CN-118986374-B - High-flux X-ray multi-energy spectrum detection system and detection method

CN118986374BCN 118986374 BCN118986374 BCN 118986374BCN-118986374-B

Abstract

The application relates to the technical field of X-ray detection, in particular to a high-flux X-ray multi-energy spectrum detection system and a detection method, wherein the detection method comprises the steps of preparing n filter sheets Z i with different K absorption limits, wherein i is E (1, n), and n is more than or equal to 15; the electric signal S i ,S i ＝∫η×[φ(E)×C i (E)]dE,(E min ,E max is obtained by detecting the collimated incident X-ray after the attenuation of each filter Z i ), the discretization processing is carried out on the electric signal S i , and then the least square solution is solved, so that the incident X-ray energy spectrum is obtained. The application realizes flexible modulation and demodulation of high flux X-ray energy spectrum by the mathematical combination of the filters with different linear attenuation coefficients based on the detection principle of energy integration, and gives consideration to the detection cost and obtains the X-ray energy spectrum with fine resolution.

Inventors

ZHANG QINGLI
Niu guangda
Pang Jincong
LIU YUTING
XU LING
ZHENG ZHIPING
ZHOU YING
TANG JIANG

Assignees

华中科技大学

Dates

Publication Date: 20260512
Application Date: 20240716

Claims (7)

1. The high-flux X-ray multi-energy spectrum detection method is characterized by comprising the following steps of: Preparing n kinds of filter sheets Z i with different K absorption limits, wherein i is E (1, n), and n is more than or equal to 15; The incident X-rays are attenuated by each filter Z i after being collimated; all the attenuated signals are detected to obtain electric signals S i ,S i = [ n ] eta x [ [ (E) X C i (E)]dE,(E min ,E max ), where η is a scaling factor, (E) For the energy spectrum of the incident X-rays, (E min ,E max ) is the energy range of the incident X-rays, Where E is the energy of the incident X-ray, μ i (E) is the attenuation coefficient of filter Z i , and d i is the thickness of filter Z i ; Within (E min ,E max ) energy range, n filter slices divide the energy range into m energy windows W j , j ε (1, m) based on the K absorption limit; The filter Z i is denoted as C ij for C i (E) within each energy window W j , (E) Recorded within each energy window as j Discretizing the electric signal S i to obtain ; Based on Solving least square solution to obtain energy spectrum of incident X-ray 1 、 2 、......、 j 、......、 n 、 m ; Spectral energy spectrum based on incident X-rays 1 、 2 、......、 j 、......、 n 、 m Obtaining an incident X-ray energy spectrum; Wherein the filter Z i is made of a material selected from elements with atomic numbers from 40 to 83, and K absorption limits of n filters Z i are distributed at equal intervals in the energy range (E min ,E max ).
2. The high-throughput X-ray multi-energy spectrum detection method of claim 1, it is characterized in that the method comprises the steps of, n is more than or equal to 30 and less than or equal to 40.
3. The high-throughput X-ray multi-energy spectrum detection method according to claim 1, wherein the elements from 40 to 83 are used for manufacturing the filter Z i in the form of metal simple substance or are used for manufacturing the filter Z i in the form of compound and PVB mixed tablet.
4. A high-throughput X-ray multi-energy spectrum detection method according to claim 3, wherein the compounds are sequentially selected as one of oxides, chlorides or sulphates in terms of stability.
5. A high-throughput X-ray multi-energy spectrum detection method according to claim 3, wherein the mass ratio of compound to PVB is 1:0.45-0.55.
6. The high-throughput X-ray multi-energy spectrum detection method of claim 5, wherein the mass ratio of compound to PVB is 1:0.5.
7. A high-throughput X-ray multi-energy spectrum detection system, comprising: an X-ray emitter for emitting incident X-rays; The collimation mould is arranged behind the X-ray emitter and is used for receiving incident X-rays and collimating the incident X-rays; the filter plate group comprises n filter plates Z i with different K absorption limits, i epsilon (1, n) is more than or equal to 15, and each filter plate Z i is selectively arranged behind the collimating mould and used for attenuating the collimated incident X rays to obtain the emitted X rays; A detector disposed behind the filter Z i for detecting the outgoing X-rays and obtaining an electrical signal S i ; The upper computer is used for receiving the electric signal S i corresponding to each filter Z i and performing inverse solution to obtain an incident X-ray energy spectrum, and specifically comprises the following steps: S i =∫ η×[ (E) X C i (E)]dE,(E min ,E max ), where η is a scaling factor, (E) For the energy spectrum of the incident X-rays, (E min ,E max ) is the energy range of the incident X-rays, Where E is the energy of the incident X-ray, μ i (E) is the attenuation coefficient of filter Z i , and d i is the thickness of filter Z i ; Within (E min ,E max ) energy range, n filter slices divide the energy range into m energy windows W j , j ε (1, m) based on the K absorption limit; The filter Z i is denoted as C ij for C i (E) within each energy window W j , (E) Recorded within each energy window as j Discretizing the electric signal S i to obtain ; Based on Solving least square solution to obtain spectrum of incident X-ray 1 、 2 、......、 j 、......、 n 、 m ; Spectral energy spectrum based on incident X-rays 1 、 2 、......、 j 、......、 n 、 m Obtaining an incident X-ray energy spectrum; Wherein the filter Z i is made of a material selected from elements with atomic numbers from 40 to 83, and K absorption limits of n filters Z i are distributed at equal intervals in the energy range (E min ,E max ).

