Exposure time adjustment method, device, adjustment equipment and storage medium

Abstract

The present application provides an exposure time adjustment method, device, adjustment equipment and storage medium, which relate to the field of ambient light detection technology. The method includes: determining the ambient light illumination through event-driven sensor EVS pixels; and determining the exposure time of active pixel sensor APS pixels according to the ambient light illumination. The exposure time adjustment method provided by the present application can prevent the problem that the ambient light in the high illumination range cannot be detected in the current ambient light detection technology. The exposure time of APS pixels is controlled by the ambient light illumination determined by EVS pixels, which can avoid overexposure or underexposure, thereby improving the image output quality.

Description

Technical Field

[0001] The present application relates to the field of ambient light detection technology, and in particular to an exposure time adjustment method, device, adjustment equipment and storage medium. Background Art

[0002] Nowadays, various consumer electronic products, whether computer monitors, LCD TVs, plasma TVs, or mobile phones, personal digital assistants (PDAs), digital cameras, handheld game consoles, or touch screens of automated teller machines (ATMs), all widely use flat panel display technology.

[0003] Based on the above needs, most of today's displays are equipped with light detection systems that can sense external light, so that when the flat-panel display senses changes in the external ambient light, it can appropriately change the brightness and color of the picture, allowing consumers to obtain better visual effects regardless of the external lighting conditions. Summary of the invention

[0004] The purpose of the embodiments of the present application is to provide an exposure time adjustment method, device, adjustment equipment and storage medium, so as to improve the recognition range of ambient light illumination and improve the output imaging quality of the displayed image.

[0005] In a first aspect, an embodiment of the present application provides an exposure time adjustment method, which may include:

[0006] Determine the ambient light level through event-driven sensor EVS pixels;

[0007] The exposure time of the active pixel sensor APS pixel is determined according to the ambient light illumination.

[0008] In the above implementation process, high ambient light illumination can be detected through EVS pixels, thereby preventing the problem that ambient light in a high illumination range cannot be detected in current ambient light detection technology. The exposure time of APS pixels is controlled by the ambient light illumination determined by EVS pixels, which can avoid overexposure or underexposure, thereby improving the image output quality.

[0009] Optionally, determining the ambient light illumination by using EVS pixels may include:

[0010] generating a first photocurrent based on incident light by the EVS pixel;

[0011] converting the first photocurrent into a first voltage through the EVS pixel;

[0012] The ambient light illumination is determined according to the first voltage.

[0013] Optionally, the relationship between the first photocurrent and the first voltage may include:

[0014]

[0015] Among them, V be is the first voltage, n is the process coefficient, V T is the thermal voltage, I s is the transmission saturation current, I ph is the first photocurrent, I rr is the unit plane illumination of ambient light, QE is the quantum efficiency, q is the electron charge, and A is the pixel area of ​​the EVS pixel.

[0016] In the above implementation process, the first photocurrent and the first voltage obtained by the EVS pixel detecting the ambient light illumination satisfy a logarithmic relationship, so even in the ambient light with a high illumination range, the first voltage is only close to the saturation voltage V max Therefore, it can still distinguish the corresponding ambient light illumination and control the appropriate exposure time to activate APS pixels to improve the quality of the output APS image.

[0017] Optionally, determining the exposure time of the APS pixel according to the ambient light illumination may include:

[0018] determining a second voltage of the APS pixel;

[0019] The exposure time of the APS pixel is determined according to the ambient light illumination.

[0020] Optionally, determining the second voltage of the APS pixel may include:

[0021] generating a second photocurrent based on incident light by the APS pixel;

[0022] The second photocurrent is converted into the second voltage by the APS pixel.

[0023] Optionally, determining the exposure time of the APS pixel according to the ambient light illumination may include:

[0024] The exposure time of the APS pixel is determined according to a correlation relationship among the ambient light illumination, the second voltage, and the exposure time.

[0025] Optionally, before determining the exposure time of the APS pixel according to the correlation relationship between the ambient light illumination, the second voltage and the exposure time, determining the exposure time of the APS pixel, the method may further include:

[0026] The correlation between the second voltage and the exposure time under different ambient light illuminations is calibrated.

[0027] Optionally, the calibrating the correlation between the second voltage and the exposure time under different ambient light illuminations may include:

[0028] Determining the ambient light illumination according to the first voltage;

[0029] determining the second voltage of the APS pixel;

[0030] The exposure time of the APS pixel is determined according to the ambient light illumination and the second voltage, and a correlation relationship among the ambient light illumination, the second voltage and the exposure time is obtained.

