Study of PQ/PMMA photopolymer. Part 2: experimental results

In Part 1 of this paper an extended 1D nonlocal photo-polymerization driven diffusion (NPDD) model was developed, giving the temporal and spatial variations of each chemical component concentration within a phenanthrenequinone-doped poly(methyl methacrylate) (PQ/PMMA) material layer. Simulations to study the predicted normalized transmission, the nonlocal effect, and the diffusion of ground and excited states of PQ are presented. In this paper, the validity of the proposed model is examined by applying it to fit experimental data for PQ/PMMA layers containing three different initial PQ concentrations; i.e., 1, 2, and 3 mol. %. The effect of different exposure intensities is also examined. Material parameter values are estimated by numerically fitting experimental normalized transmission curves and refractive index modulation growth curves using the proposed theoretical model.