Pixel circuit, image sensor, camera module, device and image generation method

Abstract

The application discloses a pixel circuit, an image sensor, a camera module, an equipment and an image generation method, and belongs to the technical field of camera shooting. The pixel circuit comprises a plurality of rows and columns of pixel units and a plurality of signal readout units; the input ends of the plurality of signal readout units are electrically connected with the plurality of rows of pixel units one by one; the output ends of the plurality of signal readout units are electrically connected with a plurality of analog-to-digital converters one by one; the signal readout units are used for reading out voltage signals corresponding to each row of pixel units to the analog-to-digital converters; each pixel unit comprises a high dynamic range readout subunit and n rows and n columns of pixel subunits, wherein n is a positive integer greater than or equal to 2, and the pixel subunits included in the same pixel unit correspond to the same color; the first end of the high dynamic range readout subunit is electrically connected with the positive electrode of a photosensitive element included in the pixel subunit; the second end of the high dynamic range readout subunit is electrically connected with the analog-to-digital converter, and the high dynamic range readout subunit is used for outputting a high dynamic range image.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of camera shooting, and particularly relates to a pixel circuit, an image sensor, a camera module, a device and an image generation method. BACKGROUND

[0002] At present, the market competition of mobile terminal products is increasingly fierce, especially in the aspect of photographing of smart phones, the mobile terminals of various brands are extremely fierce, mainly in the aspect of dynamic range improvement of images.

[0003] In the related art, a multi-exposure multi-frame fusion manner is mainly used to improve the dynamic range of an image, so as to obtain a high dynamic range (HDR) image. However, the multi-exposure multi-frame fusion manner will cause motion blur of a moving object in shooting. SUMMARY

[0004] Embodiments of the application aim to provide a pixel circuit, an image sensor, a camera module, a device and an image generation method, which can improve the dynamic range of an image and do not cause motion blur.

[0005] In a first aspect, an embodiment of the application provides a pixel circuit, comprising: a plurality of rows and a plurality of columns of pixel units and a plurality of signal readout units.

[0006] The input ends of the plurality of signal readout units are electrically connected one by one with the plurality of rows of pixel units.

[0007] The output ends of the plurality of signal readout units are electrically connected one by one with a plurality of analog-to-digital converters; and the signal readout units are configured to read out voltage signals corresponding to each row of pixel units to the analog-to-digital converters.

[0008] Each pixel unit comprises a high dynamic range readout subunit and n rows and n columns of pixel subunits, wherein n is a positive integer greater than or equal to 2, and the pixel subunits included in the same pixel unit correspond to the same color.

[0009] The first end of the high dynamic range readout subunit is electrically connected with the anode of a light sensing element included in the pixel subunit.

[0010] The second end of the high dynamic range readout subunit is electrically connected with the analog-to-digital converter, and the high dynamic range readout subunit is configured to output a high dynamic range image.

[0011] In a second aspect, an embodiment of the application provides an image sensor, comprising:

[0012] The pixel circuit provided by the embodiment of the application.

[0013] In a third aspect, an embodiment of the application provides a camera module, comprising:

[0014] The image sensor provided in the embodiments of the present application.

[0015] In a fourth aspect, the embodiments of the present application provide an electronic device, comprising:

[0016] The camera module provided in the embodiments of the present application.

[0017] In a fifth aspect, the embodiments of the present application provide an image generation method, applied to the electronic device provided in the embodiments of the present application, and the method comprises:

[0018] When it is necessary to enhance the high dynamic range of the image, the voltage signal of the anode of the photosensitive element in the n rows and n columns of pixel subunits is acquired;

[0019] According to the voltage signal, a first image is generated.

[0020] In the embodiments of the present application, the pixel circuit comprises a plurality of rows and a plurality of columns of pixel units and a plurality of signal readout units; the input ends of the plurality of signal readout units are electrically connected to the plurality of rows of pixel units one by one; the output ends of the plurality of signal readout units are electrically connected to a plurality of analog-to-digital converters one by one; the signal readout unit is used to read out the voltage signal corresponding to each row of pixel units to the analog-to-digital converter; each pixel unit comprises a high dynamic range readout subunit and n rows and n columns of pixel subunits, wherein n is a positive integer greater than or equal to 2, and the pixel subunits included in the same pixel unit correspond to the same color; the first end of the high dynamic range readout subunit is electrically connected to the anode of the photosensitive element included in the pixel subunit; the second end of the high dynamic range readout subunit is electrically connected to the analog-to-digital converter, and the high dynamic range readout subunit is used to output a high dynamic range image. By reading the voltage signal of the anode of the photosensitive element in the n rows and n columns of pixel subunits, an image is generated according to the voltage signal of the anode of the photosensitive element in the n rows and n columns of pixel subunits, which can improve the high dynamic range of the image and does not produce motion blur, effectively improving the image quality. BRIEF DESCRIPTION OF DRAWINGS

[0021] Figure 1 is a first structure diagram of the pixel circuit provided in the embodiments of the present application;

[0022] Figure 2 is a first structure diagram of the pixel unit provided in the embodiments of the present application;

