Accession Number : ADA954092

Title :   Production of Infrared Transmitting Thallium Halide Crystals.

Descriptive Note : Interim rept.,

Corporate Author : ARMY ENGINEER RESEARCH AND DEVELOPMENT LABS FORT BELVOIR VA

Personal Author(s) : Botzenmayer,P. C. , Jr. ; Ashcroft,J. M. ; Smakula,A.

Report Date : 08 OCT 1948

Pagination or Media Count : 49

Abstract : This interim report covers an investigation to develop methods and techniques for producing large, single crystals from a mixture of two thallium halides. Such crystals constitute a raw material from which lenses, windows, and prisms may be fabricated for use in far (wave lengths in the range from approximately 2 to 40 microns and above) infrared optical systems. This report includes a detailed description of the process used in producing the thallium salts, the physical plant, and the techniques employed in growing the crystals. The crystals were produced from mixtures of thallium halide salts which were prepared by precipitating the halides from an acidified solution of thallous sulfate. The crystals were grown by crystallizing a melt of the salt mixture in furnaces of the Stockbarger type. It is concluded from these investigations that to grow thallium halide crystals suitable for infrared optics, by the Stockbarger method, two exacting conditions must be fulfilled: The salts from which the crystals are grown must be of very high purity; and A thermal equilibrium, constant within very narrow limits, must be maintained.

Descriptors :   *INFRARED OPTICAL MATERIALS, *HALIDES, *THALLIUM COMPOUNDS, *SINGLE CRYSTALS, CRYSTAL GROWTH, PRECIPITATION, FURNACES, INFRARED OPTICAL SYSTEMS, MIXTURES, SALTS, PRODUCTION

Subject Categories : Crystallography
      Optics

Distribution Statement : APPROVED FOR PUBLIC RELEASE