Method and detector capable of improving anti-interference performance of image

Abstract

The invention relates to the technical field of X-ray detectors, and provides a method capable of improving the anti-interference performance of an image and a detector. The interference detection circuit is additionally arranged in the detector, so that the interference response coefficient of the X-ray detector to the external interference intensity is obtained in the interference correction mode. In the normal acquisition mode, the interference response coefficient obtained in the interference correction mode, the detector signal response data in the normal acquisition mode and the interference intensity of the interference detection circuit are utilized to obtain an effective detector image, so that low and controllable hardware cost increase is realized; the image performance which is more reliable, more stable and better in effect is obtained under the interference scene, so that the interference fringes are greatly weakened or disappeared, and the image quality is remarkably improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of X-ray detectors, in particular to a method for improving image anti-interference performance and a detector. BACKGROUND

[0002] X-ray detectors are widely used in medical, industrial, security and other fields. In actual application scenarios, different external interferences may exist, such as electrostatic discharge, power fluctuation, power surge, power frequency magnetic field interference, radio frequency conduction or radiation interference, etc. The X-ray flat panel detector adopts a rolling shutter mode, and the scanning of the entire pixel array is completed by reading out row by row, and the same row of pixels maintains the same reading time. Therefore, when external interference occurs, random horizontal stripes usually appear on the output image of the X-ray detector.

[0003] For such interference problems, the traditional X-ray detector usually increases different shielding, filtering or changes the grounding loop in the X-ray detector hardware for different types of interference, but since external interference is usually common mode interference and the types of interference are numerous, the transmission path is difficult to estimate, and different interferences may even show completely opposite effects under the same modification measure, so it is difficult to completely solve such problems based on hardware design.

[0004] Some X-ray detector manufacturers also propose to use a specific algorithm to subtract the interference horizontal stripes in the image based on the difference between the interference horizontal stripes and the normal image, but since the interference horizontal stripes have different characteristics under different types, different intensities and different spatial positions, the effect of such method is usually difficult to guarantee, and in some interference scenarios, it may even cause significant deterioration of other performance. SUMMARY

[0005] To solve the problem of existing X-ray detector output image with rolling stripes in external interference scenarios, the present application provides a method for improving image anti-interference performance and a detector, which can achieve more reliable, stable and optimal image performance in interference scenarios.

[0006] To achieve the above purpose, the present application adopts the following technical solutions.

[0007] First, on the one hand, the present application provides a method for improving image anti-interference performance, which comprises: in the normal acquisition mode of the detector, the readout circuit reads the signal response data S of the pixel array row by row; at the same time, the interference detection circuit detects and outputs the interference intensity data R; calculate the effective signal response data V, the calculation formula is as follows: V=S-(R·K), K=S C / R C , R C , where K is the interference response coefficient, S CThe interference detection circuit detects the corrected interference intensity data; for the same row of pixels, the readout circuit reads the signal response data S synchronously with the interference detection circuit detecting the interference intensity data R.

[0008] In some embodiments of the present application, the method adopts overall correction, specifically including: the readout circuit reads the signal response data of all pixels of the pixel array row by row to obtain a matrix {S （m）(n)} as the signal response data S; while the readout circuit reads the signal response data of a row of the pixel array, the interference detection circuit detects the row interference intensity data corresponding to the row, and traverses all rows to obtain a matrix {R (m)} of M*1 size as the interference intensity data R, where 1≤m≤M, 1≤n≤N, and M and N are respectively the number of rows and columns of the pixel array of the detector.

[0009] In some embodiments of the present application, the method also adopts row-by-row correction, specifically including: in the normal acquisition mode of the detector, the readout circuit reads the signal response data of the mth row of pixels to obtain a matrix {S m（n）} as the signal response data S m of the mth row; at the same time, the interference detection circuit detects the row interference intensity data R m corresponding to the mth row, where 1≤m≤M, 1≤n≤N, and M and N are respectively the number of rows and columns of the pixel array of the detector; the effective signal response data V m of the mth row is calculated by the formula V m =S m - (R m ·K); and all rows of the pixel array of the detector are traversed to obtain a matrix {V （m）(n)} of all pixels as the effective signal response data V.

[0010] In some embodiments of the present application, the interference response coefficient K is obtained in a first interference correction mode without X-ray irradiation, and the method for obtaining the interference response coefficient K includes: providing interference to the detector, the interference including at least one of electrostatic discharge, power supply fluctuation, power supply surge, power frequency magnetic field interference, radio frequency conduction, and radiation interference; the readout circuit reads the response data matrix {C （m）(n)} of all pixels of the pixel array row by row as S C ; while the readout circuit reads the response data of a row of the pixel array, the interference detection circuit detects the row interference intensity data corresponding to the row, and traverses all rows to obtain a matrix {C (m)} of M*1 size as R C , where 1≤m≤M, 1≤n≤N, and M and N are respectively the number of rows and columns of the pixel array of the detector; and the interference response coefficient K is calculated by K=S C / RC Calculate K.

