Accession Number : ADP006709

Title :   Image-Degradation in a Two-Wave Mixing Spatial-Light Modulator,

Corporate Author : FRIEDRICH-SCHILLER UNIV JENA (GERMANY F R)

Personal Author(s) : Notni, G. ; Kowarschik, R.

Report Date : 22 MAY 1992

Pagination or Media Count : 4

Abstract : Optical real-time image processing by spatial light modulators (SLM's) that utilize photorefractive crystals has attracted much attention. The two-wave mixing SLM is based on the selective spatial erasure of the uniform phase volume hologram created by the two plane coherent beams using an incoherent image bearing beam I sub inc yield above (r) resulting in an additional spatial modulation of the refractive index distribution n sub 1 yield above (r) (commonly with a greater spatial period then the grating period of the hologram). The parameters of these Bragg-type SLM's are strongly determined by the diffraction properties of the nonuniform volume gratings and are analyzed here by means of the two-wave mixing coupled-wave formalism in it's two-dimensional description.

Descriptors :   *IMAGE PROCESSING, *OPTICAL IMAGES, *LIGHT MODULATORS, CRYSTALS, DIFFRACTION, DISTRIBUTION, HOLOGRAMS, IMAGES, INDEXES, LIGHT, LIGHT MODULATORS, MIXING, MODULATION, MODULATORS, NONUNIFORM, PARAMETERS, PHASE, PROCESSING, REFRACTIVE INDEX, UNIFORMS, VOLUME, YIELD, ELECTROOPTICS, SHORT WAVELENGTHS, REFRACTION, SYMPOSIA.

Subject Categories : Optics
      Electrooptical and Optoelectronic Devices

Distribution Statement : APPROVED FOR PUBLIC RELEASE