Photosensitive pixel for realizing time delay integral, image acquisition device and method

Abstract

The invention relates to the technical field of image sensing, in particular to a photosensitive pixel for realizing time delay integration, and an image acquisition device and method. According to the photosensitive pixel provided by the invention, due to the multi-sampling switched capacitor unit, a plurality of photosensitive pixels on a column slice of a pixel array can receive an image signal voltage and a reset signal voltage of a local sub-region after primary amplification in each sampling period; the multi-sampling switched capacitor unit is controlled to store the image signal voltage and the reset signal voltage after primary amplification, so that the photosensitive pixel reads the image signal voltage and the reset signal voltage after primary amplification of the same local sub-region from the multi-sampling switched capacitor unit in a reading operation period, and the second amplification unit is controlled to perform secondary amplification; and the second output end is used for outputting the image signal voltage and the reset signal voltage of the local sub-region after secondary amplification, so that time delay integration of the CMOS image sensor can be realized, the signal-to-noise ratio during image acquisition is enhanced, and the image quality is improved.

Description

Technical Field

[0001] The present application relates to the field of image sensing technology, and in particular to a photosensitive pixel, an image acquisition device and a method for realizing time delay integration. Background Art

[0002] Linear array image sensors use the relative motion of the image sensor to the object being photographed to capture the linear motion at different times. The imaging speed of the linear array image sensor needs to match the object's motion speed. When the object's motion speed increases, the sensor's exposure time becomes shorter, resulting in insufficient sensor sensitivity and signal-to-noise ratio. In order to solve the problem of low signal-to-noise ratio of linear array image sensors, time delay integration (TDI) technology came into being. It aims to use its special scanning method to perform multiple time-sharing exposures on the same target through multiple rows of pixels, and analyze and fuse the results of multiple time-sharing exposures to achieve a higher signal-to-noise ratio and sensitivity.

[0003] In the related art, the CCD type TDI image sensor can realize the TDI function by transferring charges between pixels according to the relative motion between the sensor and the photographed object. However, the application of TDI sensors is limited by the disadvantages of low integration and high power consumption. Therefore, how to realize the time delay integration of CMOS image sensors, enhance the signal-to-noise ratio during image acquisition and improve image quality has become a problem that needs to be solved urgently in the industry. Summary of the invention

[0004] The present application aims to solve at least one of the technical problems existing in the prior art. To this end, the present application proposes a photosensitive pixel, an image acquisition device and a method for realizing time delay integration, which can realize time delay integration of CMOS image sensors, enhance the signal-to-noise ratio during image acquisition and improve image quality.

[0005] According to the first aspect of the present application, a photosensitive pixel includes:

[0006] A photosensitive element, used for receiving an external light signal and converting the external light signal into an electrical signal of an image;

[0007] A global reset switch, the global reset switch is configured at the suspension node, and is used to control the voltage reset of the suspension node to provide a reset signal voltage;

[0008] a first amplifying unit, comprising a first receiving end, a first control end and a first output end, wherein the first receiving end is connected to the photosensitive element via a suspension node, and is used to receive an electrical signal of the photosensitive element via the suspension node to provide an image signal voltage, and the first control end is used to control the first amplifying unit to perform a first-stage amplification on the image signal voltage and the reset signal voltage of the suspension node; wherein the suspension node is grounded via a first capacitor;

[0009] A multi-sampling switch capacitor unit, comprising a sampling receiving end and a sampling output end, wherein the sampling receiving end is connected to the first output end and is used to receive the image signal voltage and reset signal voltage after the first stage of amplification, and the multi-sampling switch capacitor unit includes a first number of sampling signal sub-units and a second number of sampling reset sub-units between the sampling receiving end and the sampling output end; wherein the multi-sampling switch capacitor unit is used to store the image signal voltage and reset signal voltage after the first stage of amplification through the sampling signal sub-unit and the sampling reset sub-unit;

[0010] The second amplifying unit comprises a second receiving end, a second control end and a second output end; wherein the second receiving end is connected to the sampling output end and is used to read the image signal voltage and reset signal voltage after the first stage amplification from the multi-sampling switch capacitor unit, the second control end is used to control the voltage reset of the second receiving end, and the second output end is used to output the image signal voltage and reset signal voltage after the second stage amplification.

[0011] The photosensitive pixel according to the embodiment of the present application has at least the following beneficial effects:

[0012] The photosensitive pixel of the embodiment of the present application, thanks to the multi-sampling switch capacitor unit, can store the image signal voltage and reset signal voltage after the first stage of amplification through the sampling signal subunit and the sampling reset subunit after receiving the image signal voltage and reset signal voltage after the first stage of amplification. Then, the second amplification unit can selectively read the image signal voltage and reset signal voltage after the first stage of amplification collected by different pixels at different times on the same local sub-area from the multi-sampling switch capacitor unit, and output the image signal voltage and reset signal voltage after the second stage of amplification. In this way, it can help realize the time delay integration of the CMOS image sensor, enhance the signal-to-noise ratio during image acquisition, and improve image quality.

[0013] The photosensitive pixel of the embodiment of the present application has at least the following beneficial effects:

[0014] For a third number of rows of pixels in the pixel array, the multi-sampling switch capacitor unit of each pixel may include a first number of sampling signal subunits for storing image signal voltages of the pixel at a first number of time points, and a second number of sampling reset subunits for storing reset signal voltages of the pixel at a second number of time points.

[0015] If the first number and the second number are equal to the third number, the image signal voltage and the reset signal voltage of each pixel at each time point are stored, and double sampling can be achieved to reduce random noise and fixed pattern noise caused by offset voltage.

[0016] If the first number and the second number are equal and one more than the third number, the image signal voltage and reset signal voltage of each pixel are stored, double sampling can be achieved, and random noise and fixed pattern noise caused by offset voltage can be reduced. In addition, the one more sampling signal subunit and sampling reset subunit can support pipeline operations for signal sampling and reading, effectively improving the speed of the TDI sensor, that is, increasing the line frequency.

[0017] If the first number and the third number are equal and the second number is equal to one, each pixel can achieve double sampling to reduce the fixed pattern noise caused by the offset voltage. The second number equal to one can reduce the complexity of the pixel and improve the pixel sensitivity and signal-to-noise ratio.

[0018] If the first number is one more than the third number and the second number is equal to one, each pixel can achieve double sampling to reduce the fixed pattern noise caused by the offset voltage. The additional sampling signal subunit and sampling reset subunit can support pipeline operation and effectively increase the speed of the TDI sensor, that is, the line frequency. The second number equal to one can reduce the complexity of the pixel and improve the pixel sensitivity and signal-to-noise ratio.

[0019] According to some embodiments of the present application, the first amplification unit includes a first source follower and a current control switch;

[0020] The drain of the first source follower is used to connect to a first operating voltage;

[0021] The gate of the first source follower is connected to the photosensitive element via a suspension node as the first receiving end;

[0022] The source of the first source follower is connected to the drain of the current control switch, and the first output terminal is led out from the connection line between the first source follower and the current control switch and connected to the sampling receiving terminal;

[0023] The gate of the current control switch serves as the first control terminal for controlling the first amplifying unit to perform a first-stage amplification on the image signal voltage and the reset signal voltage, and the source of the current control switch is grounded.

[0024] According to some embodiments of the present application, inside the multi-sampling switch capacitor unit, a first number of the sampling signal subunits and a second number of the sampling reset subunits connected in parallel are provided between the sampling receiving end and the sampling output end;

[0025] The sampling signal subunit is provided with a first sampling switch and a first reading switch connected in series in sequence between the sampling receiving end and the sampling output end; wherein a branch is led out from the connection line between the first sampling switch and the first reading switch, connected to one end of the first sampling capacitor, and the other end of the first sampling capacitor is grounded;

[0026] The sampling reset subunit is provided with a second sampling switch and a second reading switch connected in series in sequence between the sampling receiving end and the sampling output end; wherein a branch is led out from the connection line between the second sampling switch and the second reading switch, connected to one end of the second sampling capacitor, and the other end of the second sampling capacitor is grounded;

[0027] The first sampling control interface of the first sampling switch configuration, the first reading control interface of the first reading switch configuration, the second sampling control interface of the second sampling switch configuration, and the second reading control interface of the second reading switch configuration serve as the storage control interface, and are used to control the multi-sampling switch capacitor unit to access and read the image signal voltage and reset signal voltage after the first stage of amplification.

[0028] The photosensitive pixel of the embodiment of the present application has at least the following beneficial effects: a first number of sampling signal sub-units and a second number of sampling reset sub-units connected in parallel are provided between the sampling receiving end and the sampling output end, and the parallel structure can effectively support pipeline operation and improve the line frequency of the sensor.

[0029] According to some embodiments of the present application, inside the multi-sampling switch capacitor unit, a first number of the signal sampling subunits connected in parallel are provided between the sampling receiving end and the sampling output end, and a second number of the sampling reset subunits are connected to the sampling output end;

[0030] The sampling signal subunit comprises a third sampling switch and a third reading switch which are sequentially connected in series at the sampling receiving end and the sampling output end; wherein a branch is led out from the connection line between the third sampling switch and the third reading switch, connected to one end of the third sampling capacitor, and the other end of the third sampling capacitor is grounded;

[0031] The sampling and resetting subunit has a branch extending from the sampling output end connected to the input end of the first sampling and reading switch, the output end of the first sampling and reading switch is connected to one end of the first sampling and reading capacitor, and the other end of the first sampling and reading capacitor is grounded;

[0032] The third sampling switch is configured with a third sampling control terminal, the third reading switch is configured with a third reading control terminal, and the first reading switch is configured with a first reading control terminal; wherein the third sampling control terminal, the third reading control terminal and the first reading control terminal serve as the storage control interface, and are used to control the multi-sampling switch capacitor unit to access the image signal voltage and reset signal voltage after the first stage of amplification.

[0033] The photosensitive pixel of the embodiment of the present application has at least the following beneficial effects: by simplifying the structure of the sampling and resetting subunit, the complexity of the pixel can be effectively reduced, the fill factor of the sensor can be increased, and the sensitivity can be improved.

[0034] According to some embodiments of the present application, the first amplification unit includes a first source follower;

[0035] The drain of the first source follower is used to connect to a second operating voltage;

[0036] The gate of the first source follower is connected to the photosensitive element via a suspension node as the first receiving end;

[0037] The source of the first source follower is connected to the sampling receiving end as the first output end.

[0038] The photosensitive pixel of the embodiment of the present application has at least the following beneficial effects: the drain of the first source follower is used to connect to the second operating voltage, and the amplification function of the first amplification unit can be realized without a current control switch, thereby simplifying the pixel structure, improving the fill factor of the sensor and improving sensitivity.

[0039] According to some embodiments of the present application, a first sampling circuit is provided inside the multi-sampling switch capacitor unit between the sampling receiving end and the sampling output end, a global sampling switch is provided in the first sampling circuit, an input end of the global sampling switch is connected to the sampling receiving end, and an output end of the global sampling switch is connected to the sampling output end;

[0040] Inside the multi-sampling switch capacitor unit, a first number of sampling signal subunits and a second number of sampling reset subunits are provided between the sampling receiving end and the sampling output end;

[0041] A first number of the sampling signal subunits are connected to the connection line between the output end of the global sampling switch and the sampling output end through a first side branch port; wherein each of the sampling signal subunits includes a second sampling branch connected to the first side branch port;

[0042] A second number of the sampling and resetting subunits are connected to the connection line between the first side branch port and the sampling output terminal through a second side branch port; wherein each of the sampling and resetting subunits includes a third sampling and reading branch connected to the second side branch port;

[0043] The second acquisition and reading branch is connected in series with a second acquisition and reading switch and a second acquisition and reading capacitor in sequence between the first side branch port and the ground; wherein the second acquisition and reading switch is configured with a second acquisition and reading control interface;

[0044] The third reading branch has a third reading switch and a third reading capacitor connected in series in sequence between the second side branch port and the ground; wherein the third reading switch is configured with a third reading control interface;

[0045] The control end of the global sampling switch, the second sampling control interface and the third sampling control interface serve as the storage control interface, and are used to control the multi-sampling switch capacitor unit to access the image signal voltage and reset signal voltage after the first stage of amplification.

[0046] The photosensitive pixel of the embodiment of the present application has at least the following beneficial effects: by introducing a global sampling switch, the structure of the sampling signal subunit can be further simplified on the basis of simplifying the structure of the sampling reset subunit, thereby continuing to reduce the complexity of the pixel, and improving the fill factor of the sensor and improving sensitivity.

[0047] According to some embodiments of the present application, the second amplification unit includes a second source follower and a readout reset switch;

[0048] The drain of the second source follower is used to connect to a third operating voltage;

[0049] The gate of the second source follower is connected to the sampling output end as the second receiving end, and is used to read the image signal voltage and reset signal voltage after the first stage of amplification from the multi-sampling switch capacitor unit;

[0050] The drain of the readout reset switch is used to connect to a reference voltage;

[0051] The gate of the readout reset switch serves as the second control terminal, and is used to reset the connection line between the sampling second receiving terminal and the sampling output terminal;

[0052] The source of the readout reset switch is connected to the connection line between the second receiving end and the sampling output end;

[0053] The source of the second source follower serves as the second output terminal, and is used to output the image signal voltage and reset signal voltage after secondary amplification.

[0054] According to some embodiments of the present application, a transmission switch is provided between the photosensitive element and the suspension node, and the transmission switch is used to control the transmission of the image electrical signal collected by the photosensitive element to the suspension node to form an image signal voltage.

[0055] The photosensitive pixel of the embodiment of the present application has at least the following beneficial effects: the transmission switch is used to implement the correlated double sampling operation of the reset voltage and the signal voltage, effectively reducing the fixed deviation caused by random noise and offset voltage.

[0056] According to the second aspect of the present application, the image acquisition device includes: a photosensitive module generated based on the photosensitive pixels described in any one of the first aspect of the present application.

[0057] According to some embodiments of the present application, the photosensitive module includes a plurality of photosensitive pixels; wherein the plurality of photosensitive pixels are arranged in rows and columns in the photosensitive module of the image acquisition device to form a pixel array;

[0058] On each column slice in the pixel array, each row of photosensitive pixels corresponds to a local sub-region, and signal acquisition is performed on a local region of the target object composed of multiple local sub-regions at multiple time points within the target time interval. The column signal line output by each photosensitive pixel is used to output the image signal voltage and reset signal voltage of the local sub-region after secondary amplification acquired by each pixel at different time points for the same local sub-region. The target integrated signal is obtained by fusing the image signal voltage and reset signal voltage after secondary amplification output by multiple column signal lines.

[0059] According to some embodiments of the present application, in the pixel array, the output column signal lines of each photosensitive pixel corresponding to each column slice are connected to form a column bus; wherein each row of photosensitive pixels corresponds to a local sub-region, and signal acquisition is performed on a local region of the target object composed of multiple local sub-regions at multiple time points within a target time interval, and the output column signal line is used to output the secondary amplified image signal voltage and reset signal voltage acquired by each of the photosensitive pixels on the same local sub-region at different time points, and the column bus is used to transmit and fuse the secondary amplified image signal voltage and reset signal voltage output by multiple column signal lines.

[0060] The output column signal lines of each of the photosensitive pixels are connected to form a column bus, which has at least the following beneficial effects: the image signal voltages collected by each row of photosensitive pixels for the same local sub-area at different time points are close, and direct voltage averaging can be achieved by short-circuiting to the column bus, thereby quickly and effectively completing signal superposition and achieving a high signal-to-noise ratio effect.

[0061] According to some embodiments of the present application, the layout arrangement of the photosensitive pixels in the photosensitive module includes a matrix layout or a distributed layout.

[0062] The distributed layout has at least the following beneficial effects: when pixel space is limited, part of the circuit is implemented in the column readout circuit to facilitate achieving a higher pixel fill factor and obtaining a higher sensitivity.