[0011] Furthermore, as another optional technical solution, the interference response coefficient K is obtained in a first interference correction mode, wherein there is no X-ray irradiation in the first interference correction mode. The method for obtaining the interference response coefficient K includes: providing interference to the detector, wherein the interference includes at least one of electrostatic discharge, power supply fluctuation, power supply surge, power frequency magnetic field interference, radio frequency conduction, and radiation interference; a readout circuit reads the response data of the pixels in the mth row of the pixel array to obtain the matrix {C m(n)}, as the response data S of the mth row Cm At the same time, the interference detection circuit detects the row interference intensity data R corresponding to the mth row Cm , where 1≤m≤M, 1≤n≤N, M and N are the number of rows and columns of the detector pixel array respectively; through K m =S Cm / R Cm Calculate the interference response coefficient K of the mth row m ; Traverse all rows of the detector pixel array and obtain the interference response coefficient matrix {K （m）(n)}, as the interference response coefficient K.

[0012] Furthermore, the interference response coefficient K is obtained in the second interference correction mode, and the method for obtaining the interference response coefficient K includes: providing interference to the detector, wherein the interference includes at least one of electrostatic discharge, power supply fluctuation, power supply surge, power frequency magnetic field interference, radio frequency conduction, and radiation interference; turning on the X-ray, and the detector obtains the grayscale value image P1 of the calibration sample in the interference environment; in the process of the detector obtaining the grayscale value image P1 of the calibration sample in the interference environment, the detector readout circuit reads the response data of a certain row of pixel arrays, and the interference detection circuit detects the row interference intensity data corresponding to the row, traverses all rows, and obtains the matrix {C (m)}, as R C , where 1≤m≤M, 1≤n≤N, M and N are the number of rows and columns of the detector pixel array respectively; obtain the biased dark field grayscale value image P2 of the detector in an interference-free environment; deduct P2 from P1 to obtain the interference response image P3, and each pixel value of the interference response image P3 is the interference response data S of the detector C , wherein the grayscale value image P1 and the grayscale value image P2 are obtained based on the same detector and / or detector parameters; by K=S C / R C Calculate K.

[0013] Furthermore, the biased dark field grayscale value image in the interference-free environment is generated and stored in the X-ray detector at the factory.

[0014] In some embodiments of the present application, the synchronization of the reading of the signal response data S by the readout circuit and the detection of the interference strength data R by the interference detection circuit for the same row of pixels comprises: when the readout circuit starts a row collection, outputting a row collection pulse as a data collection control signal for the interference detection circuit.

[0015] In a second aspect, the present application further provides a detector capable of improving the anti-interference performance of an image, which is used to implement the above method, and comprises an M*N pixel array, a readout circuit, a processor and an interference detection circuit, the readout circuit is electrically connected to the processor and is used to transmit the read data of the pixel array to the processor, the interference detection circuit is electrically connected to the processor and is used to transmit the detected interference data to the processor, and the processor is used to calculate the effective signal response data V.

[0016] Further, the detector further comprises a storage module, and the storage module stores a bias dark field grayscale value image of the detector in a non-interference environment.

[0017] Compared with the prior art, the present application has the following beneficial effects: The present application adds an interference detection circuit in the detector, obtains the interference response coefficient of the X-ray detector to the external interference strength in the interference correction mode, and obtains the effective detector image by using the interference response coefficient obtained in the interference correction mode, the signal response data of the detector in the normal collection mode and the interference strength of the interference detection circuit in the normal collection mode, so that the image performance is more reliable, more stable and has better effect in the interference scene by increasing the hardware cost in a lower and controllable manner, so that the interference stripes are greatly weakened or disappeared, and the image quality is significantly improved.

