Accession Number : AD0785274

Title :   Investigation of a Photodichroic Material for Holographic Storage and Recovery.

Descriptive Note : Annual technical rept. Sep 73-Aug 74,


Personal Author(s) : Lehmann,Matt ; Armistead,R. A.

Report Date : AUG 1974

Pagination or Media Count : 30

Abstract : The effect of impurities on the formation of color centers in the photodichroic crystals of sodium fluoride and on the fatigue of the write/read cycles has been examined. The results of this effort suggest that lithium ion implantation is the only satisfactory method for producing controllable color center depth with optimum fluence. There is now a need to determine the optimum ion for implantation in potassium chloride and other alkali halides that are candidates for information storage. Controlled depth of color centers is essential to maintain satisfactory resolution with high orders of minification. A unique procedure was developed giving major improvements in effective writing sensitivity. This procedure, which uses a readout system with crossed polarizers, gives high contrast, high resolution images and also permits the photodichroic alkali halide to be used as the storage medium in an incoherent/coherent processor. (Modified author abstract)

Descriptors :   *Photochromism, *Data storage systems, Electrooptics, Sodium compounds, Potassium compounds, Chlorides, Fluorides, Doping, Lithium, Color centers, Polarization, Ion implantation

Subject Categories : Computer Hardware
      Printing and Graphic Arts

Distribution Statement : APPROVED FOR PUBLIC RELEASE