The in-vehicle information detection unit 12040 detects information about the interior of the vehicle. For example, the in-vehicle information detection unit 12040 is connected to a driver state detection unit 12041 for detecting a driver state. For example, the driver state detection unit 12041 includes a camera for photographing the driver. Based on the detection information input from the driver state detection unit 12041, the in-vehicle information detection unit 12040 can calculate the driver's fatigue level or the driver's concentration level, or can determine whether the driver is dozing off.

[0238] The microcomputer 12051 can calculate the control target value of the driving force generating device, the steering mechanism or the braking device based on the information outside or inside the vehicle obtained by the vehicle outside information detection unit 12030 or the vehicle inside information detection unit 12040, and can output a control command to the driving system control unit 12010. For example, the microcomputer 12051 can perform cooperative control for realizing the functions of the advanced driver assistance system (ADAS), which includes: collision avoidance or impact reduction of the vehicle, following driving based on the following distance, speed maintenance driving, collision warning of the vehicle or lane departure warning of the vehicle, etc.

[0239] In addition, the microcomputer 12051 can control the driving force generating device, steering mechanism or braking device, etc. based on the information outside or inside the vehicle obtained by the external information detection unit 12030 or the internal information detection unit 12040, thereby performing collaborative control for realizing automatic driving that enables the vehicle to drive autonomously without relying on the driver's operation.

[0240] In addition, based on the information outside the vehicle acquired by the vehicle exterior information detection unit 12030, the microcomputer 12051 can output a control command to the body system control unit 12020. For example, the microcomputer 12051 can control the headlights and switch from high beam to low beam according to the position of the preceding vehicle or the oncoming vehicle detected by the vehicle exterior information detection unit 12030, thereby performing cooperative control for anti-glare.

[0241] The sound / image output unit 12052 sends an output signal of at least one of sound and image to an output device, which can visually or auditorily notify passengers on the vehicle or the outside of the vehicle of information. Fig.29 In the example of FIG. 1 , as output devices, an audio speaker 12061, a display portion 12062, and an instrument panel 12063 are shown. For example, the display portion 12062 may include at least one of an on-board display and a head-up display.

[0242] Fig.30 This is a diagram showing an example of the installation position of the camera unit 12031.

[0243] exist Fig.30 In the figure, the camera unit 12031 includes camera units 12101, 12102, 12103, 12104 and 12105.

[0244] The camera units 12101, 12102, 12103, 12104 and 12105 are, for example, arranged at the following positions: the front nose, rearview mirror, rear bumper and trunk door of the vehicle 12100, and the upper part of the windshield in the vehicle compartment. The camera unit 12101 arranged at the front nose and the camera unit 12105 arranged at the upper part of the windshield in the vehicle compartment mainly acquire the front image of the vehicle 12100. The camera units 12102 and 12103 arranged on the rearview mirror mainly acquire the side image of the vehicle 12100. The camera unit 12104 arranged on the rear bumper or the trunk door mainly acquires the rear image of the vehicle 12100. The camera unit 12105 arranged at the upper part of the windshield in the vehicle compartment is mainly used to detect the preceding vehicle, pedestrians, obstacles, traffic lights, traffic signs or lanes, etc.

[0245] By the way, Fig.30 Examples of the imaging ranges of the imaging units 12101 to 12104 are shown. The imaging range 12111 indicates the imaging range of the imaging unit 12101 disposed on the front nose. The imaging ranges 12112 and 12113 respectively indicate the imaging ranges of the imaging units 12102 and 12103 disposed on the rearview mirror. The imaging range 12114 indicates the imaging range of the imaging unit 12104 disposed on the rear bumper or the trunk door. For example, by superimposing the image data acquired by the imaging units 12101 to 12104, a bird's-eye view image of the vehicle 12100 viewed from above is obtained.

[0246] At least one of the imaging units 12101 to 12104 may have a function of acquiring distance information. For example, at least one of the imaging units 12101 to 12104 may be a stereo camera composed of a plurality of imaging elements, or may be an imaging element having pixels for phase difference detection.

[0247] For example, the microcomputer 12051 can determine the distance to each three-dimensional object within the imaging range 12111 to 12114 and the change of the distance over time (relative speed relative to the vehicle 12100) based on the distance information obtained from the imaging units 12101 to 12104, thereby extracting the three-dimensional object that is closest to the vehicle 12100 on the path of the vehicle 12100 and traveling at a predetermined speed (for example, greater than or equal to 0 km / h) in the same direction as the vehicle 12100 as the leading vehicle. In addition, the microcomputer 12051 can set the following distance to be maintained in front of the leading vehicle in advance, and can perform automatic braking control (including follow-up stop control) or automatic acceleration control (including follow-up start control), etc. Therefore, cooperative control such as automatic driving for autonomous driving of the vehicle without relying on the driver's operation can be performed.

