Image sensor, electronic device, and system

Abstract

Embodiments of the present application provide an image sensor, an electronic device, and a system. The image sensor comprises a pixel array and a dynamic detection module. The pixel array comprises a plurality of pixels, and each pixel at least comprises adjacent first sub-pixel and second sub-pixel which have different exposure durations within a same frame. The dynamic detection module comprises a light intensity contrast circuit, a threshold circuit, and a comparison circuit. The light intensity contrast circuit adjusts a first output voltage of the first sub-pixel to a target voltage; a first target level signal is generated on the basis of the size relationship between the target voltage and a preset voltage; and the first target level signal is outputted to the threshold circuit and the target voltage is outputted to the comparison circuit. The threshold circuit receives the first target level signal, then adjusts a second output voltage of the second sub-pixel to a threshold voltage and outputs the threshold voltage to the comparison circuit. The comparison circuit compares the target voltage with the threshold voltage, and then outputs a second target level signal. The present application can improve the robustness of determination during light intensity change.

Description

Image sensor, electronic device and system

[0001] This application claims priority to the Chinese patent application with application number 202410176159.2 filed with the State Intellectual Property Office of China on February 7, 2024, and priority to the Chinese patent application with the invention name “An image sensor, electronic device and system”, all contents of which are incorporated by reference into this application. Technical Field

[0002] The present application relates to the field of image processing technology, and in particular to an image sensor, electronic equipment, and system. Background Art

[0003] Image sensors typically output captured scenes frame by frame. Currently, "dynamic vision" technology for image sensors—that is, technology that enables image sensors to respond only to moving objects and not to stationary ones—has been applied in some applications. The basic method for implementing dynamic vision is to detect the change in incident light intensity captured by each pixel in the image sensor between two consecutive frames and compare it with a judgment threshold. Alternatively, the difference between the voltage output by each pixel at the current moment and the voltage at the next moment in the same frame is compared with the judgment threshold to determine the change in light intensity. If the change exceeds the judgment threshold, the incident light intensity is considered to have changed; if the change does not exceed the judgment threshold, the incident light intensity is considered to have remained unchanged. The judgment threshold is typically the relative change in the incident light intensity at the current moment, expressed as a percentage. For example, if the current incident light intensity is 500 lux and the judgment threshold is 20%, the comparison light intensities are 600 lux and 400 lux. 600 lux is used to determine whether the incident light intensity has increased, and 400 lux is used to determine whether the incident light intensity has decreased.

[0004] At present, when setting the judgment threshold, the influence of system noise (such as flicker noise of incident light, circuit noise, etc.) also needs to be considered. For example, when the incident light is small, the ratio of noise divided by signal is large, so the judgment threshold is usually set to a larger value; when the incident light intensity is large, the ratio of noise divided by signal is small, so the judgment threshold is usually set to a smaller value. Therefore, under normal circumstances, different pixels correspond to different incident light intensities, and different judgment thresholds will be used. However, in the current existing technology, the judgment thresholds corresponding to all pixels are the same, that is, different pixels in the same pixel array use the same judgment threshold regardless of whether the incident light is strong or small, which will lead to a decrease in judgment robustness or even misjudgment.

[0005] Therefore, how to improve the robustness of judgment when light intensity changes is a technical problem that needs to be solved urgently. Summary of the Invention

[0006] Embodiments of the present application provide an image sensor, an electronic device, and a system to improve the robustness of light intensity change judgment.

[0007] In a first aspect, an embodiment of the present application provides an image sensor comprising: a pixel array and a dynamic detection module; wherein the pixel array comprises a plurality of pixels, each pixel comprises at least a first sub-pixel and a second adjacent sub-pixel, and the exposure time of the first sub-pixel and the second sub-pixel in the same frame is different; the dynamic detection module comprises a light intensity contrast circuit, a threshold circuit and a comparison circuit; the light intensity contrast circuit is connected to the first sub-pixel, and is used to: receive a first output voltage of the first sub-pixel, and adjust the first output voltage to a target voltage; generate a first target level signal based on a magnitude relationship between the target voltage and a preset voltage, and the preset voltage is based on the light intensity The threshold circuit is connected to the second sub-pixel, and is used to: receive the second output voltage of the second sub-pixel, and adjust the second output voltage to the threshold voltage after receiving the first target level signal through the control terminal, wherein each of the pixels corresponds to its own threshold voltage; output the threshold voltage to the second input terminal of the comparison circuit; the comparison circuit is used to: compare the target voltage with the threshold voltage, and output the second target level signal based on the comparison result.

[0008] In the prior art, the judgment thresholds corresponding to all pixels in the image sensor are the same. In response to this, an embodiment of the present application provides an image sensor that can improve judgment robustness. The image sensor includes a pixel array and a dynamic detection module. The pixel array includes multiple pixels, each pixel including at least a first sub-pixel and a second sub-pixel with different exposure times. Furthermore, since the first sub-pixel and the second sub-pixel are adjacent in the pixel array, it can be approximately assumed that at any moment, the first sub-pixel and the second sub-pixel receive the same incident light intensity. Since the output of the pixel after exposure is proportional to the product of the exposure time and the incident light intensity, after obtaining the output voltages of the first sub-pixel and the second sub-pixel at different exposure times, the dynamic detection module can adjust the outputs at different exposure times to the outputs at the same exposure time and then compare them, thereby achieving detection of light intensity changes at different times within the same frame. Furthermore, compared to comparing the light intensity changes between the two frames in the digital domain, rapid light intensity detection can also be achieved in the analog domain. Furthermore, when detecting light intensity changes, the motion detection module can independently set the corresponding judgment threshold for each pixel based on the intensity of the incident light received by the sub-pixels within each pixel. This means that each pixel has its own corresponding threshold voltage. For example, a higher judgment threshold is set for pixels with low incident light intensity, while a lower judgment threshold is set for pixels with high incident light intensity. This independent setting of judgment thresholds for different pixels in the pixel array under the same environment improves the robustness of the judgment and mitigates the impact of noise on motion recognition.

[0009] In one possible implementation, the light intensity comparison circuit includes: a comparison circuit, the output end of the comparison circuit being the first output end of the light intensity comparison circuit; the comparison circuit is used to: generate the first target level signal based on the magnitude relationship between the target voltage and the preset voltage; and output the first target level signal to the control end of the threshold circuit.

[0010] In an embodiment of the present application, the light intensity comparison circuit in the dynamic detection module includes a comparison circuit, which can be used to compare the incident light intensity of the first sub-pixel during its exposure time with a preset light intensity, and output different first target level signals according to the comparison results. If the incident light intensity during the exposure time is greater than the preset light intensity, a first target level signal is generated to indicate that the incident light intensity is a strong incident light intensity; if the incident light intensity during the exposure time is less than the preset light intensity, a first target level signal is generated to indicate that the incident light intensity is a weak incident light intensity.

[0011] In one possible implementation, the first target level signal includes a first level signal and a second level signal, and the control end of the threshold circuit includes a first control end and a second control end; the comparison circuit includes a first comparator and a NOT gate; the first comparator is used to: receive the target voltage; compare the magnitude relationship between the target voltage and the preset voltage to generate the first level signal; output the first level signal to the first control end through the output end of the first comparator; the NOT gate is used to: receive the first level signal and output the second level signal to the second control end through the output end of the NOT gate.

[0012] In an embodiment of the present application, a comparison circuit can compare the incident light intensity with a preset light intensity using a comparator and a NOT gate. For example, a comparator compares the incident light intensity with the preset light intensity to output a first-level signal, which is then inverted by a NOT gate to output a second-level signal. These first-level and second-level signals can cooperate to control a threshold circuit to generate different threshold voltages, thereby setting a judgment threshold corresponding to each pixel, thereby improving the robustness of the judgment and adapting to the impact of noise on dynamic recognition.

[0013] In one possible implementation, the light intensity contrast circuit further includes: an adjustment circuit; the output end of the adjustment circuit is connected to the input end of the contrast circuit and serves as the second output end of the light intensity contrast circuit; the adjustment circuit is connected to the first sub-pixel and is used to: receive the first output voltage; adjust the first output voltage to the target voltage according to a proportional relationship between the exposure time corresponding to the first sub-pixel and the exposure time corresponding to the second sub-pixel; and output the target voltage to the first input end of the comparison circuit.

[0014] In an embodiment of the present application, the regulation circuit can amplify or reduce the output of sub-pixels with different exposure durations to achieve an equivalent output of sub-pixels with the same exposure duration. For example, based on the proportional relationship between the exposure duration corresponding to the first sub-pixel and the exposure duration corresponding to the second sub-pixel, the first output voltage is regulated to a target voltage, which is equivalent to the output of the first sub-pixel after being exposed to the exposure duration corresponding to the second sub-pixel. This regulation circuit can adjust the first sub-pixel to the same exposure duration as the second sub-pixel, thereby reducing errors caused by different exposure durations.

[0015] In one possible implementation, the threshold voltage includes a first threshold voltage and a second threshold voltage; the threshold circuit includes a first threshold sub-circuit and a second threshold sub-circuit, and both the first threshold sub-circuit and the second threshold sub-circuit include the first control terminal and the second control terminal; the first threshold sub-circuit is connected to the second sub-pixel, and is used to: receive the second output voltage, and after receiving the first level signal through the first control terminal and the second level signal through the second control terminal, adjust the second output voltage upward to the first threshold voltage; the second threshold sub-circuit is connected to the second sub-pixel, and is used to: receive the second output voltage, and after receiving the first level signal through the first control terminal and the second level signal through the second control terminal, adjust the second output voltage downward to the second threshold voltage; wherein the first threshold voltage is greater than the second threshold voltage.