[0063] According to the image acquisition method of the third aspect of the present application, applied to the image acquisition device of the second aspect of the present application, the method includes:

[0064] The photosensitive pixels are arranged in rows and columns to form a pixel array, wherein the photosensitive pixels of a column slice have multiple rows, and each row of pixels corresponds to a local sub-region. Signals are collected from a local region of a target object consisting of multiple local sub-regions at multiple time points within a target time interval to obtain corresponding groups of primary amplified image signal voltages and reset signal voltages of the local regions; wherein the primary amplified image signal voltages and reset signal voltages of each group of the local regions include the primary amplified image signal voltages and reset signal voltages of the local sub-region collected by the multi-sampling switch capacitor units of the photosensitive pixels of each row at a time point within the target time interval for each of the local sub-regions;

[0065] Performing secondary amplification and signal analysis fusion processing on the primary-amplified image signal voltages and reset signal voltages of the plurality of local regions respectively, to obtain fused local sub-region image signal voltages and reset signal voltages corresponding to each of the local sub-regions;

[0066] Determine a time-integrated local sub-region image based on the fused local sub-region image signal voltage and the reset signal voltage;

[0067] The multiple time-integrated local sub-region images are integrated and spliced ​​to obtain a time-integrated target acquisition image of the target object.

[0068] The image acquisition device and the image acquisition method according to the embodiments of the present application have at least the following beneficial effects:

[0069] By using the relative displacement between the pixel and the photographed object, through the multi-sampling switch capacitor unit, it is helpful for each row of pixels to sample a local area of ​​the photographed object composed of multiple local sub-areas at different times during the sampling operation stage. In the reading operation stage, the image signal voltage and reset signal voltage at the same position at different times of the corresponding sampling sub-units of each row are read by cyclic selection. The image signal voltage and reset signal voltage of each local sub-area are obtained by multiple sampling, and then the time-integrated image is obtained after signal fusion, achieving the beneficial effect of enhancing the signal-to-noise ratio.

[0070] According to some embodiments of the present application, the signal acquisition is performed on a local area of ​​the target object consisting of multiple local sub-areas at multiple time points within the target time interval to obtain the first-level amplified image signal voltage and reset signal voltage of the corresponding multiple groups of local areas, including:

[0071] Based on a column slice of the photosensitive pixel array, multiple rows of photosensitive pixels perform signal acquisition for a local area of ​​the target object composed of multiple local sub-areas, and respectively obtain the local sub-area image signal voltage and reset signal voltage corresponding to one of the local sub-areas. Then, the relative positions of the multiple rows of photosensitive pixels and the target object are adjusted, and multiple rows of photosensitive pixels perform signal acquisition for another local area of ​​the target object composed of multiple local sub-areas, and respectively obtain the local sub-area image signal voltage and reset signal voltage corresponding to the other local sub-area, until the multiple rows of photosensitive pixels in a column slice complete the image signal voltage and reset signal voltage acquisition for one local sub-area of ​​the local area, and the multiple rows of photosensitive pixels obtain the image signal voltage and reset signal voltage of multiple groups of local areas, wherein each photosensitive pixel obtains the image signal voltage and reset signal voltage of the local sub-area corresponding to a time point of the local sub-area.

[0072] According to some embodiments of the present application, the multiple rows of photosensitive pixels of a column slice of a pixel array, the image signal voltage and reset signal voltage after the primary amplification of the multiple groups of local areas are subjected to secondary amplification and image signal analysis and fusion processing to obtain the fused local sub-area image signal voltage and reset signal voltage corresponding to each local sub-area, and the time-integrated local sub-area image can be obtained by the fused local sub-area image signal voltage and reset signal voltage, including:

[0073] Determine the first-stage amplified image signal voltage and reset signal voltage of the local sub-region collected by each of the photosensitive pixels for the same local sub-region from the first-stage amplified image signal voltage and reset signal voltage of each group of the local regions;

[0074] Based on the first-stage amplified image signal voltage and reset signal voltage of the local sub-region collected by each row of pixels of the same local sub-region, signal fusion processing is performed to obtain the fused local sub-region image signal voltage and reset signal voltage corresponding to the local sub-region, and the time-integrated local sub-region image can be obtained through the difference between the fused local sub-region image signal voltage and the reset signal voltage through an analog-to-digital converter;

[0075] After determining the time-integrated local sub-region image based on the fused local sub-region image signal voltage and the reset signal voltage, the method further includes:

[0076] The time-integrated local sub-region images are integrated and spliced ​​to obtain a target acquisition image corresponding to the time-integrated target object.

[0077] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0078] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0079] Figure 1 A schematic diagram of the circuit structure of a photosensitive pixel provided in an embodiment of the present application;

[0080] Figure 2 Another schematic diagram of the circuit structure of the photosensitive pixel provided in the embodiment of the present application;

[0081] FIG. 3A to FIG. 3B Another schematic diagram of the circuit structure of the photosensitive pixel provided in the embodiment of the present application;

[0082] Figure 3C A circuit timing diagram of a photosensitive pixel provided in an embodiment of the present application;

[0083] Figure 3D A timing diagram of the time delay integration operation of a photosensitive pixel provided in an embodiment of the present application;

[0084] FIG. 4A to FIG. 4B Another schematic diagram of the circuit structure of the photosensitive pixel provided in the embodiment of the present application;

[0085] Figure 4C A circuit timing diagram of a photosensitive pixel provided in an embodiment of the present application;

[0086] Figure 4D A timing diagram of the time delay integration operation of a photosensitive pixel provided in an embodiment of the present application;

[0087] FIG. 5A to FIG. 5B Another schematic diagram of the circuit structure of the photosensitive pixel provided in the embodiment of the present application;

[0088] Figure 5C A circuit timing diagram of a photosensitive pixel provided in an embodiment of the present application;

[0089] Figure 5D A timing diagram of the time delay integration operation of a photosensitive pixel provided in an embodiment of the present application;

[0090] Figure 6 Another schematic diagram of the circuit structure of the photosensitive pixel provided in the embodiment of the present application;

[0091] Figure 7 It is a flowchart of the image acquisition method provided in the embodiment of the present application; DETAILED DESCRIPTION

[0092] The embodiments of the present application are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present application, and cannot be understood as limiting the present application.

[0093] In the description of this application, "several" means one or more, "more" means more than two, "greater than", "less than", "exceed", etc. are understood to exclude the number itself, and "above", "below", "within", etc. are understood to include the number itself. If there is a description of "first" or "second", it is only used for the purpose of distinguishing technical features, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features or implicitly indicating the order of the indicated technical features.

[0094] In the description of the present application, it should be understood that descriptions involving orientation, such as up, down, left, right, front, back, etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0095] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0096] In the description of this application, it should be noted that, unless otherwise clearly defined, the terms such as setting, installing, connecting, etc. should be understood in a broad sense, and technicians in the relevant technical field can reasonably determine the specific meanings of the above terms in this application in combination with the specific content of the technical solution. In addition, the identification of specific steps below does not represent a limitation on the order of steps and execution logic. The execution order and execution logic between each step should be understood and inferred with reference to the contents described in the embodiment.

[0097] Image sensors can convert light signals obtained by the lens into electrical signals that are easy to store, transmit and process. Image sensors can be divided into area array type and line array type according to their working mode.

[0098] The working principle of the area array image sensor is to obtain two-dimensional image information by photographing an object with a pixel array arranged in a two-dimensional area array, while the working principle of the line array image sensor is to obtain two-dimensional image information by scanning and photographing an object with a pixel array arranged in a one-dimensional linear array;

[0099] Linear array image sensors are widely used in many fields such as machine vision and medical imaging due to their special working mode. Linear array image sensors use the relative movement of the image sensor to the object to be photographed, and take linear images at different times. The imaging speed of the linear array image sensor needs to match the object's movement speed. When the object's movement speed increases, the sensor's exposure time becomes shorter, resulting in insufficient sensor sensitivity and signal-to-noise ratio.

[0100] In the related art, in order to solve the problem of low signal-to-noise ratio of linear array image sensors, a time delay integration technology (TDI) is proposed. The purpose is to achieve a higher signal-to-noise ratio and sensitivity by exposing the same target multiple times through its special scanning method. Therefore, time delay integration is more suitable for high-speed motion and low-light environments, thereby increasing the signal-to-noise ratio and sensitivity of linear array image sensors.

[0101] The working principle of the time delay integration technology is to expose a local sub-area of ​​the photographed object to each row of pixels of a column slice of a linear array sensor with multiple rows of pixels, and the collected image signal voltage and reset signal voltage are divided into multiple rows and recorded row by row. In each row cycle, each row of pixels of the image sensor will record and store the image signal voltage and reset signal voltage of the local sub-area corresponding to each row. Then, in the next row cycle, the sensor has a relative movement to the photographed object, and each row of pixels of the image sensor will record and store the image signal voltage and reset signal voltage of another local sub-area corresponding to each row, until all rows of pixels complete the collection and storage of the image signal voltage and reset signal voltage of a local sub-area of ​​the photographed object, and the time-integrated image of the local sub-area can be obtained through the above multiple sets of image signal voltages and reset signal voltages. For each row cycle, the recording time of each row will be delayed a little, which is called "time delay integration". By delaying the recording time of each row, the time delay integration sensor can record and integrate the light signal multiple times when the image sensor moves. Therefore, in high-speed motion and low-light environments, the time-delayed integration sensor can use multiple integrations to enhance the signal-to-noise ratio of the image and improve the image quality. For this reason, the time-delayed integration sensor can be used in some applications that require high sensitivity and low noise, such as industrial detection and medical imaging. It can provide clearer and more accurate images in low-light conditions, making observation and analysis in low-light environments more feasible and effective.

[0102] In the related technology, the CCD type TDI image sensor can realize the TDI function by transferring charges between pixels according to the relative movement between the sensor and the photographed object. However, the application of TDI sensors is limited by the disadvantages of low integration and high power consumption. Therefore, how to realize the time delay integration of CMOS image sensors, enhance the signal-to-noise ratio during image acquisition and improve image quality has become a problem that needs to be solved urgently in the industry.

[0103] The present application aims to solve at least one of the technical problems existing in the prior art. To this end, the present application proposes a photosensitive pixel, an image acquisition device and a method for realizing time delay integration, which can realize time delay integration of CMOS image sensors, enhance the signal-to-noise ratio during image acquisition and improve image quality.

[0104] Reference Figure 1 According to the first aspect of the present application, the photosensitive pixel includes:

[0105] The photosensitive element 110 is used to receive external light signals and convert the external light signals into electrical signals of images.

[0106] It should be noted that the photosensitive pixel is a photosensitive unit of the image acquisition device, and the photosensitive pixel array is arranged together to form a photosensitive area of ​​the image acquisition device. The photosensitive element 110 in the embodiment of the present application is a component inside the photosensitive pixel that is specifically used to receive external light signals and convert the external light signals into image electrical signals.

[0107] The first amplifying unit 130 includes a first receiving terminal 131, a first control terminal 132 and a first output terminal 133; wherein the first receiving terminal 131 is connected to the photosensitive element 110 via the suspension node 120, and is used to receive the image signal voltage through the suspension node 120. The suspension node 120 is grounded through the first capacitor 121 and is configured with a global reset switch 122. The global reset switch 122 is configured at the suspension node 120, and is used to control the voltage reset of the suspension node 120 to provide a reset signal voltage. The first control terminal 132 is used to control the first amplifying unit 130 to perform a first-stage amplification on the image signal voltage and the reset signal voltage.

[0108] It should be noted that the first receiving end 131 of the first amplifying unit 130 is used to receive the image signal voltage and the reset signal voltage through the suspension node 120. The first amplifying unit 130 performs a first-stage amplification on the image signal voltage and the reset signal voltage under the control signal received at the first control end 132, and then outputs the first-stage amplified image signal voltage and reset signal voltage from the first output end 133.

[0109] The multi-sampling switch capacitor unit 140 includes a sampling receiving end 141 and a sampling output end 142. The sampling receiving end 141 is connected to the first output end 133 and is used to receive the image signal voltage and reset signal voltage after the first stage of amplification. The multi-sampling switch capacitor unit 140 includes a plurality of sampling sub-units between the sampling receiving end 141 and the sampling output end 142. Each sampling sub-unit is configured with a plurality of storage control interfaces, and the storage control interfaces are used to control the multi-sampling switch capacitor unit 140 to store the image signal voltage and reset signal voltage after the first stage of amplification. It should be noted that the sampling sub-units between the sampling receiving end and the sampling output end of the multi-sampling switch capacitor unit 140 may specifically include a first number of sampling signal sub-units and a second number of sampling reset sub-units; wherein the multi-sampling switch capacitor unit is used to store the image signal voltage and reset signal voltage after the first stage of amplification through the sampling signal sub-unit and the sampling reset sub-unit.

[0110] It should be noted that the multi-sampling switch capacitor unit 140 receives the image signal voltage and reset signal voltage after the first stage of amplification through the sampling receiving terminal 141, and uses the internal multi-sampling switch capacitor unit 140 to store the image signal voltage and reset signal voltage after the first stage of amplification under the control signal received by the storage control interface of each sampling sub-unit.

[0111] The second amplifying unit 150 includes a second receiving terminal 151, a second control terminal 152 and a second output terminal 153; wherein the second receiving terminal 151 is connected to the sampling output terminal 142, and is used to read the image signal voltage and reset signal voltage after the first stage amplification from the multi-sampling switch capacitor unit 140, the second control terminal 152 is used to reset the connection line between the sampling second receiving terminal 151 and the sampling output terminal 142, and the second output terminal 153 is used to output the image signal voltage and reset signal voltage after the second stage amplification.

[0112] It should be noted that, under the control signal received by the second control terminal 152, the second amplifier unit 150 can use the second receiving terminal 151 to read the image signal voltage and reset signal voltage after the first stage amplification from the multi-sampling switch capacitor unit 140, and then output the image signal voltage and reset signal voltage after the second stage amplification from the second output terminal 153. It should be understood that the photosensitive pixel is a photosensitive unit of the image acquisition device, and the photosensitive pixel array is arranged together to form a photosensitive area of ​​the image acquisition device, and the second output terminal 153 of the second amplifier unit 150 can be connected to other pixels through a column signal line. At this time, in order to actively output the image signal voltage and reset signal voltage, it is necessary to first perform a second stage amplification on the image signal voltage and reset signal voltage to obtain the image signal voltage and reset signal voltage after the second stage amplification, and then output the image signal voltage and reset signal voltage after the second stage amplification from the second output terminal 153.

[0113] According to the photosensitive pixel provided in the embodiment of the present application, thanks to the multi-sampling switch capacitor unit 140, after receiving the image signal voltage and reset signal voltage after the first stage of amplification, the image signal voltage and reset signal voltage after the first stage of amplification can be stored through the sampling signal subunit and the sampling reset subunit. Then, the second amplification unit can be used to read the image signal voltage and reset signal voltage after the first stage of amplification from the multi-sampling switch capacitor unit 140, and the image signal voltage and reset signal voltage after the second stage of amplification can be output. In this way, through the analytical fusion of the image signal voltage and reset signal voltage between pixels, it can help realize the time delay integration of the CMOS image sensor, enhance the signal-to-noise ratio during image acquisition, and improve the image quality.

[0114] According to the image acquisition device and image acquisition method of the embodiment of the present application, the photosensitive module includes a plurality of photosensitive pixels; wherein the plurality of photosensitive pixels are arranged in rows and columns in the photosensitive module of the image acquisition device to form a pixel array. On each column slice in the pixel array, the column signal line output by each photosensitive pixel is used to output the image signal voltage and reset signal voltage after the secondary amplification of each pixel. The image signal voltage and reset signal voltage are collected for the target object multiple times at multiple time points within the target time interval to obtain multiple corresponding groups of image signal voltages and reset signal voltages; wherein each group of image signal voltages and reset signal voltages includes the image signal voltage and reset signal voltage collected for a local area of ​​the target object composed of multiple local sub-areas at a time point within the target time interval. Further, image analysis and fusion processing are performed for each group of image signal voltages and reset signal voltages respectively to obtain the fused image signal voltage and reset signal voltage corresponding to each local sub-area, and the time-integrated local sub-area image can be obtained by the difference between the fused local sub-area image signal voltage and the reset signal voltage through the analog-to-digital converter, and the time-integrated local sub-area image is integrated to obtain the time-integrated target acquisition image of the target object. In this way, through the multiple capacitor storage inside the multi-sampling switch capacitor unit 140, it is helpful for each row of pixels to sample and store the photographed object in the sampling operation stage of multiple row cycles, and then select the sampling switch capacitor unit 140 of each row of pixels to read the signal voltage of the same local sub-area at different times in the reading operation stage.