[0023] Figure 3 is a second structure diagram of the pixel unit provided in the embodiments of the present application;

[0024] Figure 4 is a third structure diagram of the pixel unit provided in the embodiments of the present application;

[0025] Figure 5is a fourth structural schematic diagram of a pixel unit provided by an embodiment of the present application;

[0026] Figure 6 is a fifth structural schematic diagram of a pixel unit provided by an embodiment of the present application;

[0027] Figure 7 is a second structural schematic diagram of a pixel circuit provided by an embodiment of the present application;

[0028] Figure 8 is a specific structural schematic diagram of a pixel unit provided by an embodiment of the present application;

[0029] Figure 9 is a flow schematic diagram of an image generation method of an embodiment of the present application;

[0030] Figure 10 is a hardware structural schematic diagram of an electronic device implementing an embodiment of the present application. DETAILED DESCRIPTION

[0031] The technical solutions in the embodiments of the present application will be clearly described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, but not all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art belong to the scope of protection of the present application.

[0032] The terms "first", "second", and the like in the specification and claims of the present application are used to distinguish similar objects, and are not used to describe a specific order or sequence. It should be understood that the terms used in this way can be interchanged under appropriate circumstances, so that the embodiments of the present application can be implemented in an order other than that illustrated or described herein, and the objects distinguished by "first", "second", and the like are generally of a kind and are not limited in number, for example, the first object can be one or more. In addition, "and / or" in the specification and claims indicates at least one of the connected objects, and the character " / ", generally indicates that the front and rear associated objects are in an "or" relationship.

[0033] The pixel circuit, image sensor, camera module, device and image generation method provided by the embodiments of the present application will be described in detail below in conjunction with the drawings, through specific embodiments and their application scenarios.

[0034] The pixel circuit provided by the embodiment of the present application includes multiple rows and columns of pixel units and multiple signal readout units; the input ends of the multiple signal readout units are electrically connected one by one to the multiple rows of pixel units; the output ends of the multiple signal readout units are electrically connected one by one to the multiple analog-to-digital converters; the signal readout unit is used to read out the voltage signal corresponding to each row of pixel units to the analog-to-digital converter, the analog-to-digital converter is connected to the image processor, and the image processor generates an image based on the digital signal generated by the analog-to-digital converter.

[0035] In some possible implementations of the embodiments of the present application, the multiple rows and columns of pixel units in the embodiments of the present application are pixel units in at least two rows and at least two columns.

[0036] like Figure 1 As shown, Figure 1 This is a schematic diagram of the first structure of the pixel circuit provided in the embodiment of the present application. Figure 1 In the figure, the pixel circuit 100 includes multiple rows and columns of pixel units 11 and multiple signal readout units 12; the input ends of the multiple signal readout units 12 are electrically connected one by one to the multiple rows of pixel units 11; the output ends of the multiple signal readout units 13 are electrically connected one by one to the multiple analog-to-digital converters 200; the analog-to-digital converter 200 converts the sampled voltage signal of each row of pixel units into a digital signal, and the image processor generates an image based on the digital signal generated by the analog-to-digital converter 200.

[0037] In some possible implementations of the embodiments of the present application, each pixel unit in the embodiments of the present application includes a high dynamic range readout subunit and n rows and n columns of pixel subunits, where n is a positive integer greater than or equal to 2, and the pixel subunits included in the same pixel unit have the same color; a first end of the high dynamic range readout subunit is electrically connected to the positive electrode of the photosensitive element included in the pixel subunit; a second end of the high dynamic range readout subunit is electrically connected to the analog-to-digital converter, and the high dynamic range readout subunit is used to output a high dynamic range image.

[0038] It can be understood that when n is 2, the pixel unit is a four-in-one pixel unit, when n is 3, the pixel unit is a nine-in-one pixel unit, and when n is 4, the pixel unit is a sixteen-in-one pixel unit.

[0039] The colors corresponding to the pixel sub-units included in the same pixel unit can be red, red-green, cyan, or blue.

[0040] like Figure 2 As shown, Figure 2 This is a schematic diagram of the first structure of the pixel unit provided in the embodiment of the present application. Figure 2In the embodiment, the pixel unit 11 includes a high dynamic range readout subunit 112 and n rows and n columns of pixel subunits 111. A first terminal of the high dynamic range readout subunit 112 is electrically connected to the positive electrode of the photosensitive element PD included in the pixel subunit 111; a second terminal of the high dynamic range readout subunit 112 is electrically connected to the analog-to-digital converter 200.

[0041] In some possible implementations of the embodiments of the present application, the pixel sub-unit includes a first switching tube, a photosensitive element and a second switching tube; the negative electrode of the photosensitive element is electrically connected to the source electrode of the first switching tube; the drain electrode of the first switching tube is electrically connected to the signal readout unit corresponding to the pixel unit including the photosensitive element; and the positive electrode of the photosensitive element is electrically connected to the drain electrode of the second switching tube.