[0016] In an embodiment of the present application, the threshold circuit includes a first threshold subcircuit and a second threshold subcircuit, the first threshold subcircuit is used to generate a first threshold voltage, the first threshold voltage can be used to determine whether the incident light intensity increases, and the second threshold subcircuit is used to generate a second threshold voltage, the first threshold voltage can be used to determine whether the incident light intensity decreases, and accordingly, the first threshold voltage is greater than the second threshold voltage. Moreover, when the first target level signal is different, the magnitude of the threshold voltage is also different. For example: when the first target level signal indicates that the incident light intensity is greater than the preset light intensity, the first threshold voltage and the second threshold voltage are smaller (i.e., low judgment threshold), and when the first target level signal indicates that the incident light intensity is less than the preset light intensity, the first threshold voltage and the second threshold voltage are larger (i.e., high judgment threshold). Different incident light intensities and the generation of different threshold voltages can enhance the robustness of the dynamic detection module's judgment.

[0017] In one possible implementation, the first threshold subcircuit includes a first capacitor, an op amp, a first switch tube, a second switch tube, a second capacitor, a third switch tube and a third capacitor; the ratio of the first capacitor to the second capacitor is different from the ratio of the first capacitor to the third capacitor; one end of the first capacitor is the input end of the first threshold subcircuit connected to the second sub-pixel, and the other end of the first capacitor is connected to the input end of the op amp; the first switch tube is connected between the input and output ends of the op amp; the second switch tube and the second capacitor are connected in series between the input and output ends of the op amp; the third switch tube and the third capacitor are connected in series between the input and output ends of the op amp; the output end of the op amp is the output end of the first threshold subcircuit connected to the second input end of the comparison circuit.

[0018] The first threshold subcircuit and the second threshold subcircuit have the same circuit structure, but their corresponding capacitors have different sizes so that they can generate different threshold voltages. In one embodiment of the present application, a simple circuit structure of the first threshold subcircuit is provided, in which the second output voltage can be adjusted to the first threshold voltage via an op amp. Furthermore, due to the different ratios between the second capacitor and the first capacitor and between the third capacitor and the first capacitor, the first threshold subcircuit can select different capacitors to conduct based on the first level signal and the second level signal, generating first threshold voltages of different sizes, thereby ensuring that each pixel corresponds to its own first threshold voltage.

[0019] In one possible implementation, the control end of the first switch tube is used to receive a control signal, and the control signal is used to control the first switch tube to turn on after the second sub-pixel starts to be exposed, and to turn off before the second sub-pixel completes exposure; the control end of the second switch tube is the first control end used to receive the first level signal, and the control end of the third switch tube is the second control end used to receive the second level signal.

[0020] In an embodiment of the present application, the control signal can cooperate with the first target level signal to control the first threshold subcircuit to generate a first threshold voltage so that the dynamic detection module can determine the change in incident light intensity corresponding to the pixel.

[0021] In one possible implementation, the second target level signal includes a third level signal and a fourth level signal; the comparison circuit is specifically used to: compare the target voltage with the first threshold voltage and output the third level signal; compare the target voltage with the second threshold voltage and output the fourth level signal.

[0022] In an embodiment of the present application, the comparison circuit needs to compare threshold voltages of different sizes and determine whether the incident light intensity of the corresponding pixel has changed based on the comparison result. For example, the target voltage is compared with the first threshold voltage to determine whether the incident light intensity of the corresponding pixel has become brighter or remained unchanged. The target voltage is compared with the second threshold voltage to determine whether the incident light intensity of the corresponding pixel has become darker or remained unchanged.

[0023] In one possible implementation, the comparison circuit includes a second comparator and a third comparator; the first input of the comparison circuit includes one input of the second comparator and one input of the third comparator; the second input of the comparison circuit includes another input of the second comparator and another input of the third comparator; one input of the second comparator is connected to the second output to receive the target voltage, the other input of the second comparator is connected to the output of the first threshold sub-circuit to receive the first threshold voltage, and the second comparator is used to output the third level signal; one input of the third comparator is connected to the second output to receive the target voltage; the other input of the third comparator is connected to the output of the second threshold sub-circuit to receive the second threshold voltage, and the third comparator is used to output the fourth level signal.

[0024] In the embodiment of the present application, the comparison circuit includes two comparators to respectively compare the target voltage with the first threshold voltage and the second threshold voltage.

[0025] In one possible implementation, when the third-level signal indicates that the target voltage is greater than the first threshold voltage, the brightness of the incident light intensity of the corresponding pixel changes from dark to bright; when the fourth-level signal indicates that the target voltage is less than the second threshold voltage, the brightness of the incident light intensity of the corresponding pixel changes from bright to dark; when the third-level signal and the fourth-level signal indicate that the target voltage is greater than the second threshold voltage and less than the first threshold voltage, the brightness of the incident light intensity of the corresponding pixel remains unchanged.

[0026] In the embodiment of the present application, the third level signal and the fourth level signal output by the comparison circuit can cooperate with each other to jointly indicate the change in the incident light intensity of the corresponding pixel.

[0027] In a second aspect, an embodiment of the present application provides an electronic device, comprising a circuit board and an image sensor provided by the first aspect or any possible implementation of the first aspect, wherein the circuit board is electrically connected to the image sensor.

[0028] In a third aspect, an embodiment of the present application provides a dynamic recognition system, which includes an image sensor provided by the above-mentioned first aspect or any possible implementation of the first aspect, and the image sensor is used for dynamic recognition.

[0029] It should be understood that the electronic device provided in the second aspect and the dynamic recognition system provided in the third aspect of this application are consistent with the technical solution of the first aspect of this application. Their specific contents and beneficial effects can be referred to the image sensor provided in the above-mentioned first aspect, and will not be repeated here. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the background technology, the drawings required for use in the embodiments of the present application or the background technology will be described below.

[0031] FIG1 is a schematic diagram of the relationship between incident light intensity and a judgment threshold value provided in an embodiment of the present application.

[0032] FIG2 is a schematic diagram of a dynamic visual result output by a frame difference method provided in an embodiment of the present application.

[0033] FIG3 is a schematic structural diagram of a pixel array provided in an embodiment of the present application.

[0034] FIG4 is a schematic diagram of a group of first sub-pixels and second sub-pixels provided in an embodiment of the present application.

[0035] FIG5 is a circuit diagram of a group of pixel structures provided in an embodiment of the present application.

[0036] FIG6A is a schematic diagram of control signals corresponding to a first sub-pixel and a second sub-pixel provided in an embodiment of the present application.

[0037] FIG6B is a schematic diagram of incident light intensity changes under a multi-frame image provided by an embodiment of the present application.

[0038] FIG7 is a schematic structural diagram of an image sensor provided in an embodiment of the present application.

[0039] FIG8A is a schematic structural diagram of a dynamic detection module provided in an embodiment of the present application.

[0040] FIG8B is a schematic diagram of a pixel array corresponding to a judgment threshold provided in an embodiment of the present application.

[0041] FIG9 is a schematic structural diagram of another dynamic detection module provided in an embodiment of the present application.

[0042] FIG10 is a circuit diagram of a light intensity contrast circuit provided in an embodiment of the present application.

[0043] FIG11A is a schematic structural diagram of another dynamic detection module provided in an embodiment of the present application.

[0044] FIG11B is a circuit diagram of a dynamic detection module provided in an embodiment of the present application.

[0045] FIG12 is a control timing diagram of a first threshold sub-circuit provided in an embodiment of the present application. DETAILED DESCRIPTION

[0046] The embodiments of the present application will be described below in conjunction with the drawings in the embodiments of the present application.

[0047] The terms "first," "second," "third," and "fourth," etc., in the specification and claims of this application and the accompanying drawings are used to distinguish between different objects, rather than to describe a specific order. In addition, the terms "including," "having," and any variations thereof, are intended to cover non-exclusive inclusions. For example, a process, method, system, product, or apparatus comprising a series of steps or elements is not limited to the listed steps or elements, but may optionally include steps or elements not listed, or may optionally include other steps or elements inherent to the process, method, product, or apparatus.

[0048] It should be understood that in this application, "at least one (item)" means one or more, and "plurality" means two or more. "And / or" is used to describe the association relationship of associated objects, indicating that three relationships may exist. For example, "A and / or B" can mean: only A exists, only B exists, and A and B exist at the same time, where A and B can be singular or plural. The character " / " generally indicates that the previous and next associated objects are in an "or" relationship. "At least one of the following items" or similar expressions refers to any combination of these items, including any combination of single items or plural items. For example, at least one of a, b or c can mean: a, b, c, "a and b", "a and c", "b and c", or "a and b and c", where a, b, c can be single or multiple.

[0049] For ease of description, embodiments of the present application may use spatial relationship terms such as "under", "below", "below", "below", "above", "on", etc. to describe the relationship between an element or feature shown in the drawings and other elements or features. It will be understood that these spatial relationship terms are intended to include other directions of the device in use or operation, in addition to the directions depicted in the drawings. For example, if the device in the drawings is turned over, the direction of the element described as "under" or "below" or "below" other elements or features will be changed to "above" the other elements or features. Thus, the exemplary terms "under" and "below" can include both the up and down directions. The device may also have other orientations (rotated 90 degrees or in other directions), so the spatial relationship descriptors used here should be interpreted accordingly. In addition, it will be understood that when a layer is referred to as being "between" two layers, it can be the only layer between the two layers, or there can be one or more layers between them.