[0115] Reference Figure 2 , according to some embodiments of the present application, the first amplifying unit 130 includes a first source follower 134 and a current control switch 135;

[0116] Based on this, in the embodiment of the present application, the drain of the first source follower 134 is used to connect to the first working voltage;

[0117] The gate of the first source follower 134 is connected to the photosensitive element 110 via the floating node 120 as the first receiving terminal 131;

[0118] The source of the first source follower 134 is connected to the drain of the current control switch 135 , and the first output terminal 133 is led out from the connection line between the first source follower 134 and the current control switch 135 and connected to the sampling receiving terminal 141 ;

[0119] The gate of the current control switch 135 serves as the first control terminal 132 for controlling the first amplification unit 130 to perform a first-stage amplification on the image signal voltage and the reset signal voltage, and the source of the current control switch 135 is grounded.

[0120] In this way, the gate of the current control switch 135 can be used as the first control terminal 132 to control the first amplification function of the first amplification unit 130 as a whole.

[0121] Reference Figure 3A According to some embodiments of the present application, inside the multi-sampling switch capacitor unit 140, a first number (e.g., 5 or other numbers) of sampling signal subunits 1430 and a second number (e.g., 5 or other numbers) of sampling reset subunits 1440 connected in parallel are provided between the sampling receiving terminal 141 and the sampling output terminal 142. Among them, one sampling signal subunit 1430 and one sampling reset subunit 1440 can constitute one double sampling subunit;

[0122] The sampling signal subunit 1430 is provided with a first sampling switch 1431 and a first reading switch 1432 connected in series in sequence between the sampling receiving terminal 141 and the sampling output terminal 142; wherein a branch is led out from the connection line between the first sampling switch 1431 and the first reading switch 1432, connected to one end of the first sampling capacitor 1433, and the other end of the first sampling capacitor 1433 is grounded;

[0123] The sampling reset subunit 1440 is provided with a second sampling switch 1441 and a second reading switch 1442 connected in series in sequence between the sampling receiving terminal 141 and the sampling output terminal 142; wherein a branch is led out from the connection line between the second sampling switch 1441 and the second reading switch 1442, connected to one end of the second sampling capacitor 1443, and the other end of the second sampling capacitor 1443 is grounded;

[0124] The first sampling control interface configured by the first sampling switch 1431, the first reading control interface configured by the first reading switch 1432, the second sampling control interface configured by the second sampling switch 1441, and the second reading control interface configured by the second reading switch 1442 are used as storage control interfaces to control the multi-sampling switch capacitor unit 140 to access the image signal voltage and reset signal voltage after the first stage of amplification.

[0125] It should be noted that, based on the on / off state changes of the first sampling control interface and the second sampling control interface, the image signal voltage after the first stage of amplification can be stored in the first sampling capacitor 1433, or the reset signal voltage after the first stage of amplification can be stored in the second sampling capacitor 1443. Further, based on the on / off state changes of the first reading control interface and the second reading control interface, the image signal voltage after the first stage of amplification can be read from the first sampling capacitor 1433, or the reset signal voltage after the first stage of amplification can be read from the second sampling capacitor. In this way, the sampling or reading of the image signal voltage and the reset signal voltage can be achieved.

[0126] Reference Figure 3B According to some embodiments of the present application, a transmission switch is provided between the photosensitive element 110 and the first amplifying unit 130, and the transmission switch is used to control the image electrical signal collected from the photosensitive element 110 to be transmitted to the suspension node 120 to become an image signal voltage.

[0127] According to some more specific embodiments of the present application. Figure 3B As shown, the control signals of each component in the photosensitive pixel are as follows:

[0128] The global reset switch 122 is controlled by a control signal GRST;

[0129] The first control terminal 132 of the first amplifying unit 130 is controlled by a control signal PC;

[0130] The transmission switch is controlled by the control signal TX;

[0131] The second control terminal 152 of the second amplifying unit 150 is controlled by a control signal RRST;

[0132] The first sampling control interfaces of the five sampling signal subunits are respectively controlled by five control signals SSN (N=1 / 2 / 3 / 4 / 5);

[0133] The second sampling control interfaces of the five sampling reset subunits are respectively controlled by five control signals SRN (N=1 / 2 / 3 / 4 / 5);

[0134] The first read control interfaces of the five sampling signal subunits are respectively controlled by five control signals RSN (N=1 / 2 / 3 / 4 / 5);

[0135] The second read control interfaces of the five sampling and resetting subunits are respectively controlled by five control signals RRN (N=1 / 2 / 3 / 4 / 5).

[0136] Reference Figure 3C , some more specific embodiments are shown with reference to Figure 3BCircuit timing diagram of a single pixel in the figure. Each photosensitive pixel is configured with a multi-sampling switch capacitor unit 140, and five double sampling sub-units are arranged in parallel between the sampling receiving terminal 141 and the sampling output terminal 142 in the multi-sampling switch capacitor unit 140, and each double sampling sub-unit is arranged in parallel with one sampling signal sub-unit and one sampling reset sub-unit. Specifically, in each row cycle, the operation of the photosensitive pixel is divided into a sampling operation and a reading operation, and the sampling operation and the reading operation can be processed in parallel, that is, a pipeline operation, wherein one double sampling sub-unit performs a sampling operation of the image signal voltage and reset signal voltage after the first stage of amplification collected by the photosensitive pixel, and one double sampling sub-unit performs a reading operation of the image signal voltage and reset signal voltage after the first stage of amplification collected by the photosensitive pixel, and the double sampling sub-unit that does not participate in the sampling operation and the reading operation maintains the storage of the image signal voltage and the reset signal voltage after the first stage of amplification. The following is about Figure 3C The circuit timing diagram is shown for explanation:

[0137] When the photosensitive pixel is used to perform the sampling operation stage, a group of first sampling switches, second sampling switches, first reading switches, and second reading switches are controlled to be turned on and off by a group of control signals SRN, SSN, RRN, and RSN, and a double sampling sub-unit performs sampling of the image signal voltage and reset signal voltage after the first stage of amplification; a double sampling sub-unit performs the reading of the image signal voltage and reset signal voltage after the first stage of amplification to the column signal line through the second amplification unit through the conduction and shutdown of a group of control signals SRN, SSN, RRN, and RSN; 12 control signals SRN, SSN, RRN, and RSN of the three double sampling sub-units are low to maintain the storage of the sampled image signal voltage and reset signal voltage after the first stage of amplification: the control signal GRST is pulled high to turn on the global reset switch, and the suspended node of the photosensitive pixel Point 120 is reset to become a reset signal voltage, the control signal GRST is pulled low to turn off the global reset switch, the control signal PC is pulled high to turn on the first control switch and enter the sampling state, the control signal SRN is pulled high and then low, the second sampling switch is turned on and then off, and the reset signal voltage after the first stage amplification is sampled to the second sampling capacitor 1443, the control signal TX is pulled high and then low to control the on and off of the transmission switch, and the image electrical signal charge of the photosensitive element 110 is transferred to the suspension node 120 to become the image signal voltage, the control signal SSN is pulled high and then low, the first sampling switch is turned on and then off, and the image signal voltage after the first stage amplification is sampled to the first sampling capacitor 1433, and then the control signal PC is pulled low again to turn off the first control switch, and the control signal GRST is pulled high to turn on the global reset switch and end the sampling.

[0138] When the photosensitive pixel is used to perform a reading operation, a group of first sampling switches, second sampling switches, first reading switches, and second reading switches are turned on and off by a group of control signals SRN, SSN, RRN, and RSN, and a double sampling subunit performs sampling of the image signal voltage and reset signal voltage after the first stage of amplification; a double sampling subunit performs the reading of the image signal voltage and reset signal voltage after the first stage of amplification to the column signal line through the second amplifier unit through the turn-on and turn-off of a group of control signals SRN, SSN, RRN, and RSN; 12 control signals of the three double sampling subunits are used to control the image signal voltage and reset signal voltage after the first stage of amplification. Signals SRN, SSN, RRN, and RSN are low to maintain the storage of the image signal voltage and the reset signal voltage after the first stage of amplification: pull up and then pull down the control signal RRST to control the second control end to clear the level of the sampling output end 142, pull up and then pull down a control signal RRN to read the reset signal voltage after the first stage of amplification, perform secondary amplification, and then output it to the column signal line, pull up and then pull down the control signal RRST to control the second control end to clear the level of the sampling output end 142 again, pull up and then pull down a control signal RSN to read the image signal voltage after the first stage of amplification, perform secondary amplification, and then output it to the column signal line.

[0139] based on Figure 3C The circuit timing diagram of the embodiment is shown, and the control signals of each component in the photosensitive pixel are manipulated, so that the sampling operation and the reading operation of the image signal voltage and the reset signal voltage can be implemented in parallel within one line cycle. The image signal voltage and the reset signal voltage after the first stage of amplification are stored in the double sampling subunit (i.e., the sampling operation), and the image signal voltage and the reset signal voltage after the first stage of amplification are read out from the double sampling subunit and output after the second stage of amplification (i.e., the reading operation).

[0140] It should be understood that Figure 3C The circuit timing diagram shown is an example of controlling a photosensitive pixel. The embodiments of the present application may include, but are not limited to: Figure 3C The control process of the photosensitive pixel is shown.

[0141] When the image acquisition device provided in the embodiment of the present application includes Figure 3B The photosensitive pixels shown can be Figure 3D The illustrated embodiment performs a time delay integration (TDI) operation to capture an image of a target object. The operation timing of each photosensitive pixel can refer to Figure 3C The operation timing is shown. Specifically:

[0142] The photosensitive pixels can be presented in a matrix form in the image acquisition device. For example, a column of pixels includes 4 rows of photosensitive pixels, and the photosensitive pixels in the first row to the fourth row are represented as PIX1, PIX2, PIX3, and PIX4 respectively. The multi-sampling switch capacitor unit 140 of each pixel has 5 double sampling sub-units, and the 5 double sampling sub-units of PIX1 for storing the image signal voltage and reset signal voltage after the first stage of amplification are abbreviated as C_01 / 02 / 03 / 04 / 05, respectively, the 5 double sampling sub-units of PIX2 for storing the image signal voltage and reset signal voltage after the first stage of amplification are abbreviated as C_06 / 07 / 08 / 09 / 10, respectively, the 5 double sampling sub-units of PIX3 for storing the image signal voltage and reset signal voltage after the first stage of amplification are abbreviated as C_11 / 12 / 13 / 14 / 15, respectively, and the 5 double sampling sub-units of PIX4 for storing the image signal voltage and reset signal voltage after the first stage of amplification are abbreviated as C_16 / 17 / 18 / 19 / 20. The image signal voltage and reset signal voltage after first-stage amplification of the same local sub-area captured in multiple double sampling sub-units at different times stored in PIX1, PIX2, PIX3, and PIX4 are sent to the respective column signal lines through the respective second amplification units 150.

[0143] Figure 3D In a column slice, each row time, the photosensitive pixels P IX1, P IX2, P IX3, and P IX4 respectively capture a color rectangle (such as A, B, C, D, E, F, G, H), that is, a local sub-region of the target object, and obtain the local sub-region image signal voltage and reset signal voltage. The 4 local sub-regions captured by 4 pixels constitute a local region, and the obtained signals are the local image signal voltage and reset signal voltage.

[0144] 4 photosensitive pixels PIX1, PIX2, PIX3, PIX4.

[0145] The corresponding relationship of signal sampling of local sub-areas A, B, C, D, E, F, G, H, and N by PIX1 is abbreviated as P1_A, P1_B, P1_C, P1_D, P1_E, P1_F, P1_G, P1_H, P1_N,

[0146] The corresponding relationship of signal sampling of local sub-areas A, B, C, D, E, F, G, H, and N by PIX2 is abbreviated as P2_A, P2_B, P2_C, P2_D, P2_E, P2_F, P2_G, P2_H, P2_N,

[0147] The corresponding relationship of signal sampling of local sub-areas A, B, C, D, E, F, G, H, and N by PIX3 is abbreviated as P3_A, P3_B, P3_C, P3_D, P3_E, P3_F, P3_G, P3_H, P3_N,

[0148] The corresponding relationship between PIX4's signal sampling of local sub-areas A, B, C, D, E, F, G, H, and N is abbreviated as P4_A, P4_B, P4_C, P4_D, P4_E, P4_F, P4_G, P4_H, and P4_N.

[0149] Reference Figure 3D The sampling and reading method of the four rows of photosensitive pixels in the image acquisition device and the TDI stacking operation timing can be as follows: Figure 3D As shown. Among them, TN-4, TN-3, TN-2, TN-1, TN, TN+1, TN+2, TN+3, respectively refer to different row periods. In each row period, the four pixels PIX1, PIX2, PIX3, PIX4 on the column slice respectively collect the image signal voltage and reset signal voltage of the target object, wherein each pixel corresponds to a local sub-region to collect the image signal voltage and reset signal voltage of the local sub-region, and store them in a double sampling sub-unit through their respective first amplification units 130.

[0150] In the row cycle TN-4, PIX1, PIX2, PIX3, and PIX4 respectively collect local sub-area image signal voltages and reset signal voltages for the local areas composed of local sub-areas A, N, N, and N, and store the image signal voltages and reset signal voltages after the first stage of amplification in a double sampling sub-unit, wherein C_01 of PIX1 stores P1_A (TN-4), C_06 of PIX2 stores P2_N (TN-4), C_11 of PIX3 stores P3_N (TN-4), and C_16 of PIX4 stores P4_N (TN-4). The image signal voltages and reset signal voltages after the first stage of amplification stored in the double sampling sub-unit are sent to the column signal line through the second amplifying unit 150, wherein C_02 of PIX1 stores P1_N, C_08 of PIX2 stores P2_N, C_14 of PIX3 stores P3_N, and C_20 of PIX4 stores P4_N.

[0151] In the row cycle TN-3, PIX1, PIX2, PIX3, and PIX4 respectively collect local sub-area image signal voltages and reset signal voltages for the local areas composed of local sub-areas B, A, N, and N, and store the image signal voltages and reset signal voltages after the first stage of amplification in a double sampling sub-unit, wherein C_02 of PIX1 stores P1_B (TN-3), C_07 of PIX2 stores P2_A (TN-3), C_12 of PIX3 stores P3_N (TN-3), and C_17 of PIX4 stores P4_N (TN-3). The image signal voltages and reset signal voltages after the first stage of amplification stored in the double sampling sub-unit are sent to the column signal line through the second amplifying unit 150, wherein C_03 of PIX1 stores P1_N, C_09 of PIX2 stores P2_N, C_15 of PIX3 stores P3_N, and C_16 of PIX4 stores P4_N.

[0152] In the row cycle TN-2, PIX1, PIX2, PIX3, and PIX4 respectively collect local sub-area image signal voltages and reset signal voltages for the local areas composed of local sub-areas C, B, A, and N, and store the image signal voltages and reset signal voltages after the first stage of amplification in a double sampling sub-unit, wherein C_03 of PIX1 stores P1_C (TN-2), C_08 of PIX2 stores P2_B (TN-2), C_13 of PIX3 stores P3_A (TN-2), and C_18 of PIX4 stores P4_N (TN-2). The image signal voltages and reset signal voltages after the first stage of amplification stored in the double sampling sub-unit are sent to the column signal line through the second amplifying unit 150, wherein C_04 of PIX1 stores P1_N, C_10 of PIX2 stores P2_N, C_11 of PIX3 stores P3_N, and C_17 of PIX4 stores P4_N.

[0153] In the row cycle TN-1, PIX1, PIX2, PIX3, and PIX4 respectively collect local sub-area image signal voltages and reset signal voltages for the local areas composed of local sub-areas D, C, B, and A, and store the image signal voltages and reset signal voltages after the first stage of amplification in a double sampling sub-unit, wherein C_04 of PIX1 stores P1_D (TN-1), C_09 of PIX2 stores P2_C (TN-1), C_14 of PIX3 stores P3_B (TN-1), and C_19 of PIX4 stores P4_A (TN-1). The image signal voltages and reset signal voltages after the first stage of amplification stored in the double sampling sub-unit are sent to the column signal line through the second amplifying unit 150, wherein C_05 of PIX1 stores P1_N, C_06 of PIX2 stores P2_N, C_12 of PIX3 stores P3_N, and C_18 of PIX4 stores P4_N.

