Halographic process for the real-time storage and retrieval of high speed digitally encoded information and an apparatus for implementing said process

摘要

The process consists in splitting the information into N groups of M bits, in recording the groups on N parallel tracks on the carrier, in the form of M holograms differentiated from each other by the pitch of the interference fringes constituent of each hologram. To this end, either a laser of variable wavelength is used, or a reference beam of variable direction. The M holograms are superimposed. At the play-back stage, a fixed coherent light beam projected onto one hologram generates NM beams of different directions. N rows of M photodiodes detect the beams and supply read-out means.