Accession Number : ADD003435

Title :   Photodichroic Readout Device Using Circularly Polarized Light.

Descriptive Note : Patent,

Corporate Author : DEPARTMENT OF THE NAVY WASHINGTON D C

Personal Author(s) : Burt,James Vinton

Report Date : 20 Jan 1976

Pagination or Media Count : 6

Abstract : A unique photodichroic readout device is composed of photodichroic material thru which is passed a circularly polarized light beam that is horizontally or vertically polarized dependent upon the storage of information in the material. The beam is then passed to a beam splitter which segregates the horizontal polarized light and the vertical polarized light. The two individual beams pass to individual detectors whose output is coupled to a difference amplifier. The system also provides a method for selectively storing information within the photodichroic material. The memory element employed is the M(A) color center in KCl:NaCl. Although this material is not as ideal as the M center in NaF in that it must be kept at 77K in order to stabilize the centers, the factors that it is extremely well studied and that the exciting wavelength is in the visible are determining for the initial embodiment.

Descriptors :   *Patents, *Optical storage, *Memory devices, *Photochromic materials, Color centers, Polarization, Dichroism, Sodium chloride, Potassium chloride

Subject Categories : Computer Hardware
      Optics

Distribution Statement : APPROVED FOR PUBLIC RELEASE