Method for correcting driving state of pixel array and correction circuit module

Abstract

The present application provides a method for correcting the driving state of a pixel array and a correction circuit module. The correction method is applied to the readout circuit of a focal plane array detector and includes: sending first-frame bias level adjustment parameters to the pixel array to control the pixels to be in a first driving state, where the first-frame bias level adjustment parameters include the bias level adjustment parameters of each pixel; inputting first-frame image data to the pixel array in the first driving state; sending second-frame bias level adjustment parameters to control the pixels to be in a second driving state, where the second-frame bias level adjustment parameters include the bias level adjustment parameters of each pixel; inputting second-frame image data to the pixel array in the second driving state; obtaining correction parameters for the driving state of the pixel array according to the difference between the correction target value and the second-frame image data and the difference between the second-frame image data and the first-frame image data, where the correction parameters include a plurality of sub-correction parameters, and each sub-correction parameter corresponds to each pixel one by one.

Description

Technical Field

[0001] This application relates to the field of signal imaging technology, and particularly to a method for correcting the driving state of a pixel array and a correction circuit module. Background Art

[0002] A focal plane array detector is a detector that converts signals such as infrared, visible light, and ultraviolet into electrical signals through photoelectric conversion and processes them to obtain a video image of an object. Its core components include a pixel array that receives signal radiation and a readout circuit that collects data generated by the pixels and realizes amplification and output.

[0003] A focal plane array pixel is a sensitive unit with a double-layer or multi-layer microbridge structure and an umbrella structure processed by MEMS technology, and its size can be as small as several micrometers. An array composed of a large number of pixels is called a focal plane array. Currently, with the reduction of pixel size, the scale of the focal plane array has developed from 640×512 to 1024×1024, and can even reach a scale of 2048×2048.

[0004] A readout circuit is a circuit that reads tiny signals, amplifies, filters, converts, and outputs them. In a focal plane array detector, the readout circuit realizes collecting data of each pixel in the array, amplifying it, and performing analog-to-digital conversion and then outputting it. The readout circuit generally includes a pixel bias circuit, a pixel signal conversion circuit, a pixel array control circuit, etc. The pixel bias circuit of the readout circuit realizes connecting the pixel to the circuit and integrating, sampling, and amplifying its current to realize the preliminary acquisition of the signal. The pixel signal conversion circuit of the readout circuit realizes converting the analog signal generated by the pixel bias circuit into a digital signal with a certain accuracy. The pixel array control circuit in the readout circuit, on the one hand, realizes connecting the array pixels to the pixel bias circuit row by row, and on the other hand, realizes orderly outputting the pixel data that has completed analog-to-digital conversion to the outside of the chip.

[0005] To save the area of the processor, and at the same time because the readout circuit adopts the method of integrating pixels row by row, the pixel bias circuit in the readout circuit generally adopts the method of sharing by column-level pixels, that is, each column of pixels shares a pixel bias circuit.

[0006] During the manufacturing process of focal plane array pixels, problems such as uneven doping distribution of materials or processing accuracy often lead to inconsistencies in the size, distribution, thickness, etc. among the array pixels. This further causes differences in the electrical and thermodynamic properties of the array pixels, resulting in the widespread problem of non-uniformity in infrared focal plane array detectors. The existence of non-uniformity makes the response characteristics of the focal plane array pixels to external signals inconsistent. For example, when the detector receives a uniformly distributed signal, pixels with different characteristics will output different values. The non-uniformity problem causes deviations in the detection results of the detector, seriously affecting its imaging quality.

[0007] Focal plane array detectors widely use non-uniformity correction methods to improve the imaging quality of the detectors. Traditional correction methods usually adopt a successive approximation correction strategy. For large array detectors with many bias adjustment gears, the above correction method obtains the optimal correction parameters at a relatively slow speed. Taking a large array detector with 32 bias adjustment gears as an example, it is necessary for the detector to collect at least 16 frames of data before the optimal correction parameters can be obtained. Such a high frame delay will inevitably cause the corresponding detector product to have slow imaging after startup, which is not conducive to enhancing the market competitiveness of the product. Summary of the Invention

[0008] The first aspect of the embodiments of the present application provides a method for correcting the driving state of a pixel array. The correction method is applied to the readout circuit of a focal plane array detector and is used to correct the pixel driving state of the pixel array in the focal plane array detector. The correction method includes:

