Method for calibrating wavelength of ultraviolet spectrograph

Abstract

The invention discloses a method for calibrating wavelength of an ultraviolet spectrograph. The method includes the steps of: (1) starting the ultraviolet spectrograph and a main control computer; (2) starting a standard light source, and preheating for a set time; (3) performing ultraviolet spectral signal acquisition and processing by the main control computer: (3.1) obtaining dark noise of a linear array CCD detector of the ultraviolet spectrograph; (3.2) collecting the ultraviolet spectral signals, and deducting the dark noise obtained in the Step (3.1); (3.3) utilizing a narrow window difference method to perform characteristic spectrum positioning; (3.4) replacing different types of standard light sources; repeating the Step (2) and Steps (3.1) to (3.3) to obtain a peak value position of a characteristic spectrum peak; (3.5) according to the peak value position obtained in the Step (3.4), utilizing a sectional fitting method to perform spectral curve fitting; (3.6) performing reconstruction on the fitted spectral curve; and completing the whole calibration process. The method for calibrating the wavelength of the ultraviolet spectrograph is easy and convenient to operate, has a strong anti-interference capability, and is high in calibration precision.

Description

technical field [0001] The invention relates to a wavelength calibration method for an ultraviolet spectrometer, and belongs to the technical field of wavelength calibration for an ultraviolet spectrometer. Background technique [0002] In the ultraviolet spectrum analyzer using a linear array detector, its spectral wavelength corresponds to the relative position of the linear array detector. Such as figure 1 As shown, the light beam enters the slit from the optical fiber, and the incident light is collimated by the collimator and then reflected into the ultraviolet diffraction grating. The diffraction grating separates the incident light of different wavelengths in space through dispersion and then reflects into the focusing mirror. The wavelength spectrum is reflected to a line detector. The wavelength calibration of the ultraviolet spectrum analyzer is to use the standard light source with recognized characteristic spectral lines to obtain the pixel position of each cha...

AI Technical Summary

Problems solved by technology

[0006] 1. In the prior art, the accuracy of characteristic spectrum peak positioning is easily affected by factors such as stray light, instrument dark noise, random noise, etc., which can easily cause the displacement of several pixels of characteristic spectrum peaks, thereby reducing the positioning accuracy of characteristic spectrum peaks ;

[0007] 2. In the existing technology, the accuracy of spectral line fitting is easily affected by the insufficient number and distribution relationship of the characteristic spectral lines of a single light source, which causes large errors in spectral line fitting, thereby affecting the accuracy of wavelength calibration;

[0008] 3. In the prior art, the effective use of the non-exposed pixels of the line array detector is ignored;

[0009] 4. In the prior art, the calibration device is complex and has high requirements on the external environment, which is not suitable for industrial use

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