Hologram memory apparatus

DETAILED DESCRIPTION What is claimed is: 1.
A hologram memory apparatus for recording information as one-dimensional holograms, comprising: optical source means for producing a coherent light beam; beam splitter means for dividing the coherent light beam into at least one signal light beam and a reference light beam; first optical means having a common optical axis for said at least one signal light beam and said reference light beam for focusing said light beams into parallel beams, said focused reference light beam being spaced from said focused at least one signal light beam by a distance of slightly greater than L/2; light switch means for intercepting said at least one signal light beam and controllably transmitting a plurality of linearly arrayed signal light beams corresponding to information to be recorded, said light switch means having a length L; polarization controlling means for spatially dividing said light switch means into two L/2 regions wherein the electric vectors of the contiguous transmitted signal light beams of one region intersect the electric vectors of the contiguous transmitted signal light beams of the other region orthogonally, the electric vector of said reference light beam being at 45.
degree.
to each of the electric vectors of the transmitted signal light beams from said two regions; memory means having a surface in which said one-dimensional holograms are to be recorded; and second optical means having a common optical axis for said transmitted signal light beams and said reference light beam for focusing said light beams on the surface of said memory means to form interference patterns, the aperatures of said first and second optical means being on the order of 3/2 L.
-- 2.
A hologram memory apparatus as recited in claim 1 further comprising: one-dimensional photo-detector means for generating an electric signal corresponding to an image illuminated thereon; and third optical means for focusing on said one-dimensional photo-detector means an image of information reproduced by illuminating one-dimensional holograms recorded on said memory means with said reference light beam