[0009] Sending a first frame of bias gear adjustment parameters to the pixel array to control each pixel of the pixel array to be in a first driving state, where the first frame of bias gear adjustment parameters includes the bias gear adjustment parameters of each pixel;

[0010] In the first driving state, the pixel array inputs the first frame of image data;

[0011] Sending a second frame of bias gear adjustment parameters to the pixel array to control each pixel of the pixel array to be in a second driving state, where the second frame of bias gear adjustment parameters includes the bias gear adjustment parameters of each pixel;

[0012] In the second driving state, the pixel array inputs the second frame of image data;

[0013] Obtaining the correction parameters of the driving state of the pixel array according to the difference between the correction target value and the second frame of image data, and the difference between the second frame of image data and the first frame of image data, where the correction parameters include a plurality of sub-correction parameters, and each sub-correction parameter corresponds to each pixel of the pixel array.

[0014] In some embodiments, an addition operation is used to compensate a division operation to obtain a correction parameter for the driving state of the pixel array.

[0015] In some embodiments, a circuit is used to perform an operation of C = [A+(B / 2N)] / (B / N) to obtain a correction parameter:

[0016] where A is the difference between a correction target value and second-frame image data, B is the difference between the second-frame image data and the first-frame image data, N is the gear difference between the bias gear corresponding to the second-frame bias gear adjustment parameter and the bias gear corresponding to the first-frame bias gear adjustment parameter, and C is the obtained correction parameter.

[0017] In some embodiments, the bias gear corresponding to the second-frame bias gear adjustment parameter is adjacent to the bias gear corresponding to the first-frame bias gear adjustment parameter, N takes a value of 1, and an operation of C = (A + B / 2) / B is performed to obtain a correction parameter.

[0018] In some embodiments, the correction method further includes:

[0019] Adjusting the second-frame bias gear adjustment parameter by the obtained correction parameter to form an updated bias gear adjustment parameter, where the updated bias gear adjustment parameter includes bias gear adjustment sub-parameters corresponding to each pixel;

[0020] Sending the updated bias gear adjustment parameter to the pixel array to control each pixel of the pixel array to be in a third driving state;

[0021] In the third driving state, the pixel array performs signal detection and obtains one or more subsequent frames of image data.

[0022] A second aspect of the embodiments of the present application provides a correction circuit module, which is applied to a readout circuit of a focal plane array detector and is used to correct the pixel driving state of a pixel array in the focal plane array detector. The correction circuit module includes a driving configuration circuit, a framing control circuit, a parameter operation circuit, a memory, and a central control circuit. The driving configuration circuit is used to refresh the driving configuration parameters of each pixel in the pixel array and control the driving state of the pixel; the framing control circuit is used to receive the data generated by the pixel array and integrate it into an effective DVP timing; the parameter operation circuit is used to complete parameter operations and is used for enabling control of data writing into the memory and reading out from the memory; the central control circuit is used to control the driving configuration circuit and the parameter operation circuit.

[0023] The focal plane array detector has a pixel driving state correction mode. In the pixel driving state correction mode, the central control circuit controls the driving configuration circuit to send a first frame of bias level adjustment parameters to the pixel array to control each pixel of the pixel array to be in a first driving state, where the first frame of bias level adjustment parameters includes the bias level adjustment parameters of each pixel; in the first driving state, the pixel array inputs the first frame of image data; the central control circuit controls the driving configuration circuit to send a second frame of bias level adjustment parameters to the pixel array to control each pixel of the pixel array to be in a second driving state, where the second frame of bias level adjustment parameters includes the bias level adjustment parameters of each pixel; in the second driving state, the pixel array inputs the second frame of image data; under the control of the central control circuit, the parameter operation circuit obtains the correction parameters of the pixel array driving state according to the difference between the correction target value and the second frame of image data, and the difference between the second frame of image data and the first frame of image data, where the correction parameters include a plurality of sub-correction parameters, and each sub-correction parameter corresponds to each pixel of the pixel array one by one.

[0024] In some embodiments, the parameter operation circuit compensates the division operation by addition operation to obtain the correction parameters of the pixel array driving state.

[0025] In some embodiments, the parameter operation circuit obtains the correction parameters by performing the operation of C = [A+(B / 2N)] / (B / N), where A is the difference between the correction target value and the second frame of image data, B is the difference between the second frame of image data and the first frame of image data, N is the level difference between the bias level corresponding to the second frame of bias level adjustment parameters and the bias level corresponding to the first frame of bias level adjustment parameters, and C is the obtained correction parameter.

