Multiple imaging with thin phase filters: A signal processing approach

Starting from its behavior as an optical processing system some general characteristics of a multiple imaging system are derived. A unique expression for the coherent impulse response cannot be derived because of the allowed arbitrary phase distribution in the output plane and the variation that is permitted in the relative intensities of the multiple images. For a multiple imaging system based on amplitude division, several types of phase gratings are considered. These gratings, two of which were investigated experimentally, result in high-efficiency systems with a wide range of multiplication factors. Finally, some new applications are proposed.