| Photopolymer materials have been becoming a hot spot of research on ultra-high density holographic recording material in recent years because of its many attractive features, such as high diffraction efficiency, high sensitivity, high data transfer rates, parallel processing characters, easy preparation and low cost. However, there were shortcomings of common photopolymer materials such as shrinkage induced by the exposure, and then the shinkage affects the quality of the reading in holographic storage. In this thesis, the hydrophilic Mg(OH)2 nanoparticles were dispersed in acrylamide-based photopolymer. And we studied further on the preparation, holographic storage principle and characteristics of photopolymer. The mainly contents of this thesis were as follows:1. Mg(OH)2 nanoparticles, which have the advantages of small size, good dispersion and hydrophilicity were fabricated, and the photopolymer of acrylimide/polyvinyl alcohol blended with hydrophilic Mg(OH)2-nanoparticles, were also fabricated.2. By evaluating the diffusion coefficient D of nanoparticle/polymer composite hologram and using square-wave particle distribution function, it was proved that the counter diffusion exists in the forming process of the grating of nanoparticles and monomer within the samples.3. The holographic properties of the materials under different exposure conditions were studied. An optimum exposure intensity was found after analyzing the parameters of holographic properties.4. The photopolymer samples doped with different densities of Mg(OH)2-nanoparticles were prepared. Under the optimum exposure scheme, through analyzing the curve of transmittance changing with exposure time, the homogeneity of such photopolymer film was demonstrated.5. The curves of diffraction efficiency, refractive index modulation, exposure sensitivity and other static parameters changing with the densities of Mg(OH)2-nanoparticles and exposure time of the samples blended with Mg(OH)2-nanoparticles of different density were tested. Finally, an optimum plan of Mg(OH)2-nanoparticles density, which allows all holographic properties to attain the ideal value, was worked out.6. The Bragg-mismatch and shrinkage ratio of the optimum concentration of Mg(OH)2-nanoparticles were analyzed. Combining experimental results and theories, we draw the conclusion that adding those nanoparticles can increase the dimensional stability of the samples during the exposure process.7. Two dimensional analog images and digital data pages modulated by the SLM(Spatial Light Modulator) were stored in the the optimum concentration of Mg(OH)2-nanoparticles, and the reconstructed images or data pages have good fidelity.
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