We report an electron-probe microanalysis of a hologram recorded in a silica-nanoparticle-dispersed photopolymer film. We used S and Si atoms as label elements to identify formed polymer and nanoparticle species, respectively. It is found that the periodic density distributions of S and Si atoms are out of phase with each other, indicating that those of the formed polymer and nanoparticles are out of phase each other. This result shows decisive evidence of the mutual diffusion of monomer molecules and silica nanoparticles in the film under holographic two-beam interference exposure.

We report on the use of hyperbranched polymers (HBPs) acting as mobile organic nanoparticles doped in methacrylate photopolymers for highly efficient volume holographic recording. Two types of reduced HBPs having the average size of 10nm are synthesized. The diffraction efficiency near 100% in the green (532nm) and substantive polymerization-shrinkage suppression in this photopolymer system are demonstrated. Periodic assembly of HBPs under holographic exposure is also observed.

We describe the diffraction properties of organic nanoparticle-dispersed photopolymers in which hyperbranched polymers (HBPs) act as transporting organic nanoparticles that increase the refractive-index contrast of a hologram. We prepared HBPs by the living radical vinyl polymerization of inimers under ultraviolet-light illumination. Such synthesized HBPs are easy to disperse into monomers without any aggregation, so that samples with good optical quality are available. We investigate the role of HBPs in the recording process for two different types of photopolymers capable of radical polymerization and cationic ring-opening polymerization. We also evaluate the effect of HBP dispersion on recording sensitivities and polymerization shrinkage.

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We describe a new type of nanocomposite photopolymer system in which nanoparticles having a large refractiveindex difference from formed polymers are dispersed in monomers for permanent volume holographic recording. A model for the holographic grating formation based on the mutual diffusion of monomers and nanoparticles is discussed. The diffraction properties of volume holograms recorded in the nanocomposite photopolymer system are described. Experimental evidence of holographic control of nanoparticle-distribution morphology in a photopolymer is also shown.