Image sensor, exposure control method, imaging module and electronic device

Abstract

This application discloses an image sensor, an exposure control method, a photographing module and an electronic device, which belong to the technical field of image processing. The image sensor includes a photosensitive element (1111), a reset switch (1116) and a signal control circuit, the signal control circuit includes a voltage logic judgment module (1115) and a logic control module (1118), the voltage logic judgment module (1115) has a first end connected to the first end of the photosensitive element (1111) and a second end connected to the second end of the photosensitive element (1111), the logic control module (1118) has a first input end connected to the first end of the voltage logic judgment module (1115) and an output end connected to the reset switch (1116), the first input end of the logic control module (1118) is used for receiving a count signal, and the second input end of the logic control module (1118) is used for receiving a control signal.

Description

[Technical field]

[0001] (CROSS REFERENCE TO RELATED APPLICATIONS) This application claims priority to a Chinese patent application filed on December 30, 2021, bearing application number 202111680855.X and titled "Image sensor, exposure control method, photographing module, and electronic device," the entire contents of which are incorporated herein by reference.

[0002] The present application relates to the technical field of image processing, and in particular to an image sensor, an exposure control method, a photographing module, and an electronic device. [Background technology]

[0003] The quality of the image captured by the camera of a smart device depends on the exposure accuracy of the image sensor. The currently mainstream exposure method is the global shutter, which sets the same exposure parameters for each pixel unit to complete the image capture.

[0004] In such exposure modes, there are many situations where the light-touched side is overexposed or the light-unlit side is underexposed, resulting in image distortion. Summary of the Invention

[0005] The present application aims to provide an image sensor, an exposure control method, an imaging module, and an electronic device to solve the problem of overexposure on the side illuminated by a light source or underexposure on the side not illuminated by a light source.

[0006] In order to solve the above technical problems, the present application is realized as follows.

[0007] In a first aspect, an embodiment of the present application is an image sensor including a photosensitive element, a reset switch, and a signal control circuit, the signal control circuit including a voltage logic judgment module and a logic control module; the voltage logic judgment module has a first end connected to a first end of the photosensitive element and a second end connected to a second end of the photosensitive element, and when the voltage logic judgment module detects that a voltage difference between both ends of the photosensitive element reaches a preset voltage threshold, the voltage logic judgment module is used to output an automatic control signal for controlling the reset switch to be on, so that the electrons in the photosensitive element are empty, and output a count signal to a first input end of the logic control module; The image sensor disclosed herein is one in which the logic control module has a first input terminal connected to a first terminal of the voltage logic judgment module and an output terminal connected to the reset switch, the first input terminal of the logic control module is used for receiving a count signal, and the second input terminal of the logic control module is used for receiving a control signal, and the logic control module is used for controlling the reset switch to be on, so that the electrons in the photosensitive element are emptied when the control signal meets a preset condition.

[0008] In a second aspect, an embodiment of the present application is an exposure control method applied to the image sensor according to the first aspect of the embodiment of the present application, comprising: obtaining a preset brightness of a first image, and a first partition brightness and a first exposure amount corresponding to each image region of the first image; obtaining a second exposure amount corresponding to each of the image regions according to the preset brightness, a first partition brightness corresponding to each of the image regions, and a first exposure amount; and exposing a second image captured by the image sensor according to a second exposure amount corresponding to each of the image areas.

[0009] In a third aspect, an embodiment of the present application discloses a photographing module including the image sensor according to the first aspect of the embodiment of the present application.

[0010] In a fourth aspect, an embodiment of the present application discloses an electronic device including the imaging module according to the third aspect of the embodiment of the present application.