[0042] like Figure 3 As shown, Figure 3 This is a schematic diagram of the second structure of the pixel unit provided in the embodiment of the present application. Figure 3 In the figure, the pixel sub-unit 111 includes a first switching tube TG1, a photosensitive element PD and a second switching tube TG2; the cathode of the photosensitive element PD is electrically connected to the source of the first switching tube TG1; the drain of the first switching tube TG1 is electrically connected to the signal readout unit 12 corresponding to the pixel unit including the photosensitive element PD; the anode of the photosensitive element PD is electrically connected to the drain of the second switching tube TG2; and the source of the second switching tube TG2 is grounded.

[0043] In some possible implementations of the embodiments of the present application, the high dynamic range readout subunit may include a third switching tube and a first capacitor; the drain of the third switching tube is electrically connected to the positive electrode of the photosensitive element of the pixel subunit; the source of the third switching tube is electrically connected to the first plate of the first capacitor; and the second plate of the first capacitor is grounded.

[0044] like Figure 4 As shown, Figure 4 This is a third structural diagram of a pixel unit provided in an embodiment of the present application. Figure 4 In the high dynamic range readout subunit 112, a third switching transistor TG3 and a first capacitor C1 are included. The drain of the third switching transistor TG3 is electrically connected to the positive electrode of the photosensitive element PD of the pixel subunit 111. The source of the third switching transistor TG3 is electrically connected to the first plate of the first capacitor C1 and the analog-to-digital converter 200. The second plate of the first capacitor C1 is grounded.

[0045] In some possible implementations of the embodiments of the present application, the high dynamic range readout subunit may further include: a fourth switch tube; the drain of the fourth switch tube is connected to the power supply; and the source of the fourth switch tube is electrically connected to the first plate of the first capacitor.

[0046] like Figure 5 As shown, Figure 5This is a fourth structural diagram of a pixel unit provided in an embodiment of the present application. Figure 5 In the high dynamic range readout subunit 112, a third switching transistor TG3, a first capacitor C1, and a fourth switching transistor TG4. The drain of the third switching transistor TG3 is electrically connected to the positive electrode of the photosensitive element PD of the pixel subunit 111; the source of the third switching transistor TG3 is electrically connected to the first plate of the first capacitor C1, the source of the fourth switching transistor TG4, and the analog-to-digital converter 200; the drain of the fourth switching transistor is connected to the power supply VDD; and the second plate of the first capacitor C1 is grounded.

[0047] When the fourth switch tube TG4 is turned on, the first capacitor C1 is cleared.

[0048] In some possible implementations of the embodiments of the present application, the high dynamic range readout subunit may further include: a first signal amplifier and a first row selector; the drain of the first signal amplifier is connected to the power supply; the source of the first signal amplifier is electrically connected to the drain of the row selector; the gate of the first signal amplifier is electrically connected to the first plate of the first capacitor; and the source of the first row selector is electrically connected to the analog-to-digital converter.

[0049] like Figure 6 As shown, Figure 6 This is a fifth structural diagram of a pixel unit provided in an embodiment of the present application. Figure 6 In the figure, the high dynamic range readout subunit 112 includes a third switch tube TG3, a first capacitor C1, a first signal amplifier TG5 and a first row selector TG6. The drain of the third switch tube TG3 is electrically connected to the positive electrode of the photosensitive element PD of the pixel subunit 111; the source of the third switch tube TG3 is electrically connected to the first plate of the first capacitor C1 and the gate of the first signal amplifier TG5 respectively; the second plate of the first capacitor C1 is grounded; the drain of the first signal amplifier TG5 is connected to the power supply VDD; the source of the first signal amplifier TG5 is electrically connected to the drain of the first row selector TG6; and the source of the first row selector TG6 is electrically connected to the analog-to-digital converter 200.

[0050] The voltage signal of the first capacitor C1 is amplified by the first signal amplifier TG5 and the first row selector TG6 and then transmitted to the analog-to-digital converter for reading.

[0051] In some possible implementations of the embodiments of the present application, the signal readout unit may include: a reset transistor, a parasitic capacitor, a second signal amplifier and a second row selector; the gate of the second signal amplifier is electrically connected to the negative electrode of the photosensitive element included in the pixel sub-unit, the first plate of the parasitic capacitor, and the source of the reset transistor, respectively; the drain of the second signal amplifier and the drain of the reset transistor are both connected to the power supply; the source of the second signal amplifier is electrically connected to the drain of the second row selector; and the source of the second row selector is electrically connected to the analog-to-digital converter.

[0052] As Figure 7 shown, Figure 7 is a second structure diagram of a pixel circuit provided in the embodiments of the present application. In Figure 7 , the signal readout unit 12 includes a reset transistor RST, a parasitic capacitor FD, a second signal amplifier SF and a second row selector SET. The gate of the second signal amplifier SF is electrically connected with the negative electrode of the photosensitive element PD included in the pixel subunit 111, the first plate of the parasitic capacitor FD and the source of the reset transistor RST respectively; the drain of the second signal amplifier SF and the drain of the reset transistor RST are both connected with the power supply VDD; the source of the second signal amplifier SF is electrically connected with the drain of the second row selector SET; and the source of the second row selector SET is electrically connected with the analog-to-digital converter 200.