[0154] In the TN row cycle, PIX1, PIX2, PIX3, and PIX4 respectively collect local sub-region image signal voltages and reset signal voltages for local regions composed of local sub-regions E, D, C, and B, and store the image signal voltages and reset signal voltages after the first stage of amplification in a double sampling sub-unit, wherein C_05 of PIX1 stores P1_E (TN), C_10 of PIX2 stores P2_D (TN), C_15 of PIX3 stores P3_C (TN), and C_20 of PIX4 stores P4_B (TN). The image signal voltages and reset signal voltages after the first stage of amplification stored in the double sampling sub-unit are sent to the column signal line through the second amplifying unit 150, wherein C_01 of PIX1 stores P1_A (TN-4), C_07 of PIX2 stores P2_A (TN-3), C_13 of PIX3 stores P3_A (TN-2), and C_19 of PIX4 stores P4_A (TN-1).

[0155] The local sub-region image signal voltage and reset signal voltage after the first-stage amplification of the four pixels P IX1, P IX2, P IX3, and P IX4 for the four samplings of the local sub-region A in the four sampling periods TN-4, TN-3, TN-2, and TN-1 are sent to the four column signal lines through the second amplification unit and connected to the column amplifier to complete signal superposition, so as to obtain the fused and superimposed image signal voltage and reset signal voltage of the local sub-region A, and then obtain the local sub-region A image after time delay integration, thereby achieving the beneficial effect of improving the signal-to-noise ratio.

[0156] In the TN+1 cycle, PIX1, PIX2, P IX3 and PIX4 respectively collect local sub-region image signal voltages and reset signal voltages for the local regions composed of local sub-regions F, E, D, and C, and store the image signal voltages and reset signal voltages after the first stage of amplification in a double sampling sub-unit, wherein C_01 of PIX1 stores P1_F (TN+1), C_06 of PIX2 stores P2_E (TN+1), C_11 of PIX3 stores P3_D (TN+1), and C_16 of PIX4 stores P4_C (TN+1). The image signal voltages and reset signal voltages after the first stage of amplification stored in the double sampling sub-unit are sent to the column signal line through the second amplifying unit 150, wherein C_02 of PIX1 stores P1_B (TN-3), C_08 of PIX2 stores P2_B (TN-2), C_14 of PIX3 stores P3_B (TN-1), and C_20 of PIX4 stores P4_B (TN).

[0157] The local sub-region image signal voltage and reset signal voltage after the first-stage amplification of the four pixels P IX1, P IX2, P IX3, and PIX4 for four samplings of the local sub-region B in four sampling periods TN-3, TN-2, TN-1, and TN are sent to four column signal lines through the second amplification unit and connected to the column amplifier to complete signal superposition, so as to obtain the fused and superimposed image signal voltage and reset signal voltage of the local sub-region B, and then obtain the local sub-region B image after time delay integration, thereby achieving the beneficial effect of improving the signal-to-noise ratio.

[0158] In the TN+2 cycle, PIX1, PIX2, P IX3 and PIX4 respectively collect local sub-region image signal voltages and reset signal voltages for the local regions composed of local sub-regions G, F, E, and D, and store the image signal voltages and reset signal voltages after the first stage of amplification in a double sampling sub-unit, wherein C_02 of PIX1 stores P1_G (TN+2), C_07 of PIX2 stores P2_F (TN+2), C_12 of PIX3 stores P3_E (TN+2), and C_17 of PIX4 stores P4_D (TN+2). The image signal voltages and reset signal voltages after the first stage of amplification stored in the double sampling sub-unit are sent to the column signal line through the second amplifying unit 150, wherein C_03 of PIX1 stores P1_C (TN-2), C_09 of PIX2 stores P2_C (TN-1), C_15 of PIX3 stores P3_C (TN), and C_16 of PIX4 stores P4_C (TN+1).

[0159] The local sub-region image signal voltage and reset signal voltage after the first-stage amplification of the four pixels P IX1, P IX2, P IX3, and PIX4 for four samplings of the local sub-region C in four sampling periods TN-2, TN-1, TN, and TN+1 are sent to four column signal lines through the second amplification unit and connected to the column amplifier to complete signal superposition, so as to obtain the fused and superimposed image signal voltage and reset signal voltage of the local sub-region C, and then obtain the local sub-region C image after time delay integration, thereby achieving the beneficial effect of improving the signal-to-noise ratio.

[0160] In the TN+3 cycle, PIX1, PIX2, P IX3 and PIX4 respectively collect local sub-region image signal voltages and reset signal voltages for the local regions composed of local sub-regions H, G, F, and E, and store the image signal voltages and reset signal voltages after the first stage of amplification in a double sampling sub-unit, wherein C_03 of PIX1 stores P1_H (TN+3), C_08 of PIX2 stores P2_G (TN+3), C_13 of PIX3 stores P3_F (TN+3), and C_18 of PIX4 stores P4_E (TN+3). The image signal voltages and reset signal voltages after the first stage of amplification stored in the double sampling sub-unit are sent to the column signal line through the second amplifying unit 150, wherein C_04 of PIX1 stores P1_D (TN-1), C_10 of PIX2 stores P2_D (TN), C_11 of PIX3 stores P3_D (TN+1), and C_17 of PIX4 stores P4_D (TN+2).

[0161] The local sub-region image signal voltage and reset signal voltage after the first-stage amplification of the four pixels P IX1, P IX2, P IX3, and PIX4 for four samplings of the local sub-region D in four sampling periods TN-1, TN, TN+1, and TN+2 are sent to four column signal lines through the second amplification unit and connected to the column amplifier to complete signal superposition, so as to obtain the fused and superimposed image signal voltage and reset signal voltage of the local sub-region D, and then obtain the local sub-region D image after time delay integration, thereby achieving the beneficial effect of improving the signal-to-noise ratio.

[0162] According to the above method, in each row period, PIX1, PIX2, PIX3, and PIX4 can collect signals for a local area composed of local sub-areas of the target object to the corresponding multi-sampling switch unit to obtain a group of image signal voltages and reset signal voltages after primary amplification. Further, image analysis and fusion processing are performed on multiple groups of image signal voltages and reset signal voltages after primary amplification obtained in multiple row periods, and the image signal voltages and reset signal voltages of the local sub-areas after primary amplification collected by the photosensitive pixels PIX1, PIX2, PIX3, and PIX4 at different times for the same local sub-area are sent to the column signal line through the second amplification unit, and then superimposed and fused through the analog circuit to obtain the image signal voltage and reset signal voltage of the fused local sub-area corresponding to each local sub-area, and then the local sub-area image after time delay integration can be obtained through the image signal voltage and reset signal voltage of the fused local sub-area. Further, multiple local sub-area images after time delay integration are integrated to obtain the target acquisition image after time delay integration of the target object.

[0163] Reference Figure 4AAccording to some embodiments of the present application, inside the multi-sampling switch capacitor unit 140, a first number (e.g., 4 or other numbers) of sampling signal subunits 1430 connected in parallel are provided between the sampling receiving end 141 and the sampling output end 142, and the sampling output end 142 is connected to a second number (e.g., 4 or other numbers) of sampling reset subunits 1440, and one sampling signal subunit 1430 and one sampling reset subunit 1440 constitute one dual sampling subunit;

[0164] The sampling signal subunit 1430 includes a third sampling switch 1434 and a third reading switch 1435 which are sequentially arranged in series at the sampling receiving end 141 and the sampling output end 142; wherein a branch is led out from the connection line between the third sampling switch 1434 and the third reading switch 1435, connected to one end of the third sampling capacitor 1436, and the other end of the third sampling capacitor 1436 is grounded;

[0165] The sampling reset subunit 1440 has a branch line extending from the sampling output terminal 142, connected to one end of a first sampling switch 1444, the other end of the first sampling switch 1444 is connected to one end of a first sampling capacitor 1445, and the other end of the first sampling capacitor 1445 is grounded;

[0166] The third sampling switch 1434 is configured with a third sampling control terminal, the third reading switch 1435 is configured with a third reading control terminal, and the first reading switch 1444 is configured with a first reading control terminal; wherein the third sampling control terminal, the third reading control terminal and the first reading control terminal serve as storage control interfaces for controlling the multi-sampling switch capacitor unit 140 to access the image signal voltage and reset signal voltage after the first stage of amplification.

[0167] It should be noted that, since one end of the third sampling capacitor 1436 is connected between the third sampling switch 1434 and the third reading switch 1435, the image signal voltage after the first stage of amplification can be sampled or read only by changing the on and off states of the third sampling switch 1434 and the third reading switch 1435.

[0168] It should be noted that, since the first sampling switch 1444 is connected to the connection line between the third reading switch 1435 and the sampling output terminal 142, the on-off state changes of the third sampling switch 1434, the third reading switch 1435 and the first sampling switch 1444 can realize the sampling of the reset signal voltage after the first stage amplification by using the first sampling capacitor 1445, and the reading of the reset signal voltage can be realized by the on-off state changes of the first sampling switch 1444.

[0169] Reference Figure 4BAccording to some embodiments of the present application, a transmission switch is provided between the photosensitive element 110 and the first amplifying unit 130, and the transmission switch is used to control the transmission of the image photoelectric signal collected from the photosensitive element 110 to the suspension node 120 to become an image signal voltage.

[0170] According to some more specific embodiments of the present application. Figure 4B As shown, the control signals of each component in the photosensitive pixel are as follows:

[0171] The global reset switch 122 is controlled by a control signal GRST;

[0172] The first control terminal 132 of the first amplifying unit 130 is controlled by a control signal PC;

[0173] The transmission switch is controlled by the control signal TX;

[0174] The second control terminal 152 of the second amplifying unit 150 is controlled by a control signal RRST;

[0175] The third sampling control terminals of the four sampling signal subunits are respectively controlled by four control signals SSN (N=1 / 2 / 3 / 4);

[0176] The third read control terminals of the four sampling signal subunits are respectively controlled by four control signals RSN (N=1 / 2 / 3 / 4);

[0177] The first sampling and reading control terminals of the four sampling and resetting subunits are respectively controlled by four control signals SRN (N=1 / 2 / 3 / 4).

[0178] Reference Figure 4C , some more specific embodiments are shown with reference to Figure 4B Circuit timing diagram of a single pixel in FIG. Each photosensitive pixel is configured with a multi-sampling switch capacitor unit 140, and four sampling signal subunits are arranged in parallel between the sampling receiving end 141 and the sampling output end 142 in the multi-sampling switch capacitor unit 140, and the sampling output end is connected to four sampling reset subunits, wherein one sampling signal subunit and one sampling reset subunit constitute a double sampling subunit.

[0179] The operation of the photosensitive pixel in each row cycle is divided into a sampling operation cycle and a reading operation cycle. In the sampling operation cycle, one dual sampling sub-unit performs the sampling operation of the image signal voltage and the reset signal voltage after the first-stage amplification of the photosensitive pixel. In the reading operation cycle, one dual sampling sub-unit performs the reading operation of the image signal voltage and the reset signal voltage after the first-stage amplification of the photosensitive pixel. The dual sampling sub-unit that does not participate in the sampling operation and the reading operation maintains the storage of the image signal voltage and the reset signal voltage after the first-stage amplification.

[0180] When the photosensitive pixel is used to perform the sampling operation stage, a group of control signals SSN, SRN, and RSN are used to control the on and off of a group of third sampling switches, a third reading switch, and a first sampling switch. A double sampling subunit performs sampling of the image signal voltage and the reset signal voltage after the first stage of amplification. The 9 control signals SSN, SRN, and RSN of the three double sampling subunits are low to maintain the storage of the sampled image signal voltage and the reset signal voltage after the first stage of amplification: the control signal GRST is pulled high to turn on the global reset switch, and a group of control signals SSN, SRN, and RSN are triggered in turn to turn on the third sampling switch, the third reading switch, and the first sampling switch. The control signal PC is pulled high to turn on the first control terminal, clearing the first sampling capacitor 1445, i.e., the reset sampling capacitor, and the third sampling capacitor 1436, i.e., the signal sampling capacitor. Capacitor, trigger control signal GRST changes from high to low, turns off the global reset switch, and ends clearing the reset sampling capacitor and the signal sampling capacitor. A control signal SRN changes from high to low to turn off the first sampling switch, and samples the reset signal voltage after the first stage of amplification to the first sampling capacitor 1445. A control signal RSN changes from high to low to turn off the third reading switch, pulls up and then pulls down the control signal TX to control the on and off of the transmission switch, transfers the charge of the photosensitive element 110 to the suspension node 120 to become the image signal voltage, and then pulls down a control signal SSN to turn off the third sampling switch, and samples the image signal voltage after the first stage of amplification to the third sampling capacitor 1436. Then, pull up the control signal GRST to turn on the global reset switch, and pull down the control signal PC to turn off the first control end to end the sampling operation phase and start the reading operation phase.

[0181] When the photosensitive pixel is used to perform the reading operation stage, a double sampling sub-unit performs the reading of the image signal voltage and reset signal voltage after the first stage amplification from the second amplifying unit to the column signal line through the conduction and shutdown of a group of control signals SRN, SSN, and RSN, and becomes the image signal voltage and reset signal voltage after the second stage amplification. The 9 control signals SRN, SSN, and RSN of the three double sampling sub-units are low to maintain the storage of the sampled image signal voltage and reset signal voltage after the first stage amplification: the control signal RRST is pulled high and then low to control the second control end to clear the level of the sampling output end 142, and a control signal SRN is pulled high and then low to read the reset signal voltage after the first stage amplification, perform the second stage amplification, and then output it to the column signal line, and the control signal RRST is pulled high and then low to control the second control end to clear the level of the sampling output end 142 again, and the control signal RSN is pulled high and then low to read the image signal voltage after the first stage amplification, perform the second stage amplification, and then output it to the column signal line.

[0182] based on Figure 4CThe circuit timing diagram of the embodiment is shown, and one row cycle is divided into a sampling operation cycle and a reading operation cycle, and the control signals of each component in the photosensitive pixel are manipulated. In one sampling operation cycle, the image signal voltage and reset signal voltage after the first stage of amplification are sampled to the signal sampling capacitor and the reset sampling capacitor, and in one reading operation cycle, the image signal voltage and reset signal voltage after the first stage of amplification are read through the second amplifier. Specifically, the image signal voltage and reset signal voltage are amplified in one stage and stored in the double sampling subunit (i.e., sampling operation), and the image signal voltage and reset signal voltage after the first stage of amplification are read out from the double sampling subunit and output after the second stage of amplification (i.e., reading operation).

[0183] It should be understood that Figure 4C The circuit timing diagram shown is an example of controlling a photosensitive pixel. The embodiments of the present application may include, but are not limited to: Figure 4C The control process of the photosensitive pixel is shown.

[0184] When the image acquisition device provided in the embodiment of the present application includes Figure 4B The photosensitive pixels shown can be Figure 4D The illustrated embodiment performs a time delay integration (TDI) operation to capture an image of a target object. The operation timing of each photosensitive pixel can refer to Figure 4C The operation timing is shown. Specifically:

[0185] The photosensitive pixels can be presented in a matrix form in the image acquisition device. Taking a column of pixels including 4 rows of photosensitive pixels as an example, the photosensitive pixels in the 1st to 4th rows are respectively represented as PIX1, PIX2, PIX3, and PIX4. The multi-sampling switch capacitor unit 140 of each pixel has 4 double sampling sub-units, and the 4 double sampling sub-units of PIX1 for storing the image signal voltage and reset signal voltage after the first stage of amplification are respectively abbreviated as C_01 / 02 / 03 / 04, the 4 double sampling sub-units of PIX2 for storing the image signal voltage and reset signal voltage after the first stage of amplification are respectively abbreviated as C_05 / 06 / 07 / 08, the 4 double sampling sub-units of PIX3 for storing the image signal voltage and reset signal voltage after the first stage of amplification are respectively abbreviated as C_09 / 10 / 11 / 12, and the 4 double sampling sub-units of PIX4 for storing the image signal voltage and reset signal voltage after the first stage of amplification are respectively abbreviated as C_13 / 14 / 15 / 16. The image signal voltage and reset signal voltage of the same local sub-region stored in the multi-sampling capacitor unit at different times after the first stage amplification are sent to the column signal line through the respective second amplification units 150. The column signal lines of the four rows of photosensitive pixels are connected to form a column bus.

[0186] Figure 4D In a column slice, each row time, the photosensitive pixels P IX1, P IX2, P IX3, and P IX4 respectively capture a color rectangle (such as A, B, C, D, E, F, G, and H), that is, a local sub-region of the target object, and the obtained signals are the image signal voltage and reset signal voltage of the local sub-region. The 4 local sub-regions captured by 4 pixels constitute a local region, and the obtained signals are the image signal voltage and reset signal voltage of the local region.