[0011] In an embodiment of the present application, the image sensor includes a photosensitive element, a reset switch and a signal control circuit, the signal control circuit includes a voltage logic judgment module and a logic control module. The voltage logic judgment module has a first end connected to a first end of the photosensitive element and a second end connected to a second end of the photosensitive element, the voltage logic judgment module is used to output an automatic control signal for controlling the reset switch to be on so that the electrons in the photosensitive element are empty when it detects that the voltage difference between both ends of the photosensitive element reaches a preset voltage threshold, and is used to output a count signal to a first input end of the logic control module. The logic control module has a first input end connected to the first end of the voltage logic judgment module and an output end connected to the reset switch, the first input end of the logic control module is used to receive the count signal, and the second input end of the logic control module is used to receive the control signal, the logic control module is used to control the reset switch to be on so that the electrons in the photosensitive element are empty when the control signal meets a preset condition. In this way, the logic control module is provided to control the on / off of the reset switch, and the voltage logic judgment module can output a counting signal, so that the photosensitive signal of the photosensitive element can be accurately obtained after the exposure is completed, and the situation of overexposure occurring on the side exposed by the light source or underexposure occurring on the side not exposed by the light source can be avoided, thereby realizing the high dynamic photosensitive function of the pixel unit and improving the image quality level.

[0012] In addition, the embodiment of the present application can realize a differential exposure for each image area, thereby improving the exposure accuracy and further improving the image quality level.

[0013] The above and / or additional aspects and advantages of the present application will become more apparent and understandable from the following description of the embodiments with reference to the drawings, in which: [Brief description of the drawings]

[0014] [Figure 1] FIG. 2 is a structural schematic diagram of a pixel unit provided in an embodiment of the present application; [Diagram 2] FIG. 2 is a schematic diagram of the array structure of pixel units of an image sensor provided in an embodiment of the present application; [Diagram 3] FIG. 2 is a schematic diagram of a circuit structure of a pixel unit in FIG. [Figure 4] FIG. 2 is a schematic diagram of the array structure of the imaging module provided in the embodiment of the present application; [Diagram 5] 1 is a schematic flow chart of an exposure control method provided in an embodiment of the present application. [Figure 6] FIG. 2 is a structural schematic diagram of another imaging module provided in an embodiment of the present application. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] Hereinafter, the embodiments of the present application will be described in detail, and illustrative examples of the described embodiments are shown in the drawings, in which the same or similar reference numerals throughout the drawings represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the drawings are illustrative and are intended only to interpret the present application, and should not be understood as limiting the present application. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without requiring creative efforts all belong to the scope of protection of this application.

[0016] In the present specification and claims, the terms "first" and "second" feature may state or imply the inclusion of one or more of said features, and "and / or" in the specification and claims denotes at least one of the connected features.

[0017] In describing the present application, it should be understood that orientations or positional relationships indicated by terms such as "center," "row direction," "column direction," "top," "bottom," "periphery," etc. are based on the drawings and are intended merely to facilitate explanation and simplify the description of the present application, and should not be understood as limiting the present application, as they do not expressly or imply that the devices or elements described necessarily have a particular orientation or are configured or operated in a particular orientation.

[0018] In the description of this application, it should be explained that the term "connection" should be understood in a broad sense unless otherwise clearly specified or limited. For example, it may be fixedly connected, detachably connected, or integrally connected. It may be mechanically connected or electrically connected. It may be directly connected, or may be indirectly connected via an intermediate medium, or the insides of two elements may be communicated. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific situation.

[0019] The embodiment of the present application relates to an image sensor, which, as a component of a photographing module, is used to detect optical signals, convert the optical signals into electrical signals for output, and form image data.

[0020] Hereinafter, the structure of an image sensor according to an embodiment of the present application will be described with reference to FIGS.

[0021] As shown in Figures 1 and 2, an image sensor 10 according to some embodiments of the present application includes a number of pixel units 11. These pixel units 11 are arranged according to a set rule to form a pixel array, for example, the pixel array sequentially includes an R pixel unit 11a, a G pixel unit 11b, a B pixel unit 11c, etc. In this embodiment, one pixel unit 11 of the image sensor 10 corresponds to one pixel point of the image to be collected, for example, the R pixel unit 11a corresponds to one pixel point of the image to be collected, the G pixel unit 11b corresponds to one pixel point of the image to be collected, and the B pixel unit 11c corresponds to one pixel point of the image to be collected.

