Patent ID: 7372573
Filing Date: 2008-05-13
Classification: G01N

Abstract:
1. An apparatus capable of measuring a trace gas, comprising: a source of a first beam of radiation; an interferometer receiving the first beam of radiation from the source and forming a second beam of radiation comprising an interference signal; a sample cell in optical communication with the interferometer, the sample cell comprising: a flow mechanism establishing a flow of a sample of gas through the sample cell; a cooled detector in optical communication with the sample cell, the cooled detector receiving the interference signal propagating through the sample in the sample cell; a processor in electrical communication with the cooled detector, the processor determining from the interference signal an absorption profile for a trace gas in the sample; and a housing in which the source, the interferometer, the sample cell, the cooled detector and the processor are disposed; wherein the volume of the sample cell and the number of reflections of the second beam of radiation are optimized to detect a trace gas having a concentration of less than about 500 ppb in the sample of ambient air.