[0018] In addition, the anti-interference method of the present application is suitable for multiple and various types of interference, such as random interference and fixed frequency interference, which provides a wider use scene for the method and the detector of the present application, and further improves the reliability and image quality of the detector. BRIEF DESCRIPTION OF DRAWINGS

[0019] The accompanying drawings, which are included to provide a further understanding of the present application and are incorporated in and constitute a part of this application, illustrate embodiments of the present application and serve to explain the present application, and do not constitute improper limitations on the present application. In the drawings: Figure 1 is a schematic diagram of the hardware architecture of the detector capable of improving the anti-interference performance of an image of the present application; Figure 2 is a schematic diagram of the method flow of the method capable of improving the anti-interference performance of an image of the present application; Figure 3 is a schematic diagram of the method of obtaining the interference response coefficient K of the present application; Figure 4is another schematic diagram of the method for obtaining the interference response coefficient K of the present application; Figure 5 is another schematic diagram of the method for obtaining the interference response coefficient K of the present application; Figure 6 is a schematic diagram of the overall interference correction of the method for improving the image anti-interference performance of the present application; Figure 7 is a schematic diagram of the row-by-row interference correction of the method for improving the image anti-interference performance of the present application. DETAILED DESCRIPTION

[0020] In the description of the present application, the following terms need to be explained: For the orientation words, if the terms "center", "transverse", "longitudinal", "length", "width", "thickness", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc. are used in the description and claims of the present application, the orientation and position relationship based on the orientation or position relationship shown in the drawings is indicated, which is only for the convenience of describing the present application and simplifying the description, and is not intended to indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and cannot be understood as limiting the specific protection scope of the present application.

[0021] The terms "first", "second", etc. in the description and claims of the present application are used to distinguish similar objects, and do not necessarily describe a specific order or sequence.

[0022] The terms "include" and "have" and any variations thereof in the description and claims of the present application are intended to cover non-exclusive inclusion, for example, a process, method, system, product or device that includes a series of steps or units does not have to be limited to only those steps or units clearly listed, but can include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0023] When an element is referred to as "fixed to" or "provided on" another element, it can be directly on the other element or there can be a middle element. When an element is referred to as "connected to" another element, it can be directly connected to the other element or there can be a middle element. When an element is referred to as "provided with" another element, it can be provided on the surface or inside of the element.

[0024] Unless otherwise explicitly stated, throughout the specification and claims, the term "comprise" or its variants such as "contain" or "include" will be understood to include the stated element or component, without excluding other elements or components.

[0025] In the specification and claims of the present application, the term "electrically connected" can be a circuit connection in physical contact, or a communication connection, which can be a wired communication connection or a wireless communication connection.

[0026] In the application scenario of the X-ray detector, various external interference conditions usually exist, and the X-ray detector contains analog devices, which are usually susceptible to interference, and when the interference occurs, the output image of the X-ray detector shows rolling stripes, which are difficult to correct and can cause the performance of the whole system to decrease.

[0027] The present application takes the external interference as the signal input of the X-ray detector, adds an interference correction mode in the application of the X-ray detector, adds an interference detection circuit in the X-ray detector, and in the interference correction mode, the X-ray detector and the interference detection circuit simultaneously collect the same external interference signal to obtain the interference response coefficient of the X-ray detector to the external interference intensity. In the normal acquisition mode, the interference detection circuit and the X-ray detector also collect at the same time, and at this time, the image output of the X-ray detector corresponds to the sum of the effective signal and the external interference signal in response to the user input. By multiplying the interference response coefficient obtained in the interference correction mode and the interference intensity of the interference detection circuit in the normal acquisition mode, the contribution of the external interference signal part in the image output of the X-ray detector in the normal acquisition mode can be restored, and after deducting this part of the contribution, the X-ray detector image corresponding to the effective signal input by the user is obtained. In order to make the present application clearer and more understandable, the technical solutions in the embodiments of the present application will be described clearly and completely in conjunction with the drawings. Obviously, the described embodiments are only a part of the embodiments of the present application, not all. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0028] Firstly, the present application provides a detector capable of improving image anti-interference performance, and the hardware architecture thereof is as shown in the figure Figure 1 The detector comprises an M*N pixel array, a readout circuit, a signal processing circuit, a processor and an interference detection circuit. The readout circuit is electrically connected to the processor and is used to transmit the read data of the pixel array to the processor. The interference detection circuit is electrically connected to the processor and is used to transmit the detected interference data to the processor. The processor is used to calculate effective signal response data V. Wherein Figure 1 SR1, SR2, …, SR M-1 , SR M are row selection circuits of the 1st, 2nd, 3rd, …, M-1st and Mth rows, respectively. N-1 INT1, INT2, …, INT NThe first, second, third, …, N-1, N columns of integrator circuits, ADC is an analog-to-digital converter, namely A / D converter, or simply ADC, usually refers to an electronic element that converts analog signals into digital signals.

[0029] In addition, the detector can also include power supply circuit, processor peripheral circuit, transmission circuit, etc. In some embodiments of the application, by adding additional interference detection circuit, such as electromagnetic field detection circuit, which is equivalent to adding a sensor for external interference detection, the interference detection circuit can include interference detection sensor, filter circuit, analog-to-digital converter, etc. The interference detection sensor can be a voltage sensor for detecting power fluctuations, a current sensor, or an electromagnetic field sensor for detecting spatial interference. Through the interference detection circuit, the external interference signal and its strength are detected, which prepares for subsequent interference subtraction.

