Dark diffusion transient in a blue-green sensitized holographic photopolymer was investigated based on a previously published theoretical model of monomer diffusion. Diffusion time constant of monomers was obtained by fitting the experimental data to the theoretical model. According to the results of diffusion time constant, experiments were designed and conducted to investigate the evolution of grating efficiency with non-continuous holographic exposure. The experimental result indicated that the saturated diffraction efficiency of a non-continuously exposed grating is about 1.25 times of that of continuously exposed one under the same recording condition.© (2007) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.