Coincidence technique-based x-ray detection device and composition analysis method

A coincidence technique-based X-ray detection device, comprising:

• a sample holding device, which is used for holding a sample to be detected;
• an excitation unit, which is arranged above the sample holding device, and is configured to output X-rays with a continuously adjustable energy that interact with the sample to be detected, so as to excite the sample and generate secondary X-rays;
• detectors, which are configured to detect signals of the secondary X-rays, the detectors comprise two SiC semiconductor detectors and two SiPIN semiconductor detectors, and the detectors are spaced apart and are arranged circumferentially around the sample holding device;
• a signal processing unit, which is configured to perform an amplification, an analog-to-digital conversion, and a classification on the detected signals to obtain energy information;
• a data processing device, which is connected to the signal processing unit, and is configured to perform an analysis and a calculation according to the energy information, and determine an element type and a content in the sample to be tested, the data processing device comprises a processor and a memory, and the processor is configured to execute following program modules stored in the memory:
• a storage module, which is configured to store known elements and X-ray energy information of the known elements;
• a baseline recovery module, which is configured to perform a baseline recovery according to an average value and a median value of energies in the energy information to obtain true amplitude energy information so as to eliminate a baseline drift;
• a calibration curve construction module, which is configured to construct a calibration curve according to peak positions and peak energies of known standard samples;
• an extraction module, which is configured to extract peak positions and peak energies in the true amplitude energy information, wherein a threshold is set in the extraction module, and energies in the true amplitude energy information that reach or exceed the threshold are considered to be peaks;
• an effective energy information determination module, which is configured to extract time information of the detectors, and take a time point when a first energy in the true amplitude energy information reaches or exceeds the threshold as an initial time, select a time window, and the true amplitude energy information within the time window is considered to be effective energy information;
• and
• a peak comparison module, which is configured to compare the effective energy information with the X-ray energy information of the known elements in the calibration curve to determine the element type and the content in the sample.