Optical feedback resonant optical cavity system suitable for the detection of gas traces by Raman spectrometry

摘要

Optical feedback resonant optical cavity system suitable for detecting gas traces by Raman spectrometry The invention relates to a method for analyzing gas by Raman spectrometry, the method comprising the steps of: generating by a laser source (100) a laser beam scanning a range of frequencies including frequencies of several resonance modes of an optical cavity (180) including gases to be analyzed, delivering the laser beam to an input (182) of the optical cavity, extracting from the optical cavity a feedback beam which is sent adjusted in phase and amplitude to the laser source, during the scanning of the frequency range, to detect peaks of light intensity (221-229) in the laser beam in the optical cavity wherein the phase of the feedback beam is adjusted to reduce asymmetries in the shape of the peaks, the amplitude of the feedback beam is adjusted to reduce intervals of zero intensity between peaks, and perform a spectral analysis of the light scattered inelastically in the optical cavity, to determine the composition of the gases in the optical cavity. Figure for the abstract: Fig. 1