R&D Report 1979-14 : Digital recording using hologram arrays: optical design for an experimental 100 Mbit/s recorder. K. Hacking, J.L. Riley
The general arrangements used in the construction of an experimental recorder are outlined and several optical design features of the proposed system are discussed in detail. These include the concepts underlying the design of a digit-beam array forming a hologram 'page' and the optical methods for recovering the digital information. The optimum dimensions of the various optical components are derived from theoretical considerations based on the performance requirements. A brief description of an experimental record and replay apparatus intended for feasibility tests is given, together with some measurements of the optical transmission efficiencies achieved. These results were lower than anticipated and emphasise the need to use high quality optical components and eliminate surface reflection losses.