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CN-121971115-A - Calibration method based on flying focus x-ray imaging system

CN121971115ACN 121971115 ACN121971115 ACN 121971115ACN-121971115-A

Abstract

The invention discloses a calibration method based on an X-ray imaging system with a flying focus, which belongs to the technical field of X-ray scanning and comprises the following steps of S1, building a calibration environment, S2, scanning the focus, controlling electronic deflection by a deflection system to enable the focus to move point by point in a focus plane, S3, collecting data, collecting signals generated after X-rays pass through a hole slot by a detector, S4, searching an effective focus, automatically searching the focus aligned with the hole slot by an algorithm, S5, updating data, and refreshing a system configuration table and current parameters. According to the calibration method based on the flying focus X-ray imaging system, the calibration work of the flying focus imaging system is realized through a simple process and a medium-grade process, the independent calibration scheme of a subsystem depending on a precision grade process and a complex subsystem is replaced, the usability of a product is improved, and the production, processing and maintenance costs are reduced.

Inventors

  • DING XIANLI
  • Shi Xingyin

Assignees

  • 北京方隅探维科技有限公司

Dates

Publication Date
20260505
Application Date
20260316

Claims (9)

  1. 1. A calibration method based on an X-ray imaging system with an aerial focus is characterized by comprising the following steps: S1, setting up a calibration environment, wherein portable equipment can be placed on a platform, a scatterer is placed right in front of the equipment, the power supply is turned on, and the equipment enters a calibration interface from a software UI interaction system; S2, after a focus scanning and calibration process is started, the deflection system automatically controls electronic deflection to enable the focus to move point by point in a focal plane, and then two-dimensional scanning is performed from point to line and from line to surface; s3, data acquisition, wherein during focus scanning, the detector synchronously acquires signals scattered back from a scatterer; S4, searching an effective focus, namely searching for the focus which can be aligned with the hole slot, wherein when the focus moves to the position aligned with the hole slot, the passing radiation dose reaches the local maximum, and when the radiation dose deviates from the aligned position, the dose is reduced, and the algorithm automatically searches for the effective focus according to the characteristic; S5, updating data, storing deflection parameters and signal strength corresponding to the searched focus into a system configuration table, and refreshing current system parameters.
  2. 2. The method of calibrating an x-ray imaging system based on an aerial focus as set forth in claim 1, wherein the calibration mode is converted by converting the independent calibration of each subsystem into a one-time integrated calibration, and converting the deviation of the geometric position into the intensity of the signal detected by the detector.
  3. 3. The method for calibrating an x-ray imaging system based on a flying focus according to claim 2, wherein the deviation of the geometric position is converted into a method for detecting the intensity of the signal, specifically, when the focus is aligned with the corresponding hole slot, the radiation is led out of the hole slot to have a large dose, the dose is reduced when the focus is deviated from the alignment, the dose scattered back through the scatterer is in a linear relationship with the dose passing through the hole slot, and therefore, the intensity of the scattered signal acquired by the detector is related to the magnitude of the deviation of the geometric position.
  4. 4. A calibration method based on an X-ray imaging system with an on-the-fly focus as set forth in claim 3, wherein the deflection system controls the focus movement mode, specifically, the deflection system can control electrons to deflect along the up-down dimension and the left-right dimension, and control the position of the electrons bombarding the target material to move according to a preset step length from point to line and then from line to plane, so as to form two-dimensional scanning.
  5. 5. The method of calibrating an x-ray imaging system based on an aerial focus of claim 4, wherein the detector synchronously collects signals as the focus moves point by point, and the collected signal values are arranged in a two-dimensional image according to the corresponding focus positions.
  6. 6. A method of calibrating an x-ray imaging system based on an aerial focus as defined in claim 5 wherein the active focus search searches for all focus points aligned with the aperture slot.
  7. 7. A method of calibrating an x-ray imaging system based on an aerial focus as defined in claim 6 wherein the active focus routine searching step deflects the focus in small steps throughout the world and positions all of the focus in one global scan.
  8. 8. The method for calibrating an x-ray imaging system based on an aerial focus of claim 7, wherein the effective focus fast searching step: coarse positioning, namely performing global searching by using a large step length, and coarsely positioning a focus; Fine positioning, namely searching near each rough positioning focus by a smaller step length, and fine positioning the focus position.
  9. 9. The method of calibrating an x-ray imaging system based on an feints of claim 8, wherein the local maxima search algorithm, when the focus moves to a position aligned with a slot, the detector signal is strongest in a small nearby area, but not globally strongest, so that the local maxima search algorithm is used to search for all extremal points on the two-dimensional map, specifically comprising: The convolution peak searching method comprises taking a proper Gaussian convolution template, removing noise smoothly by convolution, and searching the peak position by gradient method, wherein the gradient characteristics of the peak before and after the peak are changed from more than zero to less than zero, and the trough is just opposite, or The binary connected region method is to use a local self-adaptive Sauvola algorithm to binarize the image, use a morphological corrosion algorithm to remove small noise points, then use a connected region algorithm to search each connected region, and finally calculate the central position of the connected region.