[0030] On the other hand, the application also provides a method for improving the image anti-interference performance of the above-mentioned detector, specifically as Figure 2 shown.

[0031] S1: In the normal acquisition mode of the detector, the readout circuit reads the signal response data S of the pixel array row by row; at the same time, S2: The interference detection circuit detects and outputs the interference intensity data R; S3: Calculate the effective signal response data V, the calculation formula is as follows: V=S-(R·K),(1) K=S C / R C , (2) Where K is the interference response coefficient, S C is the detector response data due to interference, R C is the corrected interference intensity data detected by the interference detection circuit; in the normal acquisition mode, the user controls whether the detector is in the X-ray illumination environment and when to start image acquisition according to needs.

[0032] In the above scheme, for the same row of pixels, the readout circuit reads the signal response data S synchronously with the interference detection circuit detecting the interference strength data R, that is, S1 and S2 are performed synchronously, the start time and the collection frequency of the interference detection circuit and the row readout circuit of the detector are completely consistent, and the row interference strength data output by the interference detection circuit in the single-row collection process corresponds to the N-column response data read by the detector in this row. Alternatively, in some embodiments, the synchronization of the detector and the interference detection circuit is achieved by the following method: the X-ray detector directly outputs a row collection pulse, and the row collection pulse is used as the data collection control signal of the interference detection circuit. In this way, when the detector readout circuit starts row collection, a row collection pulse is automatically sent to the interference detection circuit, and the interference detection circuit starts collecting interference signals as a trigger signal. In this way, the interference detection circuit collecting interference signals and the row collection circuit collecting each row of pixel data can always be synchronized, that is, the row collection circuit of the detector starts collecting pixel data in a row at the same time as the interference detection circuit starts collecting interference signals. In this way, the corresponding external interference data during the collection of the pixel data in the row by the detector can be obtained, thereby facilitating subsequent interference subtraction to correct the row of pixels. Since the interference detection circuit and the row collection circuit are always synchronized, each row of pixels can be accurately corrected.

[0033] In the above scheme, when calculating the effective signal response data V, the interference response coefficient K is needed. This interference response coefficient should be obtained in advance through an interference correction mode before the user normally collects, and then stored in the detector. Then, when the user normally uses the detector to collect images, the interference response coefficient K corrected in advance is directly used. Alternatively, according to different correction ideas, the method for obtaining the interference response coefficient K is different, and the interference correction mode is also different.

[0034] Alternatively, in some embodiments, the X-ray detector is adjusted to a first interference correction mode, and the interference response coefficient K of the detector is obtained in the first interference correction mode. In the first interference correction mode, no X-ray is irradiated, that is, the X-ray of the detector is not turned on, but external interference is provided to the detector, including at least one of electrostatic discharge, power supply fluctuation, power supply surge, power frequency magnetic field interference, radio frequency conduction, and radiation interference. The external interference can be one or a plurality of superimposed together, or a plurality of the same type of interference superimposed together. If the interference is a plurality of interference or a plurality of interference, the above interference detection circuit is also designed to be multi-channel to detect different channels or different types of interference. In the first interference correction mode, no X-ray is provided and only external interference is provided, and the detector reads the pixel data in the absence of X-ray irradiation, that is, the response data S caused by the interference on the detector C, the response data of the detector under the interference and the interference intensity data R C , the response data of the detector under the interference and the interference intensity data R C平均 , the response data of the detector under the interference and the interference intensity data R C , the response data of the detector under the interference and the interference intensity data R C平均 , the response data of the detector under the interference and the interference intensity data R C1 , the response data of the detector under the interference and the interference intensity data R C1 , the response data of the detector under the interference and the interference intensity data R n , the response data of the detector under the interference and the interference intensity data R n , the response data of the detector under the interference and the interference intensity data R n , the response data of the detector under the interference and the interference intensity data R , the response data of the detector under the interference and the interference intensity data R , the response data of the detector under the interference and the interference intensity data R n , the response data of the detector under the interference and the interference intensity data R n , the response data of the detector under the interference and the interference intensity data R

[0035] , the response data of the detector under the interference and the interference intensity data R

[0036] Specifically, according to different actual needs and image requirements, the calculation of the interference response coefficient K can adopt the whole calculation or the row-by-row calculation.