[0031] In the above implementation process, the EVS pixel can detect the ambient light illumination, and calibrate the correlation between the ambient light illumination, the second voltage obtained by the APS pixel detection and the corresponding APS pixel exposure time. The exposure time of the APS pixel can be controlled through the correlation. In the specific implementation process, it is only necessary to obtain the correspondence table between the ambient light illumination and the second voltage according to the preliminary test results, and the exposure time of the APS pixel can be determined based on the table lookup, thereby improving the control efficiency and saving computing resources.

[0032] Optionally, the correlation relationship between the ambient light illumination, the second voltage and the exposure time may include:

[0033]

[0034] Wherein, V is the second voltage, I rr is the unit plane illumination of the ambient light, QE is the quantum efficiency, q is the electron charge, h is the Planck constant, v is the frequency of the first photocurrent, A is the pixel area of ​​the EVS pixel, t is the exposure time, C SN is the capacitance of the floating diffusion node.

[0035] In the above implementation process, the embodiment of the present application can obtain the correspondence table between the ambient light illumination and the second voltage based on the preliminary test results to perform calibration table lookup control, or directly control the exposure time through the correlation between the ambient light illumination, the second voltage and the exposure time. In this way, the exposure time of the APS pixel can be accurately controlled to avoid overexposure or underexposure, thereby achieving the effect of outputting higher quality images while improving control flexibility, thereby improving user experience.

[0036] In a second aspect, an embodiment of the present application provides an exposure time adjustment device, which may include:

[0037] Illuminance determination means, for determining ambient light illuminance through event-driven sensor EVS pixels;

[0038] The exposure time determining device is used to determine the exposure time of an active pixel sensor APS pixel according to the ambient light illumination.

[0039] In the above implementation process, high ambient light illumination can be detected through EVS pixels, thereby preventing the problem that ambient light in a high illumination range cannot be detected in current ambient light detection technology. The exposure time of APS pixels is controlled by the ambient light illumination determined by EVS pixels, which can avoid overexposure or underexposure, thereby improving the image output quality.

[0040] Optionally, the illumination determination device may be specifically used for:

[0041] generating a first photocurrent based on incident light by the EVS pixel;

[0042] converting the first photocurrent into a first voltage through the EVS pixel;

[0043] The ambient light illumination is determined according to the first voltage.

[0044] Optionally, the exposure time determining device may be specifically used for:

[0045] determining a second voltage of the APS pixel;

[0046] The exposure time of the APS pixel is determined according to the ambient light illumination.

[0047] Optionally, the exposure time determining device may be specifically used for:

[0048] generating a second photocurrent based on incident light by the APS pixel;

[0049] The second photocurrent is converted into the second voltage by the APS pixel.

[0050] Optionally, the exposure time determining device may also be used to:

[0051] The exposure time of the APS pixel is determined according to a correlation relationship among the ambient light illumination, the second voltage, and the exposure time.

[0052] Optionally, the exposure time adjustment device may further include a calibration module for calibrating the correlation between the second voltage and the exposure time under different ambient light illuminations.

[0053] Optionally, the calibration module may be specifically used for:

[0054] Determining the ambient light illumination according to the first voltage;

[0055] determining the second voltage of the APS pixel;

[0056] The exposure time of the APS pixel is determined according to the ambient light illumination and the second voltage, and a correlation relationship among the ambient light illumination, the second voltage and the exposure time is obtained.

[0057] In a third aspect, an embodiment of the present application provides an exposure time adjustment device, which includes a memory and a processor, wherein program instructions are stored in the memory, and when the processor reads and runs the program instructions, the steps in any of the above-mentioned implementation methods are executed.

[0058] Optionally, the exposure time adjustment device may further include EVS pixels and APS pixels, wherein the EVS pixels are used to detect the ambient light illumination, and when the processor receives the ambient light illumination, it executes the steps in any of the above implementations.

[0059] Optionally, EVS pixels and APS pixels can be located in the same pixel array, and their number and distribution can be set according to requirements, such as each occupying half of the pixel array or setting a single or multiple EVS pixels only for detecting ambient light illumination. The arrangement of EVS pixels and APS pixels is not limited to regular arrangement, cross arrangement, etc., and it can be used to simultaneously output EVS images and high-quality APS images.

[0060] Optionally, the exposure time adjustment device provided in the embodiment of the present application can be applied to static scenes with high resolution requirements, such as face recognition. When the exposure time adjustment device is applied to face recognition, the EVS pixel is set outside the pixel array and is only used to detect ambient light illumination, thereby controlling the exposure time of the APS pixel and improving the quality of the output APS image.

