Image sensor and electronic device

Abstract

The present application provides an image sensor and an electronic device, the image sensor comprising: a pixel array, the pixel array comprising a plurality of pixel regions arranged in an array, each pixel region comprising a pixel circuit, and at least one pixel region comprising a flicker detection circuit; and the exposure control module is electrically connected with the flicker detection circuit and is used for determining the flicker frequency of the flicker light source according to the flicker signal output by the flicker detection circuit and controlling the exposure duration of the pixel circuit according to the flicker frequency. According to the invention, the fusion of the image sensor and the Flicker sensor is realized, the cost of the camera system is reduced, and the detection error of the flicker light source is reduced.

Description

Technical Field

[0001] This application relates to the field of imaging technology, and more particularly to an image sensor and an electronic device. Background Art

[0002] Currently, there may be a phenomenon of a flickering light source during the photographing process of a camera module. For example, the flickering light source may include ambient light in the scene (such as an AC fluorescent lamp), and for another example, the flickering light source may include the object itself being photographed (such as a computer screen). In order to ensure that the photographing effect of the camera module is not affected by the flickering light source, it is usually necessary to set a sensor (Flicker sensor) for detecting the flickering frequency of the flickering light source. After detecting the flickering frequency of the flickering light source, the camera module is guided to set a reasonable exposure duration according to the flickering frequency of the flickering light source, thereby avoiding the influence of the flickering light source during the photographing process.

[0003] However, in the related art, the Flicker sensor is usually separated from the image sensor, which results in a large difference in the field of view between the Flicker sensor and the image sensor during shooting. As a result, the flickering frequency of the flickering light source detected by the Flicker sensor is actually different from the flickering frequency of the flickering light source received by the image sensor. Finally, after changing the exposure duration of the camera module, there is still a phenomenon that the camera module is affected by the flickering light source. Summary of the Invention

[0004] This application provides an image sensor and an electronic device, aiming to solve the above technical problems.

[0005] In a first aspect, this application provides an image sensor, including:

[0006] A pixel array, the pixel array includes a plurality of pixel regions arranged in an array, each pixel region includes a pixel circuit, and at least one pixel region includes a flicker detection circuit;

[0007] An exposure control module, the exposure control module is electrically connected to the flicker detection circuit, and is configured to determine the flickering frequency of the flickering light source according to the flicker signal output by the flicker detection circuit, and control the exposure duration of the pixel circuit according to the flickering frequency.

[0008] In some embodiments, the pixel circuit includes a first photodiode for generating a first photocurrent, and the flicker detection circuit includes a second photodiode for generating a second photocurrent;

[0009] Wherein, the pixel circuit outputs an image signal according to the first photocurrent output by the first photodiode, and the second photocurrent output by the second photodiode is used as the flicker signal.

[0010] In some embodiments, the size of the second photodiode is smaller than the size of the first photodiode.

[0011] In some embodiments, the exposure control module includes a flash driving unit, a flash reading unit, and a processing unit;

[0012] The flash driving unit is connected to each flash detection circuit, and is configured to control the exposure of the flash detection circuit and output a flash signal;

[0013] The flash reading unit is connected to the flash detection circuit, and is configured to read the flash signal output by the flash detection circuit to obtain flash data;

[0014] The processing unit is configured to determine the flash frequency of the flash light source according to the flash data, and control the exposure duration of the pixel circuit according to the flash frequency.

[0015] In some embodiments, the N pixel regions include flash detection circuits, the flash reading unit includes at least one signal conversion subunit and at least one reading subunit, and the signal conversion subunits and the reading subunits correspond to each other one by one;

[0016] The signal conversion subunit is configured to receive the second photo-generated current output by the flash detection circuits of the M pixel regions, and output a flash voltage signal based on the second photo-generated current output by the flash detection circuits of the M pixel regions;

[0017] The reading subunit is configured to read the flash voltage signal to obtain flash data;

[0018] Wherein, M is less than or equal to N, and M is an integer greater than 1.

[0019] In some embodiments, the signal conversion subunit includes an operational amplifier, a reset switch, and an integration capacitor;

[0020] A first input terminal of the operational amplifier is connected to a preset reference voltage, a second input terminal of the operational amplifier is connected to each flash detection circuit to access the second photo-generated current, and an output terminal of the operational amplifier is connected to the reading subunit to output a flash voltage signal to the reading subunit;

[0021] A first end of the integration capacitor is connected to the second input terminal of the operational amplifier, and a second end of the integration capacitor is connected to the output terminal of the operational amplifier;

[0022] A first end of the reset switch is connected to the second input terminal of the operational amplifier, and a second end of the reset switch is connected to the output terminal of the operational amplifier.

[0023] In some embodiments, the reading subunit includes an analog-to-digital converter, and an input terminal of the analog-to-digital converter is connected to the output terminal of the operational amplifier.

[0024] In some embodiments, the N pixel regions including flash detection circuits are arranged around the center of the pixel array; or

[0025] N pixel regions each including a scintillation detection circuit are arranged in the same column; or

[0026] N pixel regions each including a scintillation detection circuit are arranged in the same row.

[0027] In some embodiments, the pixel circuit further includes a first transfer subunit and a first output subunit;

[0028] The first transfer subunit is configured to control the conduction and cutoff between the first photodiode and the first floating diffusion node, so that the first floating diffusion node generates a first photosensitive signal related to the light intensity based on the first photocurrent;

[0029] The first output subunit is configured to output an image signal according to the first photosensitive signal of the first floating diffusion node.

