光学学报, 2018, 38 (12): 1214001, 网络出版: 2019-05-10
一种单光谱吸收积分吸光度快速计算方法及应用 下载: 1535次
A Fast Calculation Method of Single Spectral Absorption Integral Absorbance and Its Application
光谱学 可调谐半导体激光吸收光谱技术 Voigt线型拟合 三角替代方法 高斯-埃尔米特方法 spectroscopy tunable diode laser absorption spectroscopy Voigt linetype fitting triangular fitting method Gauss-Hermite method
摘要
可调谐半导体激光吸收光谱技术(TDLAS)作为一种痕量气体精确检测的方法,已广泛应用于生活生产之中,该方法可通过积分吸光度与气体浓度的线性关系准确反演待测气体的浓度。环境变化和系统噪声等易造成吸光度曲线发生变形,故需对吸光度曲线进行非线性拟合,将其回归至Voigt模型。设计并搭建了基于TDLAS的CO实时在线监测系统,在此平台基础上,提出了一种三角替代Voigt线型单光谱积分吸光度的快速计算方法,并与高斯-埃尔米特方法进行比较。结果表明:三角替代方法浓度反演精度仅下降0.11%,平均计算耗时缩短84.19%;三角替代Voigt线型拟合方法以极小的精度损失,大幅提高了线型拟合的运算速度。
Abstract
Tunable diode laser absorption spectroscopy (TDLAS), as an accurate detection method for the trace gases, has been widely used in the life and production. It can accurately inverse the gas concentration through the linear relation between the integral absorbance and the gas concentration. The changes in the environment and the system noise tend to cause the deformation of the absorbance curve. Therefore, it is necessary to do the nonlinear curve fitting on the absorbance curve to make it return to the Voigt model. A real-time online monitoring system for carbon monoxide based on TDLAS has been designed and built. With the platform, a fast calculation method with the triangular Voigt linetype fitting for the single spectral integral absorbance has been put forward and compared with the Gauss-Hermite method. The accuracy of the proposed method is only 0.11% lower, but the average computation time is shortened by 84.19%. The experimental results show that the triangular Voigt linetype fitting method can greatly improve the fitting speed only with the minimal accuracy loss.
鲁一冰, 刘文清, 张玉钧, 张恺, 余冬琪. 一种单光谱吸收积分吸光度快速计算方法及应用[J]. 光学学报, 2018, 38(12): 1214001. Yibing Lu, Wenqing Liu, Yujun Zhang, Kai Zhang, Dongqi Yu. A Fast Calculation Method of Single Spectral Absorption Integral Absorbance and Its Application[J]. Acta Optica Sinica, 2018, 38(12): 1214001.