Abstract

The Polaroid photopolymer holographic material designated as DMP-128 is a phase-only recording medium that offers the high efficiency of dichromated gelatin, yet can be stored in ordinary room conditions after a simple four-step developing process. Light polymerizes a vinyl monomer in the film, producing a modulation of the film’s index of refraction. The film is activated by placing it in air of 51% relative humidity for 3 min. Developing consists of a white-light flood, developing bath, rinse, and dry. Simple plane wave diffraction gratings have been made that are 70% efficient. DMP-128 has been used to make a matched spatial filter. The input scene was an 18-cycle spoked-wheel pattern transparency illuminated in He-Ne light. The incidence angle of the reference beam was 21°. The object/reference intensity ratio was 3:1; total exposure was in excess of 5 mJ/square centimeter. After developing, the filter plate was replaced in its original position and addressed with the object beam. 2.4% of the incident energy was diffracted into the correlation. The peak signal-to-noise (scattered light) ratio was 26.4 (14.2 dB), and the correlation was invariant to translations of the input scene.

© 1986 Optical Society of America