WO2022089346A1

WO2022089346A1 - Sensor

Info

Publication number: WO2022089346A1
Application number: PCT/CN2021/126015
Authority: WO
Inventors: 李沛德; 官龙腾
Original assignee: 维沃移动通信有限公司
Priority date: 2020-10-29
Filing date: 2021-10-25
Publication date: 2022-05-05
Also published as: CN112312097A; CN112312097B

Abstract

The present application relates to the technical field of image processing. Disclosed is a sensor, for solving the technical problem in the prior art that multiple exposures would cause the problems of image edge dislocation, image distortion and the like, thus affecting an image display effect. The sensor comprises a color filter array and a pixel circuit; the pixel circuit comprises a photoelectric conversion module; the photoelectric conversion module comprises a first photoelectric conversion element and a second photoelectric conversion element. The color filter array comprises a plurality of color filter units, and each color filter unit comprises a first light-transmitting element; the position of the first light-transmitting element corresponds to the position of the first photoelectric conversion element or the position of the second photoelectric conversion element. The first light-transmitting element is a red light-transmitting element, a green light-transmitting element, or a blue light-transmitting element.

Description

sensor

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the priority of the Chinese patent application filed with the Chinese Patent Office on October 29, 2020, the application number is 202011178963.2, and the invention name is "a sensor", the entire content of which is incorporated into this application by reference.

technical field

The present application belongs to the technical field of image processing, and specifically relates to a sensor.

Background technique

At present, more and more users choose to use terminals such as mobile phones to take pictures.

In order to obtain an ideal photo image, in the prior art, multiple exposures are often performed when taking pictures to obtain multiple images with different exposure degrees, and then image fusion is performed on the obtained multiple images with different exposure degrees to obtain the final image. photo.

In the process of realizing the present application, the applicant found that there are at least the following problems in the prior art: multiple exposures will cause problems such as image edge dislocation and image distortion, thereby affecting the image display effect.

SUMMARY OF THE INVENTION

The purpose of the present application is to provide a sensor that at least solves the problems that multiple exposures will cause image edge dislocation, image distortion, etc., and then affect the image display effect.

In order to solve the above technical problems, this application is implemented as follows:

An embodiment of the present application proposes a sensor, including: a color filter array and a pixel circuit, the pixel circuit includes a photoelectric conversion module, the photoelectric conversion module includes a first photoelectric conversion element and a second photoelectric conversion element, the color filter The filter array includes a plurality of color filter units, the color filter units include a first light-transmitting element, and the position of the first light-transmitting element corresponds to the position of the first photoelectric conversion element or the first light-transmitting element. The positions of the two photoelectric conversion elements correspond to each other, and the first light transmitting element is a red light transmitting element, a green light transmitting element or a blue light transmitting element.

In the embodiments of the present application, by adding one photoelectric conversion element in the sensor, multiple exposure images can be obtained based on two photoelectric conversion elements in the sensor in one exposure. In this way, when the multiple exposure images are fused , which can effectively reduce the problems of image edge dislocation and image distortion caused by multiple exposures, thereby improving the display effect of the image.

Description of drawings

The above and/or additional aspects and advantages of the present application will become apparent and readily understood from the following description of embodiments in conjunction with the accompanying drawings, wherein:

FIG. 1 is a schematic diagram of a pixel circuit provided by an embodiment of the present application;

FIG. 2 is a schematic diagram of an arrangement of a first photoelectric conversion element and a second photoelectric conversion element provided by an embodiment of the present application;

FIG. 3 is a schematic diagram of another pixel circuit provided by an embodiment of the present application;

FIG. 4 is a schematic diagram of another pixel circuit provided by an embodiment of the present application;

FIG. 5 is a schematic diagram of another pixel circuit provided by an embodiment of the present application;

6 is a schematic diagram of a sensor provided by the present application;

7 is a schematic diagram of a color filter array provided by the present application;

FIG. 8 is a schematic structural diagram of a camera module provided by the present application.

Reference number:

10—pixel circuit; 101—photoelectric conversion module; 102—capacitor module; 103—reset switch; 1011—first photoelectric conversion element; 1012—second photoelectric conversion element; 1021—first capacitor; 1022—second capacitor; 1023 - third capacitor; 1013 - first photoelectric conversion control switch; 1014 - second photoelectric conversion control switch; 104 - output module; 1041 - source follower; 1042 - column selection signal switch; 1024 - first capacitor control switch; 1025 20—color filter unit; 30—color filter array; 201—first light-transmitting element; 202—second light-transmitting element; 40—camera module; 401—protective film; 402— Lens; 403—voice coil motor; 404—supporting part; 405—infrared filter; 406—sensor; 407—soft board; 408—connecting part.

Detailed ways

The following will describe in detail the embodiments of the present application, examples of which are illustrated in the accompanying drawings, wherein the same or similar reference numerals refer to the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present application, but should not be construed as a limitation on the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the protection scope of the present application.

The features of the terms "first" and "second" in the description and claims of this application may expressly or implicitly include one or more of such features. In the description of this application, unless stated otherwise, "plurality" means two or more. In addition, "and/or" in the description and claims indicates at least one of the connected objects, and the character "/" generally indicates that the associated objects are in an "or" relationship.

In the description of this application, it is to be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", " Rear, Left, Right, Vertical, Horizontal, Top, Bottom, Inner, Outer, Clockwise, Counterclockwise, Axial, The orientations or positional relationships indicated by "radial direction", "circumferential direction", etc. are based on the orientations or positional relationships shown in the accompanying drawings, which are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying the indicated devices or elements. It must have a specific orientation, be constructed and operate in a specific orientation, and therefore should not be construed as a limitation of the present application.