[0053] Figure 8 is a specific structure diagram of a pixel unit provided in the embodiments of the present application.

[0054] In Figure 8 , the pixel unit 11 includes a high dynamic range readout subunit 112 and a 2-row 2-column pixel subunit 111. The pixel subunit 111 includes a first switch tube TG1, a second switch tube TG2 and a photosensitive element PD; the high dynamic range readout subunit 112 includes a third switch tube TG3, a first capacitor C1, a fourth switch tube TG4, a first signal amplifier TG5 and a first row selector TG6; and the signal readout unit 12 includes a reset transistor RST, a parasitic capacitor FD, a second signal amplifier SF and a second row selector SET.

[0055] The 2-row 2-column pixel subunit includes an upper left pixel subunit, an upper right pixel subunit, a lower left pixel subunit and a lower right pixel subunit.

[0056] In some possible implementations in the embodiments of the present application, the switch tubes, the signal amplifiers, the row selectors and the reset transistors in the embodiments of the present application can be metal-oxide-semiconductor field-effect transistors (MOSFETs).

[0057] The negative electrode of the photosensitive element PD is electrically connected with the source electrode of the first switch tube TG1; the drain electrode of the first switch tube TG1 is electrically connected with the drain electrode of the reset triode RST, the first plate of the parasitic capacitor FD and the gate electrode of the second signal amplifier SF respectively, the second plate of the parasitic capacitor FD is grounded, the source electrode of the reset triode RST and the source electrode of the second signal amplifier SF are connected with the power supply VDD, the drain electrode of the second signal amplifier SF is electrically connected with the source electrode of the second row selector SET; the drain electrode of the second row selector SET is electrically connected with the positive electrode of the direct current power supply DC and the analog-digital converter 200 respectively; the positive electrode of the photosensitive element PD is electrically connected with the drain electrode of the second switch tube TG2; the source electrode of the second switch tube TG2 is grounded.

[0058] The drain electrode of the third switch tube TG3 is electrically connected with the positive electrode of the photosensitive element PD of each row of pixel sub-units; the source electrode of the third switch tube TG3 is electrically connected with the first plate of the first capacitor C1, the source electrode of the fourth switch tube TG4 and the gate electrode of the first signal amplifier TG5 respectively; the drain electrode of the fourth switch tube TG4 and the drain electrode of the first signal amplifier TG5 are electrically connected with the power supply VDD; the source electrode of the first signal amplifier TG5 is electrically connected with the drain electrode of the first row selector TG6; the source electrode of the first row selector TG6 is electrically connected with the analog-digital converter 200.

[0059] When the pixels are exposed to light, the reset triode RST, the fourth switch tube TG4 and the first switch tube TG1 included in each pixel sub-unit are turned on, and the first capacitor C1 and the parasitic capacitor FD are emptied. The electron-hole pairs generated by the light irradiation will be separated due to the electric field of the photosensitive element PD, and the electrons will move to the N region and the holes will move to the P region. After the exposure is completed, the reset triode RST is turned off, and the parasitic capacitor FD is reset to a high level. After the reset is completed, the reset level of the parasitic capacitor FD is read out through the second signal amplifier SF and the second row selector SET, and the signal read at this time is stored as a voltage signal value A.

[0060] When it is necessary to generate an image in a regular pixel mode, the first switch tube TG1 included in each pixel sub-unit is turned on, and the charges are completely transferred from the photosensitive region to the parasitic capacitor FD for a second reading. The voltage signal of the parasitic capacitor FD is read out for a second time through the second signal amplifier SF and the second row selector SET, and the signal read at this time is stored as a voltage signal value B. The two stored voltage signal values are subtracted, and the obtained voltage signal is the voltage value corresponding to the pure light signal. After the voltage value is subjected to analog amplification and sampling by the analog-digital converter 200, the digital signal corresponding to the light signal is obtained. The analog-digital converter 200 sends the digital signal corresponding to the light signal of each photosensitive element to the image processor 300, and the image processor 300 generates an image.