[0037] Optionally, in some embodiments, the interference response coefficient K is obtained by adopting the whole calculation, at this time, the acquisition method of the interference response coefficient K is as shown in Figure 3 , which comprises: S01: providing an interference to the detector, the interference including at least one of electrostatic discharge, power supply fluctuation, power supply surge, power frequency magnetic field interference, radio frequency conduction, and radiation interference; S02: reading out, by the readout circuit, a response data matrix {C （m）(n)} of all pixels of the pixel array as S C ; while the readout circuit reads out the response data of a certain row of the pixel array, the interference detection circuit detects row interference intensity data corresponding to the row, and iterates through all rows to obtain a matrix {C (m)} of size M*1 as R C , where 1≤m≤M and 1≤n≤N, and M and N are respectively the number of rows and the number of columns of the pixel array of the detector; S03: calculating K=S C / R C .

[0038] In some other embodiments, the interference response coefficient K can also be obtained by row-by-row calculation, and the method for obtaining the interference response coefficient K is shown in Figure 4 , and includes the following steps: S001: providing an interference to the detector, the interference including at least one of electrostatic discharge, power supply fluctuation, power supply surge, power frequency magnetic field interference, radio frequency conduction, and radiation interference; S002: reading out, by the readout circuit, response data of the mth row of pixels of the pixel array to obtain a matrix {C m(n)} as the response data S Cm of the mth row; meanwhile, the interference detection circuit detects row interference intensity data R Cm corresponding to the mth row, where 1≤m≤M and 1≤n≤N, and M and N are respectively the number of rows and the number of columns of the pixel array of the detector; S003: calculating the interference response coefficient K m of the mth row by K Cm =S Cm / R m . S004: iterating through all rows of the pixel array of the detector to obtain a matrix {K （m）(n)} of interference response coefficients corresponding to all pixels as the interference response coefficient K.

[0039] For example, for a 1024 row*1280 column pixel array, the 1280 column interference response data matrix {C 1(n)} corresponding to the first row of pixels and the first row interference intensity R C1 are divided by each other to obtain the 1280 column interference response coefficient matrix {K 1(n)} corresponding to the first row of pixels, and the same method is used to expand row by row to obtain the interference response coefficient matrix {K （m）(n)}, that is, the interference response coefficient K.

[0040] The interference response coefficient K can also be obtained in other ways. Optionally, in some embodiments, the interference response coefficient K is obtained in a second interference correction mode by adjusting the X-ray detector to the second interference correction mode. At this time, the method for obtaining the interference response coefficient K is as shown in Figure 5 , which includes: S0001: providing interference to the detector, the interference including at least one of electrostatic discharge, power supply fluctuation, power supply surge, power frequency magnetic field interference, radio frequency conduction, and radiation interference; S0002: turn on the X-ray, and the detector obtains a gray value image P1 of the correction sample in the interference environment; in the process of obtaining the gray value image P1 of the correction sample in the interference environment, the detector readout circuit reads the response data of a certain row of pixel arrays, and the interference detection circuit detects the row interference intensity data corresponding to the row at the same time, and all rows are traversed to obtain a matrix {C (m)} as R C , where 1≤m≤M and 1≤n≤N, M and N are the number of rows and columns of the detector pixel array, respectively; S0003: obtaining a bias dark field gray value image P2 of the detector in a non-interference environment; S0004: subtracting P2 from P1 to obtain an interference response image P3, and each pixel value of the interference response image P3 is the interference response data S C , wherein the gray value image P1 and the gray value image P2 are obtained based on the same detector and / or detector parameters; S0005: obtaining K=S C / R C to calculate K.

[0041] Compared with the first correction mode, the interference response data matrix obtained by subtracting the bias dark field gray value image in the second correction mode is more accurate. Optionally, in some embodiments, the bias dark field gray value image in the non-interference environment is generated at the time of factory shipment and stored in the X-ray detector. The detector directly subtracts to optimize the user experience during the acquisition process, and can also be generated by the user to ensure real-time performance; in order to improve the accuracy, the above-mentioned bias dark field gray value image can also be obtained by averaging multiple bias dark field gray value images.

[0042] After the interference response coefficient K is determined by the above scheme, the image acquisition and correction can be performed through the normal acquisition mode. The determination of the interference response coefficient K can be that, before the detector is shipped, the detector is corrected and calibrated for various different types of interference, and the influence of the interference on the image, that is, the interference response coefficient K, is found. Alternatively, after the user buys the detector, the corresponding correction and calibration can be performed according to the actual use environment, so that the detector is more suitable for the actual use scene of the customer, and the image performance is more reliable and real.

