Gas detection method and system based on optical phase amplification

Abstract

The invention relates to the field of gas detection, in particular to a gas detection method and system based on optical phase amplification. Gas to be detected absorbs heating laser to generate heat, and the generated heat can be used to modulate the phase of detection laser; photo-thermal phase modulation on the detection laser is amplified by an optical resonant cavity; and the phase of the detection laser emitted from the optical resonant cavity is measured and analyzed to obtain the parameters of the gas to be detected. According to the invention, tiny photo-thermal phase modulation on the detection laser can be effectively amplified, and the signal-to-noise ratio of detection is improved. According to the invention, trace gas parameter detection with a volume fraction detection lower limit of one trillion magnitude can be realized, and the method has universality for absorbing gases in visible light wave bands, near-infrared wave bands and middle-infrared wave bands. 本发明涉及气体检测领域，具体是涉及一种基于光学相位放大的气体检测方法和系统。本发明通过待检测气体吸收加热激光而产生热量，产生的热量能够调制探测激光的相位；探测激光受到的光热相位调制经光学谐振腔放大；对从光学谐振腔出射的探测激光的相位进行测量并分析以获取待检测气体的参数。本发明可以有效地将探测激光受到的微小的光热相位调制进行放大，提高检测的信噪比。本发明可实现体积分数检测下限为万亿分之一量级的痕量气体参数检测，本发明对能够吸收可见光波段、近红外波段以及中红外波段的气体具有普适性。