[0061] Optionally, the exposure time adjustment device provided in the embodiment of the present application can also be applied to some scenarios with a large dynamic range and high resolution, such as autonomous driving. When the exposure time adjustment device is applied to autonomous driving, the EVS pixels and APS pixels can be set to be located in different pixel arrays, thereby being able to simultaneously output high-resolution EVS images and high-resolution APS images.

[0062] In a fourth aspect, an embodiment of the present application further provides a computer-readable storage medium, wherein the computer-readable storage medium stores computer program instructions, and when the computer program instructions are read and executed by a processor, the steps in any of the above-mentioned implementation methods are executed. BRIEF DESCRIPTION OF THE DRAWINGS

[0063] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments of the present application will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0064] Figure 1 Schematic diagram of an ambient light detection system based on a traditional APS pixel;

[0065] Figure 2 A schematic diagram of the relationship between the sensing current and the readout voltage corresponding to different light in the ambient light detection system;

[0066] Figure 3 A schematic diagram of the steps of the exposure time adjustment method provided in an embodiment of the present application;

[0067] Figure 4 A schematic diagram of the steps for determining the ambient light illumination provided in an embodiment of the present application;

[0068] Figure 5 A schematic diagram of the relationship between the first photocurrent and the first voltage corresponding to the EVS pixel provided in an embodiment of the present application;

[0069] Figure 6 A schematic diagram of the steps of determining the exposure time of an APS pixel according to the ambient light illumination provided in an embodiment of the present application;

[0070] Figure 7 A schematic diagram of the steps of determining the second voltage of an APS pixel provided in an embodiment of the present application;

[0071] Figure 8 A schematic diagram of the steps for calibrating the correlation between the second voltage and the exposure time under different ambient light illuminations provided in an embodiment of the present application;

[0072] Fig. 9 A schematic diagram of an exposure time adjustment device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0073] The technical solutions in the embodiments of the present application will be described below in conjunction with the accompanying drawings in the embodiments of the present application. For example, the flowcharts and block diagrams in the accompanying drawings show the possible architectures, functions and operations of the systems, methods and computer program products according to multiple embodiments of the present invention. In this regard, each box in the flowchart or block diagram may represent a module, a program segment or a part of a code, and the module, a program segment or a part of a code contains one or more executable instructions for implementing the specified logical functions. It should also be noted that in some alternative implementations, the functions marked in the box may also occur in an order different from that marked in the accompanying drawings. For example, two consecutive boxes can actually be executed substantially in parallel, and they may sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each box in the block diagram and / or the flowchart, and the combination of boxes in the block diagram and / or the flowchart, can be implemented by a dedicated hardware-based system that performs a specified function or action, or can be implemented by a combination of dedicated hardware and computer instructions. In addition, the functional modules in the various embodiments of the present invention can be integrated together to form an independent part, or each module can exist separately, or two or more modules can be integrated to form an independent part.

[0074] The applicant discovered during the research that the currently commonly used method for adjusting the color and brightness of the display according to the ambient light is based on the ambient light detection method of the active pixel sensor (APS) pixel. Figure 1 , Figure 1 Schematic diagram of an ambient light detection system based on a traditional APS pixel, the ambient light detection system 10 includes an input unit 11, a transmission unit 12, a storage unit 13 and a readout unit 14, wherein the input unit 11 is configured to perform photoelectric conversion of incident light and accumulate photocharges corresponding to the incident light during the exposure time; the transmission unit 12 is configured to transfer the photocharges accumulated by the input unit 11 to the storage unit 13; the readout unit 14 is configured to read out the voltage V of the storage unit 13. The input unit 11 may include a photodiode, a phototransistor, a clamped photodiode or any other similar device. In the ambient light detection method based on APS pixels, the integral relationship between the readout voltage V and the light-induced current I can be expressed as:

[0075]

[0076] Among them, T 0is the integration start time, T is the integration time period, and at the end of the integration time period T, the controller and the processor perform a discharge operation on the feedback capacitor C, thereby resetting the read voltage V. In the operation of the conventional APS camera ambient light detection system 10, the integration time period T is a fixed integration time period. During the integration time period T, the feedback capacitor C continuously accumulates charge due to the light-induced current I, thereby causing the read voltage V to continuously increase.

[0077] Please continue to see Figure 2 , Figure 2 The relationship between the light sensing current and the readout voltage in the ambient light detection system is shown in FIG. Figure 2 It is easy to know that the readout voltage V and the light sensing current I of the ambient light detection system 10 satisfy a linear relationship. Within the integration time T, corresponding to the light sensing current I 1 ,I 2 and I 3 The output voltages are V 1 、V 2 and V 3 , since none of the three light-induced currents reaches the saturation voltage V max , so the ambient light detection system 10 can distinguish the corresponding ambient light illumination. 4 , since the output voltage has reached the saturation voltage V max Therefore, the ambient light detection system 10 cannot distinguish the light-induced current I 4 The corresponding ambient light intensity.