[0043] Alternatively, according to specific actual application requirements and image requirements, the interference correction can also be corrected in whole or row by row during normal acquisition. Specifically, in some embodiments of the present application, the method adopts whole correction, that is, although the detector row acquisition and the interference detection circuit are synchronized, no deduction calculation is performed in this process, and after the detector acquires a frame of image, the interference detection circuit also synchronously acquires the interference intensity data corresponding to all rows, and then the deduction calculation is performed based on the whole frame of image and the interference intensity data of all rows to obtain the effective signal response data V. At this time, the above scheme can be specifically refined as follows, specifically as shown in Figure 6 .

[0044] S10: In the normal acquisition mode of the detector, the detector is in the external interference and X-ray illumination environment, and the detector simultaneously responds to the external interference and the X-ray illumination environment. In the image acquisition process, the readout circuit reads the signal response data of all pixels of the pixel array row by row to obtain a frame of signal response data matrix matrix {S （m）(n)} corresponding to M rows and N columns of pixels one by one, as the signal response data S; S20: While the readout circuit reads the signal response data of a row of pixel array, the interference detection circuit detects the row interference intensity data corresponding to the row, and traverses all rows to obtain a matrix {R (m)} of size M*1, as the interference intensity data R, where 1≤m≤M, 1≤n≤N, and M and N are the number of rows and columns of the pixel array of the detector, respectively.

[0045] Then, the above S3 step is executed, and the signal response data S and the interference intensity data R obtained by the steps S10 and S20 are used to calculate the effective signal response data V, that is, the corrected image data. For example, the interference response coefficient matrix {K 1(n)} of the N columns of pixels corresponding to the first row is multiplied by the first row interference intensity R (1) to obtain the interference response data matrix {S R1(n)} of the N columns of pixels corresponding to the first row. The same method is used to expand row by row to obtain the interference response data matrix {S R（m）(n)} corresponding to all pixels. The signal response data matrix matrix {S （m）(n)Subtracting the interference response data matrix {S R（m）(n)} corresponding to all pixels, that is, the effective signal response data matrix of the image, that is, the effective signal response data V.

[0046] The overall correction method is to synchronize the line acquisition and the interference signal acquisition, store the pixel data acquisition and the interference signal intensity data acquisition of all lines after each completion, and then perform overall correction based on the overall image and the interference data corresponding to each line of the image, and output the corrected effective image. Such a method sequentially acquires pixel data of each line by the row readout circuit without waiting, and the image readout speed is not affected.

[0047] Alternatively, in some other embodiments of the present application, row-by-row correction can also be used, that is, the detector line acquisition and the interference detection circuit are synchronized, and the subtraction calculation is performed simultaneously during the line acquisition, that is, the detector acquires the image of one line of pixels, and the interference detection circuit also synchronously acquires the interference intensity data corresponding to the line, and then the effective signal response data of the line is calculated by using the above formula for calculating the effective signal response data, and the detector directly outputs the corrected data of the line. Repeat this until all lines of data are acquired and corrected, and the effective signal response data V of the entire image is obtained. At this time, the above method is as shown in Figure 7 , and specifically includes: S100: In the normal acquisition mode of the detector, the readout circuit reads the signal response data of the mth line of pixels to obtain the matrix {S m（n）} as the signal response data S m of the mth line; at the same time, S200: The interference detection circuit detects the row interference intensity data R m corresponding to the mth line, where 1≤m≤M and 1≤n≤N, M and N are the number of rows and columns of the pixel array of the detector, respectively; S300: The effective signal response data V m of the mth line is calculated by the formula V m = S m - (R m ·K); S400: Traverse all lines of the pixel array of the detector to obtain the effective signal response data matrix {V （m）(n)} corresponding to all pixels as the effective signal response data V.

[0048] Taking a pixel matrix of 1024 rows * 1280 columns flat panel detector as an example, the time when the interference detection circuit starts to collect the interference intensity each time is consistent with the time when the flat panel detector starts to collect the data of each row of pixels, that is, the flat panel detector starts to collect a row of pixels, and the interference detection circuit synchronously collects the interference intensity once, and the frequency of the two is consistent and is 100 kHz.

