Gas species monitor system

摘要

A gas species monitor system includes a sample volume for receiving a gas to be monitored; an external, independent laser source; means for directing the laser radiation to the volume; a multipass optical cell, responsive to the means for directing, for multiplying the laser radiation intensity in the sample volume; means for continuously flowing the gas to be monitored through the sample volume; a narrow bandpass filter; means for collecting more than a steradian of Raman scattered radiation from the sample in the volume and directing the collected radiation in parallel through the narrow bandpass filter; and means responsive to the parallel radiation from the filter for detecting the Raman scattered radiation representative of the concentration of the species in the gas sample being monitored.