FAR--INFRARED INTERFEROMETRIC MODULATION AT THE JOHNS HOPKINS UNIVERSITY
Loading...
Date
1959
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Ohio State University
Abstract
Interferometric modulation is a technique for obtaining spectral information in the far-infrared region of the spectrum, where detector noise limits the resolution that tan be obtained with diffraction gratings. The observations consist of obtaining a plot of the illumination resulting from the interference of two coherent beams of radiation as a function at their path difference. The transformation from observed data to spectra is discussed, and the ``scanning’‘ function for an interferometric modulator, similar to the diffraction grating ``scanning’‘ function, is arrived at. The resolving power to be expected from this interferometric technique is shown to be proportional to the maximum path difference between the interfering beams, the lamellar-grating type interferometer and auxiliary apparatus is described. Far-infrared spectra, obtained with the instrument, $indicating = (1/4] cm^{-1}$ resolution, are presented.
Description
Author Institution: Laboratory of Astrophysics Physical Meteorology, The Johns Hopkins University