Southern California Gas Company

Science Applications Incorporated Corporation

Gordon Dennis Hall

Ervin Roy Bartle, Jr

Michael Griggs

Lawrence Lee Acton

Laurence L Acton

Apparatus is provided which permits highly accurate remote measurement of methane gas concentrations even in daylight through the use of an extremely narrow spectral filter centered on the Q-branch of the methane absorption band at 3.3 microns and through the use of cooperating comparison channels with digital processing for real time correction of data to compensate for surface temperature, atmospheric temperature and atmospheric water absorption factors.

Method and apparatus for accurate remote monitoring of gases

A method for remotely monitoring the concentration of a particular gas species in a gaseous mixture. The remote detection of pollutants emitted in source effluents, e.g., gas from a smokestack, involves specific spectral measurements of infrared radiation and, in this method, includes ratioing the signals from two gas-reference cell pairs to eliminate dependencies upon the inlowering atmosphere and source effluent temperature. An instrument cell construction and assembly using a unique cells-within-a cell permits use of a single lens that insures common fields-of-view for both cell pairs; a triple chopping system uses tuning forks to alternately pass the incoming energy through the gas and reference cells eliminating the need for separate sync signal generators, and provides a high carrier frequency improving the signal-to-noise ratio of the sensor.

Growing community of inventors

San Diego, CA, United States of America

Gordon Dennis Hall