In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installed", "connected" and "connected" should be understood in a broad sense, for example, it may be a fixed connection or a detachable connection Connection, or integral connection; can be mechanical connection, can also be electrical connection; can be directly connected, can also be indirectly connected through an intermediate medium, can be internal communication between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood in specific situations.

An embodiment of the present application provides a pixel circuit 10, as shown in FIG. 1, including: a photoelectric conversion module 101, a capacitor module 102, and a reset switch 103, the first end of the photoelectric conversion module 101 is grounded, and the second end of the photoelectric conversion module 101 Connect the first end of the reset switch 103; the capacitor module 102 includes a first capacitor 1021, the first end of the first capacitor 1021 is grounded, and the second end of the first capacitor 1021 is connected to the first end of the reset switch 103; wherein, the photoelectric The conversion module 101 includes a first photoelectric conversion element 1011 and a second photoelectric conversion element 1012 connected in parallel; the first end of the first photoelectric conversion element 1011 is grounded, and the second end of the first photoelectric conversion element 1011 is connected to the reset switch 103 The first end; the first end of the second photoelectric conversion element 1012 is grounded, and the second end of the second photoelectric conversion element 1012 is connected to the first end of the reset switch 103 .

The first photoelectric conversion element 1011 and the second photoelectric conversion element 1012 are devices that convert optical signals into electrical signals, for example, the first photoelectric conversion element 1011 and the second photoelectric conversion element 1012 may be photodiodes. The arrangement of the first photoelectric conversion elements 1011 and the second photoelectric conversion elements 1012 may also be various, for example, the second photoelectric conversion elements 1012 are arranged between adjacent first photoelectric conversion elements 1011; 1011 may be annular, and the second photoelectric conversion element 1012 is embedded in the first photoelectric conversion element 1011, as shown in FIG. 2 . It can be understood that the arrangement of the first photoelectric conversion element 1011 and the second photoelectric conversion element 1012 is not limited, and can be adjusted according to the layout and space of the terminal.

In order to control the first photoelectric conversion element 1011 and the second photoelectric conversion element 1012 to read the voltage corresponding to the first photoelectric conversion element 1011 and the second photoelectric conversion element 1012 after being photosensitive, in one embodiment, the present application provides The photoelectric conversion module 101 in the pixel circuit further includes at least one of the first photoelectric conversion control switch 1013 and the second photoelectric conversion control switch 1014; in the case where the photoelectric conversion module 101 includes the first photoelectric conversion control switch 1013, the first photoelectric conversion control switch 1013 The first end of a photoelectric conversion control switch 1013 is connected to the second end of the first photoelectric conversion element 1011, and the second end of the first photoelectric conversion control switch 1013 is connected to the first end of the reset switch 103; the photoelectric conversion module 101 includes a second end In the case of the photoelectric conversion control switch 1014, the first end of the second photoelectric conversion control switch 1014 is connected to the second end of the second photoelectric conversion element 1012, and the second end of the second photoelectric conversion control switch 1014 is connected to the first end of the reset switch 103. end. Preferably, in order to control the first photoelectric conversion element 1011 and the second photoelectric conversion element 1012 respectively, so as to read the voltages corresponding to the first photoelectric conversion element 1011 and the second photoelectric conversion element 1012 after being photosensitive, the photoelectric conversion module 101 includes a first photoelectric conversion element 1011 and a second photoelectric conversion element 1012. A photoelectric conversion control switch 1013 and a second photoelectric conversion control switch 1014, as shown in FIG. 3; the first end of the first photoelectric conversion control switch 1013 is connected to the second end of the first photoelectric conversion element 1011, and the first photoelectric conversion control switch The second end of 1013 is connected to the first end of the reset switch 103; the first end of the second photoelectric conversion control switch 1014 is connected to the second end of the second photoelectric conversion element 1012, and the second end of the second photoelectric conversion control switch 1014 is connected to the reset The first end of switch 103 .

Wherein, the first photoelectric conversion control switch 1013 and the second photoelectric conversion control switch 1014 may be MOSFETs (Metal-Oxide-Semiconductor Field-Effect Transistor, Metal-Oxide Semiconductor Field-Effect Transistor). One end is the source, the second end is the drain, the gate of the MOSFET is connected to a timing control module (not shown in the figure), and the timing control module is used to control the closing and opening of each switch in the pixel circuit Order.

Further, in order to output the corresponding voltages after the first photoelectric conversion element 1011 and the second photoelectric conversion element 1012 are photosensitive, the pixel circuit provided by the present application may further include an output module 104, as shown in FIG. 3, the first end of the output module 104 is grounded , the second end of the output module 104 is connected to the first end of the reset switch 103 . The output module 104 may further include a source follower 1041 and a column selection signal switch 1042. The first end of the source follower 1041 is connected to the first end of the reset switch 103, and the second end of the source follower 1041 is connected to the column selector The first terminal of the signal switch 1042 and the second terminal of the column selection signal switch 1042 are grounded.

The working principle of the pixel circuit provided by the present application is as follows: the photoelectric conversion element generates electrons inside to form charges under illumination, transfers the charges to the capacitor to charge the capacitor to form a voltage, and reads the voltage of the capacitor, that is, after the photoelectric conversion element is exposed to light Corresponding voltage, based on this voltage, the corresponding exposure image after the photoelectric conversion element is exposed to light can be obtained. The exposure degree of the exposure image has a corresponding relationship with the magnitude of the voltage. Generally speaking, the greater the voltage, the greater the exposure degree of the obtained exposure image phenomenon, that is, the greater the light intensity collected by the photoelectric conversion element.