[0030] In some embodiments, the first transfer subunit includes a first transistor, and the first output subunit includes a first reset transistor, a first amplifying transistor, and a first output transistor;

[0031] The first end of the first transistor is connected to the first photodiode, the second end of the first transistor is connected to the first floating diffusion node, and the control end of the first transistor is connected to the row driving unit to access an image exposure signal;

[0032] The first end of the first reset transistor is connected to the power supply terminal, the second end of the first reset transistor is connected to the first floating diffusion node, and the control end of the first reset transistor is configured to access a first reset signal;

[0033] The first end of the first amplifying transistor is connected to the power supply terminal, the control end of the first amplifying transistor is connected to the first floating diffusion node, and the second end of the first amplifying transistor is connected to the first end of the first output transistor;

[0034] The control end of the first output transistor is connected to the row driving unit to access a first scan signal, and the second end of the first output transistor is connected to the column reading unit to output an image signal to the column reading unit.

[0035] In some embodiments, the scintillation detection circuit further includes a second transfer subunit;

[0036] The second transfer subunit is configured to control the second photodiode to output a second photocurrent.

[0037] In some embodiments, the second transfer subunit includes a second transistor;

[0038] The first end of the second transistor is connected to the second photodiode, the control end of the second transistor is connected to the scintillation driving unit to access a scintillation exposure signal, and the second end of the second transistor is connected to the scintillation reading unit to output a scintillation signal to the scintillation reading unit.

[0039] In a second aspect, the present application provides an electronic device, including the image sensor as described in the first aspect.

[0040] In the present application, a flicker detection circuit is provided in at least one pixel region. The exposure control module determines the flicker frequency of the flicker light source according to the flicker signal output by the flicker detection circuit, and controls the exposure duration of the pixel circuit according to the flicker frequency. That is to say, the integration of the image sensor and the Flicker sensor in the present application not only helps to reduce the cost of the imaging system, but also when the image sensor including the pixel circuit of the present application acquires an image, the flicker frequency of the flicker light source, that is, the flicker frequency of the flicker light source in the shooting scene, can be detected. Therefore, it is also possible to avoid the phenomenon that the flicker frequency of the flicker light source detected by the Flicker sensor is different from the flicker frequency of the flicker light source received by the image sensor due to the separation of the Flicker sensor and the image sensor. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the following drawings are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative efforts.

[0042] Figure 1 Shows a schematic structural diagram of an image sensor in an embodiment of the present application;

[0043] Figure 2 Shows a schematic diagram of a pixel circuit and a flicker detection circuit in an embodiment of the present application;

[0044] Figure 3 Shows another schematic diagram of a pixel circuit and a flicker detection circuit in an embodiment of the present application;

[0045] Figure 4 Shows another schematic diagram of a pixel circuit and a flicker detection circuit in an embodiment of the present application;

[0046] Figure 5 Shows another schematic diagram of a pixel circuit and a flicker detection circuit in an embodiment of the present application;

[0047] Figure 6 Is a schematic diagram of a flicker reading unit and a flicker detection circuit provided in an embodiment of the present application;

[0048] Figure 7 Is a schematic diagram of a pixel array provided in an embodiment of the present application;

[0049] Figure 8It is another schematic diagram of the pixel array provided in the embodiment of the present application;

[0050] Figure 9 It is another schematic diagram of the pixel array provided in the embodiment of the present application;

[0051] Figure 10 It is another schematic diagram of the scintillation reading unit and the scintillation detection circuit provided in the embodiment of the present application;

[0052] Figure 11 It is another schematic diagram of the scintillation reading unit and the scintillation detection circuit provided in the embodiment of the present application.

[0053] Among them, 1 is the exposure control module, 100 is the pixel array, 200 is the row driving unit, 300 is the column reading unit, 400 is the scintillation driving unit, 500 is the scintillation reading unit, 501 is the signal conversion sub-unit, 502 is the reading sub-unit, and 600 is the processing unit;

[0054] 10 is the pixel area, 11 is the pixel circuit, 111 is the first transmission sub-unit, 112 is the first output sub-unit, 12 is the scintillation detection circuit, and 121 is the second transmission sub-unit;

[0055] The first photodiode PD1, the second photodiode PD2, the first floating diffusion node FD1, the first photosensitive signal VPD1, and the scintillation voltage signal Vfs;

[0056] The first transistor M1, the second transistor M2, the first reset transistor Ms1, the first amplification transistor Ma1, the first output transistor Mo1, the second reset transistor Ms2, the second amplification transistor Ma2, the second output transistor Mo2, the operational amplifier OP, the integration capacitor CI, and the reset switch SI;

[0057] The image exposure signal TX1, the scintillation exposure signal TX2, the first reset signal RST1, the second reset signal RST2, the first scan signal SD2, and the second scan signal SD2. Detailed implementation manners

[0058] Next, the technical solutions in the embodiments of the present application will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative efforts belong to the scope of protection of the present invention.