[0248] For example, based on the distance information obtained from the camera units 12101 to 12104, the microcomputer 12051 can classify the three-dimensional object data related to the three-dimensional object into three-dimensional object data of two-wheeled vehicles, ordinary vehicles, large vehicles, pedestrians, telephone poles and other three-dimensional objects, extract the classified three-dimensional object data, and use the extracted three-dimensional object data to automatically avoid obstacles. For example, the microcomputer 12051 identifies obstacles around the vehicle 12100 as obstacles that the driver of the vehicle 12100 can visually identify and obstacles that are difficult for the driver of the vehicle 12100 to visually identify. Then, the microcomputer 12051 determines the collision risk used to represent the risk of collision with each obstacle. In the case where the collision risk is greater than or equal to the set value and therefore there is a possibility of collision, the microcomputer 12051 can output a warning to the driver through the audio speaker 12061 or the display unit 12062, and perform forced deceleration or avoidance steering through the drive system control unit 12010. As a result, the microcomputer 12051 can assist driving to avoid collisions.

[0249] At least one of the camera units 12101 to 12104 may be an infrared camera that detects infrared rays. For example, the microcomputer 12051 can identify pedestrians by determining whether there are pedestrians in the images captured by the camera units 12101 to 12104. For example, such identification of pedestrians is performed by the following process: a process of extracting feature points in the images captured by the camera units 12101 to 12104 as infrared cameras; and a process of determining whether the object is a pedestrian by pattern matching a series of feature points representing the contour of the object. When the microcomputer 12051 determines that there is a pedestrian in the images captured by the camera units 12101 to 12104 and identifies the pedestrian, the sound / image output unit 12052 controls the display unit 12062 so that a rectangular contour line for emphasis is superimposed and displayed on the identified pedestrian. The sound / image output unit 12052 may also control the display unit 12062 so that an icon or the like for representing a pedestrian is displayed at a desired position.

[0250] An example of a vehicle control system to which the technology of the present disclosure is applicable has been described above. The technology of the present disclosure is applicable to the camera unit 12031 in the above-mentioned configuration. Specifically, for example, Figure 1 The imaging device 100 is applicable to the imaging unit 12031. The imaging unit 12031 to which the technology according to the present disclosure is applied can obtain an easily readable captured image, thereby reducing the fatigue of the driver.

[0251] Note that the above-described embodiments are examples for implementing the present technology, and the matters in the embodiments have a corresponding relationship with the matters defining the present invention within the scope of the claims. In a similar manner, the matters defining the present invention within the scope of the claims have a corresponding relationship with the matters represented by the same names in the embodiments of the present technology. However, the present technology is not limited to the above-described embodiments, and various modifications can be made to the embodiments without departing from the gist of the present technology.

[0252] Note that the present technology can also adopt the following configurations. (1)

[0254] A solid-state imaging element, comprising:

[0255] open pixels each configured to detect whether a change in the amount of incident light exceeds a predetermined threshold value and output a detection signal indicating a detection result; and

[0256] The light-shielding pixels are each configured to output a correction signal based on an amount of noise generated in the opening pixel. (2)

[0258] The solid-state imaging device according to (1),

[0259] Wherein, the opening pixels and the light shielding pixels are arranged on a predetermined plane. (3)

[0261] The solid-state imaging device according to (1),

[0262] wherein the opening pixels are arranged on one plane of a pair of planes facing each other, and

[0263] The light-shielding pixels are arranged on the other plane of the pair of planes. (4)

[0265] According to the solid-state imaging element described in (3),

[0266] The light-shielding pixels and the opening pixels are arranged one to one. (5)

[0268] According to the solid-state imaging element described in (3),

[0269] Wherein, on the other plane of the pair of planes, a plurality of light-shielding pixel blocks are arranged, each light-shielding pixel block includes a predetermined number of the light-shielding pixels, and

[0270] The plurality of light-shielding pixel blocks are arranged spaced apart from each other at certain intervals. (6)

[0272] According to the solid-state imaging element described in (3),

[0273] Wherein, the light-shielding pixels are arranged irregularly. (7)

[0275] The solid-state imaging device according to any one of (1) to (8), further comprising:

[0276] a signal processing section configured to perform a correction process for removing the noise from the pixel signal based on the light amount according to the correction signal,

[0277] Wherein, the open pixels also output the pixel signals respectively. (8)

[0279] The solid-state imaging device according to any one of (1) to (7),

[0280] Wherein, the light-shielding pixels respectively include:

[0281] Photoelectric conversion element;

[0282] a current-voltage conversion section configured to convert a dark current generated in the photoelectric conversion element into a voltage signal;

[0283] a quantizer configured to detect whether the amount of change of the voltage signal exceeds the threshold value; and

[0284] A pixel signal generating section is configured to generate a pixel signal as the correction signal based on the light amount. (9)

[0286] The solid-state imaging device according to (8),

[0287] Wherein, the current-voltage conversion unit converts the dark current into the voltage signal through a multi-stage loop circuit. (10)

[0289] The solid-state imaging device according to (8),

[0290] wherein the photoelectric conversion element and a part of the pixel signal generating unit are arranged on a predetermined light receiving chip, and

[0291] The rest of the pixel signal generating section, the current-voltage converting section, and the quantizer are provided on a predetermined circuit chip. (11)

[0293] The solid-state imaging device according to (8),

[0294] wherein the photoelectric conversion element, a part of the pixel signal generating unit, and a part of the current-voltage converting unit are arranged on a predetermined light receiving chip, and

[0295] The rest of the pixel signal generating section, the rest of the current-voltage converting section, and the quantizer are provided on a predetermined circuit chip. (12)

[0297] The solid-state imaging device according to (8),

[0298] wherein the photoelectric conversion element, the pixel signal generating unit, and a part of the current-voltage conversion unit are arranged on a predetermined light receiving chip, and,

[0299] The rest of the current-voltage conversion section and the quantizer are disposed on a predetermined circuit chip. (13)

[0301] The solid-state imaging device according to any one of (8) to (12),

[0302] The light-shielding pixels each further include a selector, the selector being configured to select a predetermined test signal or the voltage signal and output the selected signal as a selection signal, and

[0303] The quantizer detects whether the change amount of the selection signal exceeds the threshold. (14)

[0305] The solid-state imaging device according to (1),

[0306] Wherein, the opening pixels respectively include:

[0307] a photoelectric conversion element configured to generate a photocurrent by photoelectric conversion;

[0308] a current-voltage conversion section configured to convert a difference between the photocurrent and the dark current into a voltage signal; and

[0309] a quantizer configured to detect whether the amount of change of the voltage signal exceeds the threshold value, and

[0310] The light-shielded pixels respectively output the dark current as the correction signal. (15)

[0312] The solid-state imaging device according to (1), further comprising:

[0313] A threshold value adjustment unit is configured to adjust the threshold value based on the correction signal. (16)

[0315] A camera device, comprising:

[0316] open pixels, each configured to detect whether a change in the amount of incident light exceeds a predetermined threshold value, and to display a detection result;

[0317] light-shielded pixels each configured to output a correction signal based on an amount of noise generated in the opening pixel; and

[0318] The signal processing unit is configured to process the detection signal.

[0319] [reference numerals list]

[0320] 100 Camera Device

[0321] 110 Camera Lens

[0322] 120 Records Department

[0323] 130 Control Department

[0324] 200 Solid-state imaging element

[0325] 201 Optical Receiver Chip

[0326] 202 Circuit Chip

[0327] 211 drive circuit

[0328] 213 Arbiter 214 DAC

[0329] 220 Signal Processing Unit

[0330] 221,434 Switches

[0331] 222 Correction Processing Unit

[0332] 223 Correction value calculation unit

[0333] 224 Calibration value holding unit

[0334] 225 Set value register

[0335] 226 Threshold adjustment unit

[0336] 230 columns ADC

[0337] 231 ADC

[0338] 300 pixel array

[0339] 310 shading pixel blocks

[0340] 320,341 Pixel signal generating unit

[0341] 321 Reset transistor

[0342] 322 Amplifier Transistor

[0343] 323 Select transistor

[0344] 324 Floating Diffusion Layer

[0345] 330 shading part

[0346] 331 Pass transistor

[0347] 332 OFG transistor

[0348] 333,372 Photoelectric conversion element

[0349] 340 open pixel blocks

[0350] 342 Light receiving unit

[0351] 343,400 Address Event Detection Department

[0352] 360 shading pixels

[0353] 361,371 On-chip microlenses

[0354] 362 Shading member

[0355] 370 opening pixels

[0356] 410,480 Current-voltage conversion unit

[0357] 411,413,414,415,417,418,481,482,484,485 N-type transistors

[0358] 412 P-type transistor

[0359] 416,483 Current Sources

[0360] 420,471 Buffer

[0361] 430,472 Subtractor

[0362] 431,433 Capacitors

[0363] 432 Inverter

[0364] 440,473 Quantizer

[0365] 441 Comparator

[0366] 450,474 Transmission Department

[0367] 460 Selector

[0368] 12031 Camera Department.

