Based on results of diffraction theory, it is shown that the proportions of storage plate and detector matrix, respectively, page-composer, of a fast holographic mass memory are strongly coupled. A high capacity fast data store needs a large detector array. Optimized geometry results if storage plate and detector matrix have the same size. A square detector matrix, able to read about 1010 bits in an optimum designed memory, should have a diagonal extension of about 1 m.
P. Graf and M. Lang, "Geometrical Aspects of Consistent Holographic Memory Design," Appl. Opt. 11, 1382-1388 (1972)