Accession Number : AD0163973

Title :   Photoelement Intense Radiation Protective Device.

Descriptive Note : Patent,

Corporate Author : DEPARTMENT OF THE NAVY WASHINGTON D C

Personal Author(s) : Finvoid,Rodger C. ; Davis,Charles M.

Report Date : 30 JAN 1973

Pagination or Media Count : 5

Abstract : The patent describes an optical detector protective device for a radiation detecting system. It consists of a filter of direct-band-gap emitting semiconductor material, which has an extremely steep absorption edge as compared to indirect band-gap materials and a spectral filter for passing desired bandwidth. The absorption edge of the direct-band-gap filter is adjacent to its emitting line and positioned such as to pass the desired emission line at ordinary temperatures and attenuate the emission line at elevated temperatures. The device prevents deterioration of the detector in the presence of high intensity light sources in cases where monochromatic or near monochromatic light is employed. The absorption coefficient of the device varies greatly with temperature and wave length.

Descriptors :   (*OPTICAL FILTERS, *PATENTS), (*RADIATION MEASURING INSTRUMENTS, PROTECTION), SEMICONDUCTORS, LENSES, GALLIUM ARSENIDES

Subject Categories : Optics

Distribution Statement : APPROVED FOR PUBLIC RELEASE