The absolute solar transmittance interferometer measures absolute solar radiance at the Earth’s surface. The instrument is based on a Fourier-transform spectrometer that utilizes a liquid-nitrogen-cooled InSb detector and appropriate optical bandpass filters. The recorded solar spectra are calibrated against National Institute of Standards and Technology traceable lamps and a blackbody source. The spectral range addressed by this instrument is from 1950 to 10100 cm<sup>−1</sup> at a resolution of 2 cm<sup>−1</sup>. The optical design of the instrument and the experimental methods are discussed. A discussion of the uncertainties involving the instrument and the calibration sources is presented. Initial measurements from several sites are compared with atmospheric model calculations.
© 2002 Optical Society of America
(070.2580) Fourier optics and signal processing : Paraxial wave optics
(120.4640) Instrumentation, measurement, and metrology : Optical instruments
(280.1120) Remote sensing and sensors : Air pollution monitoring
(280.1310) Remote sensing and sensors : Atmospheric scattering
(300.6340) Spectroscopy : Spectroscopy, infrared
Toufic Hawat, Thomas Stephen, and Frank Murcray, "Absolute Solar Transmittance Interferometer for Ground-Based Measurements," Appl. Opt. 41, 3582-3589 (2002)