Based on the above working principle, the workflow of the pixel circuit provided by this application is as follows:

First, read the voltage corresponding to the first photoelectric conversion element 1011 after receiving light. When the first photoelectric conversion control switch 1013 is closed, the charge generated by the first photoelectric conversion element 1011 is transferred to the first capacitor 1021, the source follower 1041 records the voltage U1 of the first capacitor 1021, the column selection signal switch 1042 is closed, and the Vout circuit output voltage value. Further, based on this voltage, an exposure image corresponding to the first photoelectric conversion element 1011 after being exposed to light is obtained.

Then, the voltage corresponding to the second photoelectric conversion element 1012 after being light-sensitive is read. When the second photoelectric conversion control switch 1014 is closed, the charge generated by the second photoelectric conversion element 1012 is transferred to the first capacitor 1021, the source follower 1041 records the voltage U2 of the first capacitor 1021, the column selection signal switch 1042 is closed, and the Vout circuit output voltage value. Further, based on this voltage, an exposure image corresponding to the second photoelectric conversion element 1012 after being exposed to light is obtained.

Among them, it can be understood that the voltage corresponding to the first photoelectric conversion element 1011 after being exposed to light is read first, and then the voltage corresponding to the second photoelectric conversion element 1012 after being exposed to light is read, which is only an example, and does not constitute a limitation to this application. It is also possible to first read the voltage corresponding to the second photoelectric conversion element 1012 after being photosensitive, and then read the voltage corresponding to the first photoelectric conversion element 1011 after being photosensitive.

It can be seen that, based on the pixel circuit provided in this application, since the process of charge transfer and voltage reading is instantaneous, it takes almost no time. The exposure images corresponding to the photoelectric conversion element after being exposed to light can be regarded as being obtained simultaneously, that is, two exposure images can be obtained at the same time through one exposure. In the related art, two exposure images are obtained by controlling the photoelectric conversion element to be sensitized twice in succession; then the difference between the exposure image corresponding to the first exposure of the photoelectric conversion element and the exposure image corresponding to the second exposure of the photoelectric conversion element is obtained. It is at least the time duration that the photoelectric conversion element lasts for the second time photosensitive. That is to say, there is a time interval between the acquisition of the two exposure images. Due to the existence of the time interval, if the shooting scene changes within this interval, for example, there are fast-moving objects in the shooting scene, the two exposure images will be During fusion, the two images are difficult to align, and the moving objects appear smearing and other image distortions. However, based on the pixel circuit provided by the embodiment of the present application, two exposure images can be acquired at the same time, that is, there is no time interval between the acquisition of the two exposure images, and the shooting scene at the same moment will not change, and then the two exposure images are fused. It can effectively reduce the image distortion such as difficult alignment and smearing of moving objects, greatly improve the quality of the image, and further improve the display effect of the image.

Since the photoelectric conversion elements in the pixel circuit may be often exposed to light conditions, for example, the lens cover in the camera module of a mobile phone is not provided with a lens cover, so that the photoelectric conversion elements in the pixel circuit in the image sensor are always exposed to light conditions, then the internal Charges will be generated. In order to make the corresponding voltage of the photoelectric conversion element after exposure to the photoelectric conversion element can truly reflect the amount of charge generated by the photoelectric conversion element for this exposure, it is necessary to clear the residual charge inside the photoelectric conversion element before taking the image. It can be understood that if the residual charge is not emptied, and the residual charge is transferred to the capacitor together with the charge generated by the photoelectric conversion element during this shooting, the resulting voltage will be too large, and the resulting image will be similar to the actual shooting scene. image is biased. For example, the photoelectric conversion element sensitizes a certain sampling point in the shooting scene. If the residual charge is not emptied, the residual charge is transferred to the capacitor together with the electric charge generated by the photoelectric conversion element during this shooting. The position of the sampling point is more exposed than the position of the sampling point in the actual shooting scene, that is, the brightness is higher, and the picture is distorted. Therefore, in an embodiment, in the pixel circuit 10 provided by the present application, the second end of the reset switch 103 is connected to the first power supply voltage VDD1, as shown in FIG. 3, so that the first power supply voltage VDD1 is loaded at the first power supply voltage VDD1. The photoelectric conversion element 1011 and the second photoelectric conversion element 1012 are used to clear the residual charges in the first photoelectric conversion element 1011 and the second photoelectric conversion element 1012 . The specific process is: closing the reset switch 103, the first photoelectric conversion control switch 1013 and the second photoelectric conversion control switch 1014, then the first power supply voltage VDD1 is loaded on the first photoelectric conversion element 1011 and the second photoelectric conversion element 1012, and the Charges remaining in the first photoelectric conversion element 1011 and the second photoelectric conversion element 1012 . Then, the reset switch 103, the first photoelectric conversion control switch 1013 and the second photoelectric conversion control switch 1014 are turned off, so that the first photoelectric conversion element 1011 and the second photoelectric conversion element 1012 start to receive light simultaneously to generate electric charges.

In addition, in the process of capturing images before this shooting, the first capacitor 1021 may have residual charge, which is similar to the above-mentioned reason not to allow the residual charge of the photoelectric conversion element to distort the captured image. After clearing the first capacitor 1021 After the electrons remaining in the photoelectric conversion element 1011 and the second photoelectric conversion element 1012 , the electric charge remaining in the first capacitor 1021 also needs to be emptied. The specific process is: keep the first photoelectric conversion control switch 1013 and the second photoelectric conversion control switch 1014 disconnected, close the reset switch 103, load the power supply voltage VDD1 on the first capacitor 1021, and clear the residual charge on the first capacitor 1021. After the charge remaining on the first capacitor 1021 is emptied, the above process of reading the voltage corresponding to the first photoelectric conversion element 1011 and reading the voltage corresponding to the second photoelectric conversion element 1012 is performed.