[0061] When a high definition image is needed, the first switch TG1 at the negative terminal of the photosensitive element included in the upper left pixel subunit is closed, and the charge of the photosensitive element included in the upper left pixel subunit is transferred from the photosensitive region to the parasitic capacitor FD for a second readout. At this time, the voltage of the parasitic capacitor FD drops due to the charge injection of the photosensitive element included in the upper left pixel subunit. The voltage signal of the parasitic capacitor FD is output to the analog-to-digital converter 200 through the second signal amplifier SF and the second row selector SET. The first switch TG1 at the negative terminal of the photosensitive element included in the upper left pixel subunit is opened, and the first switch TG1 at the negative terminal of the photosensitive element included in the upper right pixel subunit is closed. The charge of the photosensitive element included in the upper right pixel subunit is transferred from the photosensitive region to the parasitic capacitor FD for a second readout. At this time, the voltage of the parasitic capacitor FD drops due to the charge injection of the photosensitive element included in the upper right pixel subunit. The voltage signal of the parasitic capacitor FD is output to the analog-to-digital converter 200 through the second signal amplifier SF and the second row selector SET. The first switch TG1 at the negative terminal of the photosensitive element included in the upper right pixel subunit is opened, and the first switch TG1 at the negative terminal of the photosensitive element included in the lower left pixel subunit is closed. The charge of the photosensitive element included in the lower left pixel subunit is transferred from the photosensitive region to the parasitic capacitor FD for a second readout. At this time, the voltage of the parasitic capacitor FD drops due to the charge injection of the photosensitive element included in the lower left pixel subunit. The voltage signal of the parasitic capacitor FD is output to the analog-to-digital converter 200 through the second signal amplifier SF and the second row selector SET. The first switch TG1 at the negative terminal of the photosensitive element included in the lower left pixel subunit is opened, and the first switch TG1 at the negative terminal of the photosensitive element included in the lower right pixel subunit is closed. The charge of the photosensitive element included in the lower right pixel subunit is transferred from the photosensitive region to the parasitic capacitor FD for a second readout. At this time, the voltage of the parasitic capacitor FD drops due to the charge injection of the photosensitive element included in the lower right pixel subunit. The voltage signal of the parasitic capacitor FD is output to the analog-to-digital converter 200 through the second signal amplifier SF and the second row selector SET. At this time, the digital signals of the four photosensitive elements are obtained, and thus the definition of the image can be improved.

[0062] When a high dynamic range image needs to be generated, the second switch tube TG2 connected to the positive electrode of the photosensitive element in the upper left pixel sub-unit, the second switch tube TG2 connected to the positive electrode of the photosensitive element in the upper right pixel sub-unit, the second switch tube TG2 connected to the positive electrode of the photosensitive element in the lower left pixel sub-unit, and the second switch tube TG2 connected to the positive electrode of the photosensitive element in the lower right pixel sub-unit are turned off, and the third switch tube TG3 and the fourth switch tube TG4 are turned on. The positive holes of the photosensitive elements in the upper left pixel sub-unit, the photosensitive elements in the upper right pixel sub-unit, the photosensitive elements in the lower left pixel sub-unit, and the photosensitive elements in the lower right pixel sub-unit are all transmitted to the first capacitor C1, at this time, the voltage of the first capacitor C1 rises, and the voltage signal of the first capacitor C1 is transmitted to the analog-to-digital converter 200 through the first signal amplifier TG5 and the first row selector TG6 for reading, and the obtained voltage signal is the sum of the voltage signals of the four photosensitive elements, and since the voltage of the first capacitor C1 is much greater than the voltage of the parasitic capacitor FD, the dynamic range of the image generated by the image processor will be very large.

[0063] In the embodiment of the present application, the image is generated by the electrical signal of the positive electrode of the photosensitive element, a large dynamic range image can be generated, the high dynamic range of the image can be improved, and motion blur is not generated, effectively improving the image quality.

[0064] The positive electrode and the negative electrode of the pixel sub-unit in the embodiment of the present application can output two kinds of voltage signals, the two kinds of voltage signals are output in different ways, which can enable the sensor to simultaneously acquire an image with high definition and good signal-to-noise ratio in a polar night environment or a high dynamic range scene, effectively improving the user's shooting experience.

[0065] The embodiment of the present application further provides an image sensor comprising the pixel circuit provided by the embodiment of the present application.

[0066] The embodiment of the present application further provides a camera module comprising the image sensor provided by the embodiment of the present application.

[0067] The embodiment of the present application further provides an electronic device comprising the camera module provided by the embodiment of the present application.

[0068] The electronic device in the embodiments of the present application may be a terminal or other device other than a terminal. For example, the electronic device may be a mobile phone, a tablet computer, a laptop computer, a PDA, an in-vehicle electronic device, a mobile internet device (MID), an augmented reality (AR) / virtual reality (VR) device, a robot, a wearable device, an ultra-mobile personal computer (UMPC), a netbook, or a personal digital assistant (PDA), etc. It may also be a server, a network attached storage (NAS), a personal computer (PC), a television (TV), an ATM, or an kiosks, etc., and the embodiments of the present application do not specifically limit it.

[0069] The electronic device in the embodiment of the present application may be an electronic device having an operating system. The operating system may be an Android operating system, an iOS operating system, or other possible operating systems, which are not specifically limited in the embodiment of the present application.

[0070] The embodiment of the present application also provides an image generation method, which is applied to the electronic device provided in the embodiment of the present application.

[0071] Figure 9 : is a flow chart of an image generation method provided in an embodiment of the present application. The image generation method may include the following steps:

[0072] Step 901: When it is necessary to enhance the high dynamic range of an image, obtain the voltage signal of the positive electrode of the photosensitive element in the pixel sub-unit of n rows and n columns;

[0073] In some possible implementations of the embodiments of the present application, step 901 may include: disconnecting the switching tube electrically connected to the positive electrode of the photosensitive element in the pixel sub-unit of n rows and n columns; transmitting the voltage signal of the positive electrode of the photosensitive element in the pixel sub-unit of n rows and n columns to the analog-to-digital converter for reading through the high dynamic range readout sub-unit, and obtaining a voltage signal that combines the voltage signals of the positive electrode of the photosensitive element in the pixel sub-unit of n rows and n columns.