[0050] References herein to "embodiments" mean that a particular feature, structure, or characteristic described in connection with the embodiments may be included in at least one embodiment of the present application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute an independent or alternative embodiment that is mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0051] As used in this specification, the terms "component," "module," "system," and the like are used to represent computer-related entities, hardware, firmware, a combination of hardware and software, software, or software in execution. For example, a component can be, but is not limited to, a process running on a processor, a processor, an object, an executable file, an execution thread, a program, and / or a computer. By way of illustration, both an application running on a computing device and a computing device can be a component. One or more components can reside in a process and / or an execution thread, and a component can be located on a computer and / or distributed between two or more computers. In addition, these components can be executed from various computer-readable media having various data structures stored thereon. Components can communicate, for example, via local and / or remote processes based on signals having one or more data packets (e.g., data from two components interacting with another component on a local system, a distributed system, and / or a network, such as the Internet interacting with other systems via signals).

[0052] First, in order to facilitate understanding of the embodiments of the present application, the technical problems that need to be solved by the embodiments of the present application are analyzed in detail below.

[0053] Generally speaking, image sensors can output the captured scene frame by frame. If most of the scene being captured (such as the background) is stationary and only certain objects are moving, the adjacent frames of images output by the image sensor will produce a lot of repeated and redundant information (for example, the background is stationary), which will increase a lot of redundant storage, calculation and power consumption. Moreover, in some application scenarios, moving objects are more worthy of attention. For example, in home monitoring, moving objects such as burglars, elderly people who accidentally fall, or moving pets are more worthy of attention than static objects such as sofas, tables and chairs in the background. Therefore, "Dynamic Vision" technology has developed accordingly.

[0054] Dynamic vision can also be called motion detection, event detection or brightness change detection. That is, the image sensor only responds to moving objects with changes in the incident light intensity, and does not respond to stationary objects. Therefore, when capturing key information, the image sensor can reduce the amount of calculation and power consumption of a large amount of meaningless information, making it easier to discover key information. Current dynamic vision technology is mainly divided into two types, one is dynamic vision detection based on dynamic vision sensor (DVS), and the other is dynamic vision detection based on the frame difference method of complementary metal oxide semiconductor image sensor (CIS).

[0055] When performing dynamic monitoring, DVS first obtains the difference between the voltage at the current moment and the voltage at the next moment. This difference is then fed into a comparator, where it is compared with two threshold voltages (ON / OFF) (the threshold voltages are determined by the judgment threshold). The comparator then outputs the dynamic visual judgment result, or "event." An event is defined as a change in the brightness of the incident light intensity, including "from dark to bright," "from bright to dark," and "no change in brightness." For example, if the ON threshold (i.e., the judgment threshold) is set to +20%, that is, the difference is greater than the ON threshold voltage corresponding to +20%, then the ON event is triggered, indicating that the incident light intensity at the next moment is 20% greater than the incident light intensity at the previous moment; if the OFF threshold (i.e., the judgment threshold) is set to -20%, that is, the difference is less than the OFF threshold voltage corresponding to -20%, then the OFF event is triggered, indicating that the incident light intensity at the next moment is 20% less than the incident light intensity at the previous moment; if the difference is within ±20%, that is, the difference is less than the ON threshold voltage and greater than the OFF threshold voltage, then the "brightness unchanged" event is triggered, indicating that the incident light intensity at the next moment is greater than the incident light intensity at the previous moment.

[0056] It should be noted that, please refer to Figure 1, which is a schematic diagram of the relationship between incident light intensity and judgment threshold provided by an embodiment of the present application. As shown in Figure 1, in order to reduce the impact of noise, the judgment threshold value in different environments is different according to the basic incident light intensity of the environment. The judgment threshold value is usually the relative change in the incident light intensity at the current moment, which is a percentage. For example, during the daytime when the incident light is strong, the ratio of noise to signal is small, and the judgment threshold value is set to a low threshold value, such as: the ON threshold value can be set to +10%, and the OFF threshold value is set to -10%; at night when the incident light is weak, the judgment threshold value is set to a high threshold value, such as: the ON threshold value can be set to +20% and the OFF threshold value is set to -20%. That is, when the incident light intensity is low, the ratio of noise to signal is large, and a high threshold value is set; when the incident light intensity is high, a low threshold value is set. Therefore, under normal circumstances, the ratio of noise to signal is different for different incident light intensities, and different judgment threshold values ​​will also be used.

[0057] The basic method used by the frame difference method to achieve dynamic vision is to detect the change in incident light intensity captured by each pixel in the image sensor between the previous and next moments. Specifically, if a pixel captures a stationary object, the incident light intensity remains unchanged between the previous and next moments. However, when a moving object passes by the pixel, the incident light intensity captured by the pixel changes, as the pixel captures the stationary object in the first moment and the moving object in the second moment. For example, a burglar wearing black clothing will typically have incident light intensity reflected by the pixel that is less than the background light intensity, making it visible to an image sensor with dynamic vision capabilities.

[0058] Regarding the dynamic visual detection of the frame difference method, please refer to Figure 2. Figure 2 is a schematic diagram of the dynamic visual result output by the frame difference method provided in an embodiment of the present application, as shown in (1) in Figure 2: CIS can output the images of frames 1 to 3 frame by frame. Compared with the image of frame 1, the image of frame 2 has an additional "pentagon"; compared with the image of frame 2, the image of frame 3 has an additional "square" and a "triangle". Therefore, the dynamic visual effect of the frame difference method should be as shown in (2) in Figure 2. This scheme makes a difference between the grayscale values ​​of the corresponding pixels of two adjacent frames to obtain the brightness changes at adjacent moments, and judges the moving object by the difference, that is, realizes the dynamic visual function.

[0059] However, the above two dynamic vision detection methods have at least the following disadvantages.

[0060] First, when DVS performs dynamic monitoring, the ON and OFF threshold voltages corresponding to all pixels in the pixel array are consistent and do not change due to differences in pixel location and the corresponding incident light intensity. That is, the judgment threshold for each pixel is consistent. However, in actual applications, pixels in the same pixel array may experience different incident light intensities due to their different locations. Furthermore, the above method compares the difference between the voltage output by each pixel at the current moment and the voltage at the next moment in the same frame with the judgment threshold to determine light intensity changes. Therefore, if all pixels are uniformly set to the ON and OFF thresholds, the accuracy of intensity change judgment will be low when the incident light intensity is low, and the sensitivity of intensity change judgment will be low when the incident light intensity is high. This will lead to reduced robustness in judging light intensity change events and may even lead to misjudgment of dynamic events due to noise.

[0061] Secondly, the frame difference method needs to compare the brightness changes of two adjacent frames when judging the changes in light intensity. Therefore, it is necessary to store the grayscale values ​​of all pixels in the previous frame, and then perform the difference on the corresponding pixels after the brightness value of the next frame is output. Therefore, the storage space is greatly increased, thereby increasing the chip area. In addition, since the frame difference method needs to compare the brightness changes of two adjacent frames, it is necessary to at least quantize the voltage value corresponding to the exposure through an analog-to-digital converter (ADC), that is, convert the analog signal into a digital signal (i.e., grayscale value) before comparison. Among them, the ADC conversion of each frame of the image takes a long time, so the time interval between two adjacent frames is large, that is, the time interval of the brightness information being compared is large, and it is impossible to achieve fast-changing light intensity detection.

[0062] Therefore, an embodiment of the present application provides an image sensor that can improve the robustness of judgment when performing rapid light intensity change detection. Exemplarily, the image sensor includes a pixel array and a dynamic detection module. The dynamic detection module can set a corresponding threshold for each pixel in the pixel array according to the actual magnitude of the incident light intensity received, that is, different pixels can correspond to different judgment thresholds in the same environment to improve the accuracy of the judgment of light intensity changes of pixels with smaller incident light intensity, and increase the sensitivity of the judgment of light intensity changes of pixels with larger incident light intensity, thereby improving the robustness of the pixel array for dynamic visual judgment within one frame to adapt to the impact of noise on dynamic recognition. In addition, by comparing the output voltages of two adjacent pixels in the same frame, the dynamic vision function is realized in the analog domain, which can realize the detection of rapidly changing light intensity, while reducing storage space and chip area. Among them, the specific structure and related description of the image sensor please refer to the following embodiments, which are not described in the embodiments of the present application.

[0063] Secondly, based on the technical issues raised above and to facilitate understanding of the embodiments of the present application, several pixel arrays on which the embodiments of the present application are based are described below.

[0064] The image sensor in the embodiments of the present application includes a pixel array and a dynamic detection module. The pixel array is used for exposure and photoelectric conversion, and the dynamic detection module is used for dynamic recognition based on the electrical signals output by the pixel array. The pixel array includes a plurality of pixels, each of which includes a plurality of sub-pixels, each of which includes at least a first sub-pixel and a second sub-pixel, the first sub-pixel and the second sub-pixel being adjacent to each other and corresponding to different exposure times. In other embodiments, the first sub-pixel and the second sub-pixel have filters of the same color.

[0065] Among them, the adjacent positions of the first sub-pixel and the second sub-pixel can be understood as two sub-pixels in adjacent rows of the same column, or two sub-pixels in adjacent columns of the same row, or two sub-pixels in adjacent rows and adjacent columns. For example, please refer to Figure 3, which is a structural schematic diagram of a group of pixel arrays provided in an embodiment of the present application. As shown in (1) in Figure 3, the pixel array may include 4 pixels, each pixel includes 4 sub-pixels, and all sub-pixels in each pixel correspond to the same color filter film. For example: the first pixel includes 4 sub-pixels of red filter film arranged in a matrix, and the pixel at least includes a first sub-pixel and a second sub-pixel that are adjacent in position. As shown in (2) and (3) in Figure 3, the sub-pixels in each pixel can correspond to filter films of different colors. At this time, the first sub-pixel and the second sub-pixel are two adjacent sub-pixels corresponding to the same color filter film in the pixel. As shown in (4) in Figure 3, in order to eliminate the influence of uneven light intensity, the first sub-pixel and the second sub-pixel can also be selected as two diagonally adjacent sub-pixels. As shown in (4) of FIG3 , due to the different structures of the pixel array itself, the first sub-pixel can be composed of at least two sub-pixels, and the second sub-pixel can also be composed of at least two sub-pixels. The multiple sub-pixels constituting the first sub-pixel can be exposed synchronously and together output a voltage after photoelectric conversion to constitute the output of the first sub-pixel; the multiple sub-pixels constituting the first sub-pixel can be exposed synchronously and together output a voltage after photoelectric conversion to constitute the output of the second sub-pixel.

