Photopolymers for use as Holographic Media

In this chapter we briefly review some of the developments which have been made in the area of photopolymer material development for applications such as holography. We also examine some of the extensions which have been made to the theoretical models of the processes which occur during free radical photo-polymerisation, namely the Non-local Photo-polymerisation Driven Diffusion (NPDD) model. An understanding of these photochemical and photo-physical processes is of extreme importance when attempting to improve a photopolymer material’s performance for a given application. We will explore the most recent developments made and illustrate some of the useful trends, which this NPDD model predicts and then analyze their implications on photopolymer improvement. Among the effects examined are; the temporal and spatial primary radical generation (the driving force of photo-polymerisation), multiple termination mechanisms, non-local polymer chain growth, the effects of oxygen inhibition, mass transport effects (diffusion), dark reactions (post exposure effects) and chain transfer, to name a few