An application of azo-dye-doped polymer films in optical signal processing using Fourier holograms

摘要

Investigations have been carried out on azo-dye-doped polymer films to determine their suitability for use in information processing by holographic methods. The holographic build-up and erasure times of the azo dye Disperse Red 13 in polymethyl methacrylate, have been measured. These measurements have been taken at different reference-to-signal-beam-intensity ratios to determine the optimum ratio for maximum diffraction of the readout beam by the photoinduced grating. The edge enhancement of various objects, both simple and complex, was demonstrated with this azo-dye-doped polymer film, illustrating the possibility of nonlinear optical filtering using such photoanisotropic materials. The special feature of the described method is the use of the two interacting beams without any additional devices. Furthermore this method allows the edge enhancement of moving objects.