[0022] 3, one pixel unit in the image sensor includes a photosensitive element 1111, which is a photodiode, and the photodiode may be any one of a red photodiode, a green photodiode and a blue photodiode. The red photodiode is used to detect a red (Red, R) light signal, the green photodiode is used to detect a green (Green, G) light signal, and the blue photodiode is used to detect a blue (Blue, B) light signal.

[0023] For example, as shown in Figure 2, the pixel units are arranged according to a set rule to form a general RGB pixel array, where the RGB pixel array may include a red photosensitive element R, a green photosensitive element G, and a blue photosensitive element B. The RGB pixel array may be a Bayer pixel array.

[0024] The imaging module shown in Fig. 4 is a complementary metal oxide semiconductor (CMOS) imaging module. The general operation flow of the CMOS imaging module is to detect optical signals by a large number of photodiodes and convert them into electrical signals, which are amplified by an amplifier circuit and then analog-to-digital converted by an analog-to-digital conversion circuit to form a digital signal matrix (i.e., an image). In the embodiment of the present application, the imaging module adopts a rolling shutter exposure, that is, the pixel array in the image sensor is exposed in a progressive scan manner until all pixel units are exposed.

[0025] 3, the image sensor includes a reset switch 1116 and a signal control circuit. The signal control circuit includes a voltage logic judgment module 1115 and a logic control module 1118.

[0026] Here, the voltage logic judgment module 1115 has a first terminal connected to the first terminal of the photosensitive element 1111 and a second terminal connected to the second terminal of the photosensitive element 1111, and when the voltage logic judgment module 1115 detects that the voltage difference between both ends of the photosensitive element 1111 reaches a preset voltage threshold, it is used to output an automatic control signal for controlling the reset switch 1116 to be on so that the electrons in the photosensitive element 1111 are empty, and to output a counting signal.

[0027] The logic control module 1118 has a first input terminal connected to the first terminal of the voltage logic judgment module 1115 and an output terminal connected to the reset switch 1116, a first input terminal of the logic control module 1118 is used for receiving a counting signal, and a second input terminal of the logic control module 1118 is used for receiving a control signal, and the logic control module 1118 is used to control the reset switch 1116 to be on so that the electrons in the photosensitive element 1111 are in an empty state when the control signal meets a preset condition, for example, when the logic control module 1118 receives a forced control signal, it can control the reset switch 1116 to be on so that the electrons in the photosensitive element 1111 are in an empty state.

[0028] As shown in FIG. 3, the signal control circuit further includes a first switch 1114, and the photosensitive element 1111 and the first switch 1114 are connected in series between a signal terminal Vs and a ground terminal GND.

[0029] As shown in Fig. 4, the count module outputs the count signal, and in this embodiment, a reset switch and a signal control circuit may be provided corresponding to each pixel unit 11 in the pixel array of the image sensor, or a reset switch and a signal control circuit may be provided corresponding to any one or more pixel units 11 in the pixel array. For example, a reset switch and a signal control circuit may be provided corresponding to the pixel unit 11 represented by the gray box in Fig. 4, and a reset switch and a signal control circuit may not be provided corresponding to the other pixel units other than the pixel unit 11 represented by the gray box. Of course, a reset switch and a signal control circuit may be provided corresponding to all pixel units in Fig. 4.

[0030] In this embodiment, for each sampling time in the exposure time, when the voltage difference between both ends of the photosensitive element 1111 reaches the preset voltage threshold, the voltage logic judgment module 1115 outputs an automatic control signal to control the reset switch 1116 to be on, so that the electrons in the photosensitive element 1111 are in an empty state, and outputs a count signal to the first input terminal of the logic control module 1118 to perform one count. When the control signal meets a preset condition, the logic control module 1118 controls the reset switch 1116 to be on, so that the electrons in the photosensitive element 1111 are in an empty state. Here, the preset condition may be that the received control signal is a forced control signal. In this way, all the brightness information of the photosensitive element 1111 in the exposure time can be obtained based on the number of count signals of the photosensitive element 1111 at the end of the exposure time.

