Eosin dye soaked gelatin as a recording medium

Surface relief gratings on eosin dye soaked gelatin films are created on ex posure to polarized cw diode pumped Nd:YAG laser beam at 532 nm without any subsequent processing steps and the progression of the grating inscription is monitored by measuring the growth of the intensity of first order diffr acted beam over time with 633 nm beam of a He-Ne laser. Diffraction efficie ncy of the grating is found to depend on time of exposure, intensities and intensity ratio of the interfering beams, and concentration of the dye in g elatin. A diffraction efficiency up to 30% is observed. The recording is pr edominantly surface relief. The surface modulations of the grating generate d are investigated using an atomic force microscope. (C) 2000 Society of Ph oto-Optical instrumentation Engineers. [S0091-3286(00)00208-7].