基于气体吸收谱线宽度的温度检测方法

A Method to Detect Temperature Based on Gas Absorption Spectral Linewidth

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 μm. 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.