[0026] In some embodiments, the bias level corresponding to the second frame of bias level adjustment parameters is adjacent to the bias level corresponding to the first frame of bias level adjustment parameters, and the value of N is 1. The correction parameters are obtained by performing the operation of C = (A + B / 2) / B.

[0027] In some embodiments, the parameter operation circuit forms updated bias level adjustment parameters according to the obtained correction parameters and the second frame of bias level adjustment parameters, where the updated bias level adjustment parameters include bias level adjustment sub-parameters corresponding to each pixel; the central control circuit controls the driving configuration circuit to send the updated bias level adjustment parameters to the pixel array to control each pixel of the pixel array to be in a third driving state; in the third driving state, the pixel array inputs the subsequent one or more frames of image data.

[0028] In some embodiments, in the pixel driving state correction mode, the central control circuit further controls the parameter operation circuit to write the first frame of image data into the memory.

[0029] In some embodiments, in the pixel driving state correction mode, the central control circuit further controls the parameter operation circuit to write the second frame of image data into the memory.

[0030] In some embodiments, the correction circuit module is integrated in the readout circuit.

[0031] It should be understood that the above general description and the following detailed description are only exemplary and explanatory, and cannot limit this application. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The drawings herein are incorporated into the specification and form a part of the specification, showing embodiments consistent with this application, and are used together with the specification to explain the principles of this application.

[0033] Figure 1 It is a schematic flowchart of a method for correcting the driving state of a pixel array provided by an embodiment of this application;

[0034] Figure 2 It is a schematic diagram of a module of a correction circuit module provided by an embodiment of this application. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0035] Here, the technical solutions in the embodiments (or "embodiment modes") of this application will be clearly and completely described in conjunction with the drawings. When the following description involves the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements.

[0036] If there are terms related to directional indications or positional relationships in the embodiments of this application (such as up, down, left, right, front, back, inside, outside, top, bottom, center, vertical, horizontal, longitudinal, transverse, length, width, counterclockwise, clockwise, axial, radial, circumferential, etc.), such terms are only used to explain the relative positional relationships and movement conditions between components in a specific posture; if the specific posture changes, the directional indication or positional relationship will also change accordingly. In addition, the terms "first", "second", etc. involved in the embodiments of this application are only for the purpose of convenient description and cannot be understood as indicating or implying relative importance.

[0037] As described above, the successive approximation calibration strategy adopted by the traditional calibration method results in a slow speed of obtaining the optimal calibration parameters. To improve the above defects, an embodiment of the present application provides a calibration method for the driving state of the pixel array, which can be applied to the readout circuit of the focal plane array detector and is used to calibrate the pixel driving state of the pixel array in the focal plane array detector, such as Figure 1 shown, the calibration method includes:

[0038] Step S10: Send the first-frame bias gear adjustment parameter to the pixel array to control each pixel of the pixel array to be in the first driving state, where the first-frame bias gear adjustment parameter includes the bias gear adjustment parameter of each pixel;

[0039] Step S20: When the first-frame image data is input to the pixel array in the first driving state, store the first-frame image data;

[0040] Step S30: Send the second-frame bias gear adjustment parameter to the pixel array to control the pixels of the pixel array to be in the second driving state, where the second-frame bias gear adjustment parameter includes the bias gear adjustment parameter of each pixel;

[0041] Step S40: When the second-frame image data is input to the pixel array in the second driving state, store the second-frame image data;

[0042] Step S50: Obtain the calibration parameter of the driving state of the pixel array according to the difference between the calibration target value and the second-frame image data, and the difference between the second-frame image data and the first-frame image data, where the calibration parameter includes a plurality of sub-calibration parameters, and each sub-calibration parameter corresponds to each pixel of the pixel array one by one.

[0043] Using the above calibration method in the above embodiment, large-array detectors with multiple bias adjustment gears can all obtain the optimal calibration parameters within two frames of time, and thus can meet the requirement of high-efficiency and fast image output after the detector is powered on.

[0044] In the above embodiments, the bias level adjustment parameters of each pixel included in the first frame bias level adjustment parameters may all be the same or may not be completely the same. That is, in the first frame bias level adjustment parameters, the bias level adjustment parameters of each pixel can be set independently of each other. Taking an array detector with 32 bias adjustment levels (the 32 levels included are the 0th level, the 1st level, the 2nd level, ……, the 29th level, the 30th level, and the 31st level) as an example, each pixel can be set to a different level or can be set to the same level. In the first frame bias level adjustment parameters, the set values of the bias level adjustment parameters of each pixel do not affect or hardly affect the final calibration result. In one embodiment, the bias level adjustment parameters of each pixel can all be set to the 0th level.