[0066] Please refer to Figures 4 and 5. Figure 4 is a schematic diagram of a group of first sub-pixels and second sub-pixels provided in an embodiment of the present application, and Figure 5 is a circuit schematic diagram of a group of pixel structures provided in an embodiment of the present application. Depending on the structure of the pixel, the structure of the first sub-pixel and the second sub-pixel is also different. Taking a pixel including four sub-pixels of the same color filter film as an example, when the sub-pixels in each pixel are of the structure shown in (1) of Figure 5, that is, each sub-pixel has a separate source follower (SF) and row selector (RS), as shown in Figure 4, the first sub-pixel and the second sub-pixel can be a single sub-pixel. For example: the first sub-pixel is sub-pixel P2, and the second sub-pixel is sub-pixel P1; the first sub-pixel is sub-pixel P0, and the second sub-pixel is sub-pixel P3. When each pixel is of the structure shown in (2) of Figure 5, that is, all sub-pixels in the same pixel share the same source follower (SF) and row selector (RS), as shown in Figure 4, the first sub-pixel and the second sub-pixel can each include multiple sub-pixels. For example, the output of the first sub-pixel can be considered as the common output of sub-pixel P0 and sub-pixel P3, and the output of the second sub-pixel can be considered as the common output of sub-pixel P1 and sub-pixel P2. In other embodiments, the output of the first sub-pixel can also be considered as the common output of sub-pixel P0 and sub-pixel P1, and the output of the second sub-pixel can be considered as the common output of sub-pixel P2 and sub-pixel P3; or, the output of the first sub-pixel can also be considered as the common output of sub-pixel P0 and sub-pixel P2, and the output of the second sub-pixel can be considered as the common output of sub-pixel P1 and sub-pixel P3. This embodiment of the present application does not specifically limit this.

[0067] Taking the structure of the sub-pixel P0 shown in (1) of FIG5 as an example, the working principle of the sub-pixel is exemplified. Each sub-pixel can include a photodiode (Photodiode) P working under a reverse bias voltage and four transistors (4 transistors). The function of the photodiode is to convert incident photons into electrons (called "photogenerated electrons") and temporarily store them inside the photodiode. The four transistors include a reset tube (Reset Gate, RST), a charge transfer gate (Transmission Gate, TG), a source follower (Source Follower, SF) and a row selector (Row Selector, RS). For example: as shown in (1) of FIG5, the sub-pixel P0 may include RST0, TG0, SF0 and RS0. Among them, the source of RST0, the gate of SF0 and the drain of TG0 are connected to a floating diffusion potential (FD). When TG0 is turned on, the photogenerated electrons generated and temporarily stored in the photodiode are introduced into FD and stored, changing the voltage VFD at the FD point. The change in VFD is proportional to the product of the incident light intensity and the exposure time, thereby converting the incident light signal into a voltage signal. When reading the sub-pixel, RS0 is turned on, and VFD is output to the vertical signal line (VSL) through RS0, causing the voltage on VSL to change and be processed by the column line circuit. At this point, the sub-pixel completes the photoelectric conversion and voltage output. It should be noted that before the sub-pixel ends exposure, the reset voltage (V RST ), after the sub-pixel finishes exposure, the signal voltage (V SIG ), reset voltage (V RST ) and signal voltage (V SIG ) is proportional to the product of the incident light intensity and the exposure time.

[0068] In some embodiments, the exposure duration corresponding to the first sub-pixel in the same frame is different from the exposure duration corresponding to the second sub-pixel. Please refer to FIG6A, which is a schematic diagram of the control signals corresponding to the first sub-pixel and the second sub-pixel provided in an embodiment of the present application. As shown in (1) and (2) in FIG6A, the time interval between the two conductions of the TG tube of the first sub-pixel is the first exposure duration corresponding to the first sub-pixel, and the time interval between the two conductions of the TG tube of the second sub-pixel is the second exposure duration corresponding to the second sub-pixel. As shown in (1) in FIG6A, the first exposure duration is greater than the second exposure duration. As shown in (2) in FIG6A, the first exposure duration is less than the second exposure duration. It can be understood that in order to ensure that the exposure durations of the first sub-pixel and the second sub-pixel in the same frame are different, the exposure start time of the first sub-pixel and the second sub-pixel can be set to be different, and the exposure end time of the first sub-pixel and the second sub-pixel can be the same. In other embodiments, the exposure end time of the first sub-pixel and the second sub-pixel can be different.

[0069] Please refer to Figure 6B, which is a schematic diagram of incident light intensity variations under a multi-frame image according to an embodiment of the present application. As shown in Figure 6B, because the first and second sub-pixels have different exposure durations within the same frame, the dynamic visual output of each frame is a light intensity variation. For example, the incident light intensity of the nth frame changes from low to high. Compared to the frame difference method corresponding to Figure 2, which produces a dynamic visual effect with constant output light intensity, the different exposure durations of different pixels can capture rapidly changing light intensity variations, resulting in better dynamic visual detection.

[0070] It can be understood that if the sub-pixels included in the pixels in the pixel array are of the structure shown in (2) in FIG5 above, the control signals of the TG tubes corresponding to all sub-pixels in the first sub-pixel (such as sub-pixel P0 and sub-pixel P3) are consistent, that is, the start time and end time of exposure of all sub-pixels in the first sub-pixel are the same; the control signals of the TG tubes corresponding to all sub-pixels in the second sub-pixel (such as sub-pixel P1 and sub-pixel P2) are consistent, that is, the start time and end time of exposure of all sub-pixels in the second sub-pixel are the same; and the control signals of the TG tubes corresponding to the first sub-pixel (such as sub-pixel P0 and sub-pixel P3) and the second sub-pixel (such as sub-pixel P1 and sub-pixel P2) are different.

[0071] It can also be understood that the pixel arrays and the specific structures of the related pixels shown in the above embodiments are only a few exemplary implementations in the embodiments of the present application. The specific structures of the pixel arrays and the related pixels in the embodiments of the present application include but are not limited to the above structures.

[0072] Based on the above-mentioned pixel arrays, one of the image sensors based on the embodiments of the present application is described below.

[0073] Taking a pixel in a pixel array as an example, please refer to FIG7 , which is a schematic structural diagram of an image sensor provided in an embodiment of the present application.

[0074] As shown in FIG7 , the image sensor includes a pixel array and a dynamic detection module, and may also include a correlated double sampling (CDS), a programmable gain amplifier (PGA), and an analog-to-digital converter (ADC).

[0075] The pixel array includes multiple pixels, as shown in Figure 7. The sub-pixels in each pixel are connected to the corresponding CDS, PGA and ADC through the vertical signal column line VSL. The CDS can be used to obtain the output of the corresponding sub-pixel, that is, to collect the reset voltage (V RST ) and signal voltage (V SIG ), then the reset voltage (V RST ) and signal voltage (V SIG ) is the difference, that is, V RST -V SIG , eliminating most noise and making the difference proportional to the product of the incident light intensity and the exposure time. This difference is then input to the PGA, which linearly amplifies it to meet the ADC's input swing requirements. The ADC quantizes the amplified voltage and outputs the grayscale value of the corresponding pixel, converting the analog signal into a digital signal (grayscale value) for subsequent image generation.

[0076] The dynamic detection module can be connected to the first and second sub-pixels of the pixel, respectively, to receive the sub-pixel outputs to implement dynamic detection. In other embodiments, the dynamic detection module can also be connected to the output terminals of the CDS corresponding to the first and second sub-pixels, respectively, to directly receive the CDS outputs. Compared to comparing the light intensity changes between the previous and next frames in the digital domain, the dynamic detection module detects rapidly changing light intensities in the analog domain.

[0077] Specifically, please refer to FIG8A , which is a structural diagram of a dynamic detection module provided in an embodiment of the present application. As shown in FIG8A , the dynamic detection module may include a light intensity comparison circuit, a threshold circuit, and a comparison circuit.

[0078] The above-mentioned light intensity comparison circuit is connected to the above-mentioned first sub-pixel, and is used to: receive the first output voltage of the above-mentioned first sub-pixel, and adjust the above-mentioned first output voltage to a target voltage; generate a first target level signal based on the magnitude relationship between the above-mentioned target voltage and a preset voltage, and the above-mentioned preset voltage is a voltage set based on the light intensity; output the above-mentioned first target level signal to the control end of the above-mentioned threshold circuit through the first output end; and output the above-mentioned target voltage to the first input end of the above-mentioned comparison circuit through the second output end.

[0079] First, it should be noted that, as shown in FIG. 7 , since the first and second sub-pixels are spatially adjacent within the pixel, it can be approximately assumed that at any moment, the first and second sub-pixels receive the same incident light intensity. Furthermore, since the output of the sub-pixel after exposure is proportional to the product of the exposure duration and the incident light intensity, after obtaining the output voltages of the first and second sub-pixels at different exposure durations, the dynamic detection module adjusts the output of one sub-pixel to an exposure duration equivalent to that of the other sub-pixel, and then compares the output with the output of the other sub-pixel, thereby detecting light intensity changes at different moments within the same frame.