[0187] Photosensitive pixels PIX1, PIX2, PIX3, PIX4.

[0188] The corresponding relationship of signal sampling of local sub-areas A, B, C, D, E, F, G, H, and N by PIX1 is abbreviated as P1_A, P1_B, P1_C, P1_D, P1_E, P1_F, P1_G, P1_H, P1_N,

[0189] The corresponding relationship between PIX2's signal sampling of local sub-areas A, B, C, D, E, F, G, H, and N is abbreviated as P2_A, P2_B, P2_C, P2_D, P2_E, P2_F, P2_G, P2_H, P2_N,

[0190] The corresponding relationship between PIX3's signal sampling of local sub-areas A, B, C, D, E, F, G, H, and N is abbreviated as P3_A, P3_B, P3_C, P3_D, P3_E, P3_F, P3_G, P3_H, P3_N,

[0191] The corresponding relationship between PIX4's signal sampling of local sub-areas A, B, C, D, E, F, G, H, and N is abbreviated as P4_A, P4_B, P4_C, P4_D, P4_E, P4_F, P4_G, P4_H, and P4_N.

[0192] Reference Figure 4D The sampling and reading method of the four rows of photosensitive pixels in the image acquisition device and the TDI stacking operation timing can be as follows: Figure 4D As shown. Among them, TN-3, TN-2, TN-1, TN, TN+1, TN+2, TN+3, respectively refer to different row periods. In each row period, the four pixels PIX1, PIX2, PIX3, PIX4 on the column slice respectively collect the image signal voltage and reset signal voltage of the target object, wherein each pixel corresponds to a local sub-region to collect the image signal voltage and reset signal voltage of the local sub-region, and store them in a double sampling sub-unit through their respective first amplification units 130.

[0193] In the sampling operation cycle of the TN-3 row period, PIX1, PIX2, PIX3, and PIX4 respectively collect the local sub-area image signal voltage and reset signal voltage of the local area composed of local sub-areas A, N, N, and N, and store the image signal voltage and reset signal voltage after the first stage of amplification in a double sampling sub-unit, among which C_01 of PIX1 stores P1_A (TN-3), C_05 of PIX2 stores P2_N (TN-3), C_09 of PIX3 stores P3_N (TN-3), and C_13 of PIX4 stores P4_N (TN-3).

[0194] In the read operation cycle of the row cycle TN-3, the first-stage amplified image signal voltage and reset signal voltage stored in the double sampling subunit are sent to the column bus through the second amplifying unit 150, among which C_02 of PIX1 stores P1_N, C_07 of PIX2 stores P2_N, C_12 of PIX3 stores P3_N, and C_13 of PIX4 stores P4_N.

[0195] In the sampling operation cycle of the TN-2 row period, PIX1, PIX2, PIX3, and PIX4 respectively collect the local sub-area image signal voltage and reset signal voltage of the local area composed of local sub-areas B, A, N, and N, and store the image signal voltage and reset signal voltage after the first stage of amplification in a double sampling sub-unit, among which C_02 of PIX1 stores P1_B (TN-2), C_06 of PIX2 stores P2_A (TN-2), C_10 of PIX3 stores P3_N (TN-2), and C_14 of PIX4 stores P4_N (TN-2).

[0196] In the read operation cycle of the row cycle TN-2, the first-stage amplified image signal voltage and reset signal voltage stored in the double sampling subunit are sent to the column bus through the second amplifying unit 150, among which C_03 of PIX1 stores P1_N, C_08 of PIX2 stores P2_N, C_09 of PIX3 stores P3_N, and C_14 of PIX4 stores P4_N.

[0197] In the sampling operation cycle of the TN-1 line period, PIX1, PIX2, PIX3, and PIX4 respectively collect the local sub-area image signal voltage and reset signal voltage of the local area composed of local sub-areas C, B, A, and N, and store the image signal voltage and reset signal voltage after the first stage of amplification in a double sampling sub-unit, among which C_03 of PIX1 stores P1_C (TN-1), C_07 of PIX2 stores P2_B (TN-1), C_11 of PIX3 stores P3_A (TN-1), and C_15 of PIX4 stores P4_N (TN-1).

[0198] In the read operation cycle of the row cycle TN-1, the first-stage amplified image signal voltage and reset signal voltage stored in the double sampling subunit are sent to the column bus through the second amplifying unit 150, among which C_04 of PIX1 stores P1_N, C_05 of PIX2 stores P2_N, C_10 of PIX3 stores P3_N, and C_15 of PIX4 stores P4_N.

[0199] In the sampling operation cycle of the TN line period, PIX1, PIX2, PIX3, and PIX4 respectively collect the local sub-area image signal voltage and reset signal voltage of the local area composed of local sub-areas D, C, B, and A, and store the image signal voltage and reset signal voltage after the first stage of amplification in a double sampling sub-unit, among which C_04 of PIX1 stores P1_D (TN), C_08 of PIX2 stores P2_C (TN), C_12 of PIX3 stores P3_B (TN), and C_16 of PIX4 stores P4_A (TN).

[0200] In the read operation cycle of the TN row cycle, the first-stage amplified image signal voltage and reset signal voltage stored in the double sampling subunit are sent to the column bus through the second amplification unit 150, among which C_01 of PIX1 stores P1_A (TN-3), C_06 of PIX2 stores P2_A (TN-2), C_11 of PIX3 stores P3_A (TN-1), and C_16 of PIX4 stores P4_A (TN). The local sub-region image signal voltage and reset signal voltage after the first-stage amplification of the four pixels PIX1, PIX2, PIX3, and PIX4 for four times of sampling in the local sub-region A in four sampling operation cycles TN-3, TN-2, TN-1, and TN are simultaneously sent to the column bus through the second amplification unit, and the image signal voltage and reset signal voltage after the second-stage amplification of the four pixels in the local sub-region A are time-shared on the column bus through voltage averaging to reduce noise, and the noise-reduced image signal voltage and reset signal voltage of the local sub-region A are obtained, thereby achieving the beneficial effect of improving the signal-to-noise ratio, and then the image of the local sub-region A after time delay integration is obtained.

[0201] In the sampling operation cycle of the row period TN+1, PIX1, PIX2, PIX3, and PIX4 respectively collect the local sub-area image signal voltage and reset signal voltage of the local area composed of local sub-areas E, D, C, and B, and store the image signal voltage and reset signal voltage after the first stage of amplification in a double sampling sub-unit, among which C_01 of PIX1 stores P1_E(TN+1), C_05 of PIX2 stores P2_D(TN+1), C_09 of PIX3 stores P3_C(TN+1), and C_13 of PIX4 stores P4_B(TN+1).

[0202] In the read operation cycle of the row cycle TN+1, the first-stage amplified image signal voltage and reset signal voltage stored in the double sampling subunit are sent to the column bus through the second amplifying unit 150, among which C_02 of PIX1 stores P1_B(TN-2), C_07 of PIX2 stores P2_B(TN-1), C_12 of PIX3 stores P3_B(TN), and C_13 of PIX4 stores P4_B(TN+1). The local sub-region image signal voltage and reset signal voltage after primary amplification of the four pixels PIX1, PIX2, PIX3, and PIX4 for four sampling operation cycles TN-2, TN-1, TN, and TN+1 of the local sub-region B are simultaneously sent to the column bus through the second amplification unit, and the image signal voltage and reset signal voltage of the four pixels after secondary amplification in the local sub-region B are time-shared on the column bus through voltage averaging to reduce noise, thereby obtaining the image signal voltage and reset signal voltage of the local sub-region B after noise reduction, achieving the beneficial effect of improving the signal-to-noise ratio, and then obtaining the image of the local sub-region B after time delay integration.

[0203] In the sampling operation cycle of the row period TN+2, PIX1, PIX2, PIX3, and PIX4 respectively collect the local sub-area image signal voltage and reset signal voltage of the local area composed of local sub-areas F, E, D, and C, and store the image signal voltage and reset signal voltage after the first stage of amplification in a double sampling sub-unit, among which C_02 of PIX1 stores P1_F(TN+2), C_06 of PIX2 stores P2_E(TN+2), C_10 of PIX3 stores P3_D(TN+2), and C_14 of PIX4 stores P4_C(TN+2).

[0204] In the read operation cycle of the row cycle TN+2, the first-stage amplified image signal voltage and reset signal voltage stored in the double sampling subunit are sent to the column bus through the second amplifying unit 150, among which C_03 of PIX1 stores P1_C(TN-1), C_08 of PIX2 stores P2_C(TN), C_09 of PIX3 stores P3_C(TN+1), and C_14 of PIX4 stores P4_C(TN+2). The image signal voltage and reset signal voltage of the local sub-region after primary amplification of the four pixels PIX1, PIX2, PIX3, and PIX4 for four times of sampling in the local sub-region C in four sampling operation cycles TN-1, TN, TN+1, and TN+2 are simultaneously sent to the column bus through the second amplification unit, and the image signal voltage and reset signal voltage of the four pixels in the local sub-region C after secondary amplification are time-shared on the column bus through voltage averaging to reduce noise, thereby obtaining the image signal voltage and reset signal voltage of the local sub-region C after noise reduction, achieving the beneficial effect of improving the signal-to-noise ratio, and then obtaining the image of the local sub-region C after time delay integration.

[0205] In the sampling operation cycle of the row period TN+3, PIX1, PIX2, PIX3, and PIX4 respectively collect the local sub-region image signal voltage and reset signal voltage of the local region composed of the local sub-regions G, F, E, and D, and store the image signal voltage and reset signal voltage after the first stage of amplification in a double sampling sub-unit, where C_03 of PIX1 stores P1_G (TN+3), C_07 of PIX2 stores P2_F (TN+3), C_11 of PIX3 stores P3_E (TN+3), and C_15 of PIX4 stores P4_D (TN+3).

[0206] In the read operation cycle of the row cycle TN+3, the first-stage amplified image signal voltage and reset signal voltage stored in the double sampling subunit are sent to the column bus through the second amplifying unit 150, among which P1_D(TN) stored in C_04 of PIX1, P2_D(TN+1) stored in C_05 of PIX2, P3_D(TN+2) stored in C_10 of PIX3, and P4_D(TN+3) stored in C_15 of PIX4. The image signal voltage and reset signal voltage of the local sub-region after primary amplification of the four pixels PIX1, PIX2, PIX3, and PIX4 for four times of sampling in the local sub-region D in four sampling operation cycles TN, TN+1, TN+2, and TN+3 are simultaneously sent to the column bus through the second amplification unit, and the image signal voltage and reset signal voltage of the four pixels in the local sub-region D after secondary amplification are time-shared on the column bus through voltage averaging to reduce noise, thereby obtaining the image signal voltage and reset signal voltage of the local sub-region D after noise reduction, achieving the beneficial effect of improving the signal-to-noise ratio, and then obtaining the image of the local sub-region D after time delay integration.

[0207] According to the above method, in each row period, PIX1, PIX2, PIX3, and PIX4 can collect signals for a local area composed of local sub-areas of the target object to a double sampling sub-unit in the corresponding multi-sampling switch unit to obtain a set of image signal voltages and reset signal voltages after primary amplification. Further, image analysis and fusion processing are performed on multiple sets of image signal voltages and reset signal voltages after primary amplification obtained in multiple row periods, and the image signal voltages and reset signal voltages of the local sub-areas after primary amplification collected by the photosensitive pixels PIX1, PIX2, PIX3, and PIX4 at different times for the same local sub-area are sent to the column bus through the second amplification unit for direct superposition and fusion, so as to obtain the image signal voltages and reset signal voltages of the fused local sub-areas corresponding to each local sub-area, and then the local sub-area image after time delay integration can be obtained through the image signal voltages and reset signal voltages of the fused local sub-areas. Further, multiple local sub-area images after time delay integration are integrated to obtain the target acquisition image after time delay integration of the target object.

[0208] Reference Figure 5A , according to some embodiments of the present application, the first amplification unit 130 includes a first source follower 134;

[0209] The drain of the first source follower 134 is used to connect to the second working voltage;

[0210] The gate of the first source follower 134 is connected to the photosensitive element 110 via the floating node 120 as the first receiving terminal 131;

[0211] The source of the first source follower 134 is connected to the sampling receiving terminal 141 as the first output terminal 133 .

[0212] It should be noted that there are various optional embodiments of the first amplifying unit 130, for example Figure 4A The first amplifying unit 130 shown includes a first source follower 134 and a current control switch 135. Figure 5AIn the illustrated embodiment, the first amplifier unit 130 may also not include the current control switch 135, and only the first source follower 134 is used as the first amplifier unit 130. Specifically, the drain of the first source follower 134 is used to connect the second working voltage; the gate of the first source follower 134 is connected to the photosensitive element 110 via the suspension node 120 as the first receiving terminal 131; the source of the first source follower 134 is connected to the sampling receiving terminal 141 as the first output terminal 133. It should be noted that, in the embodiment of the present application, the second working voltage connected to the drain of the first source follower 134 is used as a control signal to adjust the first-stage amplification of the image signal voltage and the reset signal voltage by the first amplifier unit 130. That is, in the embodiment of the present application, the drain of the first source follower 134 is connected to the second working voltage as the first control terminal 132, and by adjusting the level of the second working voltage, the first amplifier unit 130 can be controlled to perform the first-stage amplification of the image signal voltage and the reset signal voltage.

[0213] Reference Figure 5A According to some embodiments of the present application, inside the multi-sampling switch capacitor unit 140, a first sampling circuit is provided between the sampling receiving terminal 141 and the sampling output terminal 142, and a global sampling switch 1451 is provided in the first sampling circuit, the input terminal of the global sampling switch 1451 is connected to the sampling receiving terminal 141, and the output terminal of the global sampling switch 1451 is connected to the sampling output terminal 142; a plurality of sampling sub-units between the sampling receiving terminal 141 and the sampling output terminal 142 include four sampling signal sub-units 1430 and one sampling reset sub-unit 1440;

[0214] The sampling signal subunit 1430 is connected to the connection line between the output end of the global sampling switch 1451 and the sampling output end 142 through the first side branch port; wherein each sampling signal subunit 1430 includes a second sampling branch connected to the first side branch port;

[0215] The sampling reset subunit 1440 is connected to the connection line between the output end of the global sampling switch 1451 and the sampling output end 142 through the second side branch port; wherein each sampling reset subunit 1440 includes a third sampling branch connected to the second side branch port;

[0216] The second reading branch circuit is connected in series with a second reading switch 1437 and a second reading capacitor 1438 between the first side branch port and the ground; wherein the second reading switch 1437 is provided with a second reading control interface;

[0217] The third reading branch circuit is connected in series with a third reading switch 1446 and a third reading capacitor 1447 between the second side branch port and the ground. The third reading switch 1446 is provided with a third reading control interface.

[0218] The control end of the global sampling switch 1451, the second sampling control interface and the third sampling control interface are used as storage control interfaces to control the multi-sampling switch capacitor unit 140 to access the image signal voltage and reset signal voltage after the first stage of amplification.

[0219] It should be noted that the global sampling switch 1451 is set in the first sampling circuit. In addition, the second sampling branch connected in series with the second sampling switch 1437 and the second sampling capacitor 1438 is connected to the first sampling circuit through the first side branch port, and the third sampling branch connected in series with the third sampling switch 1446 and the third sampling capacitor 1447 is connected to the first sampling circuit through the second side branch port. In this way, by controlling the global sampling switch 1451, the second sampling branch and the third sampling branch can be used to sample or read the image signal voltage and reset signal voltage after the first stage of amplification.

[0220] Reference Figure 5B According to some embodiments of the present application, a transmission switch is provided between the photosensitive element 110 and the first amplifying unit 130, and the transmission switch is used to control the transmission of the image photoelectric signal collected from the photosensitive element 110 to the suspension node 120 to become an image signal voltage.

[0221] According to some more specific embodiments of the present application. Figure 5B As shown, the control signals of each component in the photosensitive pixel are as follows:

[0222] The global reset switch 122 is controlled by a control signal GRST;

[0223] The first control terminal 132 of the first amplifying unit 130 is controlled by a control signal VSF, and the control signal VSF corresponds to the second working voltage;

[0224] The transmission switch is controlled by the control signal TX;

[0225] The control terminal of the global sampling switch 1451 is controlled by a control signal GSMP;

[0226] The second control terminal 152 of the second amplifying unit 150 is controlled by a control signal RRST;

[0227] The second sampling and reading control interfaces of the four sampling signal subunits are respectively controlled by four control signals SSN (N=1 / 2 / 3 / 4);

[0228] The third sampling and reading control interface of one sampling and resetting subunit is controlled by the control signal SR1.

