DEVICE WITH MULTIBEAM SPECTRAL FILTER FOR DETECTING METHANE IN ATMOSPHERE Russian patent published in 2017 - IPC G01N21/31 G01J3/18 

FIELD: measuring equipment.

SUBSTANCE: device includes featured in the general case and an optically connected emitter of the radiating light beam with a continuous spectrum, a diffractive element, forming a parallel beam of radiation of optical elements, a transparent cuvette, optical elements that transmit the past of the parallel beam on the lens, a photodetector, a system of registration and processing the received electric signal, a power supply and control device. The diffractive element is made in the form of a Fresnel lens with a variable width of concentric annular confocal lenses, the number of which is determined by the ratio of the spectral interval width between the lines of the vibrational-rotational spectrum of methane to the width of these lines. Between the diffractive element and the optical elements forming the parallel beam of radiation, an optical device for controlling the amplitudes of the light signals is arranged in the form of a spatially inhomogeneous filter with a transmission different for each of the annular elements of the Fresnel lens.

EFFECT: increasing the sensitivity and accuracy of measurements.

14 dwg