[0074] For example, the connection between the high dynamic range readout subunit and the positive electrode of the photosensitive element included in the 2 rows and 2 columns of pixel subunits is used as an example for description. The 2 rows and 2 columns of pixel subunits include an upper left pixel subunit, an upper right pixel subunit, a lower left pixel subunit, and a lower right pixel subunit.

[0075] The second switch tube connected to the positive electrode of the photosensitive element included in the left upper pixel sub-unit, the second switch tube connected to the positive electrode of the photosensitive element included in the right upper pixel sub-unit, the second switch tube connected to the positive electrode of the photosensitive element included in the left lower pixel sub-unit, and the second switch tube connected to the positive electrode of the photosensitive element included in the right lower pixel sub-unit are closed, and the third switch tube and the fourth switch tube included in the high dynamic range readout sub-unit are closed. All the holes of the four photosensitive elements, including the photosensitive element included in the left upper pixel sub-unit, the photosensitive element included in the right upper pixel sub-unit, the photosensitive element included in the left lower pixel sub-unit, and the photosensitive element included in the right lower pixel sub-unit, are transmitted to the first capacitor included in the high dynamic range readout sub-unit, and at this time, the voltage of the first capacitor rises, and the voltage signal of the first capacitor is transmitted to the analog-to-digital converter for reading by the first signal amplifier and the first row selector included in the high dynamic range readout sub-unit, and the voltage signal obtained is the sum of the voltage signals of the four photosensitive elements, that is, the total signal of four same-color pixels combined together. Since the voltage of the first capacitor is much greater than the voltage of the parasitic capacitor, the dynamic range of the image generated by the image processor will be very large.

[0076] Step 902: generating a first image according to the voltage signal.

[0077] In the embodiments of the present application, the image is generated by the electrical signal of the positive electrode of the photosensitive element, a large dynamic range image can be generated, the high dynamic range of the image can be improved, and motion blur does not occur, effectively improving the image quality.

[0078] In some possible implementations of the embodiments of the present application, the image generation method provided by the embodiments of the present application can further include: when it is necessary to enhance the clarity of the image, closing the switch tube electrically connected to the negative electrode of the photosensitive element in the n rows and n columns of pixel sub-units; transmitting the voltage signal of the negative electrode of the photosensitive element in each row of pixel sub-units to the analog-to-digital converter for reading by the signal readout unit, to obtain the voltage signal corresponding to each row of pixel sub-units; and generating a second image according to the voltage signal corresponding to each row of pixel sub-units.

[0079] When a high-definition image needs to be generated, the first switch tube at the negative electrode end of the photosensitive element included in the upper left pixel sub-unit is closed, and the charge of the photosensitive element included in the upper left pixel sub-unit is transferred from the photosensitive region to the parasitic capacitor for a second readout. At this time, the voltage of the parasitic capacitor decreases due to the charge injection of the photosensitive element included in the upper left pixel sub-unit. The voltage signal of the parasitic capacitor is output to the analog-to-digital converter through the second signal amplifier and the second row selector. The processing processes of the photosensitive element included in the upper right pixel sub-unit, the photosensitive element included in the lower left pixel sub-unit, and the photosensitive element included in the lower right pixel sub-unit are similar to the processing process of the photosensitive element included in the upper left pixel sub-unit. Details are not described herein. In this way, the photoelectric signal of a row of pixels can be obtained. The processing processes of the second row to the last row are similar to the processing process of the first row. Details are not described herein.

[0080] In the embodiment of the present application, a high-definition image can be obtained.

[0081] The positive electrode and the negative electrode of the pixel sub-unit in the embodiment of the present application can output two voltage signals. The two voltage signals are output in different ways, so that the sensor can obtain an image with a high dynamic range or high definition. In a high dynamic range scene, the photographing effect and user experience can be effectively improved.

[0082] Figure 10 FIG. 1 is a schematic diagram of the hardware structure of an electronic device for implementing the embodiment of the present application.

[0083] The electronic device 1000 includes, but is not limited to, a radio frequency unit 1001, a network module 1002, an audio output unit 1003, an input unit 1004, a sensor 1005, a display unit 1006, a user input unit 1007, an interface unit 1008, a memory 1009, and a processor 1010.

[0084] Those skilled in the art can understand that the electronic device 1000 can also include a power supply (such as a battery) for powering each component. The power supply can be logically connected to the processor 1010 through a power management system, so as to realize functions such as management of charging, discharging, and power consumption management through the power management system. Figure 10 The electronic device structure shown in FIG. 1 does not constitute a limitation on the electronic device. The electronic device can include more or fewer components than shown, or combine certain components, or have a different arrangement of components, which will not be described herein.