[0031] The preset voltage threshold may be the maximum voltage that the photosensitive element 1111 can withstand, may be half the maximum voltage that the photosensitive element 1111 can withstand, or may be another value, and this embodiment is not limited thereto. For example, the exposure parameters are 1000 lux light exposure for 1 ms, and the maximum voltage that the photosensitive element 1111 can withstand is 10V, in this case, the preset voltage threshold may be 10V or any value less than 10V, for example, the preset voltage threshold may be 5V.

[0032] For example, when a forced control signal is received, the automatic control signal is blocked by the logic control module 1118. Take the exposure time as an example of 100 ms, when the logic control module 1118 receives the forced control signal, it can control the reset switch 1116 to be on when the exposure time is 50 ms, so that the photosensitive element 1111 is in an empty state, thereby achieving the purpose of exposing the pixel unit for 50 ms.

[0033] For example, the exposure time of 1000 lux light is set as the exposure parameter to 1 ms, the maximum voltage that the photosensitive element 1111 can withstand is 10V, and the preset voltage threshold is 5V. In this case, if the ambient light intensity is 2000 lux, the following may be used: At the time of 0.25 ms in the exposure time, the voltage difference between both ends of the photosensitive element 1111 reaches the preset voltage threshold, that is, the voltage difference between both ends of the photosensitive element 1111 becomes 5V. At this time, the voltage logic judgment module 1115 controls the reset switch 1116 to turn on to empty the photosensitive electrons in the photosensitive element 1111, and starts exposure again, and outputs a count signal to perform one count, where i=0+1.

[0034] At the time of 0.5 ms during the exposure time, the voltage difference across the photosensitive element 1111 again reaches the preset voltage threshold, that is, the voltage difference across the photosensitive element 1111 becomes 5V. At this time, the voltage logic judgment module 1115 controls the reset switch 1116 to turn on to empty the photosensitive electrons in the photosensitive element 1111, and starts exposure again, and outputs a count signal to count again, in this case, i=0+1+1=2.

[0035] At the time of 0.75 ms during the exposure time, the voltage difference across the photosensitive element 1111 again reaches the preset voltage threshold, that is, the voltage difference across the photosensitive element 1111 is 5V. At this time, the voltage logic judgment module 1115 controls the reset switch 1116 to turn on to empty the photosensitive electrons in the photosensitive element 1111, and starts exposure again, and controls the count signal to count once, in this case, i=0+1+1+1=3.

[0036] At the end time of the exposure time of 1 ms, based on the luminance information 1024 of the photosensitive element 1111 at the end of the exposure time of 1 ms and the count value 3*1024, the luminance information of the photosensitive element 1111 within the exposure time of 1 ms, which is 4096, can be obtained. That is, during one exposure time in a scene with a high luminance ratio, the luminance information that can be obtained by the photosensitive element 1111 is 4096, and all the luminance information in a backlight shooting scene or a scene with a high luminance ratio is obtained, thus avoiding the situation of overexposure, realizing the high dynamic photosensitive function of the pixel unit, and improving the image quality level of the final photo and the user experience.

[0037] Exemplarily, the photosensitive element 1111 is a photodiode and the reset switch 1116 is a CMOS switch.

[0038] 3, the image sensor 10 may further include an electric energy storage module 112, which is also connected between the signal terminal Vs and the ground terminal GND. The electric energy storage module 112 includes a capacitor, which can store the electric energy discharged from the photosensitive element 1111 for reading.

[0039] In this embodiment, taking one pixel unit of the image sensor as an example, the photosensitive element 1111 of the pixel unit obtains the light energy of the detected color after one exposure, converts the light energy into electrical energy and stores it in the photosensitive element 1111. When the pixel unit is selected to read the electrical signal of the pixel unit, the first switch 1114 of these photosensitive elements 1111 is controlled to be turned on, and the corresponding photosensitive element 1111 can release electrical energy to the electrical energy storage module 112 for reading.

