Optical Components For Infrared And Submillimeter Wave Cryogenic Remote Sensors

Abstract

The spectroscopic instruments that will go into space aboard the Cosmic Background Explorer (COBE) satellite cover the electromagnetic spectrum from 1μm to about 10cm in wavelength. Two of the instruments - the Far Infrared Absolute Spectrometer (FIRAS) and the Diffuse Infrared Background Experiment (DIRBE) - will operate at temperatures below 10K. The combined challenges of broad wavelength coverage and low temperature operation drove component design across several technology frontiers in both spectral and temperature regimes. This report will discuss the design and test of the filters, polarizers and dichroic beamsplitters that have been selected to satisfy the cryogenic sensor performance requirements in response to the broad wavelength and temperature demands.