[0049] (1) Before the user normally collects, the flat panel detector enters the interference correction mode, and in this mode, the flat panel detector is kept in the X-ray-free scene, and then the flat panel detector performs row-by-row reading to obtain a frame of interference response data matrix {C （m）(n)} corresponding to 1024 rows * 1280 columns of pixels, and the interference detection circuit correspondingly outputs a row interference intensity data matrix {R (m)} of 1024 * 1, wherein 1≤m≤1024, 1≤n≤1280; (2) The 1280-column interference response data matrix {C 1(n)} corresponding to the first row of pixels is divided by the first row interference intensity R C1 to obtain the interference response coefficient matrix {K 1(n)} of the 1280 columns of pixels corresponding to the first row, and the interference response coefficient matrix {K （m）(n)} corresponding to all pixels can be obtained by using the same method to expand row by row. (3) The flat panel detector enters the normal collection mode, and in this mode, the flat panel detector is in the external interference and X-ray illumination environment, and the flat panel detector simultaneously responds to the external interference and X-ray illumination environment, and in the image collection process, the flat panel detector performs row-by-row reading to obtain a frame of signal response data matrix {S （m）(n)} corresponding to 1024 rows * 1280 columns of pixels, and the interference detection circuit correspondingly outputs a row interference intensity data matrix {R (m)} of 1024 * 1, wherein 1≤m≤1024, 1≤n≤1280; (4) The 1280-column interference response coefficient matrix {K 1(n)} corresponding to the first row of pixels is multiplied by the first row interference intensity R （1） to obtain the interference response data matrix {S R1(n)} of the 1280 columns of pixels corresponding to the first row, and the interference response data matrix {S R（m）(n)} corresponding to all pixels can be obtained by using the same method to expand row by row. (5) The signal response data matrix {S （m）(n)} is directly subtracted from the interference response data matrix {S R1(n)} to obtain the effective signal response matrix after the interference contribution is deducted, that is, the gray value image data after the interference contribution is deducted.

[0050] The row-by-row correction mode is to directly utilize the interference intensity data of the external interference detected by the interference detection circuit during the reading of the pixel data of the row to perform synchronous correction calculation during the row acquisition, so that each row output by the detector is directly the corrected effective image, and after all the pixels of all the rows are acquired, a frame of effective image without interference horizontal stripe is directly output. Such method completes the interference correction during the row reading, and the row data output is directly the corrected effective data, so that the storage of the row acquisition data and the interference data is omitted, the overall calculation time is optimized, and the detector directly outputs the corrected effective image.

[0051] The present application takes the external interference as the signal input of the X-ray detector, adds an interference correction mode in the application of the X-ray detector, and does not input the effective signal in the mode, so that the image output of the X-ray detector only contains the response to the external interference signal. Meanwhile, an interference detection circuit is added in the X-ray detector, and the interference response coefficient of the X-ray detector to the external interference intensity is obtained by simultaneously collecting the same external interference signal by the X-ray detector and the interference detection circuit. In the normal acquisition mode, the interference detection circuit and the X-ray detector are also simultaneously collected, so that the image output of the X-ray detector corresponds to the sum of the effective signal input by the user and the response of the external interference signal. The interference response coefficient obtained in the interference correction mode and the interference intensity of the interference detection circuit in the normal acquisition mode can restore the contribution of the external interference signal part in the image output of the X-ray detector in the normal acquisition mode. After the contribution is deducted, the X-ray detector image corresponding to the effective signal input by the user is obtained. In addition, the present application uses the interference response coefficient to quantify the response of the unit intensity interference on the detector image. According to the interference response coefficient, the contribution of the detector image response data under any intensity interference can be obtained. Therefore, the anti-interference method of the present application is suitable for various intensity interferences, and is also suitable for any frequency interference. As long as the interference and the interference intensity can be detected by the interference detection circuit, the contribution value of the interference to the image can be obtained. Therefore, the present application is suitable for any frequency and any intensity interference, has strong applicability, and the applicability and reliability of the detector using the method of the present application are also higher, and has a milestone significance in the field of X-ray detector image improvement.

[0052] Finally, it should be pointed out that: the above embodiments are only used to illustrate the technical solutions of the present application, but not to limit them. Although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that they can modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacement to some technical features, and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A method for improving the anti-interference performance of an image, characterized in that: include In the normal acquisition mode of the detector, the readout circuit reads the signal response data S of the pixel array row by row; at the same time, The interference detection circuit detects and outputs interference intensity data R; Calculate the effective signal response data V, the calculation formula is as follows: V=S-(R·K), K=S C / R C , Among them, K is the interference response coefficient, S C is the detector response data caused by interference, R C Corrected interference intensity data detected by the interference detection circuit; For the same row of pixels, the signal response data S read by the readout circuit is synchronized with the interference intensity data R detected by the interference detection circuit.

2. The method according to claim 1, characterized in that The method adopts an overall correction, specifically including: The readout circuit reads the signal response data of all pixels in the pixel array row by row to obtain the matrix {S （m）(n) }, as signal response data S; While the readout circuit reads the signal response data of a row of pixel arrays, the interference detection circuit detects the row interference intensity data corresponding to the row, traverses all rows, and obtains the M*1 size matrix {R (m) }, as the interference intensity data R, where 1≤m≤M, 1≤n≤N, M and N are the number of rows and columns of the detector pixel array, respectively.

