초록 ▼

A method and apparatus for remote detection of gas leak and determination of the relative concentration of a gas using nondispersive infrared absorption of backscattered laser light with background compensation. The method includes source of coherent infrared radiation, sealed reference cell, filled

A method and apparatus for remote detection of gas leak and determination of the relative concentration of a gas using nondispersive infrared absorption of backscattered laser light with background compensation. The method includes source of coherent infrared radiation, sealed reference cell, filled with air with admixture of reference gas of known concentration, sealed control cell filled with air, sensitive elements which are sensitive to radiant fluxes in a determined band of wavelengths. The method includes measuring output signals, calculating the difference of the signals from control cell for different points, the difference of signals from reference cell and control cell, the ratio of said differences and relative concentration, and means for converting said concentration into visual image and audio signal. The apparatus includes camera or video camera to record a visual image of an object at the point where the maximum relative concentration was recorded and laser pointer to indicate a position of invisible infrared beam on a target.

대표청구항 ▼

[ I claim:] [1.] Method for detecting the presence of a gas leakage, comprising:irradiating the area of a possible leak with infrared laser radiation at a single wavelength, which is absorbed by the gas and backscattered or reflected from the irradiated area;detecting backscattered laser radiation f

[ I claim:] [1.] Method for detecting the presence of a gas leakage, comprising:irradiating the area of a possible leak with infrared laser radiation at a single wavelength, which is absorbed by the gas and backscattered or reflected from the irradiated area;detecting backscattered laser radiation from the irradiated area;continuous processing of the detected signals from two cells of identical configuration;continuous calculation of differential signals, their ratios, and relative concentrations;producing a visual image and audio signal related to the said relative concentrations when the gas is present in said irradiated area.