Claims

1. A solid-state imaging element, comprising: an open pixel configured to detect whether a change in the amount of incident light exceeds a predetermined threshold value and output a detection signal indicating a detection result; a light-shielding pixel configured to output a correction signal based on noise amounts of dark current noise and offset noise generated in the opening pixel; and a signal processing section that performs a correction process for removing noise from the open pixel using the correction signal, wherein the opening pixels are arranged on one plane of a pair of planes facing each other, and The light-shielding pixels are arranged on the other plane of the pair of planes.

2. The solid-state imaging element according to claim 1, in, The light shielding pixels and the opening pixels are arranged one to one.

3. The solid-state imaging element according to claim 1, in, On the other plane of the pair of planes, a plurality of light-shielding pixel blocks are arranged, each light-shielding pixel block includes a predetermined number of the light-shielding pixels, and The plurality of light-shielding pixel blocks are arranged spaced apart from each other at certain intervals.

4. The solid-state imaging element according to claim 1, in, The light-shielding pixels are arranged irregularly.

5. The solid-state imaging element according to any one of claims 1 to 3, wherein: The signal processing section is configured to remove the noise from the pixel signal based on the light amount according to the correction signal, Wherein, the open pixel also outputs the pixel signal.

6. The solid-state imaging element according to any one of claims 1 to 3, in, The light-shielding pixel comprises: Photoelectric conversion element; a current-voltage conversion section configured to convert a dark current generated in the photoelectric conversion element into a voltage signal; a quantizer configured to detect whether the amount of change of the voltage signal exceeds the threshold value; and A pixel signal generating section is configured to generate a pixel signal as the correction signal based on the dark current.

7. The solid-state imaging element according to claim 6, in, The current-voltage conversion unit converts the dark current into the voltage signal through a multi-stage loop circuit.

8. The solid-state imaging element according to claim 6, in, The photoelectric conversion element and a part of the pixel signal generating section are provided on a predetermined light receiving chip, and The rest of the pixel signal generating section, the current-voltage converting section, and the quantizer are provided on a predetermined circuit chip.

9. The solid-state imaging element according to claim 6, in, The photoelectric conversion element, a part of the pixel signal generating section, and a part of the current-voltage converting section are provided on a predetermined light receiving chip, and The rest of the pixel signal generating section, the rest of the current-voltage converting section, and the quantizer are provided on a predetermined circuit chip.

10. The solid-state imaging element according to claim 6, in, The photoelectric conversion element, a part of the current-voltage conversion section, and the pixel signal generation section are provided on a predetermined light receiving chip, and, The rest of the current-voltage conversion section and the quantizer are disposed on a predetermined circuit chip.

11. The solid-state imaging element according to claim 6, in, The light-shielding pixels each further include a selector configured to select one of a predetermined test signal and the voltage signal and output the selected signal as a selection signal, and The quantizer detects whether the change amount of the selection signal exceeds the threshold.

12. The solid-state imaging element according to any one of claims 1 to 3, in, The opening pixel comprises: a photoelectric conversion element configured to generate a photocurrent by photoelectric conversion; a current-voltage conversion section configured to convert a difference between the photocurrent and the dark current into a voltage signal; and a quantizer configured to detect whether the amount of change of the voltage signal exceeds the threshold value, and The light-shielded pixel outputs the dark current as the correction signal.

13. The solid-state imaging element according to any one of claims 1 to 3, further comprising: A threshold value adjustment unit is configured to adjust the threshold value based on the correction signal.

14. A camera device, comprising: an open pixel configured to detect whether a change in the amount of incident light exceeds a predetermined threshold value and to display a detection result; a light-shielding pixel configured to output a correction signal based on noise amounts of dark current noise and offset noise generated in the opening pixel; and a signal processing unit configured to process the detection result; wherein the signal processing unit performs a correction process for removing noise from the open pixel using the correction signal, The opening pixels are arranged on one plane of a pair of planes facing each other, and The light-shielding pixels are arranged on the other plane of the pair of planes.

Images