Description

Calibration method based on flying focus x-ray imaging system Technical Field The invention relates to the technical field of x-ray scanning, in particular to a calibration method based on an x-ray imaging system with a flying focus. Background The X-ray flying spot scanning imaging system consists of a flying spot X-ray source subsystem, a static flying spot subsystem, a detector subsystem, a hardware control subsystem, a software subsystem and a data acquisition and processing subsystem, wherein the alignment precision of the X-ray source subsystem and the static flying spot system is required to reach a precision level, and rays can be emitted through the static flying spot system effectively. The existing alignment scheme relies on independent calibration and precision level processes for each relevant link. The electronic deflection system needs to consider temperature difference compensation, edge effect correction and mounting position precision adjustment, the hole slot processing and mounting in the static constraint device need precision, even if the design, processing and mounting of each key system meet the requirements, in the use process, if some external factors are encountered to change the initial state, such as high temperature environment, low temperature environment or affected by vibration, the parameters of the core component or the position of the component are deviated, so that the system cannot work normally, after-sales personnel are required to calibrate each subsystem one by one, and time and labor are wasted. Therefore, there is a need for a calibration scheme that is simple to operate and does not rely on precision scale processes to solve the problems associated with the prior art schemes. Disclosure of Invention The invention aims to provide a calibration method based on an X-ray imaging system of a flying focus, which realizes the calibration work of the imaging system of the flying focus through a simple process and a medium-grade process, replaces independent calibration schemes depending on a precise grade process and a complex subsystem, improves the usability of products and reduces the production, processing and maintenance costs. To achieve the above object, the present invention provides a calibration method based on an x-ray imaging system with an feints, comprising the steps of: S1, setting up a calibration environment, wherein portable equipment can be placed on a platform, a scatterer is placed right in front of the equipment, the power supply is turned on, and the equipment enters a calibration interface from a software UI interaction system; S2, after a focus scanning and calibration process is started, the deflection system automatically controls electronic deflection to enable the focus to move point by point in a focal plane, and then two-dimensional scanning is performed from point to line and from line to surface; s3, data acquisition, wherein during focus scanning, the detector synchronously acquires signals scattered back from a scatterer; S4, searching an effective focus, namely searching for the focus which can be aligned with the hole slot, wherein when the focus moves to the position aligned with the hole slot, the passing radiation dose reaches the local maximum, and when the radiation dose deviates from the aligned position, the dose is reduced, and the algorithm automatically searches for the effective focus according to the characteristic; S5, updating data, storing deflection parameters and signal strength corresponding to the searched focus into a system configuration table, and refreshing current system parameters. Preferably, the conversion of the calibration mode is to convert the independent calibration of each subsystem into one-time comprehensive calibration and convert the deviation of the geometric position into the strength of the signal detected by the detector. Preferably, the geometric position deviation is converted into the detection signal intensity, specifically, when the focus is aligned with the corresponding hole slot, the radiation is large in dosage which is led out through the hole slot, the dosage which is reduced when the focus is deviated from the alignment, and the dosage which is scattered back through the scatterer is in a linear relation with the dosage which is led through the hole slot, so that the intensity of the scattered signal collected by the detector is related to the geometric position deviation. Preferably, the deflection system controls the focus to move, and the deflection system can control the electrons to deflect along the up-down and left-right dimensions, and control the position of the electrons bombarding the target material to move according to a preset step length, and the two-dimensional scanning is formed from point to line and then from line to surface. Preferably, in the signal acquisition mode, along with the point-by-point movement of the focus, the detector synchronously acquires signals