Experimental measurement of capacity vs. bit error rate for photorefractive holographic storage

A method of measuring capacity vs. bit error rate (BER) for photorefractive holographic storage is presented. The cornerstone of the technique is the measurement of BER with a series of decreasing reference beam powers. The technique allows modulation codes or multiple gray levels to be compared in terms of capacity. Various phase masks, signal processing techniques, and modulation depths can all be compared under realistic conditions. Cross talk can be induced by recording several first holograms. Measuring in the presence of scatter noise and extending the technique to saturable materials are also possible.