Phase-coded hologram multiplexing for high capacity optical data storage

Reconfigurable volume holograms are important for a wide range of multiple data storage applications, including optical interconnection systems, image processing and neural network models. Therefore, there has been much previous work on multiplexing techniques to obtain a large number of stored images which can be recalled independently. But even the most promising of these multiplexing techniques, angular multiplexing using the selectivity of the Bragg-condition, revealed to be limited primarily because of cross-correlation noise. Moreover, mechanically changing the incident angle of the reference beam1,2 requires a high reliability in the positioning and is therefore inherently slow. To overcome these problems, an intensity spatial light modulator can be used to define the various angular multiplexed incident directions3.