Quantitative study of the gray-scale fidelity of volume holographic images

The reconstruction fidelity of gray-scale holographic images is analyzed quantitatively and assessed by use of proposed quantities, especially the correlation coefficient between the original and the retrieved images. The physical factors affecting the fidelity of photorefractive holograms are investigated experimentally, leading to results that are useful for the determination of the recording-beam ratio and the exposure dosage for high-fidelity retrieval. Investigation of the effects of noise on the fidelity of multiplexed holograms suggests that, if multiple-gray-scale data pages are multiplexed in a given volume, the total bit capacity may be competitive with that realized by means of storing binary pages.