[0229] Reference Figure 5C , some more specific embodiments are shown with reference to Figure 5BThe circuit timing diagram of a single pixel in FIG. Each photosensitive pixel is configured with a multi-sampling switch capacitor unit 140, and five sampling subunits are arranged inside the multi-sampling switch capacitor unit 140 between the sampling receiving terminal 141 and the sampling output terminal 142. Specifically, it includes four sampling signal subunits 1430 and one sampling reset subunit 1440.

[0230] Each row cycle is divided into a sampling operation cycle and a reading operation cycle. In the sampling operation cycle, one sampling signal sub-unit and one sampling reset sub-unit perform sampling operations on the image signal voltage and reset signal voltage after the first-level amplification of the image signal collected by the photosensitive pixels. In the reading operation cycle, one sampling signal sub-unit and one sampling reset sub-unit perform reading operations on the image signal voltage and reset signal voltage after the first-level amplification of the image signal collected by the photosensitive pixels. The sampling sub-units that do not participate in the sampling operation and the reading operation maintain the storage of the image signal voltage and the reset signal voltage.

[0231] When the photosensitive pixel is used to perform a sampling operation cycle, a sampling signal subunit and a sampling reset subunit control the second sampling switch and the third sampling switch to be turned on and off through a control signal SSN and SR1 to perform sampling of the image signal voltage and the reset signal voltage. The control signal SSN of the three sampling signal subunits is low to maintain the storage of the sampled image signal voltage. The control signal GRST is pulled high to turn on the global reset switch, the control signal VSF is pulled low, the control signal GSMP is pulled high to turn on the global sampling switch GSMP, the control signal SR1 and an SSN are pulled high to turn on the second sampling switch and the third sampling switch, and the corresponding reset sampling capacitor and signal sampling capacitor are cleared. A control signal SSN is pulled low, the control signal VSF is pulled high, and the control signal GRST is pulled low to turn off the global reset switch, and the sampling capacitor is cleared. The control signal SR1 is pulled low to control the third sampling switch, and the reset signal voltage is sampled to the third sampling capacitor 1447. The control signal TX is pulled high and then low to control the on and off of the transmission switch, and the image photoelectric signal charge of the photosensitive element 110 is transferred to the suspension node 120 to become the image signal voltage. The control signal SSN is pulled high and then low to control the second sampling switch to sample the image signal voltage to the second sampling capacitor 1438. The control signal GSMP is pulled low to turn off the global sampling switch, and the control signal GRST is pulled high to turn on the global reset switch to complete the sampling operation phase.

[0232] When the photosensitive pixel is used to perform a reading operation cycle, a sampling signal subunit and a sampling reset subunit control the conduction and disconnection of the second sampling and reading switches and the third sampling and reading switches through control signals SSN and SR1 to perform the reading of the image signal voltage and the reset signal voltage. The control signal SSN of the three sampling signal subunits is low to maintain the storage of the sampled image signal. The control signal RRST is pulled up and then pulled down to control the second control end to clear the level of the sampling output end 142, and the control signal SR1 is pulled up and then pulled down to control the conduction and then disconnection of the third sampling and reading switch, and the reset signal voltage after the first stage of amplification is read and output to the column signal line after the second stage of amplification. The control signal RRST is pulled up and then pulled down to control the second control end to clear the level of the sampling output end 142 again, and a signal SSN is pulled up and then pulled down to control the conduction and then disconnection of the second sampling and reading switch, and the image signal voltage after the first stage of amplification is read and output to the column signal line after the second stage of amplification.

[0233] based on Figure 5C The circuit timing diagram of the embodiment is shown, and one row cycle is divided into a sampling operation cycle and a reading operation cycle, and the control signals of each component in the photosensitive pixel are manipulated. In one sampling operation cycle, the image signal voltage and reset signal voltage after the first stage of amplification are sampled to the signal sampling capacitor and the reset sampling capacitor, and in one reading operation cycle, the image signal voltage and reset signal voltage after the first stage of amplification are read through the second amplification unit. Specifically, the image signal voltage and reset signal voltage are amplified in one stage and stored in the sampling subunit (that is, the sampling operation), and the image signal voltage and reset signal voltage are read out from the sampling subunit and output after the second stage of amplification (that is, the reading operation).

[0234] It should be understood that Figure 5C The circuit timing diagram shown is an example of controlling a photosensitive pixel. The embodiments of the present application may include, but are not limited to: Figure 5C The control process of the photosensitive pixel is shown.

[0235] When the image acquisition device provided in the embodiment of the present application includes Figure 5B The photosensitive pixels shown can be Figure 5D The illustrated embodiment performs a time delay integration (TDI) operation to capture an image of a target object. The operation timing of each photosensitive pixel can refer to Figure 5C The operation timing is shown. Specifically:

[0236] The photosensitive pixels can be presented in a matrix form in the image acquisition device. Taking a column of pixels including 4 rows of photosensitive pixels as an example, the photosensitive pixels in the 1st to 4th rows are respectively represented as PIX1, PIX2, PIX3, and PIX4, and the multi-sampling switch capacitor unit 140 of each pixel has 4 sampling signal subunits 1430 and 1 sampling reset subunit 1440. The 4 sampling signal subunits 1430 of PIX1 for storing the image signal voltage after the first stage of amplification are respectively abbreviated as C_01 / 02 / 03 / 04, and the 1 sampling reset subunit 1440 for storing the reset signal voltage after the first stage of amplification is C_R1. The 4 sampling signal subunits 1430 of PIX2 for storing the image signal voltage after the first stage of amplification are respectively abbreviated as C_05 / 06 / 07 / 08, and the 1 sampling reset subunit 1440 for storing the reset signal voltage after the first stage of amplification is C_R2. The four sampling signal subunits 1430 of PIX3 for storing the image signal voltage after the first stage of amplification are abbreviated as C_09 / 10 / 11 / 12, and the one sampling reset subunit 1440 for storing the reset signal voltage after the first stage of amplification is C_R3. The four sampling signal subunits 1430 of PIX4 for storing the image signal voltage after the first stage of amplification are abbreviated as C_13 / 14 / 15 / 16, and the one sampling reset subunit 1440 for storing the reset signal voltage after the first stage of amplification is C_R4. The image signal voltage and reset signal voltage after the first stage of amplification of the same local sub-area of ​​shooting at different times stored in the multi-sampling capacitor unit in PIX1, PIX2, PIX3, and PIX4 are sent to the column signal line through their respective second amplifier units 150.

[0237] Figure 5D In a column slice, each row time, the photosensitive pixels P IX1, P IX2, P IX3, and P IX4 respectively capture a color rectangle (such as A, B, C, D, E, F, G, H), that is, a local sub-region of the target object, and obtain the local sub-region image signal voltage and reset signal voltage. The 4 local sub-regions captured by 4 pixels constitute a local region, and the obtained signals are the local image signal voltage and reset signal voltage.

[0238] Photosensitive pixels P IX1, P IX2, P IX3, P IX4,

[0239] The corresponding relationship of signal sampling of local sub-areas A, B, C, D, E, F, G, H, and N by PIX1 is abbreviated as P1_A, P1_B, P1_C, P1_D, P1_E, P1_F, P1_G, P1_H, P1_N,

[0240] The corresponding relationship of signal sampling of local sub-areas A, B, C, D, E, F, G, H, and N by PIX2 is abbreviated as P2_A, P2_B, P2_C, P2_D, P2_E, P2_F, P2_G, P2_H, P2_N,

[0241] The corresponding relationship between the signal sampling of the local sub-areas A, B, C, D, E, F, G, H, and N by PIX3 is abbreviated as P3_A, P3_B, P3_C, P3_D, P3_E, P3_F, P3_G, P3_H, P3_N,

[0242] Among them, the corresponding relationship between the signal sampling of local sub-areas A, B, C, D, E, F, G, H, and N by PIX4 is abbreviated as P4_A, P4_B, P4_C, P4_D, P4_E, P4_F, P4_G, P4_H, and P4_N.

[0243] Reference Figure 5D The sampling and reading method of the four rows of photosensitive pixels in the image acquisition device and the TDI stacking operation timing can be as follows: Figure 5D As shown. Among them, TN-3, TN-2, TN-1, TN, TN+1, TN+2, TN+3, respectively refer to different row periods. In each row period, the four pixels P IX1, P IX2, P IX3, P IX4 on the column slice respectively collect image signal voltage and reset signal voltage of the target object, wherein each pixel corresponds to a local sub-region to collect the image signal voltage and reset signal voltage of the local sub-region, and store them into one sampling signal sub-unit and one sampling reset sub-unit through their respective first amplification units 130.

[0244] In the sampling operation period of the TN-3 row period, P IX1, P IX2, P IX3, and P IX4 respectively collect the local sub-area image signal voltage and reset signal voltage of the local area composed of local sub-areas A, N, N, and N, and store the image signal voltage and reset signal voltage after the first stage of amplification in a sampling signal sub-unit and a sampling reset sub-unit, wherein C_01 of P IX1 stores the image signal voltage of P1_A (TN-3), C_06 of P IX2 stores the image signal voltage of P2_N (TN-3), C_11 of P IX3 stores the image signal voltage of P3_N (TN-3), C_16 of P IX4 stores the image signal voltage of P4_N (TN-3), and C_R4 of P IX4 stores the reset signal voltage of P4_N (TN-3).

[0245] In the reading operation cycle of the row cycle TN-3, the first-stage amplified image signal voltage and reset signal voltage stored in the sampling signal subunit and the sampling reset subunit are sent to the column signal line through the second amplifying unit 150, wherein C_02 of P IX1 stores the image signal voltage of P1_N, C_08 of P IX2 stores the image signal voltage of P2_N, C_14 of P IX3 stores the image signal voltage of P3_N, C_20 of P IX4 stores the image signal voltage of P4_N, and C_R4 of P IX4 stores the reset signal voltage of P4_N.

[0246] In the sampling operation period of the TN-2 line period, PIX1, PIX2, PIX3, and PIX4 respectively collect the local sub-area image signal voltage and reset signal voltage for the local area composed of local sub-areas B, A, N, and N, and store the image signal voltage and reset signal voltage after the first stage of amplification in a sampling signal sub-unit and a sampling reset sub-unit, wherein C_02 of PIX1 stores the image signal voltage of P1_B (TN-2), C_07 of PIX2 stores the image signal voltage of P2_A (TN-2), C_12 of PIX3 stores the image signal voltage of P3_N (TN-2), C_17 of PIX4 stores the image signal voltage of P4_N (TN-2), and C_R4 of PIX4 stores the reset signal voltage of P4_N (TN-2).

[0247] In the read operation cycle of the row cycle TN-2, the first-stage amplified image signal voltage and reset signal voltage stored in the sampling signal subunit and the sampling reset subunit are sent to the column signal line through the second amplifying unit 150, among which C_03 of PIX1 stores the image signal voltage of P1_N, C_09 of PIX2 stores the image signal voltage of P2_N, C_15 of PIX3 stores the image signal voltage of P3_N, C_16 of PIX4 stores the image signal voltage of P4_N, and C_R4 of PIX4 stores the reset signal voltage of P4_N.

[0248] In the sampling operation cycle of the TN-1 line period, PIX1, PIX2, PIX3, and PIX4 respectively collect local sub-area image signal voltages and reset signal voltages for the local areas composed of local sub-areas C, B, A, and N, and store the image signal voltages and reset signal voltages after the first stage of amplification in a sampling signal sub-unit and a sampling reset sub-unit, wherein C_03 of PIX1 stores the image signal voltage of P1_C (TN-1), C_08 of PIX2 stores the image signal voltage of P2_B (TN-1), C_13 of PIX3 stores the image signal voltage of P3_A (TN-1), C_18 of PIX4 stores the image signal voltage of P4_N (TN-1), and C_R4 of PIX4 stores the reset signal voltage of P4_N (TN-1).

[0249] In the read operation cycle of the row cycle TN-1, the first-stage amplified image signal voltage and reset signal voltage stored in the sampling signal subunit and the sampling reset subunit are sent to the column signal line through the second amplifying unit 150, among which C_04 of PIX1 stores the image signal voltage of P1_N, C_10 of PIX2 stores the image signal voltage of P2_N, C_11 of PIX3 stores the image signal voltage of P3_N, C_17 of PIX4 stores the image signal voltage of P4_N, and C_R4 of PIX4 stores the reset signal voltage of P4_N.

[0250] In the sampling operation period of the TN line period, PIX1, PIX2, PIX3, and PIX4 respectively collect local sub-area image signal voltages and reset signal voltages for the local areas composed of local sub-areas D, C, B, and A, and store the image signal voltages and reset signal voltages after the first stage of amplification in a sampling signal sub-unit and a sampling reset sub-unit, wherein C_04 of PIX1 stores the image signal voltage of P1_D (TN), C_09 of PIX2 stores the image signal voltage of P2_C (TN), C_14 of PIX3 stores the image signal voltage of P3_B (TN), C_19 of PIX4 stores the image signal voltage of P4_A (TN), and C_R4 of PIX4 stores the reset signal voltage of P4_A (TN).

[0251] In the reading operation cycle of the TN row cycle, the first-stage amplified image signal voltage and reset signal voltage stored in the sampling signal subunit and the sampling reset subunit are sent to the column signal line through the second amplifying unit 150, wherein C_01 of PIX1 stores the image signal voltage of P1_A (TN-3), C_07 of PIX2 stores the image signal voltage of P2_A (TN-2), C_13 of PIX3 stores the image signal voltage of P3_A (TN-1), C_19 of PIX4 stores the image signal voltage of P4_A (TN), and C_R4 of PIX4 stores the reset signal voltage of P4_A (TN). The local sub-region image signal voltage after the first-stage amplification of the four samples of the local sub-region A by the four pixels PIX1, PIX2, PIX3, and PIX4 is sent to the four column signal lines through the second amplification unit and connected to the column amplifier to complete signal superposition, so as to obtain the reset signal voltage of the local sub-region A and the fused and superimposed image signal voltage, and then obtain the local sub-region A image after time delay integration, thereby achieving the beneficial effect of improving the signal-to-noise ratio.

[0252] In the sampling operation cycle of the TN+1 line period, PIX1, PIX2, PIX3, and PIX4 respectively collect local sub-area image signal voltages and reset signal voltages for the local areas composed of local sub-areas E, D, C, and B, and store the image signal voltages and reset signal voltages after the first stage of amplification in a sampling signal sub-unit and a sampling reset sub-unit, wherein C_05 of PIX1 stores the image signal voltage of P1_E (TN+1), C_10 of PIX2 stores the image signal voltage of P2_D (TN+1), C_15 of PIX3 stores the image signal voltage of P3_C (TN+1), C_20 of PIX4 stores the image signal voltage of P4_B (TN+1), and C_R4 of PIX4 stores the reset signal voltage of P4_B (TN+1).

[0253] In the read operation cycle of the row cycle TN+1, the first-stage amplified image signal voltage and reset signal voltage stored in the sampling signal subunit and the sampling reset subunit are sent to the column signal line through the second amplifying unit 150, wherein C_02 of PIX1 stores the image signal voltage of P1_B (TN-2), C_08 of PIX2 stores the image signal voltage of P2_B (TN-1), C_14 of PIX3 stores the image signal voltage of P3_B (TN), C_20 of PIX4 stores the image signal voltage of P4_B (TN+1), and C_R4 of PIX4 stores the reset signal voltage of P4_B (TN+1). The local sub-region image signal voltage after the first-stage amplification of the four pixels PIX1, PIX2, PIX3, and PIX4 for the four samples of the local sub-region B is sent to the four column signal lines through the second amplification unit and connected to the column amplifier to complete signal superposition, so as to obtain the reset signal voltage of the local sub-region B and the fused and superimposed image signal voltage, and then obtain the local sub-region B image after time delay integration, thereby achieving the beneficial effect of improving the signal-to-noise ratio.