In practical applications, according to different requirements, the first photoelectric conversion element 1011 and the second photoelectric conversion element 1012 may have the same size or different sizes, and the size may be the size of the photosensitive area of the photoelectric conversion element.

In one embodiment, the first photoelectric conversion element 1011 and the second photoelectric conversion element 1012 have the same size. When the size of the first photoelectric conversion element 1011 and the second photoelectric conversion element 1012 are the same, the number of electrons generated by the two in the same time is the same, and the formed charges are the same, which are then transferred to the electrons read on the first capacitor 1021. The voltage is also the same. The magnitude of the voltage value is related to the exposure degree of the image. In this embodiment, two images with the same exposure degree can be obtained, and multiple frames of noise reduction can be performed based on the two images. In addition, since these two images with the same exposure are obtained at the same time, when performing multi-frame noise reduction based on these two images, it can effectively reduce the problem of image distortion such as edge dislocation and smear, and greatly improve the multi-frame noise reduction. The quality of the resulting image after noise reduction.

In another embodiment, the sizes of the first photoelectric conversion element 1011 and the second photoelectric conversion element 1012 are different. When the size of the first photoelectric conversion element 1011 and the second photoelectric conversion element 1012 are different, the number of electrons generated by the two in the same time is different, and the formed charges are also different, and then transferred to the first capacitor 1021 for reading The voltages obtained are also different. The magnitude of the voltage value is related to the exposure degree of the image. In this embodiment, two images with different exposure degrees can be obtained, and HDR fusion can be performed based on the two images. In addition, since these two images with different exposure levels are obtained at the same time, when HDR fusion is performed based on these two images, the problems of image distortion such as edge dislocation and smear can be effectively reduced, which greatly improves the results obtained after HDR fusion. image quality.

The size ratio of the first photoelectric conversion element 1011 and the second photoelectric conversion element 1012 corresponds to the exposure degree ratio of two images with different exposure degrees. The larger the size of the photoelectric conversion element, the more charges are generated per unit time under light conditions, the greater the voltage corresponding to the photoelectric conversion element after exposure, and the higher the exposure degree of the exposure image corresponding to the photoelectric conversion element after exposure. For example, the size ratio of the first photoelectric conversion element 1011 and the second photoelectric conversion element 1012 is 8:1, and the capacitance of the first capacitor 1021 is 1. According to the formula Q=C*V, it can be known that the voltage is proportional to Q. The size ratio of the photoelectric conversion element 1011 and the second photoelectric conversion element 1012 is 8:1, and the ratio of the charge generated by the first photoelectric conversion element 1011 to the charge generated by the second photoelectric conversion element 1012 is 8:1 in the same photosensitive time period, Furthermore, it can be obtained that the ratio of the voltage corresponding to the first photoelectric conversion element 1011 to the voltage corresponding to the second photoelectric conversion element 1012 after being photosensitive is 8:1, that is, the exposure degree of the exposure image corresponding to the first photoelectric conversion element 1011 after being photosensitive is equal to The ratio of the exposure degree of the exposure image corresponding to the second photoelectric conversion element 1012 after exposure is 8:1.

It can be seen that the pixel circuit provided by the present application can obtain two exposure images by setting two photoelectric conversion elements and one capacitor. Based on this principle, the number of photoelectric conversion elements and/or the number of capacitors can also be increased, so that more exposure images can be obtained simultaneously with one exposure. For example, three photoelectric conversion elements and one capacitor are set to obtain three exposure images; further, the size of the three photoelectric conversion elements can be limited to adapt to multi-frame noise reduction and HDR respectively.

In an embodiment, the capacitor module 102 in the pixel circuit 10 provided by the present application further includes a second capacitor 1022 connected in parallel with the first capacitor 1021 , as shown in FIG. 4 ; The terminal is grounded, and the second terminal of the second capacitor 1022 is connected to the first terminal of the reset switch 103 . The capacitor module 102 further includes a first capacitor control switch 1024 connected in parallel with the first capacitor 1021, the first end of the first capacitor control switch 1024 is connected to the second end of the second capacitor 1022, the The second terminal of the first capacitance control switch 1024 is connected to the first terminal of the reset switch 103 . The first capacitance control switch 1024 may be a MOSFET, and the gate of the MOSFET is connected to a timing control module, and the timing control module is used to control the sequence of closing and opening of each switch in the pixel circuit.

In the embodiment of the present application, more exposure images can be obtained by adding the second capacitor 1022 in parallel with the first capacitor 1021 to control the working state of the first capacitor control switch 1024 . The specific process is as follows: First, read the voltage corresponding to the first photoelectric conversion element 1011 after being light-sensitive. Close the first photoelectric conversion control switch 1013, open the first capacitor control switch 1024, read the voltage on the first capacitor 1021, and obtain the first exposure image corresponding to the first photoelectric conversion element 1011 after being photosensitive; then close the first capacitor The switch 1024 is controlled to read the voltages on the first capacitor 1021 and the second capacitor 1022 connected in parallel, so as to obtain the second exposure image corresponding to the first photoelectric conversion element 1011 after being exposed to light. Then, read the voltage corresponding to the second photoelectric conversion unit 1012 after receiving the light. Close the second photoelectric conversion control switch 1014 (the first photoelectric conversion control switch 1013 is in the off state at this time), open the first capacitor control switch 1024, read the voltage on the first capacitor 1021, and obtain the second photoelectric conversion element 1012 The first exposure image corresponding to the photosensitive image; then close the first capacitor control switch 1024, read the voltage on the parallel first capacitor 1021 and the second capacitor 1022, and obtain the second photoelectric conversion element 1012 corresponding to the photosensitive image. Expose the image. It can be seen that by increasing the number of capacitors connected in parallel with the first capacitor 1021, more exposure images can be obtained.

