Performance improvement of high thickness photopolymers for holographic data storage applications

摘要

We use 4,4' azo-bis-(4-cyanopentanoic acid) as chain transfer agent in a photopolymer with triethanolamine/yellowish eosin as initiator system. It is possible to work in a particular conditions to get a chain transfer effect minimizing the decomposition of 4,4' azo-bis-(4-cyanopentanoic acid) by the sensitized dye. The improved photopolymer has a low scattering due to the low molecular weight of the generated polymer chains. This is related to the chain transfer effect in the size of the polymer chains. It is important to establish the optimum concentration of chain transfer agent to avoid decreasing the maximum diffraction efficiency due to a low molecular weight of the polymer chains.