[0078] It is easy to know from the above that if the ambient light detection system 10 is used to detect ambient light in a high illumination range, unless a sufficiently small integration period is set, the readout voltage V will reach the saturation voltage V max However, when a sufficiently small integration period is set to distinguish the ambient light in the high illumination range, the generated readout voltage V will be too small for the ambient light in the low illumination range, thereby reducing the signal-to-noise ratio and resulting in a reduced noise tolerance of the ambient light detection system 10.

[0079] In addition, there is a light detection system for detecting a wide range of ambient light illumination, which usually uses several light detection elements with different photosensitivity to detect ambient light with different illumination ranges, such as using a light detection element with high photosensitivity to detect ambient light with low illumination, and using a light detection element with low photosensitivity to detect ambient light with high illumination. Alternatively, several feedback capacitors with different capacitance values ​​can be used to match the readout voltage, such as using a feedback capacitor with a high capacitance value to generate a readout voltage corresponding to ambient light with high illumination, and using a feedback capacitor with a low capacitance value to generate a readout voltage corresponding to ambient light with low illumination. However, this light detection system composed of multiple optional light detection elements to generate readout voltages corresponding to different ambient light illuminations will significantly increase the complexity of the system and increase production costs.

[0080] Therefore, the embodiment of the present application provides an exposure time adjustment method, which can realize the detection characteristics of high ambient light intensity by utilizing the large dynamic range of EVS pixels and the logarithmic relationship between the light-sensing current and voltage, thereby controlling the appropriate exposure time to activate APS pixels and improve the quality of the output APS image. Figure 3 , Figure 3 The following is a schematic diagram of the steps of the exposure time adjustment method provided in an embodiment of the present application. The steps of the exposure time adjustment method may include:

[0081] In step S31, the ambient light illumination is determined by an event-based vision sensor (EVS) pixel.

[0082] Among them, EVS imitates the retinal nerve of the human eye, allowing each pixel to work independently, and output changing pulse signals or event stream signals by sensing changes in external light intensity. That is, it uses the event-driven principle to capture key information in a scene, thereby reducing data redundancy and delay.

[0083] Specifically, EVS is based on the photodiode (PD) current and monitors whether the current signal of the PD has changed. Exemplarily, when the change exceeds a given threshold, it can be output as a 2-bit signal; that is, it becomes stronger by 01 or weaker by 10. If the change does not exceed the threshold, it is 00; thus, it can respond to high-frequency signals, that is, rapidly changing objects. At the same time, its calculation process is the digital-to-analog conversion of all pixels in parallel at the same time. And because the conversion is simple, this 2-bit digital-to-analog conversion is very fast, thereby realizing very high-speed conversion and output of the entire pixel array, achieving a high frame rate.

[0084] In step S32, the exposure time of an active pixel sensor (APS) pixel is determined according to the ambient light illumination.

[0085] Among them, APS is composed of active pixels, each of which contains one or more MOSFET amplifiers that can convert photogenerated charges into voltage, amplify signal voltage and reduce noise. APS pixels are integrated with photodiodes (PDs), active transistor switches and amplifier circuits. These active circuits complete the charge-voltage conversion on each pixel and amplify it into a signal voltage with driving capability. Then, the pixel signal can be switched to an external device using conventional electronic circuit methods to achieve the output of the image signal.

[0086] Specifically, after the EVS pixel detects the ambient light illumination, the exposure time of the APS pixel can be controlled based on a preset relationship between the exposure times of the EVS pixel and the APS pixel.

[0087] It can be seen that the embodiments of the present application can realize the detection of high ambient light illumination through EVS pixels, thereby preventing the problem that the ambient light in the high illumination range cannot be detected in the current ambient light detection technology. By controlling the exposure time of the APS pixel according to the ambient light illumination determined by the EVS pixel, overexposure or underexposure can be avoided, thereby improving the image output quality.

[0088] In an optional embodiment, for step S31, the present application embodiment provides a method for determining the ambient light illumination, see Figure 4 , Figure 4 A schematic diagram of the steps for determining the ambient light illumination provided in an embodiment of the present application, wherein the ambient light illumination may include:

[0089] In step S41 , a first photocurrent is generated by the EVS pixel based on incident light.

[0090] In step S42, the first photocurrent is converted into a first voltage by the EVS pixel.