[0059] In the description of the present invention, the term "exemplary" is used to mean "serving as an example, illustration, or explanation". Any embodiment described as "exemplary" in this application is not necessarily to be construed as more preferred or advantageous than other embodiments. The following description is provided to enable any person skilled in the art to make and use the present invention. In the following description, details are set forth for the purpose of explanation. It should be understood that those of ordinary skill in the art can recognize that the present invention can be implemented without these specific details. In other instances, well-known structures and processes are not elaborated in detail to avoid obscuring the description of the present invention with unnecessary details. Therefore, the present invention is not intended to be limited to the embodiments shown, but is to be accorded the widest scope consistent with the principles and features disclosed in this application.

[0060] Embodiments of the present application provide an image sensor and an electronic device, which are described in detail below respectively.

[0061] First, refer to Figure 1 , Figure 1 which shows a schematic structural diagram of an image sensor in an embodiment of the present application. Among them, the image sensor includes a pixel array 100 and an exposure control module 1.

[0062] Specifically, the pixel array 100 includes a plurality of pixel regions 10 arranged in an array. Each pixel region 10 includes a pixel circuit 11. The pixel circuit 11 can sense the light reflected or emitted by an object (i.e., the target to be photographed) and generate an image signal. After the column reading unit 300 reads the image signal to obtain image data, the processing unit 600 generates a frame of image or stores the image data according to the image data. Among them, at least one pixel region 10 among the plurality of pixel regions 10 includes a flicker detection circuit 12. The flicker detection circuit 12 can sense the light emitted by the flicker light source and output a flicker signal. After the flicker reading unit 500 reads the flicker signal to obtain flicker data, the processing unit 600 determines the flicker frequency of the flicker light source according to the flicker data.

[0063] The exposure control module 1 is electrically connected to the flicker detection circuit 12. The exposure control module 1 can be used to determine the flicker frequency of the flicker light source according to the flicker signal output by the flicker detection circuit, and control the exposure duration of the pixel circuit according to the flicker frequency. Generally, the exposure control module 1 includes a flicker driving unit 400, a flicker reading unit 500, and a processing unit 600, so as to control the exposure of the flicker detection circuit 12 through the flicker driving unit 400 and output a flicker signal, read the flicker signal output by the flicker detection circuit 12 through the flicker reading unit 500 to obtain flicker data, and finally determine the flicker frequency of the flicker light source through the processing unit 600 and control the exposure duration of the pixel circuit.

[0064] In some embodiments of the present application, the exposure control module 1 further includes a row driving unit 200 and a column reading unit 300, so as to control each row of pixel circuits 11 through the row driving unit 200 and read the image signals output by each column of pixel circuits 11 through the column reading unit 300.

[0065] Among them, the row driving unit 200 is connected to each row of pixel circuits 11 through row scan lines to control each row of pixel circuits 11. For example, the row driving unit 200 can control whether each row of pixel circuits 11 outputs an image signal through the row scan lines; for another example, the row driving unit 200 can control whether each row of pixel circuits 11 is exposed through the row scan lines; for still another example, the row driving unit 200 can control whether each row of pixel circuits 11 is reset through the row scan lines.

[0066] The column reading unit 300 is connected to each column of pixel circuits 11 through column reading lines to read the image signals output by each column of pixel circuits 11. For example, when the row driving unit 200 controls the Nth row of pixel circuits 11 to output an image signal, the column reading unit 300 reads the image signals output by each pixel circuit 11 in the Nth row through the column reading lines, so as to obtain the image data corresponding to the pixel units in the Nth row; for another example, when the row driving unit 200 controls the (N + 1)th row of pixel circuits 11 to output an image signal, the column reading unit 300 reads the image signals output by each pixel circuit 11 in the (N + 1)th row through the column reading lines, so as to obtain the image data corresponding to the pixel units in the (N + 1)th row.

[0067] Exemplarily, the column reading unit 300 may include an amplifying circuit, an analog-to-digital converter (ADC), a latch circuit or a buffer circuit for temporarily storing digital signals, etc. Among them, the amplifying circuit can amplify the image signal, the analog-to-digital converter can convert the amplified signal of the image signal into a digital signal, and the latch circuit or the buffer circuit can temporarily store the digital signal, so as to facilitate the processing unit 600 to process the digital signal.

[0068] The flash driving unit 400 is connected to each flash detection circuit 12, and the flash driving unit 400 can control the flash detection circuit 12 to be exposed and output a flash signal. In some embodiments of the present application, the flash driving unit 400 can control all flash detection circuits 12 to be exposed simultaneously, that is, the flash detection circuits 12 in all pixel regions 10 are exposed under the control of the same clock signal. In some embodiments of the present application, the flash driving unit 400 can control multiple flash detection circuits 12 to be exposed in sequence. For example, control the flash detection circuits 12 in each row to be exposed in sequence and output a flash signal; for another example, control the flash detection circuits 12 in each column to be exposed in sequence and output a flash signal.

[0069] Exemplarily, the flicker driving unit 400 may include an oscillator (such as an RC oscillator) that generates a clock signal, a PLL (Phase Locked Loop) circuit, a frequency multiplication circuit, or a frequency division circuit, etc., so as to control the flicker detection circuit 12 to perform exposure through the clock signal and output a flicker signal.