[0040] For example, taking one R pixel unit 11a of the image sensor as an example, when the image sensor completes one exposure and selects the R pixel unit 11a to read, the first switch 1114 connected in series with the photosensitive element 1111 can be controlled to be turned on. At this time, the photosensitive element 1111 converts the red light energy to obtain electrical energy, which can be transferred to the electrical energy storage module 112 for reading.

[0041] In some embodiments, in order to facilitate time-division reading of the electrical signals converted by different photosensitive elements 1111, as shown in Fig. 3, the signal control circuit may further include a reset switch RST1, which is connected between the power supply terminal VDD and the signal terminal Vs. In this embodiment, the reset switch RST1 can be controlled to be off to read the photosensitive element 1111 of the pixel unit, and after completing the reading of the photosensitive element 1111, the reset switch RST1 can be controlled to be on to reset the photosensitive element 1111.

[0042] In some embodiments, as shown in FIG. 3, the signal control circuit may further include a source follower SF and a selection switch SET, where the gate of the source follower SF is connected to the signal end Vs, the drain of the source follower SF is connected to the power supply end VDD3, and the selection switch SET is connected between the source of the source follower SF and the output end Vout of the signal control circuit.

[0043] In this embodiment, the source follower SF can amplify the electrical signal at the signal end Vs to improve the accuracy of signal collection. In this embodiment, the selection switch SET can select a pixel unit to be scanned each time when scanning the image sensor, and the selection switch SET can be a row selection switch or a column selection switch as necessary, and is not limited here.

[0044] For example, as shown in FIG. 4, the selection switch SET is a row selection switch, which can select a pixel unit to be scanned each time.

[0045] The switches in the above embodiment include a first switch 1114, a reset switch 1116, a selection switch SET, a source follower SF, etc., and may be complementary metal-oxide semiconductor (CMOS) switches or other types of switches, and are not limited here.

[0046] Next, the exposure process provided in the embodiments of the present application will be described with reference to FIG. 3 as an example, and the exposure process is as follows:

[0047] In step 202, the switch transistor RST1 and the first switch 1114 are turned on, a voltage is applied to the negative electrode of the photosensitive element 1111 and the electrical energy storage module 112, the photosensitive element 1111 is reverse biased, and the electrons in the photosensitive element 1111 and the electrical energy storage module 112 are emptied back to zero.

[0048] In step 204, the switch transistor RST1 and the first switch 1114 are turned off, the photosensitive element 1111 starts to be exposed to light and store energy (corresponding to the exposure start time), and a voltage difference starts to occur across the two ends.

[0049] In step 205, the voltage logic judgment module sends a reset signal to the control end of the reset switch 1116, turns on the reset switch 1116 once, thereby resetting the photoelectrons in the photosensitive element 1111, restarting the photosensitivity and energy storage from zero (corresponding to the reset time), and a voltage difference begins to occur between both ends; at the same time, the voltage logic judgment module 1115 sends a count signal to the logic control module 1118, counts once, or when the logic control module receives a forced control signal, controls the reset switch 1116 to be turned on once, thereby resetting the photoelectrons in the photosensitive element 1111, restarting the photosensitivity and energy storage from zero (corresponding to the reset time), and a voltage difference begins to occur between both ends.

[0050] In step 206, the switch transistor RST1 is turned on to drain the electrical energy storage module 112 again and avoid interference / coupling with current electrons occurring in the electronic circuit.

[0051] In step 208, the switch transistor RST1 is turned off, the first switch 1114 is turned on, and the switch transistor SET is turned on (corresponding to the end of exposure time), so that the energy of the photosensitive element 1111 is stored in the electrical energy storage module 112, and the Vout terminal outputs a voltage signal to the column amplifier corresponding to the pixel unit.

[0052] Finally, the voltage output from the Vout terminal is a voltage signal converted from the optical signal detected by the photosensitive element 1111 from the reset time to the end of exposure.