[0091] In step S43, the ambient light illumination is determined according to the first voltage.

[0092] Exemplarily, the EVS may include an input unit, a current-voltage conversion unit, and a readout unit, wherein the input unit may be configured to perform photoelectric conversion of incident light and generate a first photocurrent corresponding to the incident light; the current-voltage conversion unit may be configured to convert the first photocurrent corresponding to the incident light into a first voltage; and the readout unit may be configured to read out the first voltage. The input unit may include a photodiode, a phototransistor, a clamped photodiode, or any other similar device.

[0093] Specifically, the EVS may convert the first photocurrent into the first voltage based on the relationship between the first photocurrent and the first voltage, and the relationship between the first photocurrent and the first voltage may be:

[0094]

[0095] The above relationship can be expressed by Get, and among them Thus, the relationship between the first photocurrent and the first voltage can be obtained.

[0096] Among them, V be is the first voltage, n is the process coefficient, V T is the thermal voltage, I s is the transmission saturation current, I ph is the first photocurrent, I rr is the unit plane illumination of ambient light, QE is the quantum efficiency, q is the electron charge, and A is the pixel area of ​​the EVS pixel.

[0097] For example, please Figure 4 Continue to refer to Figure 5 , Figure 5 A schematic diagram of the relationship between the first photocurrent and the first voltage corresponding to the EVS pixel provided in the embodiment of the present application is shown as follows: Figure 5 It is easy to know that the first photocurrent and the first voltage satisfy a logarithmic relationship. The first photocurrent I ph1 ,I ph2 and I ph3 The corresponding first voltages are V be1 、V be2 and V be3 , since none of the three first voltages reaches the saturation voltage V max , so the EVS pixel can distinguish the corresponding ambient light illumination.

[0098] It can be seen that in the embodiment provided in the present application, the first photocurrent and the first voltage obtained by the EVS pixel detecting the ambient light illumination satisfy a logarithmic relationship, so even under the ambient light in the high illumination range, the first voltage is only close to the saturation voltage V max Therefore, it can still distinguish the corresponding ambient light illumination and control the appropriate exposure time to activate APS pixels to improve the quality of the output APS image.

[0099] Optionally, for step S32, the present application embodiment provides an implementation method for determining the exposure time of the APS pixel according to the ambient light illumination, see Figure 6 , Figure 6 A schematic diagram of the steps of determining the exposure time of an APS pixel according to the ambient light illumination provided in an embodiment of the present application, wherein the step of determining the exposure time of an APS pixel according to the ambient light illumination may include:

[0100] In step S61, a second voltage of the APS pixel is determined.

[0101] In step S62, the exposure time of the APS pixel is determined according to the ambient light illumination.

[0102] Specifically, with respect to step S61, the present application embodiment provides an implementation method for determining the second voltage of the APS pixel, see Figure 7 , Figure 7 A schematic diagram of the steps of determining the second voltage of an APS pixel provided in an embodiment of the present application, wherein the steps of determining the second voltage of an APS pixel may include:

[0103] In step S71 , a second photocurrent is generated by the APS pixel based on incident light.

[0104] In step S72 , the second photocurrent is converted into the second voltage by the APS pixel.

[0105] The APS may include an input unit, a transmission unit, a storage unit, and a readout unit. The input unit may be configured to perform photoelectric conversion of incident light and accumulate photocharges corresponding to the incident light during an exposure time to obtain a second photocurrent corresponding to the incident light; the transmission unit may be configured to transfer the photocharges accumulated by the input unit to the storage unit; and the readout unit may be configured to read out the second voltage of the storage unit. The input unit may include a photodiode, a phototransistor, a clamped photodiode, or any other similar device.

[0106] Specifically, the APS may convert the second photocurrent into the second voltage based on the relationship between the second photocurrent and the second voltage, wherein the relationship between the second photocurrent and the second voltage is:

[0107]

[0108] Among them, T 0 is the integration start time, T is the integration time period, and at the end of the integration time period T, the controller and the processor execute the discharge operation of the feedback capacitor C, thereby resetting the read-out second voltage V. In the operation of the APS, the integration time period T is a fixed integration time period. During the integration time period T, the feedback capacitor C continuously accumulates charge due to the second photocurrent I to obtain the corresponding second voltage.

[0109] Optionally, after executing step S61 to determine the second voltage of the APS pixel, for step S62, the exposure time of the APS pixel may be determined according to a correlation relationship among the ambient light illumination, the second voltage and the exposure time.