[0080] The light intensity comparison circuit needs to first adjust the output of the first sub-pixel to be equivalent to the output of the second sub-pixel before performing the comparison. That is, the first output voltage is adjusted to the target voltage to avoid the impact of different light intensities caused by different exposure times on dynamic recognition. Exemplarily, if the exposure time of the first sub-pixel is 0.5T and the exposure time of the second sub-pixel is T, the output of the first sub-pixel is multiplied by 2 so that the adjusted output is equivalent to the output of the first sub-pixel after exposure for a time of T. Another exemplary embodiment, if the exposure time of the first sub-pixel is 2T and the exposure time of the second sub-pixel is T, the output of the first sub-pixel is divided by 2 so that the adjusted output is equivalent to the output of the first sub-pixel after exposure for a time of T.

[0081] In addition, when performing light intensity change detection, the dynamic detection module can generate different level signals based on the magnitude of the incident light intensity received by the sub-pixels in each pixel, so that the threshold circuit generates a corresponding judgment threshold for the pixel. That is, the light intensity comparison circuit generates a first target level signal based on the magnitude relationship between the target voltage and the preset voltage, where the preset voltage is a voltage set based on the light intensity; and outputs the first target level signal to the control terminal of the threshold circuit via the first output terminal. For example, if the target voltage is greater than the preset voltage, it indicates that the incident light intensity of the first sub-pixel during the exposure time is greater than the preset light intensity, and a first target level signal is generated to indicate that the incident light intensity of the first sub-pixel is a strong incident light intensity; if the target voltage is less than the preset voltage, it indicates that the incident light intensity of the first sub-pixel during the exposure time is less than the preset light intensity, and a first target level signal is generated to indicate that the incident light intensity of the first sub-pixel is a weak incident light intensity. The first target level signal can be output to the control terminal of the threshold circuit via the first output terminal to control the threshold circuit to generate different threshold voltages. For example: for pixels that detect strong incident light intensity, a lower judgment threshold, ie, a low threshold voltage, is set; for pixels that detect weak incident light intensity, a higher judgment threshold, ie, a high threshold voltage, is set.

[0082] It is understandable that the above-mentioned preset voltage is a voltage preset based on the light intensity. For example, if 500 lux is set as the preset light intensity, the voltage corresponding to 500 lux is the preset voltage. When the target voltage is greater than the preset voltage, it means that the incident light intensity of the first sub-pixel is greater than 500 lux, which is a strong incident light intensity; when the target voltage is less than the preset voltage, it means that the incident light intensity of the first sub-pixel is less than 500 lux, which is a weak incident light intensity. Among them, the relevant modules or circuits for providing the preset voltage are not shown in the present application. The relevant modules or circuits for the preset voltage can be integrated into the dynamic detection module or can be set separately from the dynamic detection module. The embodiments of this application do not impose specific restrictions on this.

[0083] In other embodiments, multiple preset voltages may be set, each corresponding to a different light intensity. For example, two preset voltages may be set, one corresponding to a light intensity of 300 lux and the other corresponding to a light intensity of 600 lux. When the target voltage is less than the preset voltage corresponding to 300 lux, the incident light intensity of the first subpixel is less than 300 lux, indicating weak incident light intensity; when the target voltage is greater than the preset voltage corresponding to 600 lux, the incident light intensity of the first subpixel is greater than 600 lux, indicating strong incident light intensity; and when the target voltage is greater than the preset voltage corresponding to 300 lux and less than the preset voltage corresponding to 600 lux, the incident light intensity of the first subpixel is greater than 300 lux and less than 600 lux, indicating medium incident light intensity. Accordingly, the threshold circuit outputs different threshold voltages according to different incident light intensities. It will be understood that the embodiments of the present application do not specifically limit the number of preset voltages.

[0084] As shown in FIG8A , the threshold circuit is connected to the second sub-pixel and is also connected to the light intensity comparison circuit, and is configured to: receive the second output voltage of the second sub-pixel, and after receiving the first target level signal through the control terminal, adjust the second output voltage to a threshold voltage, wherein each of the pixels corresponds to its own threshold voltage; and output the threshold voltage to the second input terminal of the comparison circuit.

[0085] The threshold circuit can generate a threshold voltage corresponding to the pixel based on the second output voltage under the control of the first target level signal. For example, when the second output voltage is constant, the judgment threshold corresponding to the threshold voltage generated when the first target level signal indicates that the incident light intensity of the first sub-pixel is weak is greater than the judgment threshold corresponding to the threshold voltage generated when the first target level signal indicates that the incident light intensity of the first sub-pixel is strong. The magnitude of the judgment threshold refers to the magnitude of the increase or decrease based on the first output voltage. For example, setting a lower judgment threshold, i.e., a low threshold voltage, means increasing or decreasing the second output voltage by 10%; setting a higher judgment threshold, i.e., a high threshold voltage, means increasing or decreasing the second output voltage by 20%. This method of setting corresponding judgment thresholds for different pixels in the pixel array under the same environment makes each pixel independent of each other, which can improve the robustness of dynamic visual judgment.

[0086] It can be understood that, please refer to FIG8B, FIG8B is a schematic diagram of a pixel array corresponding to a judgment threshold provided by an embodiment of the present application. As shown in FIG8B (1), the incident light intensity of each pixel in the pixel array is different. As shown in FIG8B (2), each pixel in the pixel array in the prior art has a unified judgment threshold, that is, all pixels uniformly correspond to a high judgment threshold, or all pixels uniformly correspond to a low judgment threshold. As shown in FIG8B (3), based on the incident light intensity as shown in FIG8B (1), a pixel in the pixel array that detects a low incident light intensity can be set to a higher judgment threshold; a pixel that detects a strong incident light can be set to a lower judgment threshold. In this way, different pixels in the pixel array are set with their own corresponding judgment thresholds under the same environment, and each pixel is independent of each other, thereby improving the accuracy of judgment when the incident light intensity is small, and improving the sensitivity of judgment when the incident light intensity is large, thereby improving the robustness of judgment and adapting to the influence of noise on dynamic recognition.

[0087] As shown in FIG8A , the comparison circuit is connected to the threshold circuit and the light intensity comparison circuit, respectively, and is configured to compare the target voltage with the threshold voltage and output a second target level signal based on the comparison result. It will be appreciated that the comparison circuit compares the target voltage with the threshold voltage, obtains a comparison result, and outputs a second target level signal indicating the comparison result. Since the threshold voltage is obtained by increasing or decreasing the second output voltage, by comparing the target voltage with the threshold voltage, it is possible to determine whether the light intensity change corresponding to the pixel exceeds the judgment threshold, thereby achieving dynamic visual detection. This approach, by comparing the output voltages of two adjacent pixels within the same frame, implements dynamic visual functions in the analog domain, enabling detection of rapidly changing light intensities while reducing storage space and chip area.

[0088] In addition, in some embodiments, the above-mentioned light intensity comparison circuit includes: a comparison circuit, the output end of the above-mentioned comparison circuit is the above-mentioned first output end of the above-mentioned light intensity comparison circuit; the above-mentioned comparison circuit is used to: generate the above-mentioned first target level signal based on the size relationship between the above-mentioned target voltage and the above-mentioned preset voltage; and output the above-mentioned first target level signal to the control end of the above-mentioned threshold circuit.

[0089] Please refer to Figure 9, which is a schematic diagram of the structure of another dynamic detection module provided in an embodiment of the present application. As shown in Figure 9, the light intensity comparison circuit in the dynamic detection module includes a comparison circuit, the output terminal of which is the first output terminal of the light intensity ratio circuit described above. The comparison circuit can be used to compare the incident light intensity of the first sub-pixel during its exposure time with the preset light intensity, that is, to compare the target voltage with the preset voltage, and output different first target level signals to the control terminal of the threshold circuit based on the comparison result.

[0090] In some embodiments, the first target level signal includes a first level signal and a second level signal, and the control end of the threshold circuit includes a first control end and a second control end; the comparison circuit includes a first comparator and a NOT gate; the first comparator is used to: receive the target voltage; compare the target voltage with the preset voltage to generate the first level signal; output the first level signal to the first control end through the output end of the first comparator; the NOT gate is used to: receive the first level signal and output the second level signal to the second control end through the output end of the NOT gate.

[0091] Taking the preset voltage as an example, please refer to Figure 10, which is a circuit diagram of a light intensity comparison circuit provided by an embodiment of the present application. As shown in Figure 10, the light intensity comparison circuit in the dynamic detection module includes a comparison circuit, which includes a first comparator CMP1 and a NOT gate NOT. The first comparator CMP1 includes two input terminals, one of which receives a target voltage V A , the other input terminal receives the preset voltage V B , the preset voltage V B The voltage is preset based on the light intensity.

[0092] The first comparator CMP1 can compare the target voltage V A With the preset voltage V B The magnitude relationship between them is output to the first control terminal, and the corresponding first level signal V1 is output to the second control terminal after being inverted by the NOT gate NOT. A Greater than the preset voltage V B When the target voltage V A Less than the preset voltage V B When the pixel is detected, a low-level signal can be output to the NOT gate. This low-level signal is converted to a high-level signal after passing through the NOT gate, indicating that the incident light intensity corresponding to the pixel is weak. The first level signal V1 and the second level signal V2 can cooperate with each other to control the threshold circuit to generate threshold voltages of different sizes, thereby improving the robustness of the judgment and adapting to the impact of noise on dynamic recognition.

[0093] In some embodiments, the light intensity contrast circuit further includes: an adjustment circuit; the output end of the adjustment circuit is connected to the input end of the contrast circuit and serves as the second output end of the light intensity contrast circuit; the adjustment circuit is connected to the first sub-pixel and is used to: receive the first output voltage; adjust the first output voltage to the target voltage according to the proportional relationship between the exposure time corresponding to the first sub-pixel and the exposure time corresponding to the second sub-pixel; and output the target voltage to the first input end of the comparison circuit.