[0045] In the above embodiments, the first frame of image data includes the gray scale values of each pixel. That is, in the first frame of image data input from the pixel array to the readout circuit, the gray scale values of each pixel in the first driving state are included.

[0046] In the above embodiments, the bias level adjustment parameters of each pixel included in the second frame bias level adjustment parameters may all be the same or may not be completely the same. That is, in the second frame bias level adjustment parameters, the bias level adjustment parameters of each pixel can be set independently of each other. Taking an array detector with 32 bias adjustment levels (the 32 levels included are the 0th level, the 1st level, the 2nd level, ……, the 29th level, the 30th level, and the 31st level) as an example, in the second frame bias level adjustment parameters, each pixel can be set to a different level or can be set to the same level. Similarly, in the second frame bias level adjustment parameters, the set values of the bias level adjustment parameters of each pixel do not affect or hardly affect the final calibration result. In one embodiment, in the second frame bias level adjustment parameters, the bias level adjustment parameters of each pixel can all be set to the 1st level or all be set to the 2nd level.

[0047] In the above embodiments, the second frame of image data includes the gray scale values of each pixel. That is, in the second frame of image data input from the pixel array to the readout circuit, the gray scale values of each pixel in the second driving state are included.

[0048] In the above embodiments, the calibration target value corresponds to the gray scale value of the image, which can be set or selected according to user requirements. For example, it can be 8000. Generally speaking, for each pixel in the pixel array, their calibration target values are usually the same. For example, they can all be 8000. The "difference between the calibration target value and the second frame of image data" mentioned in the text refers to the difference between the calibration target value and the gray scale value corresponding to the second frame of image. For each pixel, the difference between the calibration target value and the gray scale value corresponding to its second frame of image may not be equal. The "difference between the second frame of image data and the first frame of image data" mentioned in the text refers to the difference between the gray scale value corresponding to the second frame of image and the gray scale value corresponding to the first frame of image. For each pixel, the difference between the gray scale value corresponding to its second frame of image and the gray scale value corresponding to its first frame of image may not be equal.

[0049] In some embodiments, the division operation can be compensated by an addition operation to obtain the calibration parameter. For example, a characteristic circuit of C = [A+(B / 2N)] / (B / N) can be designed to ensure the accuracy of the calibration parameter. Where A is the difference between the calibration target value and the second frame of image data, B is the difference between the second frame of image data and the first frame of image data, N is the gear difference between the bias gear corresponding to the second frame of bias gear adjustment parameter and the bias gear corresponding to the first frame of bias gear adjustment parameter, and C is the obtained calibration parameter.

[0050] When the bias gear corresponding to the second frame of bias gear adjustment parameter is adjacent to the bias gear corresponding to the first frame of bias gear adjustment parameter, the value of N can be 1 or -1. For example, when the first frame of bias gear adjustment parameter of a pixel is set to the 0th gear and the second frame of bias gear adjustment parameter of the pixel is set to the 1st gear at the same time, the corresponding gear difference N is equal to 1. Correspondingly, the operation of C = (A + B / 2) / B is executed to obtain the calibration parameter. When the value of N is 1, the amount of calculation can be reduced and the calibration speed can be further increased. Another example is that when the first frame of bias gear adjustment parameter of a pixel is set to the 31st gear and the second frame of bias gear adjustment parameter of the pixel is set to the 30th gear at the same time, the corresponding gear difference N is equal to -1. When the value of N is -1, the amount of calculation can be reduced and the calibration speed can be further increased.

[0051] When the offset gear corresponding to the second-frame offset gear adjustment parameter is not adjacent to the offset gear corresponding to the first-frame offset gear adjustment parameter, the value of N is an integer greater than 1 or less than -1. For example, when the first-frame offset gear adjustment parameter of a pixel is set to the 0th gear, and the second-frame offset gear adjustment parameter of the same pixel is set to the 2nd gear, the corresponding gear difference N is equal to 2. Correspondingly, the correction parameter is obtained by performing the operation of C = (A + B / 4) / (B / 2). Another example is when the first-frame offset gear adjustment parameter of a pixel is set to the 31st gear, and the second-frame offset gear adjustment parameter of the same pixel is set to the 29th gear, the corresponding gear difference N is equal to -2.

