Accession Number : ADP008270

Title :   Incoherent Light Read-Out of Spectral Holograms,

Corporate Author : CENTRE NATIONAL DE LA RECHERCHE SCIENTIFIQUE ORSAY (FRANCE)

Personal Author(s) : Debarre, A. ; Keller, J. C. ; Le Gouet, J. L. ; Tchenio, P.

Report Date : 22 MAY 1992

Pagination or Media Count : 3

Abstract : It is known that one has investigated two types of approach to Persistent Spectral Hole Burning (PHB), and to potential application for optical data storage. In both methods, a structure is stored within the inhomogeneously broadened optical absorption line of the guest ions or molecules in a host matrix at low temperature. In the first method, monochromatic laser irradiation results in the reduction of the sample absorption coefficient at a given frequency. The burnt spectral hole is then detected by monitoring the transmission of the laser beam when its frequency is scanned over the absorption band. In view of application to optical data storage, spectral hole burning can be regarded as the physical process for addressing a bit of binary encoded information at a position within the absorption band. The maximum number of independent addresses in the absorption band is given by the ratio between the inhomogeneous width delta I and the homogeneous width delta h of the optical transition.

Descriptors :   *OPTICAL DATA, *STORAGE, *INCOHERENCE, *LIGHT, *READ OUT TECHNIQUES, *SPECTRA, *HOLOGRAMS, ABSORPTION, ABSORPTION COEFFICIENTS, ADDRESSING, APPROACH, COEFFICIENTS, FREQUENCY, IONS, IRRADIATION, LASER BEAMS, LASERS, LOW TEMPERATURE, MOLECULES, MONITORING, NUMBERS, RATIOS, REDUCTION, STRUCTURES, TEMPERATURE, TRANSITIONS, WIDTH, HOMOGENEITY, DETECTION, MEMORY DEVICES, COMPUTERS, BINARY NOTATION, CODING, INFORMATION PROCESSING, SPECTROSCOPY, PHOTONS, CROSS CORRELATION, OPTICS, IMAGES, MOLECULAR SPECTROSCOPY.

Subject Categories : Computer Hardware
      Test Facilities, Equipment and Methods
      Optics
      Electrooptical and Optoelectronic Devices

Distribution Statement : APPROVED FOR PUBLIC RELEASE