[0094] The regulating circuit is connected to the above-mentioned contrast circuit, the first sub-pixel and the comparison circuit. Among them, the input end of the regulating circuit is connected to the output of the first sub-pixel, the output end of the regulating circuit is connected to the input of the above-mentioned contrast circuit, and the second output end of the light intensity contrast circuit is connected to the comparison circuit. The regulating circuit can amplify or reduce the sub-pixel outputs of different exposure times to adjust them to sub-pixel outputs with equivalent same exposure times. For example: receive the above-mentioned first output voltage; and according to the proportional relationship between the exposure time corresponding to the first sub-pixel and the exposure time corresponding to the second sub-pixel, adjust the above-mentioned first output voltage to the target voltage, which is equivalent to the output of the first sub-pixel after being exposed according to the exposure time corresponding to the second sub-pixel. Exemplarily, the exposure time corresponding to the first sub-pixel is 0.5T and the exposure time corresponding to the second sub-pixel is T, then the proportional relationship between the exposure time corresponding to the first sub-pixel and the exposure time corresponding to the second sub-pixel is 2, and accordingly, the regulating circuit can adjust the first output voltage V P1 Expanded to twice, so that the exposure time of the first sub-pixel is equivalently adjusted to the same exposure time as the second sub-pixel, so as to reduce the error caused by the different exposure times. P1 Including the reset voltage of the first sub-pixel (V RST1 ) and signal voltage (V SIG1 ), its reset voltage (V RST1 ) and signal voltage (V SIG1 ) (i.e. V RST1 -V SIG1 ) is proportional to the product of the incident light intensity of the first sub-pixel and the exposure time.

[0095] As shown in FIG10 , a circuit structure of a regulating circuit is also exemplarily provided. The regulating circuit may include a fourth capacitor C7, an operational amplifier OP3, a fourth switch transistor T4, a fifth switch transistor T5, and a second capacitor C8. One end of the fourth capacitor C7 is connected to the first sub-pixel as the input end of the regulating circuit and receives the first output voltage V P1The other end of the fourth capacitor C7 is connected to an input end of the operational amplifier OP3; the fourth switch tube T4 is connected between the above-mentioned one input end and the output end of the operational amplifier OP3; the fifth switch tube T5 and the second capacitor C8 are connected in series between the above-mentioned one input end and the output end of the operational amplifier OP3; the output end of the operational amplifier OP3 is the output end of the regulating circuit and is connected to the input end of the comparison circuit, wherein the other input end of the operational amplifier OP3 is connected to the voltage V REF , for example, the voltage V REF Equal to 0.5VDD, this embodiment of the present application does not make any specific limitation on this. According to the operating principle of the regulation circuit, the V A =V REF +C7 / C8×(V RST1 -V SIG1 ), therefore, when the exposure duration corresponding to the first sub-pixel is twice that corresponding to the exposure duration corresponding to the second sub-pixel, the corresponding C7 / C8 = 0.5; when the exposure duration corresponding to the first sub-pixel is 0.5 times that corresponding to the exposure duration corresponding to the second sub-pixel, the corresponding C7 / C8 = 2. Furthermore, the specific operating principle of the adjustment circuit can be referred to in the following description of the operating principle of the first threshold sub-circuit, which will not be elaborated here. It should be noted that the second capacitor C8 in the adjustment circuit can be an adjustable capacitor, that is, the capacitance value of the second capacitor C8 is variable.

[0096] In some embodiments, the threshold voltage includes a first threshold voltage and a second threshold voltage, wherein the first threshold voltage is greater than the second threshold voltage. It is understood that the first threshold voltage may be an ON threshold voltage corresponding to triggering an ON event, and the second threshold voltage may be an OFF threshold voltage corresponding to triggering an OFF event.

[0097] The threshold circuit includes a first threshold subcircuit and a second threshold subcircuit, each of which includes the first control terminal and the second control terminal. The first threshold subcircuit is connected to the second subpixel and is configured to receive the second output voltage and, upon receiving the first level signal via the first control terminal and the second level signal via the second control terminal, adjust the second output voltage upward to a first threshold voltage. The second threshold subcircuit is connected to the second subpixel and is configured to receive the second output voltage and, upon receiving the first level signal via the first control terminal and the second level signal via the second control terminal, adjust the second output voltage downward to a second threshold voltage.

[0098] Please refer to Figures 11A and 11B. Figure 11A is a schematic diagram of the structure of another dynamic detection module provided in an embodiment of the present application, and Figure 11B is a circuit diagram of a dynamic detection module provided in an embodiment of the present application. As shown in Figure 11A, the threshold circuit includes a first threshold subcircuit and a second threshold subcircuit. The first threshold subcircuit includes a first control terminal G1 and a second control terminal G2, which are used to receive a first level signal and a second level signal to generate a first threshold voltage. The first threshold voltage can be used to determine whether the incident light intensity has increased. The second threshold subcircuit also includes a first control terminal G1 and a second control terminal G2, which are used to receive a first level signal and a second level signal to generate a second threshold voltage. The first threshold voltage can be used to determine whether the incident light intensity has increased, and the second threshold voltage can be used to determine whether the incident light intensity has decreased.

[0099] Furthermore, when the first target level signal is different, that is, when the first level signal and the second level signal are different, the magnitude of the threshold voltage is also different. For example, when the first target level signal indicates that the incident light intensity is greater than the preset light intensity, that is, according to the circuit structure shown in FIG11B above, the first level signal is a high level signal and the second level signal is a low level signal, the first threshold voltage and the second threshold voltage can be threshold voltages corresponding to the low judgment threshold. Exemplarily, the low judgment threshold can be ±10%. When the first target level signal indicates that the incident light intensity is less than the preset light intensity, that is, according to the circuit structure shown in FIG11B above, the first level signal is a low level signal and the second level signal is a high level signal, the first threshold voltage and the second threshold voltage can be threshold voltages corresponding to the high judgment threshold. Exemplarily, the high judgment threshold can be ±20%. Generating different threshold voltages according to different incident light intensities can enhance the robustness of the dynamic detection module's judgment.

[0100] In some embodiments, as shown in FIG11B , the first threshold subcircuit includes a first capacitor C1, an op amp OP1, a first switch T1, a second switch T2, a second capacitor C2, a third switch T3, and a third capacitor C3. One end of the first capacitor C1 is the input end of the first threshold subcircuit connected to the output of the second subpixel to receive the second output voltage V P2 The other end of the first capacitor C1 is connected to an input end of the operational amplifier OP1; the first switch tube T1 is connected between the input end and the output end of the operational amplifier OP1; the second switch tube T2 and the second capacitor C2 are connected in series between the input end and the output end of the operational amplifier OP1; the third switch tube T3 and the third capacitor C3 are connected in series between the input end and the output end of the operational amplifier OP1; the output end of the operational amplifier OP1 is the output end of the first threshold sub-circuit, connected to the second input end of the comparison circuit, and outputs a first threshold voltage V to the comparison circuit.ON In addition, the other input terminal of the op amp OP1 can be connected to the power supply voltage V REF . According to the relevant description of FIG5(1) above, the second output voltage V P2 Including the reset voltage of the second sub-pixel (V RST2 ) and signal voltage (V SIG2 ), the reset voltage of the second sub-pixel (V RST2 ) and signal voltage (V SIG2 ) (i.e. V RST2 -V SIG2 ) is proportional to the product of the incident light intensity of the second sub-pixel and the exposure time.

[0101] The ratio of the first capacitor C1 to the second capacitor C2 is different from the ratio of the first capacitor C1 to the third capacitor C3. In other embodiments, the second capacitor C2 and the third capacitor C3 are adjustable capacitors, that is, the capacitance values ​​of the second capacitor C2 and the third capacitor C3 are variable, which is not specifically changed in the embodiments of the present application.

[0102] From the above circuit structure, it can be seen that the first threshold sub-circuit can use the op amp to convert the second output voltage V P2 Adjust to the first threshold voltage V ON Moreover, since the ratio between the second capacitor C2 and the first capacitor C1 in the first threshold sub-circuit is different from the ratio between the third capacitor C3 and the first capacitor C1, the first threshold sub-circuit can select different capacitors to be turned on based on the first level signal V1 and the second level signal V2, thereby generating first threshold voltages of different sizes, so that each pixel corresponds to its own first threshold voltage.

[0103] In some embodiments, the control end of the first switch tube T1 in the first threshold sub-circuit is used to receive a control signal AZ1, and the control signal AZ1 is used to control the first switch tube T1 to turn on after the second sub-pixel starts to be exposed, and to turn off before the second sub-pixel completes exposure; the control end of the second switch tube T2 is the first control end for receiving the first level signal V1, and the control end of the third switch tube T3 is the second control end for receiving the second level signal V2.

[0104] For example, when the first level signal V1 is a high level signal, the second switch tube T2 is controlled to remain on; and the second level signal V2 is a low level signal, the third switch tube T3 is controlled to remain off, please refer to FIG12, which is a control timing diagram of a first threshold sub-circuit provided by an embodiment of the present application. As shown in FIG12, the first pass control signal AZ1 turns on the first switch tube T1, so that the input and output of the operational amplifier OP1 are short-circuited. At this time, the output of the operational amplifier OP1 (that is, the first threshold voltage VON )V OUT1 =V REF At this time, the input voltage of the op amp OP1 is the reset voltage V RST2 Then the control signal AZ1 turns off the first switch tube T1. After the exposure is completed, the output of the second sub-pixel changes from V RST2 becomes V SIG2 , that is, the input voltage of the op amp OP1 changes from V RST2 becomes V SIG2 According to the basic working principle of the circuit, the output of the operational amplifier OP1 (ie, the first threshold voltage V ON )V OUT1 =V REF +C1 / C2×(V RST2 -V SIG2 ), where (V RST2 -V SIG2 ) can be considered as the second output voltage V P2 , the corresponding C1 / C2 can be considered as the judgment threshold corresponding to the first threshold sub-circuit.