In an embodiment, the capacitor module 102 in the pixel circuit 10 provided by the present application further includes a third capacitor 1023 connected in parallel with the first capacitor 1021 and the second capacitor 1022, as shown in FIG. 5; The first end of the capacitor 1023 is grounded, and the second end of the third capacitor 1023 is connected to the first end of the reset switch 103 . The capacitor module 102 further includes a second capacitor control switch 1025 connected in parallel with the first capacitor 1021 and the second capacitor 1022 respectively, and the first end of the second capacitor control switch 1025 is connected to the first capacitor 1025. The second terminal of the three capacitors 1023 and the second terminal of the second capacitor control switch 1025 are connected to the first terminal of the reset switch 103 . The second capacitance control switch 1025 may be a MOSFET, and the gate of the MOSFET is connected to a timing control module, and the timing control module is used to control the sequence of closing and opening of each switch in the pixel circuit.

When reading the voltage corresponding to the first photoelectric conversion element 1011 after being photosensitive, the exposure degree ratio can be obtained by controlling the closing and opening of the first capacitance control switch 1024 and the second capacitance control switch 1025 to read different voltage values. different images. For example, the capacitance ratio of the first capacitor 1021, the second capacitor 1022, and the third capacitor 1023 is a:b:c, and the charge generated after reading the first photoelectric conversion element 1011 (assuming that the first photoelectric conversion element 1011 is exposed to light is X ), first turn off both the first capacitor control switch 1024 and the second capacitor control switch 1025, then according to the formula Q=CV, the voltage on the first capacitor 1021 can be read as X/a; then close the first capacitor 1021 A capacitor control switch 1024, at this time, the first capacitor 1021 and the second capacitor 1022 are connected in parallel, and the parallel capacitor is a+b, then the voltage across the first capacitor 1021 and the second capacitor 1022 in parallel is X/(a+b) Then open the first capacitor control switch 1024, close the second capacitor control switch 1025, at this time the first capacitor 1021 and the third capacitor 1023 are connected in parallel, and the parallel capacitor is a+c, then the first capacitor 1021 and the third capacitor are read. The voltage across the capacitor 1023 in parallel is X/(a+c); then both the first capacitor control switch 1024 and the second capacitor control switch 1025 are closed, at this time the first capacitor 1021, the second capacitor 1022 and the third capacitor 1023 are connected in parallel, The parallel capacitance is a+b+c, then the voltage of the first capacitor 1021, the second capacitor 1022 and the third capacitor 1023 in parallel is read as X/(a+b+c), and the exposure degree ratio is obtained as (X/ a): [X/(a+b)]: [X/(a+c)]: Four exposure images of [X/(a+b+c)]. Then read the voltage corresponding to the second photoelectric conversion element 1012 after being exposed by the same steps. Assuming that the charge generated by the second photoelectric conversion element 1012 after being exposed is Y, the exposure degree ratio can be obtained as (Y/a): [Y/ (a+b)]: [Y/(a+c)]: Four exposure images of [Y/(a+b+c)]. Since the amount of charge generated by the photoelectric conversion unit is proportional to the size, 8 images with different exposure degrees can be obtained by setting the sizes of the first photoelectric conversion element 1011 and the second photoelectric conversion element 1012 to be different. For example, if the size of the first photoelectric conversion element 1011 is larger than the size of the second photoelectric conversion element 1012 , four images with strong exposure can be obtained based on the first photoelectric conversion element 1011 , and the exposure degree can be obtained based on the second photoelectric conversion element 1012 The weaker four images. Then, eight images with different exposure levels from underexposure to overexposure can be finally obtained, which makes the final fused HDR image of higher quality. Preferably, there is a multiple relationship between the size of the first photoelectric conversion element 1011 and the size of the second photoelectric conversion element 1012, so that the exposure ratios involved in the multiple exposure images obtained in this way are wider, and the bright and dark areas in the final fused HDR image The details will be clearer.

For example, the size ratio of the first photoelectric conversion element 1011 and the second photoelectric conversion element 1012 is 8:1, and the capacitance ratio of the first capacitor 1021 , the second capacitor 1022 and the third capacitor 1023 is 1:3:4. According to the above process, 8 exposure images with an exposure degree ratio of 320:80:64:40:40:10:8:5 can be obtained. It can be seen that the 8 exposure images involve a wider range of exposure ratios, which can make the details of the bright and dark areas in the final fused HDR image clearer. When performing fusion, you can directly HDR fusion of eight images, or you can first use the images with the same exposure ratio to perform multi-frame noise reduction, such as two images with the same exposure level of 40, and then reduce the multi-frame The image obtained from the noise is fused with the remaining exposed images by HDR. Since multi-frame noise reduction is performed first and then HDR fusion is performed, a photo with a high signal-to-noise ratio and high dynamic range can be finally obtained.

In practical applications, only a grayscale image with details can be obtained based on the pixel circuit. Therefore, in order to enable the pixel circuit to obtain color information of the shooting scene, a color light-transmitting element is generally covered on the pixel circuit to collect color information.

