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Holographic Recording (holographic + recording)

Distribution by Scientific Domains
Polymers and Materials Science100%

Selected Abstracts

Cover Picture: TiO2 Nanoparticle,Photopolymer Composites for Volume Holographic Recording (Adv. Funct.

ADVANCED FUNCTIONAL MATERIALS, Issue 10 2005
Mater.
Abstract TiO2 nanoparticle,photopolymer composites have been employed for volume holographic recording, as reported by Sánchez and co-workers on p.,1623. Photoinduced segregation of the high refractive index, grafted nanoparticles between polymer-rich areas leads to improved refractive-index modulation amplitudes with respect to the base material without nanoparticles. The cover schematically shows a holographic grating registered in this nanocomposite material. These nanocomposite materials should enable the production of holographic optical elements to efficiently control light with angle and wavelength selectivity. This could be used, for example, in liquid-crystal display technology. A new and efficient photopolymer for the recording of volume holograms is presented. The material comprises a mixture of UV-sensitive acrylates and grafted titanium dioxide nanoparticles with an average size of 4,nm. We report the formation of holographic gratings with refractive-index modulation amplitudes of up to 15.5,×,10,3,an improvement of more than a factor of four over the base material without nanoparticles,while maintaining a low level of scattering and a high transparency in the visible-wavelength range. The influence of the composition of the acrylate system on the final properties of the holographic material is also investigated and discussed. The presence of multifunctional monomers favors the compositional segregation of the different components, while the addition of monofunctional acrylate, highly compatible with the grafting of the nanoparticles, favors the dilution of these nanoparticles. [source]

Dendritic polyisophthalate endcapped with naphthyl groups for holographic recording,

POLYMERS FOR ADVANCED TECHNOLOGIES, Issue 9 2004
Huiguang Kou
Abstract A novel dendritic polyisophthalate with 12 naphthyl groups at the chain ends was synthesized from 5-hydroxyisophthalic acid as an AB2 monomer, 1,3,5-benzenetricarbonyl trichloride as an ,initiator core' molecule, and , -naphthol as an endcapping reagent, via a stepwise growth process. An average molecular weight of 2860,g,mol,1, and a refractive index of 1.618 at 650,nm were obtained by gel permeation chromatography and ellipsometry, respectively. A photopolymerizable recording dry film incorporating this dendrimer as a polymeric binder was used for holographic recording. Diffraction gratings with diffraction efficiency exceeding 80%, together with a modulation index of 10,2 were obtained. Copyright © 2004 John Wiley & Sons, Ltd. [source]