[0053] In an embodiment of the present application, the image sensor includes a photosensitive element, a reset switch and a signal control circuit, the signal control circuit includes a voltage logic judgment module and a logic control module. The voltage logic judgment module has a first end connected to a first end of the photosensitive element and a second end connected to a second end of the photosensitive element, the voltage logic judgment module is used to output an automatic control signal for controlling the reset switch to be on so that the electrons in the photosensitive element are empty when it detects that the voltage difference between both ends of the photosensitive element reaches a preset voltage threshold, and is used to output a count signal to a first input end of the logic control module. The logic control module has a first input end connected to the first end of the voltage logic judgment module and an output end connected to the reset switch, the first input end of the logic control module is used to receive the count signal, and the second input end of the logic control module is used to receive the control signal, the logic control module is used to control the reset switch to be on so that the electrons in the photosensitive element are empty when the control signal meets a preset condition. In this way, the logic control module is provided to control the reset switch, and the voltage logic judgment module can output a counting signal, so that after the exposure is completed, the photosensitive signal of the photosensitive element can be accurately obtained, and the situation of overexposure and underexposure can be avoided, so that the high dynamic photosensitive function of the pixel unit can be realized, and the image quality level can be improved.

[0054] As shown in FIG. 5, an embodiment of the present application further provides an exposure control method, which is applied to the image sensor described in the above embodiments.

[0055] The exposure control method of this embodiment may include the following steps 301 to 303.

[0056] In step 301, a preset brightness of a first image, and a first partition brightness and a first exposure amount corresponding to each image region of the first image are obtained.

[0057] In step 302, a second exposure amount corresponding to each of the image regions is obtained based on the preset brightness, a first partition brightness corresponding to each of the image regions, and a first exposure amount.

[0058] In step 303, a second image collected by the image sensor is exposed according to a second exposure amount corresponding to each of the image areas.

[0059] For example, the first image is divided into 8*8 image regions in advance, and each image region corresponds to one first division brightness and one first exposure amount. pre (i,j)=Σ each pixel (0.299*R+0.587*G+0.114*B) is the first block luminance Y corresponding to each image area. pre (i,j) can be calculated, where R is the red light sensitive signal value, G is the green light sensitive signal value, and B is the blue light sensitive signal value, and (i,j) represents the image area.

[0060] Assuming that the scene brightness does not change when capturing two frames of images (the time interval is short), the formula M cur (i,j)=Y target *M pre (i,j) / Y pre (i, j) to obtain the second exposure dose M cur (i,j) can be obtained, where Y target represents the preset brightness, and M pre represents the first exposure dose.

[0061] In practical application, for each image area of ​​the first image, the above operation of obtaining the preset brightness of the first image, and the first division brightness and first exposure corresponding to each image area of ​​the first image can be performed until the second exposure of each image area is obtained, and when the image sensor is controlled to expose the first image, it is exposed according to the second exposure corresponding to each image area, and a digital signal is output to form a raw image and output to an image processing system.

[0062] It should be noted that when the camera is turned on, the above steps 301 to 303 are repeated until the camera is turned off.

[0063] In one embodiment, the image region can include a foreground image region and a background image region, that is, the partition of the pixel unit is adaptively realized according to the foreground and background of the first image, and has better adaptability to the shooting scene.

[0064] Specifically, in this embodiment, the principle of dividing the foreground image region and the background image region of the first image is to extract the partition threshold value by the maximum inter-class variance method to divide the gray scale value of the image.

[0065] Specifically, a gray scale value corresponding to each pixel unit of the first image is obtained, and according to a comparison result between the gray scale value and a preset gray scale threshold T, the pixel unit can be divided into a first class of pixel units C1 and a second class of pixel units C2, where the gray scale value of the first class of pixel units C1 is smaller than the preset gray scale threshold T, and the gray scale value of the second class of pixel units C2 is larger than the preset gray scale threshold T.