[0052] In the above embodiment, the correction parameter C corresponds to the gear value that each pixel needs to be further adjusted based on the second-frame offset gear adjustment parameter. For a pixel, when the calculated C value is equal to 0, the second-frame offset gear where the pixel is currently located is its optimal offset gear; when the calculated C value is equal to 1, the second-frame offset gear of the pixel needs to be adjusted upward by one gear; when the calculated C value is equal to N, the second-frame offset gear of the pixel needs to be adjusted upward by N gears. For example, when the first-frame offset gear adjustment parameter of a pixel is set to the 0th gear, and the second-frame offset gear adjustment parameter of the pixel is set to the 2nd gear, and the correction parameter C obtained according to the above correction method is equal to 3, then it is necessary to adjust upward by 3 gears based on the 2nd gear, that is, the 5th gear is the optimal offset gear of the pixel. Another example is when the first-frame offset gear adjustment parameter of a pixel is set to the 0th gear, and the second-frame offset gear adjustment parameter of the pixel is set to the 5th gear, and the correction parameter C obtained according to the above correction method is equal to -2, then it is necessary to adjust downward by 2 gears based on the 5th gear, that is, the 3rd gear is the optimal offset gear of the pixel.

[0053] In the above embodiment, the calculated correction parameter C may be a non-integer. In this case, it can be rounded according to the rounding principle.

[0054] In some embodiments, the correction method may further include:

[0055] Adjusting the second-frame offset gear adjustment parameter by the obtained correction parameter to form an updated offset gear adjustment parameter, where the updated offset gear adjustment parameter includes offset gear adjustment sub-parameters corresponding to each pixel;

[0056] Sending the updated offset gear adjustment parameter to the pixel array to control each pixel of the pixel array to be in the third driving state;

[0057] In the third driving state, the pixel array performs signal detection and obtains subsequent one or more frames of image data.

[0058] Since the bias levels of the respective pixels have been corrected by the corresponding correction parameters, the image data obtained in the third driving state is equal to or close to the correction target value.

[0059] An embodiment of the present application further provides a correction circuit module, which is applied to the readout circuit of a focal plane array detector, as Figure 2 shown, and in combination with Figure 1 when necessary. The correction circuit module is used to correct the pixel driving state of the pixel array. The pixel array is used to receive external signal radiation and can form a focal plane array detector together with the correction circuit module.

[0060] The correction circuit module includes a driving configuration circuit, a framing control circuit, a parameter operation circuit, a memory, and a central control circuit. The driving configuration circuit is used to refresh the driving configuration parameters of each pixel in the pixel array and control the driving state of the pixels; the framing control circuit is used to receive the data generated by the pixel array and integrate it into an effective DVP timing; the parameter operation circuit is used to complete parameter operations and is used for enabling control of data writing into the memory and reading out from the memory; the central control circuit is used to control the driving configuration circuit and the parameter operation circuit;

[0061] The focal plane array detector has a pixel driving state correction mode. In the pixel driving state correction mode, the central control circuit controls the driving configuration circuit to send a first-frame bias level adjustment parameter to the pixel array to control each pixel of the pixel array to be in a first driving state, where the first-frame bias level adjustment parameter includes the bias level adjustment parameters of each pixel; in the first driving state, the pixel array inputs corresponding first-frame image data; the central control circuit controls the driving configuration circuit to send a second-frame bias level adjustment parameter to the pixel array to control each pixel of the pixel array to be in a second driving state, where the second-frame bias level adjustment parameter includes the bias level adjustment parameters of each pixel; in the second driving state, the pixel array inputs corresponding second-frame image data; under the control of the central control circuit, the parameter operation circuit obtains the correction parameters of the pixel array driving state according to the difference between the correction target value and the second-frame image data, and the difference between the second-frame image data and the first-frame image data, where the correction parameters include a plurality of sub-correction parameters, and each sub-correction parameter corresponds to each pixel of the pixel array.

[0062] In the detector in the above embodiments, regardless of the number of bias adjustment gears, it can obtain the optimal calibration parameters within two frames of time, and thus can meet the requirement of high-efficiency and fast image output after the detector is powered on.

[0063] In the above embodiments, the bias adjustment parameters of each pixel included in the first-frame bias adjustment parameters may all be the same or may not all be the same. That is, in the first-frame bias adjustment parameters, the bias adjustment parameters of each pixel can be set independently of each other. Taking an array detector with 32 bias adjustment gears (the 32 gears included are the 0th gear, the 1st gear, the 2nd gear, ……, the 29th gear, the 30th gear, and the 31st gear) as an example, each pixel can be set to different gears or can be set to the same gear. In the first-frame bias adjustment parameters, the set values of the bias adjustment parameters of each pixel do not affect or hardly affect the final calibration result. In one embodiment, the bias adjustment parameters of each pixel can all be set to the 0th gear.

