Low-absorption laser windows. Semiannual report No. 1, for period ending 31 Dec 1975

Technical Report · Thu Apr 01 04:00:00 EST 1976

OSTI ID:7342992

Klein, P H

This semiannual report summarizes work by NRL under ARPA Order 3066. Improvements have continued in methods for preparation, surface finishing, and characterization of low-loss laser-window materials. Calorimetric absorption studies included measurements of eight alkali and alkaline earth halides at 1.06 micrometers and of calcium fluoride, zinc selenide, and several alkali halides at 2.7, 3.8, and 10.6 micrometers. Adequate surface preparation virtually eliminates detectable surface absorption. Carbon tetrachloride is the most effective reactive halide for purification of potassium bromide. A polishing method analogous to that for KCl was found effective for KBr, resulting in pit-free surfaces stable to room air for over a week, especially for surfaces remote from cleavage planes. Appended to this report is an abstract of a Navy-sponsored paper which compares crack propagation in alkali halides with that in alkaline earth fluorides. Future studies (for which some crystals have been prepared) will involve purification of strontium fluoride, additive strengthening of potassium chloride and potassium bromide, and testing of an evacuated calorimeter. (GRA)

• Research Organization: Naval Research Lab., Washington, D.C. (USA)
• OSTI ID: 7342992
• Report Number(s): AD-A-024018; NRL-MR-3266
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360601 -- Other Materials-- Preparation & Manufacture
42 ENGINEERING
420300* -- Engineering-- Lasers-- (-1989)
ALKALINE EARTH METAL COMPOUNDS
CALCIUM COMPOUNDS
CALCIUM FLUORIDES
CALCIUM HALIDES
CHALCOGENIDES
FABRICATION
FLUORIDES
FLUORINE COMPOUNDS
HALIDES
HALOGEN COMPOUNDS
LASER MATERIALS
LASERS
OPENINGS
SELENIDES
SELENIUM COMPOUNDS
WINDOWS
ZINC COMPOUNDS
ZINC SELENIDES