Method for eliminating base line interference in Raman spectrum by utilizing fluorescent bleaching effect

Abstract

The invention discloses a method for eliminating base line interference in a Raman spectrum by utilizing fluorescent bleaching effect, and relates to a method for eliminating base line interference in the Raman spectrum. According to the method, by measuring a spectral signal S of a sample, the difference delta S and the average value delta S' of a series spectral signal can be calculated, denoising processing is carried out on the average value delta S', and the average value delta S' of the difference after denoising is taken as the metric Fs of florescence contained by the sample spectrum signal; the metric Fs of florescence is gradually abated from the sample spectrum signal, so that whether abatement reaches the requirements can be judged, and if so, the base line interference in the Raman spectrum is eliminated, and a pure Raman spectrum signal is obtained. According to the method, the authenticity and the reasonability of data processing can be ensured, the adopted equipment is simple and low in manufacture cost, and the method is simple and easy to popularize.

Description

technical field [0001] The invention relates to a method for eliminating baseline interference in Raman spectrum, in particular to a method for eliminating baseline interference in Raman spectrum by utilizing the fluorescence fading effect. Background technique [0002] Laser Raman spectroscopy has become an important method for rapid characterization of substances. The Raman spectrum is generated by excitation of a single-wavelength laser, but the fluorescence excited at the same time greatly interferes with the identifiability of the Raman spectrum, which is the most important factor affecting the quality of the Raman signal. In particular, the miniature spectroscopic Raman spectrometer, which has been widely used in recent years, has been widely used in on-site measurement due to its simple structure, portability, and no need for complicated maintenance. However, due to the direct spectroscopic collection of spectra, it is difficult to eliminate through hardware after bei...

AI Technical Summary

Problems solved by technology

The Raman spectrum is generated by excitation of a single-wavelength laser, but the fluorescence excited at the same time greatly interferes with the identifiability of the Raman spectrum, which is the most important factor affecting the quality of the Raman signal

In particular, the miniature spectroscopic Raman spectrometer, which has been widely used in recent years, has been widely used in on-site measurement due to its simple structure, portability, and no need for complicated maintenance. However, due to the direct spectroscopic collection of spectra, it is difficult to eliminate through hardware after being interfered by fluorescence. ; Although the longer excitation wavelength can reduce the probability of fluorescence generation, it is currently constrained by the cost and the performance of components; at the same time, the excitation efficiency of longer wavelength is low, and the possibility of burning the sample is also increased.

[0003] At present, the main method for portable Raman spectrometers to eliminate fluorescence is subtraction through baseline fitting; although it is intuitive to subtract the spectral baseline raised by fluorescence to the original position, this subtraction cannot be mechanistically or substantially It is difficult to guarantee the authenticity and rationality of data processing

Other fluorescence subtractions that conform to the mechanism have put forward requirements for equipment hardware, such as dual-wavelength excitation, using the mobility of Raman light and the relative stability of fluorescence to eliminate fluorescence, but all have the disadvantages of increasing equipment cost and complexity.

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