[0110] In an embodiment of the present application, the step of obtaining the correlation between the ambient light illumination, the second voltage and the exposure time may be performed before determining the exposure time of the APS pixel. Optionally, the correlation between the second voltage and the exposure time under different ambient light illuminations may be determined by calibration, thereby determining the exposure time corresponding to the APS pixel under each ambient light illumination based on the calibrated relationship.

[0111] Specifically, the ambient light illumination is detected by the EVS pixel, and the relationship between the unit plane illumination of the ambient light and the second voltage of the APS pixel can be obtained in advance through calibration or other methods, that is, each unit plane illumination of the ambient light corresponds to a second voltage, thereby obtaining the exposure time corresponding to the APS pixel under different ambient light illuminations. Figure 8 , Figure 8 A schematic diagram of the steps for calibrating the correlation between the second voltage and the exposure time under different ambient light illuminations provided in an embodiment of the present application, wherein the step of calibrating the correlation between the second voltage and the exposure time may include:

[0112] In step S81, the ambient light illumination is determined according to the first voltage.

[0113] In step S82, the second voltage of the APS pixel is determined.

[0114] Among them, the implementation method of determining the ambient light illumination according to the first voltage can be specifically referred to the description of the above steps S41 to S43, and the implementation method of determining the second voltage of the APS pixel can be specifically referred to the description of the above steps S61 to S62 and steps S71 to S72, which will not be repeated here.

[0115] In step S83, the exposure time of the APS pixel is determined according to the ambient light illumination and the second voltage, and a correlation relationship among the ambient light illumination, the second voltage and the exposure time is obtained.

[0116] For example, when the ambient light illuminance is actually tested, each ambient light illuminance can be tested first based on the above implementation steps to obtain a correspondence table between the ambient light illuminance and the second voltage. For example, when the ambient light illuminance is 3lx, the corresponding second voltage is 1V, and when the ambient light illuminance is 5lx, the corresponding second voltage is 2V. By inputting the correspondence table between the ambient light illuminance and the second voltage into the control device, an ambient light illuminance or a range of ambient light illuminances is controlled to correspond to a voltage value, thereby controlling the exposure time of the APS pixel.

[0117] It can be seen that the embodiment of the present application can detect the ambient light illumination by the EVS pixel, and calibrate the correlation between the ambient light illumination, the second voltage obtained by the APS pixel detection, and the corresponding APS pixel exposure time, and realize the control of the exposure time of the APS pixel through the correlation relationship. In the specific implementation process, it is only necessary to obtain the correspondence table between the ambient light illumination and the second voltage according to the preliminary test results, and then the exposure time of the APS pixel can be determined based on the table lookup, thereby improving the control efficiency and saving computing resources.

[0118] In addition, in addition to controlling the exposure time of the APS pixel based on the calibration lookup table in the above embodiment, the embodiment of the present application can also control the exposure time of the APS pixel based on the correlation between the ambient light illumination, the second voltage and the exposure time, wherein the correlation between the ambient light illumination, the second voltage and the exposure time may include:

[0119]

[0120] Specifically, the correlation between the ambient light illumination, the second voltage and the exposure time can be based on the formula as well as Conclude.

[0121] Wherein, V is the second voltage, I rr is the unit plane illumination of the ambient light, QE is the quantum efficiency, q is the electron charge, h is the Planck constant, v is the frequency of the first photocurrent, A is the pixel area of ​​the EVS pixel, t is the exposure time, C SN is the capacitance of the floating diffusion node.

[0122] It can be seen that the embodiments of the present application can obtain the correspondence table between the ambient light illumination and the second voltage based on the preliminary test results to perform calibration table lookup control, or directly control the exposure time through the correlation between the ambient light illumination, the second voltage and the exposure time. In this way, the exposure time of the APS pixel can be accurately controlled to avoid overexposure or underexposure, thereby achieving the effect of outputting higher quality images while improving control flexibility, thereby improving user experience.

[0123] Based on the same inventive concept, the present application embodiment also provides an exposure time adjustment device 90, please refer to Fig. 9 , Fig. 9 This is a schematic diagram of an exposure time adjustment device provided in an embodiment of the present application. The exposure time adjustment device 90 may include:

[0124] The illumination determination device 91 is used to determine the ambient light illumination by using pixels of the event-driven sensor EVS.

[0125] The exposure time determining device 92 is used to determine the exposure time of the active pixel sensor APS pixel according to the ambient light illumination.

[0126] It can be seen that the embodiments of the present application can realize the detection of high ambient light illumination through EVS pixels, thereby preventing the problem that the ambient light in the high illumination range cannot be detected in the current ambient light detection technology. By controlling the exposure time of the APS pixel according to the ambient light illumination determined by the EVS pixel, overexposure or underexposure can be avoided, thereby improving the image output quality.