[0070] The flicker reading unit 500 is connected to the flicker detection circuit 12, and the flicker reading unit 500 is configured to read the flicker signal output by the flicker detection circuit 12 to obtain flicker data. In some embodiments of the present application, for example, in the embodiment where the flicker driving unit 400 can control all the flicker detection circuits 12 to be exposed simultaneously, the flicker reading unit 500 can simultaneously read the flicker signals output by all the flicker detection circuits 12 to obtain flicker data. In some embodiments of the present application, for example, in the embodiment where the flicker driving unit 400 can control multiple flicker detection circuits 12 to be exposed sequentially, the flicker reading unit 500 can sequentially read the flicker signals output by the multiple flicker detection circuits 12. For example, it can read the flicker signals of the flicker detection circuits 12 in each row pixel region 10 row by row, or for another example, it can read the flicker signals of the flicker detection circuits 12 in each row pixel region 10 column by column.

[0071] Exemplarily, the flicker reading unit 500 may include an amplifier circuit, an analog-to-digital converter (ADC), a latch circuit or a buffer circuit that temporarily stores digital signals, etc. The amplifier circuit can amplify the flicker signal, the analog-to-digital converter can convert the amplified signal of the flicker signal into a digital signal, and the digital signal is temporarily stored through the latch circuit or the buffer circuit.

[0072] The processing unit 600 is connected to the row driving unit 200, the flicker reading unit 500, and the column reading unit 300. The processing unit 600 can process the received data or control the corresponding units. For example, the processing unit 600 can process the image data output from the column reading unit 300, and can output the signal-processed data to a display device, etc., or can store the signal-processed data in a storage device such as a memory; for another example, the processing unit 600 can receive the flicker data output by the flicker reading unit 500, determine the flicker frequency of the flicker light source according to the flicker data, and finally control the row driving unit 200 according to the flicker frequency of the flicker light source, so as to change the exposure duration of the pixel circuit 11 to avoid the influence of the flicker light source on the image quality.

[0073] It can be understood that for those skilled in the art, after understanding the principle of this image sensor, it is possible to make any combination of each module or form a subsystem and connect it to other modules without departing from this principle. For example, Figure 1The driving unit 200, column reading unit 300, flash driving unit 400, flash reading unit 500, and processing unit 600 disclosed in

[0074] In the embodiments of the present application, by arranging a flash detection circuit 12 in at least one pixel region 10, the flash driving unit 400 is used to control the exposure of the flash detection circuit 12 and output a flash signal, so that the flash reading unit 500 can read the flash signal output by the flash detection circuit 12 to obtain flash data, and finally the processing unit 600 can determine the flash frequency of the flash light source according to the flash data. That is to say, the present application realizes the integration of the image sensor and the Flicker sensor, which is not only beneficial to reducing the cost of the camera system, but also when the image sensor including the pixel circuit 11 of the present application acquires an image, the flash frequency of the flash light source, that is, the flash frequency of the flash light source in the shooting scene, can be detected. Therefore, it is also possible to avoid the phenomenon that the flash frequency of the flash light source detected by the Flicker sensor is different from the flash frequency of the flash light source received by the image sensor due to the separation of the Flicker sensor and the image sensor.

[0075] In some embodiments of the present application, the pixel circuit 11 includes a first photodiode PD1 for generating a first photocurrent, and the flash detection circuit 12 includes a second photodiode PD2 for generating a second photocurrent. Among them, the pixel circuit 11 outputs an image signal according to the first photocurrent output by the first photodiode PD1, and the second photocurrent output by the second photodiode PD2 is used as a flash signal.

[0076] It should be noted that the magnitude of the photocurrent generated by the photodiode is positively correlated with its size (such as the light-receiving area). In order to implement exposure control, reset control, and signal output control, the pixel circuit 11 usually includes a control circuit composed of transistors for exposure control, transistors for reset control, and transistors for controlling signal output. Therefore, the area of the pixel circuit 11 is usually large. Setting the flash detection circuit 12 in the same pixel region 10 means that the area of the pixel circuit 11 needs to be reduced to ensure that the flash detection circuit 12 can be accommodated in this pixel region 10. Therefore, generally, the size of the first photodiode PD1 is reduced. Since the size of the first photodiode PD1 is reduced, the number of photons received by the first photodiode PD1 is reduced. Therefore, in the case of low light, it may lead to a decrease in the signal-to-noise ratio of the image signal, and finally cause problems such as deterioration of the image quality or loss of image details.

[0077] In the above embodiments, since the second photocurrent output by the second photodiode PD2 can be directly used as the flicker signal, this means that the flicker detection circuit 12 only needs to be designed with the second photodiode PD2 (or the second photodiode PD2 and a transistor for controlling whether the second photocurrent is output) to be sufficient. Therefore, the area of the flicker detection circuit 12 in the same pixel region is small, which is beneficial to ensuring the area of the pixel circuit 11 and avoiding the problem that the size of the first photodiode PD1 is too small due to the large area occupied by the flicker detection circuit 12, resulting in poor image quality or loss of image details.

[0078] In some embodiments of the present application, the size of the second photodiode PD2 is smaller than that of the first photodiode PD1. Therefore, it is beneficial to reduce the area of the flicker detection circuit 12, thereby further increasing the size of the first photodiode PD1 in the same pixel region 10 to improve the signal-to-noise ratio of the image signal output by the pixel circuit 11.