[0105] It can be understood that when the first level signal V1 is a low level signal, the second switch tube T2 is controlled to remain off; when the second level signal V2 is a high level signal, the third switch tube T3 is controlled to remain on, at this time, the output V OUT1 =V REF +C1 / C3×(V RST2 -V SIG2 Therefore, when the ratio between the second capacitor C2 and the first capacitor C1 is different from the ratio between the third capacitor C3 and the first capacitor C1, the first level signal V1 and the second level signal V2 select different capacitors to be turned on, so as to control the first threshold sub-circuit to generate first threshold voltages of different magnitudes.

[0106] For example, when C1 / C2=1.1 and C1 / C3=1.2, under the condition of high incident light intensity, the first level signal V1 and the second level signal V2 control the second switch tube T2 to remain on and the third switch tube T3 to remain off, so that the ON threshold generated by the first threshold sub-circuit is set to the low judgment threshold + 10%, and the first threshold voltage V ON =V OUT1 =V REF +C1 / C2×(V RST2 -V SIG2 ). Accordingly, when the incident light intensity is low, the first level signal V1 and the second level signal V2 control the second switch tube T2 to remain off, and the third switch tube T3 to remain on, so that the first threshold sub-circuit generates an ON threshold value set to the high judgment threshold value + 20%, and the first threshold voltage V ON=V OUT1 =V REF +C1 / C3×(V RST2 -V SIG2 ), thereby generating first threshold voltages corresponding to different judgment thresholds according to the light intensity, so as to adapt to the influence of noise and improve the robustness of judgment.

[0107] The first threshold sub-circuit and the second threshold sub-circuit have the same circuit structure, but their corresponding capacitors have different sizes, so that they respectively generate threshold voltages of different sizes.

[0108] Correspondingly, as shown in FIG11B , the second threshold subcircuit is consistent with the first threshold subcircuit and also includes a first capacitor C4, an op amp OP2, a first switch T1, a second switch T2, a second capacitor C5, a third switch T3, and a third capacitor C6. One end of the first capacitor C4 serves as the input of the second threshold subcircuit and is connected to the second sub-pixel, while the other end of the first capacitor C4 is connected to the input of the op amp OP2. The first switch T1 is connected between the input and output of the op amp OP2. The second switch T2 and the second capacitor C5 are connected in series between the input and output of the op amp OP2. The third switch T3 and the third capacitor C6 are connected in series between the input and output of the op amp OP2. The output of the op amp OP2 serves as the output of the second threshold subcircuit and is connected to the second input of the comparison circuit.

[0109] The control end of the first switch tube T1 in the second threshold sub-circuit is used to receive a control signal AZ2. The control signal AZ2 is used to control the first switch tube T1 to turn on after the second sub-pixel starts to be exposed, and to turn off before the second sub-pixel completes exposure. The control end of the second switch tube T2 is the first control end for receiving the first level signal V1, and the control end of the third switch tube T3 is the second control end for receiving the second level signal V2.

[0110] It is understandable that the ratio of the first capacitor C4 to the second capacitor C5 is different from the ratio of the first capacitor C4 to the third capacitor C5. Furthermore, because the first threshold voltage is greater than the second threshold voltage, the ratio of the first capacitor C1 to the second capacitor C2, as well as the ratio of the first capacitor C1 to the third capacitor C3, in the first threshold subcircuit are both greater than 1, while the ratio of the first capacitor C4 to the second capacitor C5, as well as the ratio of the first capacitor C4 to the third capacitor C5, in the second threshold subcircuit are both less than 1.

[0111] For example, when C4 / C5=0.9 and C4 / C6=0.8, under the condition of high incident light intensity, the first level signal V1 and the second level signal V2 control the second switch tube T2 to remain on and the third switch tube T3 to remain off, so that the OFF threshold generated by the second threshold subcircuit is set to the low judgment threshold -10%, and the second threshold voltage V OFF =V OUT2 =V REF +C4 / C5×(V RST2 -V SIG2 ). Accordingly, when the incident light intensity is small, the first level signal V1 and the second level signal V2 control the second switch tube T2 to remain off, and the third switch tube T3 to remain on, so that the first threshold sub-circuit generates an OFF threshold value set to the high judgment threshold value -20%, and the second threshold voltage V OFF =V OUT2 =V REF +C4 / C6×(V RST2 -V SIG2 ), thereby generating a second threshold voltage corresponding to a different judgment threshold according to the light intensity, so as to adapt to the influence of noise and improve the robustness of the judgment.

[0112] It can also be understood that the first level signal V1 and the second level signal V2 cooperate with the first threshold sub-circuit and the second threshold sub-circuit so that when the incident light intensity is a strong incident light intensity, a threshold voltage corresponding to a low judgment threshold is generated, and when the incident light intensity is a weak incident light intensity, a threshold voltage corresponding to a high judgment threshold is generated. Therefore, the embodiment of the present application does not make specific limitations on the ratio relationship between the various capacitors in the first threshold sub-circuit and the second threshold sub-circuit.

[0113] In some embodiments, the second target level signal includes a third level signal and a fourth level signal; the comparison circuit is specifically configured to: compare the target voltage with the first threshold voltage to output a third level signal; and compare the target voltage with the second threshold voltage to output a fourth level signal. The comparison circuit may compare threshold voltages of different magnitudes and, based on the comparison results corresponding to the threshold voltages of different magnitudes, determine whether the incident light intensity of the corresponding pixel has changed. For example, the comparison circuit may compare the target voltage with the first threshold voltage to determine whether the incident light intensity of the corresponding pixel has become brighter or remained unchanged, and may compare the target voltage with the second threshold voltage to determine whether the incident light intensity of the corresponding pixel has become darker or remained unchanged.

[0114] In some embodiments, the comparison circuit includes a second comparator and a third comparator. As shown in FIG11B , the comparison circuit includes a second comparator CMP2 and a third comparator CMP3. One input terminal of the second comparator CMP2 and one input terminal of the third comparator CMP3 together constitute a first input terminal of the comparison circuit, and together receive the target voltage V output by the second output terminal of the light intensity comparison circuit. A The other input terminal of the second comparator CMP2 and the other input terminal of the third comparator CMP3 together constitute the second input terminal of the comparison circuit, wherein the other input terminal of the second comparator CMP2 is connected to the output terminal of the first threshold sub-circuit to receive the first threshold voltage V ON The other input terminal of the third comparator CMP3 is connected to the output terminal of the second threshold sub-circuit to receive the second threshold voltage V OFF The second comparator CMP2 is used to output the third level signal V3; the third comparator CMP3 is used to output the fourth level signal V4. The two comparators of the comparison circuit can compare the target voltage V A With the first threshold voltage V ON and the second threshold voltage V OFF The size relationship between them can be used to quickly detect rapid changes in the incident light intensity.

[0115] In some embodiments, when the third level signal indicates that the target voltage is greater than the first threshold voltage, the brightness of the incident light intensity of the corresponding pixel changes from dark to bright; when the fourth level signal indicates that the target voltage is less than the second threshold voltage, the brightness of the incident light intensity of the corresponding pixel changes from bright to dark; when the third level signal and the fourth level signal indicate that the target voltage is greater than the second threshold voltage and less than the first threshold voltage, the brightness of the incident light intensity of the corresponding pixel remains unchanged.

[0116] Taking the circuit structure shown in FIG. 11B as an example, when the target voltage V A Greater than the first threshold voltage V ON When the first threshold voltage V ON Greater than the second threshold voltage V OFF Therefore, the third level signal V3 and the fourth level signal V4 are both high level, that is, the second comparator CMP2 outputs "1", and the third comparator CMP3 outputs "1", that is, the comparison circuit outputs 11, representing that the pixel triggers an ON event, indicating that the brightness of the incident light intensity changes from dark to bright. When the target voltage V A is less than the second threshold voltage V OFFWhen the target voltage V A Less than the first threshold voltage V ON and is greater than the second threshold voltage V OFF , and since the first threshold voltage V ON Greater than the second threshold voltage V OFF Therefore, both the third-level signal V3 and the fourth-level signal V4 are high. That is, the second comparator CMP2 outputs "1," and the third comparator CMP3 outputs "1." In other words, the comparison circuit outputs 01, indicating that the pixel has triggered a "brightness unchanged" event, indicating that the brightness change of the incident light intensity is unchanged. The third-level signal and the fourth-level signal output by the comparison circuit can cooperate with each other to jointly indicate the change in the incident light intensity of the corresponding pixel.

[0117] In summary, embodiments of the present application provide an image sensor that can improve the robustness of judgment when detecting rapid light intensity changes. The image sensor includes a pixel array and a dynamic detection module. The pixel array includes multiple pixels, each pixel including at least a first sub-pixel and a second sub-pixel with different exposure times within the same frame. Furthermore, since the first and second sub-pixels are adjacent in the pixel array, it can be approximately assumed that at any moment, the first and second sub-pixels receive the same incident light intensity. Since the output of a pixel after exposure is proportional to the product of the exposure time and the incident light intensity, after obtaining the output voltages of the first and second sub-pixels at different exposure times, the dynamic detection module can adjust the outputs at different exposure times to the outputs at the same exposure time and then compare them, thereby detecting light intensity changes at different times within the same frame, thereby achieving dynamic visual detection. Furthermore, compared to comparing light intensity changes between two frames in the digital domain, the image sensor of embodiments of the present application can detect rapidly changing light intensity within the same frame based on the analog domain. Compared to comparing the time interval between two adjacent frames, the time required to detect light intensity changes is greatly shortened, thereby achieving rapid light intensity detection. Furthermore, and most importantly, when detecting light intensity changes, the image sensor's dynamic detection module can independently set the corresponding judgment threshold for each pixel based on the intensity of the incident light received by the pixel. That is, each pixel corresponds to its own threshold voltage. For example, a higher judgment threshold is set for pixels detecting low incident light intensity, while a lower judgment threshold is set for pixels detecting high incident light intensity. This method sets corresponding judgment thresholds for different pixels in the pixel array under the same environment, making each pixel independent of each other. This increases the accuracy of judgments when the incident light intensity is low and improves the sensitivity of judgments when the incident light intensity is high, thereby improving the robustness of judgments and adapting to the impact of noise on dynamic recognition.

