Accession Number : AD0914194

Title :   Development of Deicing Methods for Chalcogenide Windows for Reconnaissance and Weapon Delivery.

Descriptive Note : Final rept. 1 Mar 72-31 Jul 73,

Corporate Author : TEXAS INSTRUMENTS INC DALLAS EQUIPMENT GROUP

Personal Author(s) : Rea, Samuel N. ; Wriston, Robert S.

Report Date : OCT 1973

Pagination or Media Count : 39

Abstract : A limited number of infrared transmitting materials are suitable for external windows in airborne systems operating in the 8- to 14-micrometers wavelength region. Of the common window materials available in this region, only germanium can be made intrinsically conductive to the point where it can be electrically heated to prevent icing. Other IR window materials such as ZnS, ZnSe, GaAs, and the chalcogenide glasses must be provided external heating in the form of resistive wires, conductive coatings or forced hot air to achieve deicing. The various techniques examined for deicing chalcogenide glasses are described in this report. Chemical vapor deposited ZnS was examined briefly with regard to using resistive wires patterned on the surface to achieve deicing. Results of this study indicate that resistive wires deposited on the glass surface and conductive coatings of various indium-oxygen combinations can achieve deicing of external IR windows although neither technique is completely satisfactory for chalcogenide glass windows under worst case icing conditions. However, these techniques show considerable promise for deicing windows made from materials having higher thermal conductivities than the chalcogenide glasses.

Descriptors :   *DEICING SYSTEMS), (*INFRARED WINDOWS, (*DEICING MATERIALS, COATINGS), CHALCOGENS, GERMANIUM, GALLIUM ARSENIDES, ZINC COMPOUNDS, SELENIUM COMPOUNDS, SULFIDES, ELECTRICAL CONDUCTIVITY, OPTICAL GLASS, REFRACTIVE INDEX, TEMPERATURE, HEATING, HEAT FLUX, AIR, WIRE, TIN COATINGS, INDIUM COMPOUNDS, OXIDES, INFRARED RADIATION, AIRBORNE, SPUTTERING, THERMAL CONDUCTIVITY.

Subject Categories : Coatings, Colorants and Finishes
      Optics

Distribution Statement : APPROVED FOR PUBLIC RELEASE