[0079] In some embodiments of the present application, refer to Figure 2 , Figure 2 shows a schematic diagram of the pixel circuit 11 and the flicker detection circuit 12 in the embodiments of the present application. Among them, the pixel circuit 11 further includes a first transmission subunit 111 and a first output subunit 112; the flicker detection circuit 12 further includes a second transmission subunit 121.

[0080] Specifically, the first transmission subunit 111 is used to control the conduction and cut-off between the first photodiode PD1 and the first floating diffusion node FD1. When the first photodiode PD1 and the first floating diffusion node FD1 are conducted, since the first photodiode PD1 generates a first photocurrent under light, the charge of the first floating diffusion node FD1 is transferred, and the voltage of the first floating diffusion node FD1 changes, so that the first floating diffusion node FD1 generates a first photosensitive signal VPD1 related to the light intensity based on the first photocurrent. After the first floating diffusion node FD1 generates the first photosensitive signal VPD1 related to the light intensity, the first output subunit 112 can output an image signal according to the first photosensitive signal VPD1 of the first floating diffusion node FD1. For example, the first output unit can amplify the first photosensitive signal VPD1 and output it as an image signal.

[0081] The input end of the second transmission subunit 121 is connected to the second photodiode PD2, and the output end of the second transmission subunit 121 is connected to the flash reading unit 500. The second transmission subunit 121 is used to control the second photodiode PD2 to output a second photocurrent. For example, when the second transmission subunit 121 controls the path between the second photodiode PD2 and the flash reading unit 500 to conduct, the flash detection circuit 12 is in an exposure state, and the flash reading unit 500 receives the second photocurrent generated by the second photodiode PD2 and integrates the second photocurrent to generate an integrated voltage; when the second transmission subunit 121 controls the path between the second photodiode PD2 and the flash reading unit 500 to disconnect, the flash reading unit 500 can read the integrated voltage to obtain flash data.

[0082] As an example, refer to Figure 3 , Figure 3 FIG. shows another schematic diagram of the pixel circuit 11 and the flash detection circuit 12 in the embodiment of the present application. Among them, the first transmission subunit 111 includes a first transistor M1, and the first output subunit 112 includes a first reset transistor Ms1, a first amplification transistor Ma1, and a first output transistor Mo1; the first end of the first transistor M1 is connected to the first photodiode PD1, the second end of the first transistor M1 is connected to the first floating diffusion node FD1, and the control end of the first transistor M1 is connected to the row driving unit 200 to access the image exposure signal TX1; the first end of the first reset transistor Ms1 is connected to the power supply terminal, the second end of the first reset transistor Ms1 is connected to the first floating diffusion node FD1, and the control end of the first reset transistor Ms1 is used to access the first reset signal RST1; the first end of the first amplification transistor Ma1 is connected to the power supply terminal, the control end of the first amplification transistor Ma1 is connected to the first floating diffusion node FD1, and the second end of the first amplification transistor Ma1 is connected to the first end of the first output transistor Mo1; the control end of the first output transistor Mo1 is connected to the row driving unit 200 to access the first scan signal SD2, and the second end of the first output transistor Mo1 is connected to the column reading unit 300 to output an image signal to the column reading unit 300.

[0083] For example, taking the first transistor M1, the first reset transistor Ms1, the first amplification transistor Ma1, and the first output transistor Mo1 as NMOS transistors as an example, when the image exposure signal TX1 is at a low level, the first reset signal RST1 is at a high level, and the first scan signal SD2 is at a low level, the first reset transistor Ms1 conducts and the first transistor M1 cuts off, and the pixel circuit 11 is in a reset stage. At this time, the power supply voltage VDD resets and charges the capacitor connected to the first floating diffusion node FD1 to the voltage VDD.

[0084] When the image exposure signal TX1 is at a high level, the first reset signal RST1 is at a low level, and the first scan signal SD2 is at a low level, the pixel circuit 11 is in the exposure stage. The first transistor M1 is turned on while the first reset transistor Ms1 is turned off. The charge of the first floating diffusion node FD1 is transferred through the first photodiode PD1, thereby changing its voltage. Therefore, the first floating diffusion node FD1 can generate a first photosensitive signal VPD1 related to the light intensity based on the first photocurrent.

[0085] When the image exposure signal TX1 is at a low level, the first reset signal RST1 is at a low level, and the first scan signal SD2 is at a high level, the first transistor M1 and the first reset transistor Ms1 are turned off, and the first output transistor Mo1 is turned on. Since the impedance of the first amplification transistor Ma1 is controlled by the first photosensitive signal VPD1, the second terminal of the first amplification transistor Ma1 can output a voltage signal related to the magnitude of the first photosensitive signal VPD1. Finally, after the first output transistor Mo1 is turned on, the second terminal of the first output transistor Mo1 outputs an image signal.

[0086] Continue to refer to Figure 3 , the second transmission subunit 121 includes a second transistor M2. The first terminal of the second transistor M2 is connected to the second photodiode PD2. The control terminal of the second transistor M2 is connected to the scintillation driving unit 400 to access the scintillation exposure signal TX2. The second terminal of the second transistor M2 is connected to the scintillation reading unit 500 to output a scintillation signal to the scintillation reading unit 500. Taking the second transistor M2 as an NMOS transistor as an example, when the scintillation exposure signal TX2 is at a high level, the second transistor M2 is turned on, and the scintillation detection circuit 12 is in the exposure state. The scintillation reading unit 500 receives the second photocurrent generated by the second photodiode PD2 and processes the second photocurrent, such as integrating the second photocurrent to generate an integrated voltage. When the scintillation exposure signal TX2 is at a low level, the second transistor M2 is turned off, and the scintillation detection circuit 12 is in the reading state. The scintillation reading unit 500 reads the signal (such as the integrated voltage) processed by the second photocurrent, and finally obtains scintillation data.