Description

High-flux X-ray multi-energy spectrum detection system and detection method Technical Field The application relates to the technical field of X-ray detection, in particular to a high-flux X-ray multi-energy spectrum detection system and a detection method. Background In modern medical diagnosis, an X-ray Computed Tomography (CT) technology is widely applied, and a non-contact detection mode is adopted, and based on the absorption characteristics of X-rays on different materials, the structural information and the material composition inside an object are obtained by detecting the attenuation characteristics of the X-rays after passing through the materials. One long-term development in the X-ray field is the transition from single-energy black-and-white images to multi-energy color images, which can effectively distinguish between different densities of matter and extract target object features in combination with subtraction algorithms. Currently, there are two main detection principles in the field of X-ray imaging, one is conventional X-ray imaging based on energy-integrating detectors and one is multi-energy-spectrum X-ray imaging based on photon-counting detectors. The energy integrating detector is a mainstream technology of current products, and the intensity of all photons (flux is about 10 6～109cps/mm2) is obtained in the integrating time (ms-s) of a circuit. The energy integral detector integrally receives X-ray photons with different energies after passing through an object, reflects the average attenuation characteristic of X-rays, cannot distinguish the X-ray photons with different energies, is difficult to distinguish materials with similar density distribution, limits qualitative and quantitative analysis of substances, is easily interfered by radiation hardening and noise, and therefore, the traditional X-ray imaging technology has poor imaging quality, only can draw gray images and cannot obtain multi-energy color images. An experienced physician is required to judge the condition by image contour and gray level. The method of multi-exposure and multi-layer detector side incidence detection of incident X-rays with different energy spectrums is tried to obtain limited energy resolution effect by integral detection, but the pseudo-multi-energy scheme has low energy resolution and low practical application value. The industry would be willing to host photon counting technology to achieve multi-spectral X-ray detection. The photon counting detector has the energy resolving power of single photon of X-ray, can measure photon counting data of a plurality of energy thresholds at the same time, and can obtain multi-energy color images by energy obtaining discrimination photons according to attenuation characteristics (such as low-energy X-ray photons are more sensitive to soft tissues such as lungs and the like, and high-energy photons are more sensitive to hard tissues such as bones and the like). The photon counting detector can obtain energy spectrum data of X-rays, so that attenuation information of substances under a plurality of energy thresholds is provided, a plurality of images can be drawn by utilizing photon counting data of a measured object in a plurality of energy sections, and a fused image with high resolution, high signal to noise ratio and low radiation dose is obtained through an image fusion algorithm. The multi-energy spectrum X-ray imaging technology has the advantages of accurate substance resolution result, high imaging signal-to-noise ratio, strong practicability and low radiation dosage, and has wide application prospect in the field of medical imaging. However, the current photon counting detector has many limitations, namely low counting rate (< 10 8cps/mm2), poor counting stability, limited dead time of the counting rate and the like, which limit the multi-energy X-ray detection effect based on the technology and limit the development speed and application prospect of energy spectrum detection based on the photon counting technology. In the related art, there is a problem that the detection cost and the energy resolution cannot be compatible. Disclosure of Invention In order to achieve the aim of considering the detection cost and resolution in the detection of the X-ray energy spectrum, the application aims to provide a high-flux X-ray multi-energy spectrum detection system and a detection method. In a first aspect, the high-flux X-ray multi-energy spectrum detection method provided by the application adopts the following technical scheme: a high-flux X-ray multi-energy spectrum detection method comprises the following steps: Preparing n kinds of filter sheets Z i with different K absorption limits, wherein i is E (1, n), and n is more than or equal to 15; The incident X-rays are attenuated by each filter Z i after being collimated; The attenuated signals are detected to obtain electric signals S i, Wherein, eta is a proportionality coefficient,For the energy spectrum