Transmission of Infrared Materials and Condensed Gases at Cryogenic Temperatures
Abstract
An infrared optical transmission chamber was developed to measure the spectral transmission of cryogenically cooled (20 K and 80 K) optical windows, filters, etc., both with and without cryodeposit contamination. An FTS-14 Interferometer Spectrometer recorded transmission measurements for 20 and 80 K germanium windows both clean and with the following contaminants condensed on them: NH3, CO2, CO, CH4, HC1, and air. These measurements were made for many different contaminant thicknesses. From 20 and 80 K data the optical constants (complex refractive index) for NH3 were determined. Further, the transmission measurement of 20 and 80 K polystyrene was recorded and showed that the standard absorption bands observed at 300 K not shift in wavenumber more than 1/cm when the polystyrene is cooled to 20 K. Hence, polystyrene is a reliable wavelength calibrator when used at 20 K.
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 01, 1977
- Accession Number
- ADA044517
Entities
People
- A. Matthew Smith
- H. E. Scott
- J. A. Roux
- J. G. Pipes
Organizations
- Arnold Engineering Development Complex