Based on this, the present application also provides a sensor, including a Color Filter Array (CFA for short) and any pixel circuit provided in the present application, wherein the pixel circuit includes a photoelectric conversion module, and the photoelectric conversion module includes a first A photoelectric conversion element and a second photoelectric conversion element, the CFA includes a plurality of color filter units (in the following, one color filter unit is used as an example for description. It can be understood that when the CFA includes at least two color filter units , each of the color filter units can implement the following solution), the color filter unit includes a first light-transmitting element, and the position of the first light-transmitting element is the same as the position of the first photoelectric conversion element. Corresponding to or corresponding to the position of the second photoelectric conversion element, for example, the first light-transmitting element is disposed above the first photoelectric conversion element or above the second photoelectric conversion element. Wherein, the first light transmitting element is a red light transmitting element, a green light transmitting element or a blue light transmitting element.

In the embodiments of the present application, the word "upper" referring to the orientation between elements may indicate that the light will pass through the upper element first, and the word "down" referring to the orientation between the elements may indicate that the light will pass through the lower element afterward. For example, the arrangement of the first light-transmitting element above the first photoelectric conversion element may indicate that the light from the outside will first pass through the first light-transmitting element and then reach the first photoelectric conversion element. Similarly, the arrangement of the first light-transmitting element above the second photoelectric conversion element may indicate that the light from the outside will first pass through the first light-transmitting element and then reach the second photoelectric conversion element.

In the embodiment of the present application, a plurality of pixel circuits constitute a pixel circuit array, and the color filter units in the color filter array CFA correspond one-to-one with the pixel circuits. It can be understood that, a pixel circuit is arranged under each color filter unit. As shown in FIG. 6 , in the sensor, the color filter array 30 includes a plurality of color filter units 20 , a pixel circuit 10 is arranged below each color filter unit 20 , and the plurality of pixel circuits 10 constitute a pixel circuit array .

In one embodiment, the position of the first light-transmitting element corresponds to the position of the first photoelectric conversion element, and the color filter unit further includes a second light-transmitting element, the second light-transmitting element The position corresponds to the position of the second photoelectric conversion element. For example, the first light-transmitting element is disposed above the first photoelectric conversion element, and the second light-transmitting element is disposed above the second photoelectric conversion element.

The color of the light transmitted by the first light-transmitting element may be the same as the color of the light transmitted by the second light-transmitting element. That is to say, when the first light transmitting element is a red light transmitting element, the second light transmitting element is also a red light transmitting element; when the first light transmitting element is a green light transmitting element, the second light transmitting element It is also a green light transmitting element; when the first light transmitting element is a blue light transmitting element, the second light transmitting element is also a blue light transmitting element. As shown in FIG. 7 , a top view of the color filter array CFA in this embodiment is shown. Each color filter unit 20 (indicated by a dashed box) includes a first light-transmitting element 201 and a second light-transmitting element 202, and each first light-transmitting element 201 in the color filter array 30 is a red light-transmitting element (in the figure, the first light-transmitting element 201 is a red light-transmitting element. Represented by R), green light-transmitting element (represented by G in the figure) or blue light-transmitting element (represented by B in the figure); each second light-transmitting element 202 corresponds to the first light-transmitting element 201, and is also red light respectively Light-transmitting element (represented by R in the figure), green light-transmitting element (represented by G in the figure) or blue light-transmitting element (represented by B in the figure).

In this embodiment of the present application, a plurality of first light-transmitting elements 201 (red light-transmitting elements (indicated by R in the figure), green light-transmitting elements (indicated by G in the figure) or blue light-transmitting elements (indicated by B in the figure) Representation)) are respectively arranged above the first photoelectric conversion element and above the second photoelectric conversion element in the plurality of pixel circuits, and then use the first photoelectric conversion element and the second photoelectric conversion element in the pixel circuit to collect the color of the shooting scene information.

That is, an exposure image with color can be obtained based on the first photoelectric conversion element, and an exposure image with color can also be obtained based on the second photoelectric conversion element. Then, when the exposure image obtained based on the first photoelectric conversion element and the exposure image obtained based on the second photoelectric conversion element are fused, the final image obtained by fusion has both details and colors.

It can be understood that the embodiments of the present application do not limit the positional relationship between the first light-transmitting element and the second light-transmitting element, and the shapes of the two. The positional relationship between the first light-transmitting element and the second light-transmitting element in FIG. 7 is , the size relationship, and the shape of the two are just an example to make it easier for the reader to see the color filter distribution. In practical applications, the positional relationship, size relationship and shape of the first light-transmitting element and the second light-transmitting element can be adaptively adjusted according to the positional relationship, size relationship and shape of the first photoelectric conversion element and the second photoelectric conversion element , as long as the first light-transmitting element is arranged above the first photoelectric conversion element, the light passing through the first light-transmitting element can completely cover the photosensitive area of the first photoelectric conversion element, and the second light-transmitting element is arranged on the first photoelectric conversion element. Above the two photoelectric conversion elements, the light passing through the second light-transmitting element can completely cover the photosensitive region of the second photoelectric conversion element. In general, the larger the size of the photoelectric conversion element, the larger the size of the light-transmitting element disposed above it.

