Method of X-ray fluorescence spectrum background rejection

Abstract

The invention discloses a method of X-ray fluorescence spectrum background rejection. Iterative wavelet transform is used to analyze the X-ray fluorescence spectrum, which overcomes the defect that spectrum distortion is easily caused when traditional wavelet transform is used to reject the spectrum background. When the characteristic peak and the frequency band of the background coincide, the method provided by the invention can still effectively extract the pure characteristic peak. The concept of wavelet approximation energy is presented in the invention and is used to evaluate the distribution situation of the background energy at a low frequency band. Compared with wavelet energy, the wavelet approximation energy can be used for more directly and accurately evaluating the spectrum background at a low frequency band. According to the method, wavelet entropy is used to select an optimal wavelet basis; after dilation and translation, the optimal wavelet basis can better match the whole or partial spectrum, and the spectrum sparsity after wavelet transform can be increased, and the operational efficiency is improved.

Description

technical field [0001] The invention relates to an X-ray fluorescence spectrum background subtraction method, which belongs to the field of spectrum processing. Background technique [0002] Since the energy dispersive X-ray fluorescence (EDXRF) spectrometer entered the analytical instrument industry in the early 1970s, it has been used in iron and steel metallurgy, petrochemical, geological and mineral resources due to its advantages of fast analysis speed, high accuracy, and no pollution to samples. , cultural relic identification, biomedicine and many other fields have been widely used. In particular, the implementation of the EU RoHS directive has made it more widely used. [0003] Energy dispersive X-ray fluorescence spectroscopy uses an excitation source to generate X-rays, irradiates the sample, and excites the characteristic X-rays of the elements contained in the sample. The detector receives the characteristic X-rays and converts them into electrical signals, whic...

AI Technical Summary

Problems solved by technology

[0011] Aiming at the problems that it is difficult to select the optimal wavelet function and wavelet approximation to fit the background when wavelet transform is used for spectral background subtraction, the present invention proposes a method for iteratively performing wavelet transform to subtract X-ray fluorescence spectral background , use wavelet entropy to select the optimal wavelet function, and use wavelet energy as a judgment standard to stop iterations in a timely manner and reduce unnecessary calculations

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