Accession Number : ADD013406

Title :   Atmospheric Aerosol Extinctiometer.

Descriptive Note : Patent, Filed 2 Sep 81, patented 18 Aug 87,

Corporate Author : DEPARTMENT OF THE AIR FORCE WASHINGTON DC

Personal Author(s) : Stewart, Harold S ; Hansen, Donald F ; Turner, Vernon D

Report Date : 18 Aug 1987

Pagination or Media Count : 12

Abstract : The extinction coefficient of atmospheric aerosol is measured by an instrument in which a single light beam from a graybody source is alternately directed through two similar optical paths to a detector. Each optical path traverses an equal length region of ambient air. Aerosols are filtered from the ambient air region of one optical path. The detector measures the modulation of the incident radiation and its output is a function of the extinction coefficient of the ambient air under test. A second detector is used to monitor the beam power. Processing electronics compute the extinction coefficient of the ambient air under test from the detector outputs. The ambient air regions of the two beam paths are alternately filtered for improved performance.

Descriptors :   *AEROSOLS, *COEFFICIENTS, *EXTINCTION, *PATENTS, *RADIATION ABSORPTION, *INFRARED DETECTORS, AIR, ELECTRONICS, LENGTH, LIGHT, MODULATION, OPTICS, PATHS, POWER, PROCESSING EQUIPMENT

Subject Categories : Atmospheric Physics
      Infrared Detection and Detectors

Distribution Statement : APPROVED FOR PUBLIC RELEASE