[0127] Optionally, the illumination determination device 91 may be specifically used for:

[0128] generating a first photocurrent based on incident light by the EVS pixel;

[0129] converting the first photocurrent into a first voltage through the EVS pixel;

[0130] The ambient light illumination is determined according to the first voltage.

[0131] Optionally, the exposure time determining device 92 may be specifically configured to:

[0132] determining a second voltage of the APS pixel;

[0133] The exposure time of the APS pixel is determined according to the ambient light illumination.

[0134] Optionally, the exposure time determining device 92 may be specifically configured to:

[0135] generating a second photocurrent based on incident light by the APS pixel;

[0136] The second photocurrent is converted into the second voltage by the APS pixel.

[0137] Optionally, the exposure time determining device 92 may also be used for:

[0138] The exposure time of the APS pixel is determined according to a correlation relationship among the ambient light illumination, the second voltage, and the exposure time.

[0139] Optionally, the exposure time adjustment device 90 may further include a calibration module for calibrating the correlation between the second voltage and the exposure time under different ambient light illuminations.

[0140] Optionally, the calibration module may be specifically used for:

[0141] Determining the ambient light illumination according to the first voltage;

[0142] determining the second voltage of the APS pixel;

[0143] The exposure time of the APS pixel is determined according to the ambient light illumination and the second voltage, and a correlation relationship among the ambient light illumination, the second voltage and the exposure time is obtained.

[0144] Based on the same inventive concept, an embodiment of the present application also provides an exposure time adjustment device, which includes a memory and a processor, wherein program instructions are stored in the memory, and when the processor reads and runs the program instructions, the steps in any of the above implementation methods are executed.

[0145] Optionally, the exposure time adjustment device may further include EVS pixels and APS pixels, wherein the EVS pixels are used to detect the ambient light illumination, and when the processor receives the ambient light illumination, it executes the steps in any of the above implementations.

[0146] Optionally, EVS pixels and APS pixels can be located in the same pixel array, and their number and distribution can be set according to requirements, such as each occupying half of the pixel array or setting a single or multiple EVS pixels only for detecting ambient light illumination. The arrangement of EVS pixels and APS pixels is not limited to regular arrangement, cross arrangement, etc., and it can be used to simultaneously output EVS images and high-quality APS images.

[0147] Optionally, the exposure time adjustment device provided in the embodiment of the present application can be applied to static scenes with high resolution requirements, such as face recognition. When the exposure time adjustment device is applied to face recognition, the EVS pixel is set outside the pixel array and is only used to detect ambient light illumination, thereby controlling the exposure time of the APS pixel and improving the quality of the output APS image.

[0148] Optionally, the exposure time adjustment device provided in the embodiment of the present application can also be applied to some scenarios with a large dynamic range and high resolution, such as autonomous driving. When the exposure time adjustment device is applied to autonomous driving, the EVS pixels and APS pixels can be set to be located in different pixel arrays, thereby being able to simultaneously output high-resolution EVS images and high-resolution APS images.

[0149] Based on the same inventive concept, an embodiment of the present application further provides a computer-readable storage medium, in which computer program instructions are stored. When the computer program instructions are read and executed by a processor, the steps in any of the above implementation methods are executed.

[0150] The computer-readable storage medium may be a random access memory (RAM), a read-only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), or any other medium that can store program codes. The storage medium is used to store the program, and the processor executes the program after receiving the execution instruction. The method executed by the electronic terminal of the process definition disclosed in any embodiment of the present invention can be applied to the processor or implemented by the processor.

[0151] In the embodiments provided in the present application, it should be understood that the disclosed devices and methods can be implemented in other ways. The device embodiments described above are merely schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation. For example, 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 communication interfaces, and the indirect coupling or communication connection of the devices or units can be electrical, mechanical or other forms.

[0152] In addition, the units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0153] Furthermore, the functional modules in the various embodiments of the present application may be integrated together to form an independent part, or each module may exist independently, or two or more modules may be integrated to form an independent part.

[0154] Alternatively, the present invention may be implemented in whole or in part by software, hardware, firmware, or any combination thereof. When implemented by software, the present invention may be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, the process or function described in the embodiment of the present invention is generated in whole or in part.

[0155] The computer may be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions may be stored in a computer-readable storage medium, or transmitted from one computer-readable storage medium to another computer-readable storage medium. For example, the computer instructions may be transmitted from one website, computer, server, or data center to another website, computer, server, or data center via wired (e.g., coaxial cable, optical fiber, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) means.

