Airborne Infrared Transmissometer Design Study, Subsystem Design Analysis Report.
Final rept. Jun 73-Feb 75.
BLOCK ENGINEERING INC CAMBRIDGE MASS
Pagination or Media Count:
This report describes the design of an airborne instrument to measure the transmissivity of the atmosphere to infrared radiation at wavenumber resolutions between 0.5cm to 20cm at ranges between 300 and 50,000 feet. Discussed are the general design approach, the detailed study of that approach, and the development of an instrument based on that study. The instrument uses a Michelson type interferometer to modulate an infrared source and Cassegrainian optics to transmit the signal into the atmosphere. A target mounted retroreflector returns the radiation to receiver optics mounted parallel to and exactly alike the transmitter optics. One of three available detectors senses the total signal and appropriate electronics discriminate the modulated from the unmodulated signal. A Fast Fourier Transform of the resulting interferogram and appropriate geometric scaling result in a high resolution spectrum of atmospheric transmissivity.
- Atmospheric Physics