[0064] In the above embodiments, the first-frame image data includes the gray-scale values of each pixel. That is, in the first-frame image data input from the pixel array to the readout circuit, the gray-scale values of each pixel in the first driving state are included.

[0065] In the above embodiments, the bias adjustment parameters of each pixel included in the second-frame bias adjustment parameters may all be the same or may not all be the same. That is, in the second-frame bias adjustment parameters, the bias adjustment parameters of each pixel can be set independently of each other. Taking an array detector with 32 bias adjustment gears (the 32 gears included are the 0th gear, the 1st gear, the 2nd gear, ……, the 29th gear, the 30th gear, and the 31st gear) as an example, in the second-frame bias adjustment parameters, each pixel can be set to different gears or can be set to the same gear. Similarly, in the second-frame bias adjustment parameters, the set values of the bias adjustment parameters of each pixel do not affect or hardly affect the final calibration result. In one embodiment, in the second-frame bias adjustment parameters, the bias adjustment parameters of each pixel can all be set to the 1st gear or all be set to the 2nd gear.

[0066] In the above embodiments, the second-frame image data includes the gray-scale values of each pixel. That is, in the second-frame image data input from the pixel array to the readout circuit, the gray-scale values of each pixel in the second driving state are included.

[0067] In the above embodiments, the calibration target value corresponds to the gray scale value of the image, which can be set or selected according to user requirements. For example, it can be 8000. Generally speaking, for each pixel in the pixel array, their calibration target values are usually the same. For example, they can all be 8000. The "difference between the calibration target value and the second-frame image data" mentioned in the text refers to the difference between the calibration target value and the gray scale value corresponding to the second-frame image. For each pixel, the difference between the calibration target value and the gray scale value corresponding to its second-frame image may not be equal. The "difference between the second-frame image data and the first-frame image data" mentioned in the text refers to the difference between the gray scale value corresponding to the second-frame image and the gray scale value corresponding to the first-frame image. For each pixel, the difference between the gray scale value corresponding to its second-frame image and the gray scale value corresponding to its first-frame image may not be equal.

[0068] In some embodiments, the parameter operation circuit compensates the division operation by addition operation to obtain the calibration parameter of the driving state of the pixel array. For example, the parameter operation circuit realizes the acquisition of the optimal calibration parameter by executing the operation of C = [A+(B / 2N)] / (B / N) to ensure the accuracy of the calibration parameter.

[0069] Wherein, A is the difference between the calibration target value and the second-frame image data, B is the difference between the second-frame image data and the first-frame image data, N is the gear difference between the bias gear corresponding to the second-frame bias gear adjustment parameter and the bias gear corresponding to the first-frame bias gear adjustment parameter, and C is the obtained calibration parameter.

[0070] When the bias gear corresponding to the second-frame bias gear adjustment parameter is adjacent to the bias gear corresponding to the first-frame bias gear adjustment parameter, the value of N can be 1 or -1. For example, when the first-frame bias gear adjustment parameter of a pixel is set to the 0th gear and the second-frame bias gear adjustment parameter of this pixel is set to the 1st gear at the same time, then the corresponding gear difference N is equal to 1. Correspondingly, the acquisition of the calibration parameter is realized by executing the operation of C = (A + B / 2) / B. When the value of N is 1, the amount of calculation can be reduced and the calibration speed can be further accelerated. Another example is that when the first-frame bias gear adjustment parameter of a pixel is set to the 31st gear and the second-frame bias gear adjustment parameter of this pixel is set to the 30th gear at the same time, then the corresponding gear difference N is equal to -1. When the value of N is -1, the amount of calculation can be reduced and the calibration speed can be further accelerated.

[0071] When the offset gear corresponding to the second-frame offset gear adjustment parameter is not adjacent to the offset gear corresponding to the first-frame offset gear adjustment parameter, the value of N is an integer greater than 1 or less than -1. For example, when the first-frame offset gear adjustment parameter of a pixel is set to gear 0, and at the same time the second-frame offset gear adjustment parameter of this pixel is set to gear 2, then the corresponding gear difference N is equal to 2. Another example is when the first-frame offset gear adjustment parameter of a pixel is set to gear 31, and at the same time the second-frame offset gear adjustment parameter of this pixel is set to gear 29, then the corresponding gear difference N is equal to -2.