[0254] In the sampling operation cycle of the TN+2 line period, PIX1, PIX2, PIX3, and PIX4 respectively collect local sub-area image signal voltages and reset signal voltages for the local areas composed of local sub-areas F, E, D, and C, and store the image signal voltages and reset signal voltages after the first stage of amplification in a sampling signal sub-unit and a sampling reset sub-unit, wherein C_01 of PIX1 stores the image signal voltage of P1_F (TN+2), C_06 of PIX2 stores the image signal voltage of P2_E (TN+2), C_11 of PIX3 stores the image signal voltage of P3_D (TN+2), C_16 of PIX4 stores the image signal voltage of P4_C (TN+2), and C_R4 of PIX4 stores the reset signal voltage of P4_C (TN+2).

[0255] In the read operation cycle of the row cycle TN+2, the first-stage amplified image signal voltage and reset signal voltage stored in the sampling signal subunit and the sampling reset subunit are sent to the column signal line through the second amplifying unit 150, wherein C_03 of PIX1 stores the image signal voltage of P1_C(TN-1), C_09 of PIX2 stores the image signal voltage of P2_C(TN), C_15 of PIX3 stores the image signal voltage of P3_C(TN+1), C_16 of PIX4 stores the image signal voltage of P4_C(TN+2), and C_R4 of PIX4 stores the reset signal voltage of P4_C(TN+2). The local sub-region image signal voltage after the first-stage amplification of the four pixels PIX1, PIX2, PIX3, and PIX4 for the four samplings of the local sub-region C is sent to the four column signal lines through the second amplification unit and connected to the column amplifier to complete signal superposition, so as to obtain the reset signal voltage of the local sub-region C and the fused and superimposed image signal voltage, and then obtain the local sub-region C image after time delay integration, thereby achieving the beneficial effect of improving the signal-to-noise ratio.

[0256] In the sampling operation period of the TN+3 line period, PIX1, PIX2, PIX3, and PIX4 respectively collect local sub-area image signal voltages and reset signal voltages for the local areas composed of local sub-areas G, F, E, and D, and store the image signal voltages and reset signal voltages after the first stage of amplification in a sampling signal sub-unit and a sampling reset sub-unit, wherein C_02 of PIX1 stores the image signal voltage of P1_G (TN+3), C_07 of PIX2 stores the image signal voltage of P2_F (TN+3), C_12 of PIX3 stores the image signal voltage of P3_E (TN+3), C_17 of PIX4 stores the image signal voltage of P4_D (TN+3), and C_R4 of PIX4 stores the reset signal voltage of P4_D (TN+3).

[0257] In the read operation cycle of the row cycle TN+3, the first-stage amplified image signal voltage and reset signal voltage stored in the sampling signal subunit and the sampling reset subunit are sent to the column signal line through the second amplifying unit 150, wherein C_04 of PIX1 stores the image signal voltage of P1_D(TN), C_10 of PIX2 stores the image signal voltage of P2_D(TN+1), C_11 of PIX3 stores the image signal voltage of P3_D(TN+2), C_17 of PIX4 stores the image signal voltage of P4_D(TN+3), and C_R4 of PIX4 stores the reset signal voltage of P4_D(TN+3). The local sub-region image signal voltage after the first-stage amplification of the four pixels PIX1, PIX2, PIX3, and PIX4 for four times of sampling of the local sub-region D is sent to the four column signal lines through the second amplification unit and connected to the column amplifier to complete signal superposition, so as to obtain the reset signal voltage of the local sub-region D and the fused and superimposed image signal voltage, and then obtain the local sub-region D image after time delay integration, thereby achieving the beneficial effect of improving the signal-to-noise ratio.

[0258] According to the above method, the corresponding image signal voltage and reset signal voltage can be collected for a local area composed of local sub-areas of the target object in each row period, PIX1, PIX2, PIX3, and PIX4. Further, image analysis and fusion processing are performed for multiple groups of image signal voltages and reset signal voltages respectively to obtain the fused local sub-area image voltage and reset signal voltage corresponding to each local sub-area, and then obtain the local sub-area image after time delay integration. Further, multiple local sub-area images after time delay integration are integrated to obtain the target acquisition image after time delay integration of the target object.

[0259] Reference Figure 6 , according to some embodiments of the present application, the second amplification unit 150 includes a second source follower 154 and a readout reset switch 155;

[0260] The drain of the second source follower 154 is used to connect to the third working voltage;

[0261] The gate of the second source follower 154 is connected to the sampling output terminal 142 as the second receiving terminal 151, and is used to read the image signal voltage and the reset signal voltage after the first stage amplification from the multi-sampling switch capacitor unit 140;

[0262] The drain of the read reset switch 155 is used to connect the reference voltage;

[0263] The gate of the readout reset switch 155 serves as the second control terminal 152 for resetting the connection line between the sampling second receiving terminal 151 and the sampling output terminal 142;

[0264] The source of the read-out reset switch 155 is connected to the connection line between the second receiving terminal 151 and the sampling output terminal 142;

[0265] The source of the second source follower 154 serves as the second output terminal 153 for outputting the image signal voltage and the reset signal voltage after secondary amplification.

[0266] It should be emphasized that, since the gate of the second source follower 154 is connected to the sampling output terminal 142 as the second receiving terminal 151, it is used to read the image signal voltage and reset signal voltage after the first stage amplification from the multi-sampling switch capacitor unit 140, and the source of the read-out reset switch 155 is connected to the connection line between the second receiving terminal 151 and the sampling output terminal 142, for this reason, when the gate of the read-out reset switch 155 is used to reset the connection line between the sampling second receiving terminal and the sampling output terminal, the gate of the read-out reset switch 155 is used to reset the connection line between the sampling second receiving terminal and the sampling output terminal. In this way, the second amplifier unit 150 uses the second receiving terminal 151 to read the image signal voltage and reset signal voltage after the first stage amplification from the multi-sampling switch capacitor unit 140, and then outputs the image signal voltage and reset signal voltage after the second stage amplification from the second output terminal 153.

[0267] It should be emphasized that the photosensitive pixel is the photosensitive unit of the image acquisition device, and the photosensitive pixel array is arranged together to form the photosensitive area of ​​the image acquisition device. In order to analyze and fuse the image signal voltage and the reset signal voltage, it is necessary to first perform a primary amplification and a secondary amplification on the image signal voltage and the reset signal voltage to obtain the secondary amplified image signal voltage and the reset signal voltage, and then output the secondary amplified image signal voltage and the reset signal voltage from the second output terminal 153.

[0268] It should be noted that the photosensitive pixels in the embodiments of the present application may include other types of pixel structures in addition to the structures shown in the drawings of the embodiments of the present application. When applying the embodiments of the present application, the corresponding pixel structures can be selected according to specific application requirements, which are not listed here one by one.

[0269] The image acquisition device provided according to the embodiment of the present application includes: a photosensitive module generated based on the photosensitive pixels of the embodiment of the present application. It should be noted that the photosensitive pixels are the photosensitive units of the image acquisition device, and the pixel arrays are arranged together to form the photosensitive area of ​​the image acquisition device, that is, the photosensitive module of the image acquisition device. Since the image acquisition device of the embodiment of the present application is generated based on photosensitive pixels, and the photosensitive pixels benefit from the multi-sampling switch capacitor unit 140, after receiving the image signal voltage and reset signal voltage after the first stage of amplification, the multi-sampling switch capacitor unit 140 can be controlled to store the image signal voltage and reset signal voltage after the first stage of amplification, and then the image signal voltage and reset signal voltage after the first stage of amplification are selectively read from the multi-sampling switch capacitor unit 140, and the connection line between the reset sampling second receiving terminal 151 and the sampling output terminal 142 is reset, and the second output terminal 153 is used to output the image signal voltage and reset signal voltage after the second stage of amplification.

[0270] The photosensitive pixels are arranged in rows and columns to form a pixel array. A column slice has multiple rows of photosensitive pixels, and each row of pixels corresponds to a local sub-region. Signals are collected from a local region of a target object composed of multiple local sub-regions at multiple time points within a target time interval to obtain the corresponding multiple groups of local regions after primary amplification of image signal voltages and reset signal voltages; wherein the primary amplified image signal voltage and reset signal voltage of each group of local regions include the primary amplified image signal voltage and reset signal voltage of the local sub-region collected by the multi-sampling switch capacitor unit of each row of photosensitive pixels at a time point within the target time interval for each local sub-region; secondary amplification and image signal analysis and fusion processing are performed on the primary amplified image signal voltage and reset signal voltage of the multiple groups of local regions to obtain the fused local sub-region image signal voltage and reset signal voltage corresponding to each local sub-region, and the time-integrated local sub-region image can be obtained by the fused local sub-region image signal voltage and reset signal voltage; multiple time-integrated local sub-region images are integrated and spliced ​​to obtain the time-integrated target acquisition image of the target object. In this way, the multiple capacitor units inside the multi-sampling switch capacitor unit 140 help each row of pixels to sample the photographed object at the corresponding position at the corresponding time, and cyclically select the reading of the image signal voltage and reset signal voltage of the corresponding sampling sub-units of each row at the same position at different times.

[0271] In some embodiments of the present application, the photosensitive module of the image acquisition device may include a plurality of photosensitive pixels. On the photosensitive module of the image acquisition device, the photosensitive pixels are arranged in rows and columns to form a pixel array. In the pixel array, the column signal lines led out from the output end of each photosensitive pixel are connected to form a column bus. The column signal lines are used to output the image signal voltage and reset signal voltage after secondary amplification, and the column bus is used to transmit the integrated image signal voltage and the integrated reset signal voltage. The integrated image signal voltage and the integrated reset signal voltage are obtained by integrating the image signal voltage and the reset signal voltage after secondary amplification output by each column signal line. The output end of the photosensitive pixel may be the second output end 153 of the second amplification unit 150 of each photosensitive pixel.

[0272] Specifically, in the pixel array, the output column signal lines of each photosensitive pixel corresponding to each column slice are connected to form a column bus; wherein the output column signal line is used to output the secondary amplified image signal voltage and reset signal voltage collected by each photosensitive pixel on the same local sub-area at different time points, and the column bus is used to transmit and integrate the secondary amplified image signal voltage and reset signal voltage output by multiple column signal lines.

[0273] It should be pointed out that the column signal line of each photosensitive pixel can be independent, and after the column signal line of each photosensitive pixel outputs the image signal voltage and the reset signal voltage, these image signal voltages and reset signal voltages can be analog added or averaged.

[0274] In some more specific embodiments of the present application, on the photosensitive module of the image acquisition device, the photosensitive pixels can be arranged in rows and columns to form a pixel array. Among them, the column signal line of each pixel can be connected to form a column bus, and the integrated image signal voltage and the integrated reset signal voltage are obtained based on the image signal voltage and reset signal voltage after secondary amplification output by each column signal line. Specifically, the second amplification unit 150 of each row of pixels can be used to directly average the image signal voltage and reset signal voltage after secondary amplification output by each row of photosensitive pixels on the column signal line, and then the averaged image signal voltage and reset signal voltage after secondary amplification are obtained, that is, the integrated image signal voltage and the integrated reset signal voltage are transmitted.

[0275] The layout arrangement of the photosensitive pixels in the photosensitive module includes a matrix layout or a distributed layout.

[0276] Reference Figure 7 According to the image acquisition method S700 provided in the embodiment of the present application, the image acquisition device applied to the embodiment of the present application may include, but is not limited to, the following steps S701 to S703.

[0277] Step S701, the photosensitive pixels are arranged in rows and columns to form a pixel array, wherein a column slice has multiple rows of photosensitive pixels, and each row of pixels corresponds to a local sub-region. Signals are collected from a local region of the target object consisting of multiple local sub-regions at multiple time points within a target time interval to obtain a corresponding multiple groups of local regions after primary amplification of image signal voltages and reset signal voltages; wherein the first-stage amplified image signal voltage and reset signal voltage of each group of local regions include the first-stage amplified image signal voltage and reset signal voltage of the local sub-region collected by the multi-sampling switch capacitor units of each row of photosensitive pixels at a time point within the target time interval for each local sub-region;

[0278] Step S702, performing secondary amplification and image signal analysis fusion processing on the primary amplified image signal voltages and reset signal voltages of the multiple groups of local regions to obtain fused local sub-region image signal voltages and reset signal voltages corresponding to each local sub-region, and the time-integrated local sub-region image can be obtained by the fused local sub-region image signal voltages and reset signal voltages;

[0279] Step S703 , integrating and splicing a plurality of time-integrated local sub-region images to obtain a time-integrated target acquisition image of the target object.

[0280] The working principle of the time delay integration technology is to expose a local sub-area of ​​the photographed object to each row of pixels of a column slice of a linear array sensor with multiple rows of pixels, and the collected image signal voltage and reset signal voltage are divided into multiple rows and recorded row by row. In each row cycle, each row of pixels of the image sensor will record and store the corresponding image signal voltage and reset signal voltage. Then, in the next row cycle, the sensor has a relative movement to the photographed object, and each row of pixels of the image sensor will record and store the corresponding image signal voltage and reset signal voltage until all rows of pixels complete the collection and storage of the image signal voltage and reset signal voltage for a local sub-area of ​​the photographed object, and the time-integrated image of the local sub-area can be obtained through the above multiple sets of image signal voltages and reset signal voltages. For each row cycle, the recording time of each row will be delayed a little, which is called "time delay integration". By delaying the recording time of each row, the time delay integration sensor can integrate the light signal multiple times when the image sensor moves.

[0281] The disadvantages of low integration and high power consumption of charge-coupled devices limit the application of time-delayed integration sensors. Therefore, how to utilize the principle of time-delayed integration to enhance the signal-to-noise ratio of images and improve image quality when acquiring images without using charge-coupled devices has become a problem that needs to be solved urgently in the industry. In this regard, the image acquisition method of steps S701 to S703 of the present application is applied to an image acquisition device, and the image acquisition device includes a photosensitive module generated based on the photosensitive pixels of the embodiment of the present application. Therefore, the embodiment of the present application can utilize multiple integrations to enhance the signal-to-noise ratio of images and improve image quality when acquiring images in a high-speed motion and low-light environment.

[0282] Step S701, the photosensitive pixels are arranged in rows and columns to form a pixel array, wherein a column slice has multiple rows of photosensitive pixels, and each row of pixels corresponds to a local sub-region. Signals are collected from a local region of the target object consisting of multiple local sub-regions at multiple time points within a target time interval to obtain a corresponding multiple groups of local regions after primary amplification of image signal voltages and reset signal voltages; wherein the first-stage amplified image signal voltage and reset signal voltage of each group of local regions include the first-stage amplified image signal voltage and reset signal voltage of the local sub-region collected by the multi-sampling switch capacitor units of each row of photosensitive pixels at a time point within the target time interval for each local sub-region;

[0283] It should be noted that the target time interval is also the time interval corresponding to the multiple acquisition signals. At multiple time points within the target time interval, multiple signals of the target object are acquired based on the photosensitive pixels that constitute the photosensitive module, so that multiple groups of first-stage amplified image signal voltages and reset signal voltages can be obtained.

[0284] According to some embodiments of the present application, the local area includes at least one local sub-area, and the photosensitive pixels of the photosensitive module collect the image signal voltage and reset signal voltage of the target object multiple times at multiple time points within the target time interval to obtain the corresponding multiple groups of first-stage amplified image signal voltage and reset signal voltage, which may include:

[0285] Based on a column slice of the photosensitive pixel array, each pixel in the multiple rows of photosensitive pixels collects signals for a local sub-region of the target object, and obtains a first-stage amplified image signal voltage and a reset signal voltage of the local sub-region corresponding to the local sub-region. Then, the relative position of the multiple rows of photosensitive pixels and the target object is adjusted, and each pixel in the multiple rows of photosensitive pixels collects signals for another local sub-region of the target object, and obtains a first-stage amplified image signal voltage and a reset signal voltage of the local sub-region corresponding to the other local sub-region, until the multiple rows of photosensitive pixels in a column slice complete signal collection for a local sub-region of the local area, and the multiple rows of photosensitive pixels obtain multiple groups of first-stage amplified image signal voltages and reset signal voltages, wherein each photosensitive pixel obtains a first-stage amplified image signal voltage and a reset signal voltage corresponding to the local sub-region at a time point.

