基于红外检测的H_2S传感器中光谱吸收的理论

Spectrum Absorption Theory about H_2S Sensor Based on Infrared Detecting Technology

对于光纤红外的方法检测污染气体的浓度,光谱吸收理论具有非常重要的意义。根据朗伯-比尔(Beer-Lambert)理论,首先从硫化氢(H2S)气体浓度的定量分析以及分子参数的理论进行研究,再通过分析该气体的吸收线得出该气体的吸收系数α(ν)的一般方法。并得到,在气体压强小于0.03个标准大气压(atm,1atm=1.01325×105Pa)时用高斯(Gaussian)线型拟合,大于2atm时用洛伦兹(Lorentzian)线型拟合,它们的相对误差都控制在小于0.1的范围之内。压强在0.03—2atm之间时,吸收线型用福赫特(Voigt)线型拟合比较好,理论上得到很好的结果。

The spectrum absorption theory has the very important significance for determination of concentration of polluted gas by optical fiber.According to Beer-Lambert theory,quantitative analysis of H2S gas concentration and molecular parameters theory were firstly investigated,then the common method for absorption coefficient of H2S gas was obtained from the absorption line of H2S gas.When the gas pressure is lower than 0.03atm（1atm=1.01325×105Pa）,Gaussian alignment fitting is chosen,the gas pressure is higher than 2 atm,Lorentzian alignment fitting is chosen.and their relative error were controlled in the range of 0.1.In addition,when the gas pressure is between 0.03 and 2 atm,Voigt alignment fitting will do better.In theory was obtained a very good result.