[0072] In the above embodiment, the correction parameter C corresponds to the gear value that each pixel needs to be further adjusted based on the second-frame offset gear adjustment parameter. For a pixel, when the calculated C value is equal to 0, the current second-frame offset gear of this pixel is its optimal offset gear; when the calculated C value is equal to 1, the current second-frame offset gear of this pixel needs to be adjusted upward by one gear; when the calculated C value is equal to N, the current second-frame offset gear of this pixel needs to be adjusted upward by N gears. For example, when the first-frame offset gear adjustment parameter of a pixel is set to gear 0, and the second-frame offset gear adjustment parameter of this pixel is set to gear 2, and the correction parameter C obtained according to the above correction method is equal to 3, then it is necessary to adjust upward by 3 gears based on gear 2, that is, gear 5 is the optimal offset gear of this pixel. Another example is when the first-frame offset gear adjustment parameter of a pixel is set to gear 0, and the second-frame offset gear adjustment parameter of this pixel is set to gear 5, and the correction parameter C obtained according to the above correction method is equal to -2, then it is necessary to adjust downward by 2 gears based on gear 5, that is, gear 3 is the optimal offset gear of this pixel.

[0073] In the above embodiment, the calculated correction parameter C may be a non-integer. In this case, it can be rounded according to the rounding principle.

[0074] In some embodiments, the parameter operation circuit forms updated offset gear adjustment parameters according to the obtained correction parameter and the second-frame offset gear adjustment parameter, where the updated offset gear adjustment parameters include offset gear adjustment sub-parameters corresponding to each pixel; the central control circuit controls the drive configuration circuit to send the updated offset gear adjustment parameters to the pixel array to control each pixel of the pixel array to be in the third drive state; in the third drive state, the pixel array performs signal detection and obtains subsequent one or more frames of image data.

[0075] Since the offset gears of each pixel have been corrected by the corresponding correction parameters, the image data obtained in the third drive state is equal to or close to the correction target value.

[0076] In some embodiments, in the pixel driving state correction mode, the central control circuit further controls the parameter operation circuit to write the first frame of image data into the memory.

[0077] In some embodiments, in the pixel driving state correction mode, the central control circuit further controls the parameter operation circuit to write the second frame of image data into the memory.

[0078] In some embodiments, the focal plane array detector further includes a readout circuit for collecting data generated by pixels and realizing amplified output;

[0079] The correction circuit module is integrated in the readout circuit.

[0080] It should be noted that the technical solutions or technical features described in the above embodiments can be combined or supplemented with each other without conflict. The scope of protection of this application is not limited to the precise structures described in the above embodiments and shown in the drawings; all modifications, equivalent replacements, improvements, etc. made within the spirit and principle of this application shall be included within the scope of protection of this application.

Claims

1. A method for correcting the driving state of a pixel array, characterized in that The calibration method is applied to the readout circuit of a focal plane array detector for calibrating the pixel driving states of the pixel array in the focal plane array detector. The calibration method includes: Sending a first-frame bias level adjustment parameter to the pixel array to control each pixel of the pixel array to be in a first driving state, where the first-frame bias level adjustment parameter includes the bias level adjustment parameter for each pixel; With the pixel array in the first driving state, the pixel array inputs first-frame image data; Sending a second-frame bias level adjustment parameter to the pixel array to control each pixel of the pixel array to be in a second driving state, where the second-frame bias level adjustment parameter includes the bias level adjustment parameter for each pixel; With the pixel array in the second driving state, the pixel array inputs second-frame image data; Obtaining calibration parameters for the driving state of the pixel array according to the difference between the calibration target value and the second-frame image data, and the difference between the second-frame image data and the first-frame image data, where the calibration parameters include a plurality of sub-calibration parameters, and each sub-calibration parameter corresponds one-to-one to each pixel of the pixel array.

2. The calibration method according to claim 1, characterized in that, Compensating the division operation by using an addition operation to obtain the calibration parameters for the driving state of the pixel array.

3. The calibration method according to claim 2, wherein Performing an operation of C = [A+(B / 2N)] / (B / N) by using a circuit to achieve the acquisition of calibration parameters: where A is the difference between the calibration target value and the second-frame image data, B is the difference between the second-frame image data and the first-frame image data, N is the level difference between the bias level corresponding to the second-frame bias level adjustment parameter and the bias level corresponding to the first-frame bias level adjustment parameter, and C is the obtained calibration parameter.