[0066] a first gradation value average value m1 of the first class pixel unit, a second gradation value average value m2 of the second class pixel unit, a first probability p1 of the first class pixel unit, and a second probability p2 of the second class pixel unit; a partition threshold Tmax is obtained based on the first gradation value average value m1, the second gradation value average value m2, the first probability p1, and the second probability p2; and a target pixel partition of a target pixel unit in the pixel array is determined based on the partition threshold Tmax.

[0067] Specifically, after obtaining the first gradation value average value m1 of the first class pixel unit, the second gradation value average value m2 of the second class pixel unit, and the first probability p1 of the first class pixel unit and the second probability p2 of the second class pixel unit, the global average value mG can be obtained by the formula p1*m1+p2*m2=mG, where p1+p2=1.

[0068] The between-class variance is given by the formula σ ^2 =p1(m1-mG) ^2 +p2(m2-mG) ^2 By simplifying the formula for the inter-class variance, that is, by substituting p1*m1+p2*m2=mG into the formula for the inter-class variance, the final formula for the inter-class variance is σ ^2 =p1p2(m1-m2) ^2 can be obtained.

[0069] It should be noted that the value of T in the calculation process is 0 to 255, and in this embodiment, all values ​​of T are taken to obtain 256 inter-class variances, of which the maximum value is taken as the partition threshold Tmax in this embodiment, and then the foreground image area and background image area of ​​the first image are determined based on the partition threshold Tmax.

[0070] After acquiring the foreground image area and background image area of ​​the first image, steps 301 to 303 are performed to acquire second exposure amounts corresponding to the foreground image area and background image area, and when the image sensor is controlled to expose the first image, it exposes according to the second exposure amount corresponding to each image area, outputs a digital signal to form a raw image, and outputs it to an image processing system.

[0071] In this embodiment, by performing differential exposure for each image area, the exposure precision can be increased, and the image quality level can be further improved.

[0072] As shown in FIG. 6, an embodiment of the present application further provides a photographing module 600, which includes an image sensor 10, which may be the image sensor 10 according to any of the above embodiments.

[0073] In some embodiments, the photographing module 600 further includes a lens 620 and a circuit board 630, the image sensor 10 is electrically connected to the circuit board 630, and the circuit board 630 can be provided with a signal processing unit and an analog-to-digital converter, etc., so that the analog electrical signal output from the image sensor 10 is converted into a digital signal by the analog-to-digital converter, and the digital signal is output to the signal processing unit for signal processing to further obtain image data. The lens 620 is provided on the opposite side of the image sensor 10 to the circuit board 630, i.e., the light incident surface of the image sensor 10 faces the lens 620.

[0074] In some embodiments, in order to improve the shooting performance of the shooting module 600, the shooting module 600 may further include an optical filter 640, which is disposed between the image sensor 10 and the lens 620, and is used to filter out infrared light and the like that is invisible to the human eye during daytime shooting, thereby increasing the effective resolution and color reproducibility of the collected image, and further improving the quality of the collected image.

[0075] In some embodiments, the imaging module 600 may further include a motor 650 , which is connected to the lens 620 and is used to drive the movement of the lens 620 .

[0076] In some embodiments, the photography module 600 can achieve auto-zoom by controlling the motor 650 to drive the movement of the lens 620 .

[0077] In some embodiments, to facilitate mounting of the motor 650, the imaging module 600 may further include a base 660 for mounting the motor 650.

[0078] In some embodiments, the photographing module 600 may further include a protective film 670 disposed on the lens 620 to protect the lens 620 from damage.

[0079] In the photographing module 600 of this embodiment, no multi-frame synthesis is required, and all information of a scene with a high light intensity ratio can be obtained with only one exposure of the image sensor, which can effectively improve the image quality level of the photographing and further improve the image quality.

[0080] An embodiment of the present application further provides an electronic device, which includes the photographing module according to any of the above embodiments.

[0081] For example, the electronic device includes a housing, the housing having a light-transmitting portion, and the photographing module may be disposed within the housing of the electronic device, with a lens of the photographing module facing the light-transmitting portion so that an image can be collected by the light-transmitting portion.

