针对微型紫外光谱仪应用设计要求,开展了紫外光谱仪系统研究,完成了IV型光学系统设计。研制出在线实时分析的微型紫外光谱仪,对样机主要参数的测试表明:其工作波长为200~400 nm,分辨率达0.31 nm,波长准确性为±0.1 nm,信噪比为507∶1。通过12 h系统稳定性测试,结果表明该样机光谱波动小于0.47%,达到了光谱仪长期工作的稳定性要求。在25 ℃的实验条件下通过SO2气体对光谱仪性能进行测试,基于差分吸收光谱技术理论,完成了标准气体的差分吸收截面计算。通过连续24 h对质量浓度为20~100 mg/m 3的SO2进行测试,结果表明光谱仪测试数据反演质量浓度的波动性小于1%,线性误差小于0.6%,最大示值误差为-0.56 mg/m 3。

In this study, a micro-ultraviolet spectrometer with an IV-type optical system is designed, fabricated, and analyzed. The micro-ultraviolet spectrometer is effectively validated for online real-time analysis applications. The main parameters of the prototype include a wavelength range of 200-400 nm, resolution of 0.31 nm, wavelength accuracy of ±0.1 nm, and a signal-to-noise ratio of 507∶1. The experimental results of a 12-h system stability test suggest that the spectral fluctuation is less than 0.47%, confirming the long-term stability of the spectrometer. Finally, the performance of the spectrometer is verified by measuring SO₂ gas at 25 ℃. Based on the theory of differential absorption spectroscopy, a differential absorption cross section calculation of a standard gas is performed. The test results show that the inversion mass concentration of the spectrometer test data has a fluctuation of less than 1%, linearity error of less than 0.6%, and maximum indication error of -0.56 mg/m ³ upon testing an SO₂ mass concentration of 20-100 mg/m ³ for 24 h.