单色仪设计与波长精度分析补偿方法研究

Monochromator design and wavelength precision analysis compensation method research

针对紫外-可见光谱定标精度需求,设计了一款波段范围在185~900nm的三光栅单色仪;为提高单色仪的波长扫描精度,降低高精度波长扫描机构在工程上的成本。建立了光栅转角误差对扫描机构波长精度的影响模型,设计了基于高精度编码器的转角误差补偿装置,通过软件不同参数设置和算法设计的补偿算法,实现了波长扫描机构的精度校正;实验结果表明,通过参数算法补偿后,扫描机构的波长准确性精度和波长重复性精度在工作波段范围内有所提高,不同波长下其精度的提高程度不同,其中,波长准确性精度提高比范围为20.8~35.2%,波长重复性精度提高比范围为61.5~95.2%。实验结果验证了误差补偿装置及补偿算法的有效性,提高了波长扫描机构的精度,降低了高精度波长扫描机构在工程应用上的成本。

A three grating monochromator with a wavelength range of 185~900nm was designed to meet the accuracy requirements of UV visible spectrum calibration;To improve the wavelength scanning accuracy of monochromators and reduce the engineering cost of high-precision wavelength scanning mechanisms.A model was established to investigate the impact of grating angle error on the wavelength accuracy of the scanning mechanism.A high-precision encoder based angle error compensation device was designed,and the accuracy correction of the wavelength scanning mechanism was achieved through compensation algorithms designed with different software parameter settings and algorithms;The experimental results show that after compensation through parameter algorithms,the wavelength accuracy and wavelength repeatability accuracy of the scanning mechanism have been improved within the working wavelength range.The degree of accuracy improvement varies under different wavelengths,with an improvement ratio of 20.8% to 35.2% for wavelength accuracy and 61.5% to 95.2% for wavelength repeatability accuracy.The above experimental results verify the effectiveness of the error compensation device and compensation algorithm,improve the accuracy of the wavelength scanning mechanism,and reduce the cost of high-precision wavelength scanning mechanisms in engineering applications.