3. The method according to claim 1, characterized in that The method adopts row-by-row correction, specifically comprising: In the normal acquisition mode of the detector, the readout circuit reads the signal response data of the pixels in the mth row and obtains the matrix {S m（n） }, as the signal response data S of the mth row m At the same time, the interference detection circuit detects the row interference intensity data R corresponding to the mth row m , where 1≤m≤M, 1≤n≤N, M and N are the number of rows and columns of the detector pixel array respectively; By formula V m =S m -(R m K) Calculate the effective signal response data V of the mth row m ; Traverse all rows of the detector pixel array to obtain the effective signal response data matrix {V （m）(n) }, as a valid signal response data V.

4. The method according to claim 1, wherein The interference response coefficient K is obtained in a first interference correction mode, where there is no X-ray irradiation. The method for obtaining the interference response coefficient K includes: Providing interference to the detector, wherein the interference includes at least one of electrostatic discharge, power fluctuation, power surge, power frequency magnetic field interference, radio frequency conduction, and radiation interference; The readout circuit reads the response data matrix of all pixels in the pixel array row by row {C （m）(n) }, as S C ; While the readout circuit reads the response data of a row of pixel arrays, the interference detection circuit detects the row interference intensity data corresponding to the row, traverses all rows, and obtains the matrix {C (m) }, as R C , where 1≤m≤M, 1≤n≤N, M and N are the number of rows and columns of the detector pixel array respectively; By K=S C / R C Calculate K.

5. The method according to claim 1, wherein The interference response coefficient K is obtained in a first interference correction mode, where there is no X-ray irradiation. The method for obtaining the interference response coefficient K includes: Providing interference to the detector, wherein the interference includes at least one of electrostatic discharge, power fluctuation, power surge, power frequency magnetic field interference, radio frequency conduction, and radiation interference; The readout circuit reads the response data of the pixel in the mth row of the pixel array and obtains the matrix {C m(n) }, as the response data S of the mth row Cm ;at the same time, The interference detection circuit detects the row interference intensity data R corresponding to the mth row Cm , where 1≤m≤M, 1≤n≤N, M and N are the number of rows and columns of the detector pixel array respectively; By K m =S Cm / R Cm Calculate the interference response coefficient K of the mth row m ; Traverse all rows of the detector pixel array and obtain the interference response coefficient matrix {K （m）(n) }, as the interference response coefficient K.

6. The method according to claim 1, characterized in that The interference response coefficient K is obtained in the second interference correction mode. The method for obtaining the interference response coefficient K includes: Providing interference to the detector, wherein the interference includes at least one of electrostatic discharge, power fluctuation, power surge, power frequency magnetic field interference, radio frequency conduction, and radiation interference; Turn on the X-ray, the detector obtains the gray value image P1 of the calibration sample in an interference environment; When the detector obtains the grayscale value image P1 of the calibration sample in the interference environment, the detector readout circuit reads the response data of a row of pixel arrays while the interference detection circuit detects the row interference intensity data corresponding to the row. By traversing all rows, a matrix {C (m) }, as R C , where 1≤m≤M, 1≤n≤N, M and N are the number of rows and columns of the detector pixel array respectively; Obtain the biased dark field grayscale value image P2 of the detector in an interference-free environment; Subtract P2 from P1 to get the interference response image P3. The pixel values ​​of the interference response image P3 are the interference response data S of the detector. C , wherein the gray value image P1 and the gray value image P2 are obtained based on the same detector and / or detector parameters; By K=S C / R C Calculate K.

7. The method according to claim 6, characterized in that The biased dark field grayscale value image in the non-interference environment is generated and stored in the X-ray detector at the factory.

8. The method according to claim 1, characterized in that For the same row of pixels, the readout circuit reads the signal response data S and the interference detection circuit detects the interference intensity data R synchronously, including: when the readout circuit starts row acquisition, it outputs a row acquisition pulse, and the row acquisition pulse serves as a data acquisition control signal for the interference detection circuit.

9. A detector capable of improving image anti-interference performance, used to implement the method according to any one of claims 1 to 8, characterized in that: The detector includes an M×N pixel array, a readout circuit, a processor and an interference detection circuit. The readout circuit is electrically connected to the processor and is used to transmit the read data of the pixel array to the processor. The interference detection circuit is electrically connected to the processor and is used to transmit the detected interference data to the processor. The processor is used to calculate the effective signal response data V.

10. The detector according to claim 9, characterized in that The detector further includes a storage module, which stores a biased dark field grayscale value image of the detector in a non-interference environment.

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