Method for reducing stray light of atomic absorption spectrum instrument using visible cut-off type optical filter and light path system thereof

Abstract

The invention discloses a method for reducing the stray light for an atomic absorption spectrometer by using a visible cut-off filter. When the wavelength set by the spectrometer is within 190 to 400 nm of ultraviolet band, a light path is cut-in by the cut-off filter for reducing the stray light; and when the wavelength set by the spectrometer is within 400 to 900 nm of visible range, a light path is cut-out by the cut-off filter. The invention can basically eliminate the stray light of the measured element, the wavelength of which is in the ultraviolet band, only by adding one filter, thereby the light precision, the linear range and the background correction capability of the atomic absorption spectrometer are greatly enhanced; and the background correction capability of the spectrometer can be improved to more than100 times (1Abs) and to more than 80 times (2Abs) when the technology is applied to the high performance self-absorption background correction of the atomic absorption spectrometer.

Description

technical field [0001] The invention belongs to the field of spectral analysis instruments, and in particular relates to a method for reducing stray light of the atomic absorption spectrometer by using a visible cut-off filter in the atomic absorption spectrometer. The invention also relates to an optical system using the method. technical background [0002] Since the 1950s, the Australian physicist Walsh first proposed the application of atomic absorption spectroscopy to chemical analysis, and it has become one of the most important tools for element quantitative analysis and is widely used in various analysis fields. The size of stray light is an important index of spectroscopic instrument performance. When the atomic absorption spectrometer needs to achieve good optical accuracy, wide linear range, and high background correction ability, the influence of stray light is particularly important. [0003] Stray light refers to the light separated from the monochromator tha...

AI Technical Summary

Problems solved by technology

Due to the influence of stray light, the self-absorption background absorption ability of traditional atomic absorption spectrometers only provides the background correction ability when the absorbance is 1Abs (the national standard requires not less than 30 times), and the background correction ability when the absorbance is above 1.5Abs is usually less than 30 times

[0007] At home and abroad, there is no method of using visible cut-off filters in atomic absorption spectrometers to reduce the stray light of atomic absorption spectrometers and spectroscopic instruments using this method

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