[0087] It can be understood that the transistors mentioned in the above embodiments are not limited to NMOS transistors. The transistors in the above embodiments can also be, but are not limited to, PMOS transistors, triodes, JEFT transistors, IGBT transistors, etc. with switching functions.

[0088] It should be noted that, in the embodiments of the present application, the first pole / first end of each transistor is one of the source and the drain (or the emitter and the collector), the second pole / second end of each transistor is the other of the source and the drain (or the emitter and the collector), and the control end of each transistor may refer to the gate / base, etc. Exemplarily, in the case where the transistor is a P-type transistor, the first pole / first end of the transistor is the source, and the second pole / second end is the drain; Exemplarily, in the case where the transistor is an N-type transistor, the first pole / first end of the transistor is the drain, and the second pole / second end is the source.

[0089] It should be noted that the above content about the first output sub-unit 112 and the second transmission sub-unit 121 is only an exemplary embodiment of the present application. Those skilled in the art can make equivalent modified designs for the first output sub-unit 112 and the second transmission sub-unit 121 under the guidance of the present application. For example, refer to Figure 4 , Figure 4 shows another schematic diagram of the pixel circuit 11 and the scintillation detection circuit 12 in the embodiments of the present application. The second transmission sub-unit 121 may further include a second reset transistor Ms2, a second amplification transistor Ma2, and a second output transistor Mo2. The second reset transistor Ms2 is controlled by the second reset signal RST2, the second output transistor Mo2 is controlled by the second scan signal SD2, the control end of the second amplification transistor Ma2 is connected to the second floating diffusion node FD2, and the second photocurrent of the second photodiode PD2 can change the voltage VPD2 of the second floating diffusion node FD2. Therefore, the scintillation signal is output through the second amplification transistor Ma2 and the second output transistor Mo2.

[0090] For another example, refer to Figure 5 , Figure 5 shows another schematic diagram of the pixel circuit 11 in the embodiments of the present application. Different from Figure 3 , Figure 3 being adapted to the rolling shutter exposure mode of the image sensor, in Figure 5 , the first transmission sub-unit 111 further includes a transistor M3 and a storage capacitor C0. The transistor M3 is controlled by the control signal TX3. When the first transistor M1 is turned on and the transistor M3 is turned off, it is convenient for the storage capacitor C0 to temporarily store the photocurrent charges, and when the first transistor M1 is turned off and the transistor M3 is turned on, the temporarily stored photocurrent charges are transferred to the first floating diffusion node FD1 and a first photosensitive signal VPD1 is generated to be adapted to the global exposure mode of the image sensor.

[0091] In some embodiments of the present application, refer to Figure 6 , Figure 6FIG. 0 shows a schematic diagram of a scintillation reading unit 500 and a scintillation detection circuit 12 in an embodiment of the present application. Among them, N pixel regions 10 include the scintillation detection circuit 12. The scintillation reading unit 500 includes at least one signal conversion subunit 501 and at least one reading subunit 502, and the signal conversion subunits 501 and the reading subunits 502 are in one-to-one correspondence; the signal conversion subunit 501 is configured to receive the second photo-generated current output by the scintillation detection circuits 12 of M pixel regions 10, and output a scintillation voltage signal Vfs based on the second photo-generated current output by the scintillation detection circuits 12 of M pixel regions 10; the reading subunit 502 is configured to read the scintillation voltage signal Vfs to obtain scintillation data; wherein, M is less than or equal to N, and M is an integer greater than 1.

[0092] It should be noted that, in order to ensure the size of the first photodiode PD1, the size of the second photodiode PD2 is usually small. Therefore, the second photo-generated current generated by the second photodiode PD2 of a single scintillation detection circuit 12 is usually small, which will result in a low signal-to-noise ratio of the scintillation signal input to the scintillation reading unit 500, and further lead to a problem of decreased measurement accuracy of the scintillation frequency of the scintillation light source. In the above embodiment, since the signal conversion subunit 501 receives the second photo-generated currents IPD2[1], IPD2[2]... IPD2[m] output by the scintillation detection circuits 12 of M pixel regions 10, that is to say, the scintillation signal input to the scintillation reading unit 500 is the second photo-generated currents IPD2[1], IPD2[2]... IPD2[n] output by the scintillation detection circuits 12 of M pixel regions 10. Therefore, the signal-to-noise ratio of the scintillation signal input to the scintillation reading unit 500 can be improved. After the reading subunit 502 reads the scintillation voltage signal Vfs output by the signal conversion subunit 501, scintillation data can be obtained. Finally, while ensuring the area of the pixel circuit 11 to improve the signal-to-noise ratio of the image signal, the measurement error of the scintillation data can also be reduced.