On the other hand, since the color of the light transmitted by the first light-transmitting element is the same as the color of the light transmitted by the second light-transmitting element, the first light-transmitting element and the second light-transmitting element can be synthesized as A light-transmitting element (referred to as a replacement light-transmitting element) is disposed above the first photoelectric conversion element and the second photoelectric conversion element. For example, taking FIG. 7 as an example, the first color filter unit includes a first light-transmitting element and a second light-transmitting element, both of which are red light-transmitting elements. A red light-transmitting element smaller than the sum of the size of the first light-transmitting element and the second light-transmitting element replaces the first light-transmitting element and the second light-transmitting element, and directly covers the first photoelectric conversion element and the second photoelectric conversion element. above. The specific size of the replaced red light-transmitting element can be adaptively adjusted according to the layout and positional relationship between the first light-transmitting element and the second light-transmitting element; for example, the first light-transmitting element and the second light-transmitting element are closely arranged , then the size of the replacement light-transmitting element can be equal to the sum of the sizes of the first light-transmitting element and the second light-transmitting element; if the first light-transmitting element and the second light-transmitting element are spaced apart, the size of the replacement light-transmitting element can be larger than the size of the first light-transmitting element and the second light-transmitting element. The sum of the dimensions of the first light-transmitting element and the second light-transmitting element.

In the embodiment of the present application, the size of the first photoelectric conversion element and the second photoelectric conversion element may be further adjusted to adapt to different shooting scenarios. In one embodiment, the size of the first photoelectric conversion element is larger than the size of the second photoelectric conversion element.

Further limiting the size of the first photoelectric conversion element to be larger than the size of the second photoelectric conversion element, the color information obtained by the first photoelectric conversion element is more, and the colors in the exposure image obtained based on the first photoelectric conversion element are also richer. and accurate, which can further improve the color display effect of the final fused image, and is suitable for shooting scenes with greater demand for color performance, such as shooting scenes in the daytime.

Based on the sensor provided by the embodiments of the present application, the present application further provides a method for generating an image by using the sensor provided by the present application, the method comprising:

obtaining a first voltage value after the first photoelectric conversion element has been photosensitive;

obtaining a second voltage value after the second photoelectric conversion element has been photosensitive;

generating a plurality of pictures with different exposure ratios based on the first voltage value and the second voltage value;

Based on the generated plurality of pictures, a target image is generated.

Specifically, first, the voltage corresponding to the first photoelectric conversion element after being exposed to light is read. When the first photoelectric conversion control switch is closed, the charge generated by the first photoelectric conversion element is transferred to the first capacitor, the source follower records the voltage U1 of the first capacitor, the column selection signal switch is closed, and the voltage value U1 is output through the Vout circuit. That is, the first voltage value after the first photoelectric conversion element is photosensitive. Further, based on this voltage, an exposure image corresponding to the first photoelectric conversion element after being exposed to light is obtained.

Then, the voltage corresponding to the second photoelectric conversion element after being exposed to light is read. When the second photoelectric conversion control switch is closed, the charge generated by the second photoelectric conversion element is transferred to the first capacitor, the source follower records the voltage U2 of the first capacitor, the column selection signal switch is closed, and the voltage value U2 is output through the Vout circuit. That is, the second voltage value after the second photoelectric conversion element is light-sensitive. Further, based on this voltage, an exposure image corresponding to the second photoelectric conversion element after being exposed to light is obtained.

Finally, the obtained multiple exposure images are fused to obtain the target image.

Wherein, when the number of capacitors in the capacitor module is multiple, the first voltage value is actually a set of voltage values, and the second voltage value is also a set of voltage values. For example, when the capacitor module includes a first capacitor and a second capacitor, first, the first voltage value corresponding to the first photoelectric conversion element after being light-sensitive is read. Close the first photoelectric conversion control switch, open the first capacitor control switch, read the voltage on the first capacitor, and obtain the first exposure image corresponding to the first photoelectric conversion element after being photosensitive; then close the first capacitor control switch, read Taking the voltages on the first capacitor and the second capacitor connected in parallel, the second exposure image corresponding to the first photoelectric conversion element after being exposed to light is obtained. That is, the first voltage value corresponding to the first photoelectric conversion element after exposure to light actually includes the voltage corresponding to the first exposure image obtained after exposure to the first photoelectric conversion element, and the voltage value obtained after exposure to the first photoelectric conversion element. The voltage corresponding to the second exposure image. Then, read the voltage corresponding to the second photoelectric conversion unit after being photosensitive. Close the second photoelectric conversion control switch (the first photoelectric conversion control switch is in the off state at this time), open the first capacitor control switch, read the voltage on the first capacitor, and obtain the corresponding first photoelectric conversion element after the second photoelectric conversion element is photosensitive. An exposure image; then close the first capacitor control switch, read the voltages on the first capacitor and the second capacitor connected in parallel, and obtain the second exposure image corresponding to the second photoelectric conversion element after being photosensitive. That is, the second voltage value corresponding to the second photoelectric conversion element after exposure to light actually includes the voltage corresponding to the first exposure image obtained after exposure to the second photoelectric conversion element, and the voltage obtained after exposure to the second photoelectric conversion element. The voltage corresponding to the second exposure image.

Before acquiring the first voltage value after the first photoelectric conversion element has been photosensitive, the method further includes:

Empty the residual charges in the first photoelectric conversion element and the second photoelectric conversion element;

Empty the charge of each capacitor in the capacitor module.

Specifically, the first photoelectric conversion control switch and the second photoelectric conversion control switch are kept disconnected, the reset switch is closed, the power supply voltage is loaded on each capacitor, and the residual charge on each capacitor is emptied.

In addition, the present application also provides a camera module 40 including the sensor. As shown in FIG. 9 , the camera module 40 includes a protective film 401, a lens (Lens) 402, a voice coil motor (Voice Coil Motor) 403, a support Component 404 , infrared filter (IR Filter) 405 , sensor 406 provided by this application, flexible board (FPC) 407 , and connection component 408 .