[0082] The electronic device may be any device with a photographing function, such as a mobile phone, a tablet computer, a notebook computer, a wearable device, etc., and is not limited thereto.

[0083] Although the above embodiments have been described with a focus on the differences between the corresponding embodiments and other embodiments, the same or similar parts of each embodiment may be mutually referenced.

[0084] In the description herein, a description using the terms "one embodiment," "some embodiments," "exemplary embodiments," "example," "particular examples," or "some examples" means that the specific feature, structure, material, or characteristic described based on the embodiment or example is included in at least one embodiment or example of the present application. In the description herein, exemplary descriptions of the above terms are not necessarily all for the same embodiment or example. And, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0085] Although the embodiments of the present application have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present application, and the scope of the present application is limited by the claims and their equivalents. [Explanation of symbols]

[0086] 10 Image Sensor 11 Pixel Unit 11a R pixel unit 11b G pixel unit 11c B pixel unit 1111 Photosensitive element 1114 First Switch 1115 Voltage logic judgment module 1116 Reset Switch 1118 Logic Control Module 112 Electrical Energy Storage Module Vs signal end VDD power supply terminal GND grounding end RST Reset switch SF Source Follower SET selection switch Vout signal output terminal 600 Imaging Module 620 Lens 630 Circuit Board 640 Optical Filter 650 Motor 660 Base 670 Protective Film

Claims

1. An image sensor including a photosensitive element, a reset switch, and a signal control circuit, the signal control circuit including a voltage logic judgment module and a logic control module; the voltage logic judgment module has a first end connected to a first end of the photosensitive element and a second end connected to a second end of the photosensitive element, and is used for outputting an automatic control signal for controlling the reset switch to be on, so that the electrons in the photosensitive element are empty, and outputting a count signal to a first input end of the logic control module when the voltage logic judgment module detects that a voltage difference between both ends of the photosensitive element reaches a preset voltage threshold; the logic control module has a first input terminal connected to a first terminal of the voltage logic judgment module and an output terminal connected to the reset switch, the first input terminal of the logic control module is used for receiving the count signal, and the second input terminal of the logic control module is used for receiving a control signal, and the logic control module is used for controlling the reset switch to be on, so that the electrons in the photosensitive element are emptied when the control signal meets a preset condition.

2. the signal control circuit further includes a first switch; 2. The image sensor according to claim 1, wherein the photosensitive element and the first switch are connected in series between a signal terminal and a ground terminal.

3. The image sensor of claim 1 , wherein the signal control circuit further includes an electrical energy storage module, the electrical energy storage module being connected between a signal end and a ground end.

4. The image sensor of claim 3 , wherein the electrical energy storage module includes a capacitor.

5. The image sensor according to claim 1 , wherein the signal control circuit further includes a reset switch, the reset switch being connected between a power supply terminal and a signal terminal.

6. 2. The image sensor of claim 1, wherein the signal control circuit further includes a source follower and a selection switch, the source follower having a gate connected to a signal end and a drain connected to a power supply end, and the selection switch is connected between a source of the source follower and an output end of the signal control circuit.

7. An exposure control method applied to the image sensor according to any one of claims 1 to 6, comprising: obtaining a preset brightness of a first image, and a first partition brightness corresponding to each image region of the first image, and a first exposure dose; obtaining a second exposure amount corresponding to each of the image regions according to the preset brightness, a first partition brightness corresponding to each of the image regions, and a first exposure amount; and exposing a second image captured by the image sensor according to a second exposure amount corresponding to each of the image areas.

8. The method of claim 7 , wherein the image regions include a foreground image region and a background image region.

9. An imaging module comprising the image sensor according to any one of claims 1 to 6.

10. a circuit board electrically connected to the image sensor; a lens provided on an opposite side of the image sensor to the circuit board; The imaging module of claim 9 , further comprising:

11. An electronic device comprising the imaging module according to claim 9 or 10.

Images