4. The calibration method according to claim 3, characterized in that The bias level corresponding to the second-frame bias level adjustment parameter is adjacent to the bias level corresponding to the first-frame bias level adjustment parameter, and N takes a value of 1. The acquisition of calibration parameters is achieved by performing an operation of C = (A + B / 2) / B.

5. The calibration method according to claim 1, wherein, The calibration method further includes: Adjusting the second-frame bias level adjustment parameter by using the obtained calibration parameters to form updated bias level adjustment parameters, where the updated bias level adjustment parameters include bias level adjustment sub-parameters corresponding to each pixel; Sending the updated bias level adjustment parameters to the pixel array to control each pixel of the pixel array to be in a third driving state; With the pixel array in the third driving state, the pixel array performs signal detection and obtains one or more subsequent frames of image data.

6. A calibration circuit module is applied to the readout circuit of a focal plane array detector and is used to calibrate the pixel driving state of the pixel array in the focal plane array detector. It is characterized in that The calibration circuit module includes a driving configuration circuit, a framing control circuit, a parameter operation circuit, a memory, and a central control circuit. The driving configuration circuit is used to refresh the driving configuration parameters of each pixel in the pixel array and control the driving state of the pixel; the framing control circuit is used to receive the data generated by the pixel array and integrate it into a valid DVP timing; the parameter operation circuit is used to complete parameter operations and for the enable control of data writing into the memory and reading out from the memory; the central control circuit is used to control the driving configuration circuit and the parameter operation circuit; The focal plane array detector has a pixel drive state correction mode. In the pixel drive state correction mode, the central control circuit controls the drive configuration circuit to send a first frame of bias level adjustment parameters to the pixel array to control each pixel of the pixel array to be in a first drive state, where the first frame of bias level adjustment parameters includes the bias level adjustment parameters of each pixel; in the first drive state, the pixel array inputs first frame of image data; the central control circuit controls the drive configuration circuit to send a second frame of bias level adjustment parameters to the pixel array to control each pixel of the pixel array to be in a second drive state, where the second frame of bias level adjustment parameters includes the bias level adjustment parameters of each pixel; in the second drive state, the pixel array inputs second frame of image data; under the control of the central control circuit, the parameter operation circuit obtains the correction parameters of the pixel array drive state according to the difference between the correction target value and the second frame of image data, and the difference between the second frame of image data and the first frame of image data, where the correction parameters include a plurality of sub-correction parameters, and each sub-correction parameter corresponds to each pixel of the pixel array one by one.

7. The calibration circuit module according to claim 6, wherein The parameter operation circuit compensates the division operation by addition operation to obtain the correction parameters of the pixel array drive state.

8. The calibration circuit module according to claim 7, wherein The parameter operation circuit obtains the correction parameters by performing the operation of C = [A+(B / 2N)] / (B / N), where A is the difference between the correction target value and the second frame of image data, B is the difference between the second frame of image data and the first frame of image data, N is the level difference between the bias level corresponding to the second frame of bias level adjustment parameters and the bias level corresponding to the first frame of bias level adjustment parameters, and C is the obtained correction parameters.

9. The calibration circuit module according to claim 8, wherein, The bias level corresponding to the second frame of bias level adjustment parameters is adjacent to the bias level corresponding to the first frame of bias level adjustment parameters, and the value of N is 1. The correction parameters are obtained by performing the operation of C = (A + B / 2) / B.

10. The calibration circuit module according to claim 6, characterized in that, The parameter operation circuit forms updated bias level adjustment parameters according to the obtained correction parameters and the second frame of bias level adjustment parameters, where the updated bias level adjustment parameters include bias level adjustment sub-parameters corresponding to each pixel; the central control circuit controls the drive configuration circuit to send the updated bias level adjustment parameters to the pixel array to control each pixel of the pixel array to be in a third drive state; in the third drive state, the pixel array inputs the subsequent one frame or multiple frames of image data.

11. The calibration circuit module according to claim 6, wherein In the pixel drive state correction mode, the central control circuit also controls the parameter operation circuit to write the first frame of image data into the memory.

12. The calibration circuit module according to claim 6, wherein In the pixel drive state correction mode, the central control circuit also controls the parameter operation circuit to write the second frame of image data into the memory.

13. The calibration circuit module according to claim 6, wherein, The correction circuit module is integrated in the readout circuit.

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