Accession Number : ADA118314

Title :   Spectroscopic Study of Small Absorptions in Optical Coatings.

Descriptive Note : Final rept.,

Corporate Author : UTAH STATE UNIV LOGAN

Personal Author(s) : Hansen,Wilford N

PDF Url : ADA118314

Report Date : Jul 1982

Pagination or Media Count : 58

Abstract : This report concerns research performed by the Utah University surface physics group for the Air Force Weapons Laboratory (AFWL), Kirtland Air Force Base, New Mexico. It is a supplement to AFWL-TR-79-197. It reports the continued study of thorium fluoride (ThF4) as an optical coating, showing that the moisture found in the ThF4 films probably originated from the preparation itself, and that ThF4 may not degrade by moisture absorption from the atmosphere as rapidly as previously thought. Further advances are reported in the characterization procedures themselves, including computer methods for data handling. New procedures were instituted for determining the optical constants of liquids. To test the procedures, the optical constants of liquid water were determined and compared with values found in literature. The procedures used are reported. A sample of Si3N4 film on germanium was analyzed spectroscopically. The dominant feature was a large infrared band revealing the presence of large amounts of silicon hydride. Finally, new procedures are reported for determining impurity concentrations in optical thin films which takes into account the local electromagnetic field strength seen by an impurity in a known optical material as matrix. (Author)

Descriptors :   *Optical coatings, *Thin films, *Absorption, *Spectroscopy, Lasers, Fluorides, Thorium compounds, Silicon nitrides, Hydrides, Optical properties, Constants, Liquids, Water, Absorption spectra, Impurities, Concentration(Composition), Lorentz Force

Subject Categories : Lasers and Masers
      Coatings, Colorants and Finishes
      Optics

Distribution Statement : APPROVED FOR PUBLIC RELEASE