[0156] In this article, relational terms such as first and second, etc. are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the statement "include..." do not exclude the presence of other identical elements in the process, method, article or device including the elements.

[0157] The above description is only an embodiment of the present application and is not intended to limit the protection scope of the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A method for adjusting exposure time, characterized in that: The method comprises: The ambient light illumination is determined by an event-driven sensor EVS pixel; the EVS includes an input unit, a current-voltage conversion unit and a readout unit, the input unit is configured to perform photoelectric conversion of incident light and generate a first photocurrent corresponding to the incident light, the current-voltage conversion unit is configured to convert the first photocurrent corresponding to the incident light into a first voltage, the readout unit is configured to read out the first voltage, the input unit includes a photodiode, a phototransistor or a clamped photodiode, and the first voltage is used to indicate the ambient light illumination; The exposure time of the active pixel sensor APS pixel is determined according to the ambient light illumination.

2. The method according to claim 1, characterized in that Determining the ambient light illumination by using EVS pixels includes: generating a first photocurrent based on incident light by the EVS pixel; converting the first photocurrent into a first voltage through the EVS pixel; The ambient light illumination is determined according to the first voltage.

3. The method according to claim 1 or 2, characterized in that: The step of determining the exposure time of the APS pixel according to the ambient light illumination comprises: determining a second voltage of the APS pixel; The exposure time of the APS pixel is determined according to the ambient light illumination.

4. The method according to claim 3, characterized in that The determining the second voltage of the APS pixel comprises: generating a second photocurrent based on incident light by the APS pixel; The second photocurrent is converted into the second voltage by the APS pixel.

5. The method according to claim 4, characterized in that The step of determining the exposure time of the APS pixel according to the ambient light illumination includes: The exposure time of the APS pixel is determined according to a correlation relationship among the ambient light illumination, the second voltage, and the exposure time.

6. The method according to claim 5, characterized in that Before determining the exposure time of the APS pixel according to the correlation between the ambient light illumination, the second voltage, and the exposure time, the method further includes: The correlation between the second voltage and the exposure time under different ambient light illuminations is calibrated.

7. The method according to claim 6, characterized in that The calibrating the correlation between the second voltage and the exposure time under different ambient light illuminations includes: Determining the ambient light illumination according to the first voltage; determining the second voltage of the APS pixel; The exposure time of the APS pixel is determined according to the ambient light illumination and the second voltage, and a correlation relationship among the ambient light illumination, the second voltage and the exposure time is obtained.

8. The method according to claim 2, characterized in that: The relationship between the first photocurrent and the first voltage includes: Among them, V be is the first voltage, n is the process coefficient, V T is the thermal voltage, I s is the transmission saturation current, I ph is the first photocurrent, I rr is the unit plane illumination of ambient light, QE is the quantum efficiency, q is the electron charge, and A is the pixel area of ​​the EVS pixel.

9. The method according to claim 5, characterized in that The correlation relationship between the ambient light illumination, the second voltage and the exposure time includes: Wherein, V is the second voltage, I rr is the unit plane illumination of the ambient light, QE is the quantum efficiency, q is the electron charge, h is the Planck constant, v is the frequency of the first photocurrent, A is the pixel area of ​​the EVS pixel, t is the exposure time, C SN is the capacitance of the floating diffusion node.

10. An exposure time adjustment device, characterized in that: The device comprises: An illuminance determination device, for determining the ambient light illuminance through an event-driven sensor EVS pixel; the EVS comprises an input unit, a current-voltage conversion unit and a readout unit, the input unit is configured to perform photoelectric conversion of incident light and generate a first photocurrent corresponding to the incident light, the current-voltage conversion unit is configured to convert the first photocurrent corresponding to the incident light into a first voltage, the readout unit is configured to read out the first voltage, the input unit comprises a photodiode, a phototransistor or a clamped photodiode, and the first voltage is used to indicate the ambient light illuminance; The exposure time determining device is used to determine the exposure time of an active pixel sensor APS pixel according to the ambient light illumination.

11. An exposure time adjustment device, characterized in that: The method comprises a memory and a processor, wherein the memory is used to store a set of computer instructions; when the processor executes the set of computer instructions, the operation steps of the method described in any one of claims 1 to 9 are performed.

12. The device according to claim 11, characterized in that The device further includes an EVS pixel and an APS pixel, wherein the EVS pixel is used to detect ambient light illumination, and when the processor receives the ambient light illumination, the processor executes the operation steps of any one of the methods of claims 1-9.

13. A readable storage medium, characterized in that: The readable storage medium stores computer program instructions, and when the computer program instructions are executed by a processor, the steps in the method according to any one of claims 1 to 9 are executed.

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