[0093] In some embodiments of the present application, N pixel regions 10 including the scintillation detection circuit 12 are arranged around the center of the pixel array 100. For example, referring to Figure 7 , Figure 7 FIG. 10 shows a schematic diagram of a pixel array 100 in an embodiment of the present application. Among them, the center of the pixel array 100 is point O, and four pixel regions 10 including the scintillation detection circuit 12 are respectively arranged at the four diagonals of the center O of the pixel array 100. In this way, N pixel regions 10 including the scintillation detection circuit 12 are arranged in an array that is scaled proportionally with respect to the pixel array 100. This can reduce the number of pixel regions 10 including the scintillation detection circuit 12 while facilitating ensuring that the fields of view of the N scintillation detection circuits 12 are consistent with the field of view of the pixel array 100.

[0094] Understandably, the arrangement of the N pixel regions 10 including the scintillation detection circuit 12 is not limited to this. For example, referring to Figure 8 , Figure 8 shows another schematic diagram of the pixel array 100 in an embodiment of the present application. The N pixel regions 10 including the scintillation detection circuit 12 can also be arranged in the same column; again, for example, referring to Figure 9 , Figure 9 shows another schematic diagram of the pixel array 100 in an embodiment of the present application. The N pixel regions 10 including the scintillation detection circuit 12 can also be arranged in the same row.

[0095] In some embodiments of the present application, referring to Figure 10 , Figure 10 shows another schematic diagram of the scintillation reading unit 500 and the scintillation detection circuit 12 in an embodiment of the present application. The signal conversion sub-unit 501 includes an operational amplifier OP, a reset switch SI, and an integration capacitor CI; the first input terminal of the operational amplifier OP is connected to a preset reference voltage Vref, the second input terminal of the operational amplifier OP is connected to each scintillation detection circuit 12 to access the second photocurrent, and the output terminal of the operational amplifier OP is connected to the reading sub-unit 502 to output a scintillation voltage signal Vfs to the reading sub-unit 502; the first end of the integration capacitor CI is connected to the second input terminal of the operational amplifier OP, and the second end of the integration capacitor CI is connected to the output terminal of the operational amplifier OP; the first end of the reset switch SI is connected to the second input terminal of the operational amplifier OP, and the second end of the reset switch SI is connected to the output terminal of the operational amplifier OP.

[0096] It should be noted that the operational amplifier OP and the integration capacitor CI form a current integrator. When the reset switch SI is closed, the plate charge of the integration capacitor CI connected to the second input terminal of the operational amplifier OP is reset; when the reset switch SI is opened and the first transistor M1 of the scintillation detection circuit 12 in the N pixel regions 10 is turned on, the integration capacitor CI integrates the second photocurrent of the second photodiodes PD2 in the N pixel regions 10, and the scintillation voltage signal Vfs at the output terminal of the operational amplifier OP gradually increases; when the reset switch SI is opened and the first transistor M1 of the scintillation detection circuit 12 in the N pixel regions 10 is turned off, the second photodiodes PD2 in the N pixel regions 10 no longer consume the charge of the integration capacitor CI, and the scintillation voltage signal Vfs at the output terminal of the operational amplifier OP is stable. Therefore, the reading sub-unit 502 can read the scintillation voltage signal Vfs output by the operational amplifier OP at this time, so as to obtain the scintillation data. <s

[0097] It should be noted that the above content about the image sensor is intended to clearly illustrate the implementation verification process of the present application. Those skilled in the art can make equivalent modified designs under the guidance of the present application. For example, referring to Figure 11, Figure 11 FIG. Figure 11 shows another schematic diagram of the flash reading unit 500 and the flash detection circuit 12 in the embodiments of the present application. A second transistor M2 for controlling the exposure of all the second photodiodes PD2 can also be arranged outside the pixel array 100 (such as inside the flash reading unit 500).

[0098] Further, in order to better implement the image sensor in the embodiments of the present application, based on the image sensor, the present application further provides an electronic device, and the electronic device includes the image sensor in any of the above embodiments. Since the electronic device in the embodiments of the present application is provided with the image sensor in the above embodiments, it has all the beneficial effects of the above image sensor, which will not be elaborated herein again.

[0099] In the above embodiments, the descriptions of the respective embodiments have their own emphases. For the parts not detailed in a certain embodiment, reference can be made to the detailed descriptions of other embodiments above, which will not be elaborated herein again.

[0100] The basic concepts have been described above. Obviously, for those skilled in the art, the above detailed disclosure is only an example and does not constitute a limitation to the present application. Although not explicitly stated herein, those skilled in the art may make various modifications, improvements, and corrections to the present application. Such modifications, improvements, and corrections are proposed in the present application, so such modifications, improvements, and corrections still belong to the spirit and scope of the exemplary embodiments of the present application.

[0101] Meanwhile, the present application uses specific terms to describe the embodiments of the present application. Such as "one embodiment", "an embodiment", and / or "some embodiments" mean a certain feature, structure, or characteristic related to at least one embodiment of the present application. Therefore, it should be emphasized and noted that the "one embodiment" or "an embodiment" or "an alternative embodiment" mentioned twice or more at different positions in this specification is not necessarily the same embodiment. In addition, certain features, structures, or characteristics in one or more embodiments of the present application can be combined appropriately.

[0102] The above provides a detailed introduction to an image sensor and an electronic device provided in the embodiments of the present application. Specific examples are used herein to elaborate on the principles and implementation manners of the present invention. The descriptions of the above embodiments are only used to help understand the method and its core idea of the present invention; at the same time, for those skilled in the art, there will be changes in the specific implementation manners and application scopes according to the idea of the present invention. In summary, the content of this specification should not be construed as a limitation to the present invention.