[0085] In the embodiment of the present application, the electronic device 1000 includes the camera module provided by the embodiment of the present application. The camera module provided by the embodiment of the present application includes the image sensor provided by the embodiment of the present application. The image sensor provided by the embodiment of the present application includes the pixel circuit provided by the embodiment of the present application.

[0086] The processor 1010 is configured to: when it is required to enhance a high dynamic range of an image, acquire a voltage signal of a positive electrode of a photosensitive element in a pixel sub-unit of n rows and n columns; and generate a first image according to the voltage signal.

[0087] In the embodiments of the present application, the image is generated by the electrical signal of the positive electrode of the photosensitive element, a large dynamic range image can be generated, the high dynamic range of the image can be improved, and motion blur is not generated, effectively improving the image quality.

[0088] It should be understood that, in the embodiments of the present application, the input unit 1004 can include a graphics processing unit (GPU) 10041 and a microphone 10042. The graphics processing unit 10041 processes image data of a still picture or a video obtained by an image capture device (such as a camera) in a video capture mode or an image capture mode. The display unit 1006 can include a display panel 10061, which can be configured in the form of a liquid crystal display, an organic light-emitting diode, etc. The user input unit 1007 includes at least one of a touch panel 10071 and other input devices 10072. The touch panel 10071 is also called a touch screen. The touch panel 10071 can include two parts of a touch detection device and a touch controller. The other input devices 10072 can include, but are not limited to, a physical keyboard, function keys (such as volume control keys, on-off keys, etc.), a trackball, a mouse, an operating rod, and the like, which will not be described here.

[0089] The memory 1009 can be used to store software programs and various data. The memory 1009 can mainly include a first storage area storing programs or instructions and a second storage area storing data, wherein the first storage area can store an operating system, application programs or instructions required by at least one function (such as a sound playing function, an image playing function, etc.), and the like. In addition, the memory 1009 can include a volatile memory or a non-volatile memory, or the memory 1009 can include both volatile and non-volatile memories. The non-volatile memory can be a Read-Only Memory (ROM), a Programmable ROM (PROM), an Erasable PROM (EPROM), an Electrically EPROM (EEPROM), or a flash memory. The volatile memory can be a Random Access Memory (RAM), a Static RAM (SRAM), a Dynamic RAM (DRAM), a Synchronous DRAM (SDRAM), a Double Data Rate SDRAM (DDR SDRAM), an Enhanced SDRAM (ESDRAM), a Synch link DRAM (SLDRAM), and a Direct Rambus RAM (DRRAM). The memory 1009 in the embodiments of the present application includes but is not limited to these and any other suitable types of memories.

[0090] The processor 1010 can include one or more processing units; optionally, the processor 1010 integrates an application processor and a modem processor, wherein the application processor mainly processes operations related to an operating system, a user interface, and an application program, and the modem processor mainly processes wireless communication signals, such as a baseband processor. It can be understood that the above-mentioned modem processor can also not be integrated into the processor 1010.

[0091] The embodiments of the present application also provide a readable storage medium, the readable storage medium stores programs or instructions, the programs or instructions are executed by a processor to realize various processes of the above-mentioned image generation method embodiments, and the same technical effects can be achieved. To avoid repetition, details are not described here.

[0092] The processor is the processor in the electronic device described in the above embodiments. The readable storage medium includes a computer readable storage medium, examples of the computer readable storage medium include non-transitory computer readable media, such as computer readable only memory (ROM), random access memory (RAM), magnetic disk or optical disk, etc.

[0093] The embodiment of the present application further provides a chip, which comprises a processor and a communication interface, the communication interface is coupled with the processor, the processor is used for running programs or instructions to realize the processes of the above image generation method embodiment and achieve the same technical effects. To avoid repetition, details are not described here.

[0094] It should be understood that the chip mentioned in the embodiment of the present application can also be referred to as a system-level chip, a system chip, a chip system or a system-on-chip chip, etc.

[0095] The embodiment of the present application further provides a computer program product, which is stored in a storage medium, and is executed by at least one processor to realize the processes of the above image generation method embodiment and achieve the same technical effects. To avoid repetition, details are not described here.

[0096] It should be noted that in this document, the term "comprising" or "including" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements, but also includes other elements not explicitly listed or inherent to such a process, method, article or device. Without more limitations, the element defined by the statement "comprising a" does not exclude the presence of additional identical elements in the process, method, article or device including the element. In addition, it should be pointed out that the scope of the method and device in the present application is not limited to the order of performing the functions as shown or discussed, but can also include performing the functions in a substantially simultaneous manner or in the opposite order, for example, the described method can be performed in an order different from that described, and various steps can also be added, omitted or combined. In addition, the features described with reference to some examples can be combined in other examples.

[0097] Through the above description of the embodiments, those skilled in the art can clearly understand that the above-mentioned example methods can be realized by means of software and a necessary general hardware platform, and of course, can also be realized by hardware, but in many cases, the former is a better embodiment. Based on such understanding, the technical solutions of the present application can be embodied in the form of a computer software product in essence or in the form of a part that contributes to the prior art, which is stored in a storage medium (such as a ROM / RAM, a magnetic disk, or an optical disk) and includes a plurality of instructions for causing a terminal (which can be a mobile phone, a computer, a server, or a network device, etc.) to execute the methods described in the various embodiments of the present application.

