Abstract
We discuss a digital holographic memory that uses highly sensitive strontium barium niobate as a recording medium. Despite equalizing the diffraction efficiencies of recorded holograms by using schedule recording, we observed degradation of the reconstructed image near the beginning of multiplexing. Concluding that the degradation was caused by medium saturation, we tried to reduce it by using a random phase shifter and modulation code. Random phase shifters were not effective to reduce the medium saturation while 2:4 modulation code could reduce it. As a result we improved the signal-to-noise ratios of the reconstructed images and hence the bit error rates. In 50-times multiplexing, we obtained bit error rates of less than 10^<-3> which can be eliminated by conventional error correction.