[0118] The present application also provides an electronic device comprising a circuit board and an image sensor according to the embodiments shown in Figures 3-12 above, wherein the circuit board is electrically connected to the image sensor. The electronic device can detect changes in light intensity through the image sensor to achieve dynamic visual detection.

[0119] An embodiment of the present application further provides a dynamic recognition system, which includes an image sensor. The image sensor may be the image sensor involved in the relevant embodiments shown in FIG. 3 to FIG. 12 .

[0120] It should be understood that the electronic device or dynamic recognition system provided in the embodiments of the present application is consistent with the image sensor involved in the relevant embodiments shown in Figures 3 to 12 above. Its specific content and beneficial effects can be referred to the image sensor involved in the relevant embodiments shown in Figures 3 to 12 above, and will not be repeated here.

[0121] In the above embodiments, the description of each embodiment has its own focus. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0122] It should be noted that for the aforementioned method embodiments, for the sake of simplicity, they are all expressed as a series of action combinations, but those skilled in the art should be aware that this application is not limited by the order of the actions described, because according to this application, certain steps may be performed in other orders or simultaneously. Secondly, those skilled in the art should also be aware that the embodiments described in this specification are all preferred embodiments, and the actions and modules involved are not necessarily required by this application.

[0123] In the several embodiments provided in this application, it should be understood that the disclosed devices can be implemented in other ways. For example, the device embodiments described above are merely illustrative. For example, the division of the above-mentioned units is only a logical function division. In actual implementation, there may be other division methods, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, and the indirect coupling or communication connection of devices or units can be electrical or other forms.

[0124] The units described above as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed across multiple network units. Some or all of these units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0125] In addition, the functional units in the embodiments of the present application may be integrated into a single processing unit, or each unit may exist physically separately, or two or more units may be integrated into a single unit. The aforementioned integrated units may be implemented in the form of hardware or software functional units.

[0126] If the above-mentioned integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application is essentially or the part that contributes to the prior art or all or part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including a number of instructions for enabling a computer device (which can be a personal computer, a server or a network device, etc., specifically a processor in a computer device) to execute all or part of the steps of the above-mentioned methods of each embodiment of the present application. Among them, the aforementioned storage medium may include: U disk, mobile hard disk, magnetic disk, optical disk, read-only memory (Read-Only Memory, abbreviated: ROM) or random access memory (Random Access Memory, abbreviated: RAM) and other media that can store program codes.

[0127] As described above, the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the above embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the above embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. An image sensor, characterized in that: include: A pixel array and a dynamic detection module; wherein the pixel array includes a plurality of pixels, each pixel includes at least a first sub-pixel and a second adjacent sub-pixel, and the exposure time of the first sub-pixel and the second sub-pixel in the same frame is different; The dynamic detection module includes a light intensity comparison circuit, a threshold circuit and a comparison circuit; The light intensity comparison circuit is connected to the first sub-pixel and is configured to: receive a first output voltage of the first sub-pixel, adjust the first output voltage to a target voltage; generate a first target level signal based on a magnitude relationship between the target voltage and a preset voltage, where the preset voltage is a voltage set based on light intensity; output the first target level signal to the control terminal of the threshold circuit via a first output terminal; and output the target voltage to the first input terminal of the comparison circuit via a second output terminal. The threshold circuit is connected to the second sub-pixel and is configured to: receive a second output voltage of the second sub-pixel and, after receiving the first target level signal through the control terminal, adjust the second output voltage to a threshold voltage, wherein each pixel corresponds to its own threshold voltage; and output the threshold voltage to the second input terminal of the comparison circuit; The comparison circuit is configured to compare the target voltage with the threshold voltage and output a second target level signal based on a comparison result.

2. The image sensor according to claim 1, wherein: The light intensity contrast circuit comprises: a contrast circuit, wherein the output end of the contrast circuit is the first output end of the light intensity contrast circuit; The comparison circuit is configured to generate the first target level signal based on a magnitude relationship between the target voltage and the preset voltage; The first target level signal is output to the control terminal of the threshold circuit.

3. The image sensor according to claim 2, wherein: The first target level signal includes a first level signal and a second level signal, and the control end of the threshold circuit includes a first control end and a second control end; The comparison circuit includes a first comparator and a NOT gate; The first comparator is configured to: receive the target voltage; compare the target voltage with the preset voltage to generate the first level signal; outputting the first level signal to the first control terminal through the output terminal of the first comparator; The NOT gate is configured to receive the first level signal and output the second level signal to the second control end through the output end of the NOT gate.

4. The image sensor according to claim 2 or 3, characterized in that: The light intensity contrast circuit further comprises: a regulating circuit; an output end of the regulating circuit is connected to an input end of the contrast circuit and serves as the second output end of the light intensity contrast circuit; The regulation circuit is connected to the first sub-pixel and is used to: receive the first output voltage; regulate the first output voltage to the target voltage according to the proportional relationship between the exposure time corresponding to the first sub-pixel and the exposure time corresponding to the second sub-pixel; and output the target voltage to the first input end of the comparison circuit.

5. The image sensor according to claim 3 or 4, characterized in that: The threshold voltage includes a first threshold voltage and a second threshold voltage; The threshold circuit includes a first threshold subcircuit and a second threshold subcircuit, and the first threshold subcircuit and the second threshold subcircuit both include the first control terminal and the second control terminal; a first threshold subcircuit connected to the second subpixel, configured to: receive the second output voltage, and upon receiving the first level signal through the first control terminal and the second level signal through the second control terminal, adjust the second output voltage upward to a first threshold voltage; a second threshold subcircuit connected to the second subpixel, configured to: receive the second output voltage, and adjust the second output voltage downward to a second threshold voltage after receiving the first level signal through the first control terminal and the second level signal through the second control terminal; The first threshold voltage is greater than the second threshold voltage.

6. The image sensor according to claim 5, wherein: The first threshold subcircuit includes a first capacitor, an op amp, a first switch tube, a second switch tube, a second capacitor, a third switch tube, and a third capacitor; the ratio of the first capacitor to the second capacitor is different from the ratio of the first capacitor to the third capacitor; One end of the first capacitor is connected to the second sub-pixel as the input end of the first threshold sub-circuit, and the other end of the first capacitor is connected to the input end of the operational amplifier; The first switch tube is connected between the input terminal and the output terminal of the operational amplifier; The second switch tube and the second capacitor are connected in series between the input terminal and the output terminal of the operational amplifier; The third switch tube and the third capacitor are connected in series between the input terminal and the output terminal of the operational amplifier; The output end of the operational amplifier is the output end of the first threshold sub-circuit connected to the second input end of the comparison circuit.

7. The image sensor according to claim 6, wherein: The control end of the first switch tube is used to receive a control signal, and the control signal is used to control the first switch tube to be turned on after the second sub-pixel starts to be exposed, and to be turned off before the second sub-pixel completes the exposure; The control end of the second switch tube is the first control end for receiving the first level signal, and the control end of the third switch tube is the second control end for receiving the second level signal.

8. The image sensor according to any one of claims 5 to 7, wherein: The second target level signal includes a third level signal and a fourth level signal; The comparison circuit is specifically configured to: compare the target voltage with the first threshold voltage and output a third level signal; and compare the target voltage with the second threshold voltage and output a fourth level signal.

9. The image sensor according to claim 8, wherein: The comparison circuit includes a second comparator and a third comparator; The first input terminal of the comparison circuit includes an input terminal of the second comparator and an input terminal of the third comparator; The second input terminal of the comparison circuit includes the other input terminal of the second comparator and the other input terminal of the third comparator; One input terminal of the second comparator is connected to the second output terminal to receive the target voltage, the other input terminal of the second comparator is connected to the output terminal of the first threshold sub-circuit to receive the first threshold voltage, and the second comparator is used to output the third level signal; One input terminal of the third comparator is connected to the second output terminal to receive the target voltage; the other input terminal of the third comparator is connected to the output terminal of the second threshold subcircuit to receive the second threshold voltage, and the third comparator is used to output the fourth level signal.

10. The image sensor according to claim 8 or 9, characterized in that: When the third level signal indicates that the target voltage is greater than the first threshold voltage, the brightness of the incident light intensity of the corresponding pixel changes from dark to bright; When the fourth level signal indicates that the target voltage is less than the second threshold voltage, the brightness of the incident light intensity of the corresponding pixel changes from bright to dark; When the third level signal and the fourth level signal indicate that the target voltage is greater than the second threshold voltage and less than the first threshold voltage, the brightness of the incident light intensity of the corresponding pixel remains unchanged.

11. An electronic device, characterized in that: The electronic device includes a circuit board and the image sensor according to any one of claims 1 to 10, wherein the circuit board is electrically connected to the image sensor.

12. A dynamic recognition system, characterized in that: The dynamic recognition system includes the image sensor according to any one of claims 1 to 10, and the image sensor is used for dynamic recognition.

Images