Among them, the lens (Lens) is used for focusing and focusing, the lens is wrapped and fixed by the voice coil motor, and the upper and lower ends of the voice coil motor are linked with the shrapnel. When focusing, the motor generates an electromagnetic force by energizing, which is finally balanced with the elastic force of the shrapnel. The position of the motor can be controlled by the size of the energization, and then the lens is pushed to the focus position by the motor. The function of the infrared filter is to filter out the unnecessary light projected to the sensor. The light passing through the infrared filter can be perceived by the sensor, preventing the sensor from producing false color/moire, and improving its resolution and color reproduction.

The voice coil motor includes an upper cover, an upper spring piece, a lower spring piece, a housing, a coil, a magnet, a moving part, a base, and a terminal. Among them, the upper cover plays the role of protecting the motor; the upper spring sheet, when deformed, exerts a force on the motor, and the sum of the lower spring sheet balances the electromagnetic force; the outer casing is the main frame of the fixed part of the motor, which has a magnetic conductivity and can improve the magnetism. When the coil is energized, an upward thrust is generated under the action of the magnetic field of the magnet, which drives other parts of the moving part to move together; the magnet generates a magnetic field, so that the energized coil generates an electromagnetic force under the action of its magnetic field, so that the moving parts carrier Move with the lens; when the lower spring is deformed, it exerts a force on the motor, and the sum of the upper spring balances the electromagnetic force; the base and the motor are directly assembled with the soft board; the mobile phone supplies power to the motor through the terminal.

In the description of this specification, reference to the terms "one embodiment," "some embodiments," "exemplary embodiment," "example," "specific example," or "some examples", etc., is meant to incorporate the embodiments A particular feature, structure, material, or characteristic described by an example or example is included in at least one embodiment or example of the present application. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

Although the embodiments of the present application have been shown and described, it will be understood by those of ordinary skill in the art that various changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the present application, The scope of the application is defined by the claims and their equivalents.

Claims

A sensor, which includes a color filter array and a pixel circuit, the pixel circuit includes a photoelectric conversion module, the photoelectric conversion module includes a first photoelectric conversion element and a second photoelectric conversion element, and the color filter array includes multiple a color filter unit, the color filter unit includes a first light-transmitting element, and the position of the first light-transmitting element corresponds to the position of the first photoelectric conversion element or the position of the second photoelectric conversion element. Correspondingly in position, the first light transmitting element is a red light transmitting element, a green light transmitting element or a blue light transmitting element.
The sensor according to claim 1, wherein the position of the first light-transmitting element corresponds to the position of the first photoelectric conversion element, the color filter unit further comprises a second light-transmitting element, the first light-transmitting element The positions of the two light-transmitting elements correspond to the positions of the second photoelectric conversion elements.
The sensor according to claim 2, wherein the size of the first photoelectric conversion element is larger than the size of the second photoelectric conversion element.
The sensor according to claim 2 or 3, wherein the color of the light transmitted by the first light-transmitting element is the same as the color of the light transmitted by the second light-transmitting element.
The sensor according to claim 4, wherein the first light transmitting element is a red light transmitting element, and the second light transmitting element is a red light transmitting element.
The sensor according to claim 4, wherein the first light transmitting element is a green light transmitting element, and the second light transmitting element is a green light transmitting element.
The sensor according to claim 4, wherein the first light transmitting element is a blue light transmitting element, and the second light transmitting element is a blue light transmitting element.
The sensor according to claim 1, wherein the pixel circuit further comprises a capacitance module and a reset switch,

The capacitor module includes a first capacitor, a first end of the first capacitor is grounded, and a second end of the first capacitor is connected to the first end of the reset switch;

The first photoelectric conversion element and the second photoelectric conversion element are connected in parallel; the first end of the first photoelectric conversion element is grounded, and the second end of the first photoelectric conversion element is connected to the reset switch the first end; the first end of the second photoelectric conversion element is grounded, and the second end of the second photoelectric conversion element is connected to the first end of the reset switch.
The sensor of claim 8, wherein the photoelectric conversion module further comprises at least one of a first photoelectric conversion control switch and a second photoelectric conversion control switch;

When the photoelectric conversion module includes a first photoelectric conversion control switch, the first end of the first photoelectric conversion control switch is connected to the second end of the first photoelectric conversion element, and the first photoelectric conversion control switch is connected to the second end of the first photoelectric conversion element. the second end of the control switch is connected to the first end of the reset switch;

When the photoelectric conversion module includes a second photoelectric conversion control switch, the first end of the second photoelectric conversion control switch is connected to the second end of the second photoelectric conversion element, and the second photoelectric conversion The second end of the control switch is connected to the first end of the reset switch.
The sensor according to claim 8, wherein the capacitor module further comprises a second capacitor connected in parallel with the first capacitor; a first end of the second capacitor is grounded, and a second end of the second capacitor is grounded connecting the first end of the reset switch;

The capacitor module further includes a first capacitor control switch connected in parallel with the first capacitor, a first end of the first capacitor control switch is connected to a second end of the second capacitor, and the first capacitor control switch The second end of the reset switch is connected to the first end of the reset switch.
The sensor according to claim 10, wherein the capacitor module further comprises a third capacitor connected in parallel with the first capacitor and the second capacitor, a first end of the third capacitor is grounded, and the first capacitor is connected to the ground. The second end of the three capacitors is connected to the first end of the reset switch;

The capacitor module further includes a second capacitor control switch connected in parallel with the first capacitor and the second capacitor, respectively, and a first end of the second capacitor control switch is connected to a second end of the third capacitor, The second end of the second capacitance control switch is connected to the first end of the reset switch.