[0098] The embodiments of the present application are described above in combination with the drawings, but the present application is not limited to the above-mentioned specific embodiments, and the above-mentioned specific embodiments are only illustrative and not restrictive. Those skilled in the art can make many forms under the inspiration of the present application without departing from the scope of the present application and the scope protected by the claims.

Claims

1. A pixel circuit, characterized in that: The pixel circuit includes: a plurality of rows and columns of pixel units and a plurality of signal readout units; The input ends of the plurality of signal readout units are electrically connected one by one to the plurality of rows of pixel units; The output ends of the plurality of signal readout units are electrically connected one by one to a plurality of analog-to-digital converters; the signal readout units are used to read out the voltage signals corresponding to each row of pixel units to the analog-to-digital converters; Each pixel unit includes a high dynamic range readout sub-unit and n rows and n columns of pixel sub-units, where n is a positive integer greater than or equal to 2, and the pixel sub-units included in the same pixel unit have the same color; The first end of the high dynamic range readout subunit is electrically connected to the positive electrode of the photosensitive element included in the pixel subunit; A second end of the high dynamic range readout subunit is electrically connected to the analog-to-digital converter, and the high dynamic range readout subunit is used to output a high dynamic range image.

2. The pixel circuit according to claim 1, wherein: The pixel subunit includes a first switch tube, a photosensitive element and a second switch tube; The cathode of the photosensitive element is electrically connected to the source of the first switching tube; The drain of the first switching tube is electrically connected to a signal readout unit corresponding to a pixel unit including the photosensitive element; The positive electrode of the photosensitive element is electrically connected to the drain electrode of the second switching tube; The source of the second switch tube is grounded.

3. The pixel circuit according to claim 1, wherein: The high dynamic range readout subunit includes: a third switch tube and a first capacitor; The drain of the third switch tube is electrically connected to the positive electrode of the photosensitive element of the pixel subunit; The source of the third switch is electrically connected to the first plate of the first capacitor; The second plate of the first capacitor is grounded.

4. The pixel circuit according to claim 3, wherein: The high dynamic range readout subunit further includes: a fourth switch tube; The drain of the fourth switch tube is connected to the power supply; The source of the fourth switch tube is electrically connected to the first plate of the first capacitor.

5. The pixel circuit according to claim 3, wherein: The high dynamic range readout subunit further includes: a first signal amplifier and a first row selector; The drain of the signal amplifier is connected to a power supply; The source of the signal amplifier is electrically connected to the drain of the row selector; The gate of the signal amplifier is electrically connected to the first plate of the first capacitor; The source of the row selector is electrically connected to the analog-to-digital converter.

6. The pixel circuit according to claim 1, wherein: The signal readout unit includes: a reset transistor, a parasitic capacitor, a second signal amplifier and a second row selector; The gate of the second signal amplifier is electrically connected to the negative electrode of the photosensitive element included in the pixel subunit, the first plate of the parasitic capacitor, and the source of the reset transistor respectively; The drain of the second signal amplifier and the drain of the reset transistor are both connected to a power supply; A source of the second signal amplifier is electrically connected to a drain of the second row selector; A source of the second row selector is electrically connected to the analog-to-digital converter.

7. An image sensor, characterized in that: The image sensor comprises the pixel circuit according to any one of claims 1 to 6.

8. A camera module, characterized in that: The camera module includes the image sensor according to claim 7.

9. An electronic device, characterized in that: The electronic device includes the camera module according to claim 8.

10. An image generation method, characterized in that: Applicable to the electronic device according to claim 9; the method comprising: When it is necessary to enhance the high dynamic range of the image, obtaining the voltage signal of the positive electrode of the photosensitive element in the pixel sub-unit of the n rows and n columns; A first image is generated according to the voltage signal.

11. The method according to claim 10, characterized in that The obtaining of the voltage signal of the positive electrode of the photosensitive element in the pixel sub-unit of n rows and n columns includes: Disconnecting the switch tube electrically connected to the positive electrode of the photosensitive element in the pixel sub-units of n rows and n columns; The voltage signal of the positive electrode of the photosensitive element in the n rows and n columns of the pixel subunit is transmitted to the analog-to-digital converter for reading through the high dynamic range readout subunit to obtain a voltage signal that combines the voltage signals of the positive electrode of the photosensitive element in the n rows and n columns of the pixel subunit.

12. The method according to claim 11, characterized in that The method further comprises: When the image clarity needs to be enhanced, the switch tube electrically connected to the negative electrode of the photosensitive element in the pixel sub-units of n rows and n columns is closed; The signal readout unit transmits the voltage signal of the negative electrode of the photosensitive element in each row of pixel units to the analog-to-digital converter for reading, thereby obtaining the voltage signal corresponding to each row of pixel units; A second image is generated according to the voltage signal corresponding to each row of pixel units.

Images