Claims

1. An image sensor, characterized in that, Comprising: A pixel array, the pixel array including a plurality of pixel regions arranged in an array, each pixel region including a pixel circuit, and at least one of the pixel regions including a scintillation detection circuit; An exposure control module, the exposure control module being electrically connected to the scintillation detection circuit, for determining the scintillation frequency of a scintillation light source according to a scintillation signal output by the scintillation detection circuit, and controlling the exposure duration of the pixel circuit according to the scintillation frequency.

2. The image sensor according to claim 1, characterized in that, The pixel circuit includes a first photodiode for generating a first photocurrent, and the scintillation detection circuit includes a second photodiode for generating a second photocurrent; Wherein, the pixel circuit outputs an image signal according to the first photocurrent output by the first photodiode, and the second photocurrent output by the second photodiode is used as the scintillation signal.

3. The image sensor according to claim 2, characterized in that, The size of the second photodiode is smaller than the size of the first photodiode.

4. The image sensor according to claim 2, wherein, The exposure control module includes a scintillation driving unit, a scintillation reading unit, and a processing unit; The scintillation driving unit is connected to each scintillation detection circuit, for controlling the exposure of the scintillation detection circuit and outputting a scintillation signal; The scintillation reading unit is connected to the scintillation detection circuit, for reading the scintillation signal output by the scintillation detection circuit to obtain scintillation data; The processing unit is used for determining the scintillation frequency of the scintillation light source according to the scintillation data, and controlling the exposure duration of the pixel circuit according to the scintillation frequency.

5. The image sensor according to claim 4, wherein N of the pixel regions include scintillation detection circuits, the scintillation reading unit includes at least one signal conversion sub-unit and at least one reading sub-unit, and the signal conversion sub-units and the reading sub-units are in one-to-one correspondence; The signal conversion sub-unit is used for receiving the second photocurrents output by the scintillation detection circuits of M of the pixel regions, and outputting a scintillation voltage signal based on the second photocurrents output by the scintillation detection circuits of M of the pixel regions; The reading sub-unit is used for reading the scintillation voltage signal to obtain scintillation data; Wherein, M is less than or equal to N, and M is an integer greater than 1.

6. The image sensor according to claim 5, wherein The signal conversion sub-unit includes an operational amplifier, a reset switch, and an integrating capacitor; A first input terminal of the operational amplifier is connected to a preset reference voltage, and a second input terminal of the operational amplifier is connected to each scintillation detection circuit to access the second photocurrent; A first end of the integrating capacitor is connected to the second input terminal of the operational amplifier, and a second end of the integrating capacitor is connected to an output terminal of the operational amplifier; A first end of the reset switch is connected to the second input terminal of the operational amplifier, and a second end of the reset switch is connected to the output terminal of the operational amplifier; Wherein, the output terminal of the operational amplifier is connected to the reading sub-unit to output a scintillation voltage signal to the reading sub-unit.

7. The image sensor according to claim 6, wherein, The reading sub-unit includes an analog-to-digital converter, and an input terminal of the analog-to-digital converter is connected to the output terminal of the operational amplifier.

8. The image sensor according to claim 5, wherein The N pixel regions including the scintillation detection circuits are arranged around the center of the pixel array; or The N pixel regions including the scintillation detection circuits are arranged in the same column; or The N pixel regions each including the scintillation detection circuit are arranged in the same row.

9. The image sensor according to claim 2, wherein The pixel circuit further includes a first transfer sub-unit and a first output sub-unit; The first transfer sub-unit is configured to control the conduction and cutoff between the first photodiode and the first floating diffusion node, so that the first floating diffusion node generates a first photosensitive signal related to the light intensity based on the first photo-generated current; The first output sub-unit is configured to output the image signal according to the first photosensitive signal of the first floating diffusion node.

10. The image sensor according to claim 9, wherein, The first transfer sub-unit includes a first transistor, and the first output sub-unit includes a first reset transistor, a first amplifying transistor, and a first output transistor; A first end of the first transistor is connected to the first photodiode, a second end of the first transistor is connected to the first floating diffusion node, and a control end of the first transistor receives an image exposure signal; A first end of the first reset transistor is connected to a power supply terminal, a second end of the first reset transistor is connected to the first floating diffusion node, and a control end of the first reset transistor is configured to receive a first reset signal; A first end of the first amplifying transistor is connected to the power supply terminal, a control end of the first amplifying transistor is connected to the first floating diffusion node, and a second end of the first amplifying transistor is connected to a first end of the first output transistor; A control end of the first output transistor receives a first scan signal, and a second end of the first output transistor outputs the image signal.

11. The image sensor according to claim 2, wherein The scintillation detection circuit further includes a second transfer sub-unit; The second transfer sub-unit is configured to control the second photodiode to output the second photo-generated current.

12. The image sensor according to claim 11, wherein, The second transfer sub-unit includes a second transistor; A first end of the second transistor is connected to the second photodiode, a control end of the second transistor receives a scintillation exposure signal, and a second end of the second transistor outputs the scintillation signal.

13. An electronic device, characterized in that, An image sensor comprising the image sensor according to any one of claims 1 to 12.

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