基于宽波段激光吸收谱的真空分压力测量方法  

Vacuum Partial Pressure Measurement Method by Means of Broad-Bandwidth Laser Absorption Spectrum

作　　者：代虎[1] 王永军[1] 李得天[1] DAI Hu;WANG Yongjun;LI Detian(Science and Technology on Vacuum Technology and Physics Laboratory,Lanzhou Institute of Physics,Lanzhou 730000,China)

机构地区：[1]兰州空间技术物理研究所真空技术与物理重点实验室

出　　处：《真空与低温》2020年第1期37-41,共5页Vacuum and Cryogenics

基　　金：真空技术与物理国家级重点实验室开放的基金资助项目(ZWK1802);航天科技集团自主研发项目支持

摘　　要：为了弥补质谱法测量分压力的诸多原理性缺陷和调谐二极管激光吸收谱法(TDLAS)的不足,提出了基于双光梳外差光谱技术的激光吸收谱真空分压力测量方法。利用双光梳光谱仪工作波段宽、光谱分辨率高和测量速度快的优势,辅以多通池样品腔增加有效吸收长度,实现非侵入式、高速度和高精度的真空分压力测量。利用CH 4在3.3222~3.4130μm波段的32个特征吸收峰分别测量CH 4的分压力,测量结果中最大相对偏差为5.45%,均值分压力的偏差为0.85%。经过不确定度估算分析,分析结果与测量结果较为一致。利用目标气体N个特征吸收峰分别反演计算分压力后等权平均,可以明显降低真空分压力的测量不确定度,降低系数约为1 N。In order to overcome the many principle defects of mass spectrometry and make up the deficiencies of TDLAS method,a laser absorption spectrum vacuum partial pressure measurement method based on dual-comb heterodyne spectroscopy was proposed.The advantages of the dual-optical comb spectrometer,such as broad band width,higher spectral resolution and fast measurement speed,are used to achieve non-invasive,high-speed,high-precision vacuum partial pressure measurement with aid of the multi-pass sample chamber that was utilized to increase the effective absorption length.The partial pressure of CH 4 was measured by 32 characteristic absorption peaks of CH 4 in the range of 3.3222 to 3.4130μm.The maximum relative deviation in the measurement results was 5.45%,and the deviation of the average partial pressure was 0.85%.Through the uncertainty estimation analysis,the measurement results were consistent with the uncertainty analysis results.By fitting the N characteristic absorption peaks of the target gas and calculating the Average partial pressure,the measurement uncertainty of the vacuum partial pressure could be significantly reduced,and the reduction coefficient was about 1 N.

关 键 词：真空分压力 激光吸收谱 双光梳外差光谱仪 吸收峰拟合 

分 类 号：TB771[一般工业技术—真空技术]