[0286] Step S702, performing secondary amplification and image signal analysis fusion processing on the primary amplified image signal voltages and reset signal voltages of the multiple groups of local regions to obtain fused local sub-region image signal voltages and reset signal voltages corresponding to each local sub-region, and the time-integrated local sub-region image can be obtained by the fused local sub-region image signal voltages and reset signal voltages;

[0287] It should be noted that the secondary amplification and image analysis fusion processing is performed on the image signal voltage and reset signal voltage after the primary amplification of multiple groups of local areas, aiming to determine and select the image signal voltage and reset signal voltage after the primary amplification of a local sub-area from each group of image signal voltage and reset signal voltage after the primary amplification, and fuse the image signal voltage and reset signal voltage of the local sub-area after the primary amplification of a local sub-area through the second amplification unit to the column signal line or column bus. It should be understood that since the multiple groups of image signal voltage and reset signal voltage after the primary amplification are collected at multiple time points within the target time interval, the image signal voltage and reset signal voltage of the local sub-area after the primary amplification corresponding to different time points of the same local sub-area can jointly participate in the fusion of the image signal voltage and reset signal voltage of the same local sub-area, thereby obtaining the fused image signal voltage and reset signal voltage, and then obtaining a clearer and more accurate local sub-area image after time integration. It should be pointed out that the signal fusion processing based on the image signal voltage and reset signal voltage collected from the same local sub-area can include, but is not limited to: signal superposition, voltage averaging and other implementation methods.

[0288] Step S703 , integrating and splicing a plurality of time-integrated local sub-region images to obtain a time-integrated target acquisition image of the target object.

[0289] It should be noted that, after obtaining a plurality of time-integrated local sub-region images, the plurality of time-integrated local sub-region images can be integrated to restore the time-integrated target acquisition image of the target object.

[0290] In the embodiment of the present application shown by steps S701 to S703, in a high-speed motion and low-light environment, the time delay integration sensor can use multiple integrations to enhance the signal-to-noise ratio of the image and improve the image quality. By using the photosensitive pixel, image acquisition device and method for implementing time delay integration provided by the embodiment of the present application, the principle of time delay integration can be used to enhance the signal-to-noise ratio of the image and improve the image quality when acquiring the image without using a charge coupled device.

[0291] It should be noted that the image acquisition method S700 provided in the embodiment of the present application, in the above Figure 3D , Figure 4D , Figure 5D And in the corresponding text description, corresponding specific embodiments are given. The specific implementation methods can be found above and will not be repeated.

[0292] It should be understood that the image acquisition method S700 provided in the embodiment of the present application may include, but is not limited to, the specific embodiments listed above.

[0293] The terms "first", "second", "third", "fourth", etc. (if any) in the specification of the present disclosure and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable where appropriate, so that the embodiments of the present disclosure described herein can, for example, be implemented in an order other than those illustrated or described herein. In addition, the terms "comprises" and "comprising" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0294] It should be understood that in the present disclosure, "at least one (item)" means one or more, and "plurality" means two or more. "And / or" is used to describe the association relationship of associated objects, indicating that three relationships may exist. For example, "A and / or B" can mean: only A exists, only B exists, and A and B exist at the same time, where A and B can be singular or plural. The character " / " generally indicates that the objects associated before and after are in an "or" relationship. "At least one of the following" or similar expressions refers to any combination of these items, including any combination of single or plural items. For example, at least one of a, b or c can mean: a, b, c, "a and b", "a and c", "b and c", or "a and b and c", where a, b, c can be single or multiple.

[0295] It should be understood that in the description of the embodiments of the present application, the meaning of multiple (or multiple items) is more than two, greater than, less than, exceed, etc. are understood to not include the number, and above, below, within, etc. are understood to include the number.

[0296] In the several embodiments provided in the present disclosure, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of units is only a logical function division. There may be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be an indirect coupling or communication connection through some interfaces, devices or units, which can be electrical, mechanical or other forms.

[0297] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0298] In addition, each functional unit in each embodiment of the present disclosure may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit.

[0299] It should also be understood that the various implementations provided in the embodiments of the present application can be combined arbitrarily to achieve different technical effects.

[0300] The above is a specific description of the implementation methods of the present disclosure, but the present disclosure is not limited to the above implementation methods. Technical personnel familiar with the art can also make various equivalent modifications or substitutions without violating the spirit of the present disclosure. These equivalent modifications or substitutions are all included in the scope defined by the claims of the present disclosure.

Claims

1. A photosensitive pixel for implementing time delay integration, characterized in that: include: A photosensitive element, used for receiving an external light signal and converting the external light signal into an electrical signal of an image; A global reset switch, the global reset switch is configured at the suspension node, and is used to control the voltage reset of the suspension node to provide a reset signal voltage; a first amplifying unit, comprising a first receiving end, a first control end and a first output end, wherein the first receiving end is connected to the photosensitive element via a suspension node, and is used to receive an electrical signal of the photosensitive element via the suspension node to provide an image signal voltage, and the first control end is used to control the first amplifying unit to perform a first-stage amplification on the image signal voltage and the reset signal voltage of the suspension node; wherein the suspension node is grounded via a first capacitor; A multi-sampling switch capacitor unit, comprising a sampling receiving end and a sampling output end, wherein the sampling receiving end is connected to the first output end and is used to receive the image signal voltage and reset signal voltage after the first stage of amplification, and the multi-sampling switch capacitor unit includes a first number of sampling signal sub-units and a second number of sampling reset sub-units between the sampling receiving end and the sampling output end; wherein the multi-sampling switch capacitor unit is used to store the image signal voltage and reset signal voltage after the first stage of amplification through the sampling signal sub-unit and the sampling reset sub-unit; The second amplifying unit comprises a second receiving end, a second control end and a second output end; wherein the second receiving end is connected to the sampling output end and is used to read the image signal voltage and reset signal voltage after the first stage amplification from the multi-sampling switch capacitor unit, the second control end is used to control the voltage reset of the second receiving end, and the second output end is used to output the image signal voltage and reset signal voltage after the second stage amplification.

2. The photosensitive pixel according to claim 1, characterized in that: The first amplifying unit includes a first source follower and a current control switch; The drain of the first source follower is used to connect to a first operating voltage; The gate of the first source follower is connected to the photosensitive element via a suspension node as the first receiving end; The source of the first source follower is connected to the drain of the current control switch, and the first output terminal is led out from the connection line between the first source follower and the current control switch and connected to the sampling receiving terminal; The gate of the current control switch serves as the first control terminal for controlling the first amplifying unit to perform a first-stage amplification on the image signal voltage and the reset signal voltage, and the source of the current control switch is grounded.

3. The photosensitive pixel according to claim 1, characterized in that: Inside the multi-sampling switch capacitor unit, a first number of the sampling signal sub-units and a second number of the sampling reset sub-units connected in parallel are provided between the sampling receiving end and the sampling output end; The sampling signal subunit is provided with a first sampling switch and a first reading switch connected in series in sequence between the sampling receiving end and the sampling output end; wherein a branch is led out from the connection line between the first sampling switch and the first reading switch, connected to one end of the first sampling capacitor, and the other end of the first sampling capacitor is grounded; The sampling reset subunit is provided with a second sampling switch and a second reading switch connected in series in sequence between the sampling receiving end and the sampling output end; wherein a branch is led out from the connection line between the second sampling switch and the second reading switch, connected to one end of the second sampling capacitor, and the other end of the second sampling capacitor is grounded; The first sampling control interface of the first sampling switch configuration, the first reading control interface of the first reading switch configuration, the second sampling control interface of the second sampling switch configuration, and the second reading control interface of the second reading switch configuration serve as the storage control interface, and are used to control the multi-sampling switch capacitor unit to access and read the image signal voltage and reset signal voltage after the first stage of amplification.

4. The photosensitive pixel according to claim 1, characterized in that: Inside the multi-sampling switch capacitor unit, a first number of the signal sampling sub-units connected in parallel are arranged between the sampling receiving end and the sampling output end, and a second number of the sampling reset sub-units are connected to the sampling output end; The sampling signal subunit comprises a third sampling switch and a third reading switch which are sequentially connected in series at the sampling receiving end and the sampling output end; wherein a branch is led out from the connection line between the third sampling switch and the third reading switch, connected to one end of the third sampling capacitor, and the other end of the third sampling capacitor is grounded; The sampling and resetting subunit has a branch extending from the sampling output end connected to the input end of the first sampling and reading switch, the other end of the first sampling and reading switch is connected to one end of the first sampling and reading capacitor, and the other end of the first sampling and reading capacitor is grounded; The third sampling switch is configured with a third sampling control terminal, the third reading switch is configured with a third reading control terminal, and the first reading switch is configured with a first reading control terminal; wherein the third sampling control terminal, the third reading control terminal and the first reading control terminal serve as the storage control interface, and are used to control the multi-sampling switch capacitor unit to access the image signal voltage and reset signal voltage after the first stage of amplification.

5. The photosensitive pixel according to claim 1, characterized in that: The first amplifying unit comprises a first source follower; The drain of the first source follower is used to connect to a second operating voltage; The gate of the first source follower is connected to the photosensitive element via a suspension node as the first receiving end; The source of the first source follower is connected to the sampling receiving end as the first output end.

6. The photosensitive pixel according to claim 1, characterized in that: A first sampling circuit is provided inside the multi-sampling switch capacitor unit between the sampling receiving end and the sampling output end, a global sampling switch is provided in the first sampling circuit, an input end of the global sampling switch is connected to the sampling receiving end, and an output end of the global sampling switch is connected to the sampling output end; Inside the multi-sampling switch capacitor unit, a first number of sampling signal subunits and a second number of sampling reset subunits are provided between the sampling receiving end and the sampling output end; A first number of the sampling signal subunits are connected to the connection line between the output end of the global sampling switch and the sampling output end through a first side branch port; wherein each of the sampling signal subunits includes a second sampling branch connected to the first side branch port; A second number of the sampling and resetting subunits are connected to the connection line between the first side branch port and the sampling output terminal through a second side branch port; wherein each of the sampling and resetting subunits includes a third sampling and reading branch connected to the second side branch port; The second acquisition and reading branch is connected in series with a second acquisition and reading switch and a second acquisition and reading capacitor in sequence between the first side branch port and the ground; wherein the second acquisition and reading switch is configured with a second acquisition and reading control interface; The third acquisition and reading branch is connected in series with a third acquisition and reading switch and a third acquisition and reading capacitor in sequence between the second side branch port and the ground; wherein the third acquisition and reading switch is configured with a third acquisition and reading control interface; The control end of the global sampling switch, the second sampling and reading control interface and the third sampling and reading control interface serve as the storage control interface, and are used to control the multi-sampling switch capacitor unit to access the image signal voltage and reset signal voltage after the first stage of amplification.

7. The photosensitive pixel according to claim 1, characterized in that: The second amplification unit includes a second source follower and a readout reset switch; The drain of the second source follower is used to connect to a third operating voltage; The gate of the second source follower is connected to the sampling output end as the second receiving end, and is used to read the image signal voltage and reset signal voltage after the first stage of amplification from the multi-sampling switch capacitor unit; The drain of the readout reset switch is used to connect to a reference voltage; The gate of the readout reset switch serves as the second control terminal, and is used to reset the connection line between the sampling second receiving terminal and the sampling output terminal; The source of the readout reset switch is connected to the connection line between the second receiving end and the sampling output end; The source of the second source follower serves as the second output terminal, and is used to output the image signal voltage and reset signal voltage after secondary amplification.

8. The photosensitive pixel according to claim 1, characterized in that: A transmission switch is provided between the photosensitive element and the suspension node, and the transmission switch is used to transmit the image electrical signal collected by the photosensitive element to the suspension node to form an image signal voltage.

9. An image acquisition device for implementing time delay integration, characterized in that: include: A photosensitive module generated based on the photosensitive pixels described in any one of claims 1 to 8.

10. The image acquisition device according to claim 9, characterized in that: The photosensitive module comprises a plurality of photosensitive pixels; wherein the plurality of photosensitive pixels are arranged in rows and columns in the photosensitive module of the image acquisition device to form a pixel array; On each column slice in the pixel array, each row of photosensitive pixels corresponds to a local sub-region, and signal acquisition is performed on a local region of the target object composed of multiple local sub-regions at multiple time points within the target time interval. The column signal line output by each photosensitive pixel is used to output the image signal voltage and reset signal voltage of the local sub-region after secondary amplification acquired by each pixel at different time points for the same local sub-region. The target integrated signal is obtained by fusing the image signal voltage and reset signal voltage after secondary amplification output by multiple column signal lines.

11. The image acquisition device according to claim 9, characterized in that: In the pixel array, the output column signal lines of each photosensitive pixel corresponding to each column slice are connected to form a column bus; wherein each row of photosensitive pixels corresponds to a local sub-region, and signal acquisition is performed on a local region of the target object composed of multiple local sub-regions at multiple time points within a target time interval, and the output column signal line is used to output the secondary amplified image signal voltage and reset signal voltage acquired by each photosensitive pixel on the same local sub-region at different time points, and the column bus is used to transmit and merge the secondary amplified image signal voltage and reset signal voltage output by multiple column signal lines.

12. The image acquisition device according to claim 9, characterized in that: The layout arrangement of the photosensitive pixels in the photosensitive module includes a matrix layout or a distributed layout.

13. An image acquisition method for implementing time delay integration, characterized in that: The image acquisition device as claimed in claim 9 comprises: The photosensitive pixels are arranged in rows and columns to form a pixel array, wherein the photosensitive pixels of a column slice have multiple rows, and each row of pixels corresponds to a local sub-region. Signals are collected from a local region of a target object consisting of multiple local sub-regions at multiple time points within a target time interval to obtain corresponding groups of primary amplified image signal voltages and reset signal voltages of the local regions; wherein the primary amplified image signal voltages and reset signal voltages of each group of the local regions include the primary amplified image signal voltages and reset signal voltages of the local sub-region collected by the multi-sampling switch capacitor units of the photosensitive pixels of each row at a time point within the target time interval for each of the local sub-regions; Performing secondary amplification and image signal analysis and fusion processing on the primary-amplified image signal voltages and reset signal voltages of the plurality of local regions to obtain fused local sub-region image signal voltages and reset signal voltages corresponding to each of the local sub-regions; Determine a time-integrated local sub-region image based on the fused local sub-region image signal voltage and the reset signal voltage; The multiple time-integrated local sub-region images are integrated and spliced ​​to obtain a time-integrated target acquisition image of the target object.

14. The method according to claim 13, characterized in that The method of collecting signals from a local area of ​​the target object consisting of multiple local sub-areas at multiple time points within the target time interval to obtain the first-stage amplified image signal voltages and reset signal voltages of the corresponding multiple groups of local areas includes: Based on a column slice of the photosensitive pixel array, multiple rows of photosensitive pixels perform signal acquisition for a local area of ​​the target object composed of multiple local sub-areas, and respectively obtain the local sub-area image signal voltage and reset signal voltage corresponding to one of the local sub-areas. Then, the relative positions of the multiple rows of photosensitive pixels and the target object are adjusted, and multiple rows of photosensitive pixels perform signal acquisition for another local area of ​​the target object composed of multiple local sub-areas, and respectively obtain the local sub-area image signal voltage and reset signal voltage corresponding to the other local sub-area, until multiple rows of photosensitive pixels in a column slice complete the acquisition of image signal voltage and reset signal voltage for a local sub-area of ​​the local area, and multiple rows of photosensitive pixels obtain multiple groups of local area image signal voltages and reset signal voltages, wherein each photosensitive pixel obtains the image signal voltage and reset signal voltage of the local sub-area corresponding to a time point of the local sub-area.

15. The method according to claim 13, characterized in that The multiple rows of photosensitive pixels of a column slice of the pixel array, the image signal voltage and reset signal voltage after primary amplification of the multiple groups of the local areas are subjected to secondary amplification and image signal analysis and fusion processing to obtain the fused local sub-area image signal voltage and reset signal voltage corresponding to each of the local sub-areas, including: Determine the first-stage amplified image signal voltage and reset signal voltage of the local sub-region collected by each of the photosensitive pixels for the same local sub-region from the first-stage amplified image signal voltage and reset signal voltage of each group of the local regions; Performing signal fusion processing based on the first-stage amplified image signal voltage and reset signal voltage of the local sub-region collected by each row of pixels of the same local sub-region to obtain a fused local sub-region image signal voltage and reset signal voltage corresponding to the local sub-region; After determining the time-integrated local sub-region image based on the fused local sub-region image signal voltage and the reset signal voltage, the method further includes: The time-integrated local sub-region images are integrated and spliced ​​to obtain a target acquisition image corresponding to the time-integrated target object.

Images