基于气体吸收谱线宽度的温度检测方法

摘要

本文提出一种用于温度传感的气体吸收谱线宽度检测方法,该方法基于比尔-朗伯定律中气体吸收谱线宽度与温度关系,以特征线宽代替半高全宽(FWHM)进行线宽的测量.研究气体所处环境的温度改变对气体吸收谱线宽度的影响.以乙炔气体为例,在0～90℃的温度范围内,测量了其5条较强吸收谱线的特征线宽变化情况.特征线宽测量值标准差<0.6 pm,温度分辨力<2℃,稳定性好.此方法有效避免了光源功率的波动对特征线宽测量的影响,提高了线宽测量的准确性,该方法应用于气体温度测量具有可行性.%This paper proposes a method to detect the linewidth of gas absorption spectra for temperature sensing, which is based on the relationship between gas absorption spectral linewidth and temperature ac-cording to the Beer-Lambert Law, introducing the typical linewidth instead of the full width at half maxi-mum ( FWHM) to measure the spectral linewidth.While temperature varied, we measured the typical linewidths to obtain the relationship between them.Taking acetylene as an example, we measured the typical linewidths changing with tempurature of 5 absorption lines.In this process, the temperature varied within 0—90 ℃, and the maximum typical linewidth standard deviation is 0.6 pm.The temperature res-olution is <2 ℃.This method avoids the laser power fluctuation influencing on temperature, which im-proves the accuracy in linewidth measurement and makes it possible to apply it to the measurement of gas temperature.