WRITING AND COPYING IN VOLUME HOLOGRAPHIC MEMORIES - APPROACHES AND ANALYSIS

We analyze and compare three approaches for volume holographic writing /copying in photorefractive media. These include the parallel, increme ntal, and sequential approaches. We show that the three approaches' ac hievable grating modulations and total writing/copying times are ident ical. We then go on to discuss schemes within each approach by which t he copying of one volume holographic memory into a secondary volume ho lographic memory can be optimized. These include all optical, quasi- a ll optical, and opto-electronic schemes. In this analysis, realistic m aterial and device limitations are considered. Our calculations indica te that all optical copying in the parallel approach is the worst opti on, but opto-electronic copying in the sequential approach is the best option.