A THEORETICAL-MODEL FOR NOISE GRATINGS RECORDED IN ACRYLAMIDE PHOTOPOLYMER MATERIALS USED IN REAL-TIME HOLOGRAPHY

Among the different sources of noise in holography, noise gratings hav e been analysed extensively in photographic emulsions owing to the gra nular nature of these recording materials; however, information about photopolymers is quite scarce. The effect of age on transmittance curv es in a photopolymer system, used as holographic recording material, s hows the appearance of noise gratings. We present a theoretical model, which explains the results for transmittance as a function of time in the presence of noise gratings recorded in an acrylamide mixture phot opolymer. Good agreement between theory and experience has been observ ed, and the model can be used to obtain an approximate value for the d iffraction efficiency of noise gratings, as well as to explain the res ults of age in transmittance curves.