Abstract

Holographic and surface-relief gratings are of wide interest due to their many applications in integrated optics, acoustooptics, holography, optical data and image processing, and spectral analysis. A significant number of recent applications, including optical interconnects, acoustooptical signal processing, multicolor display, wavelength multiplexing and demultiplexing, optical computing, associate storage, coherent beam addition, and beam coding, involve diffractive optical elements containing two or more multiplexed gratings. Recently, a rigorous coupled-wave analysis of multiplexed holographic gratings has been developed by the author. The analysis is applicable to multiplexed holographic gratings with arbitrary periodicity, slant angle, modulation, thickness, and incident plane wave with arbitrary polarization, angle of incidence, and light wavelength. In this work the angular selectivity characteristics of two multiplexed gratings are investigated using the coupled-wave analysis. In this study, both relatively thin (10-µm) photographic emulsion-type gratings and relatively thick (2-mm) photorefractive-type gratings are considered. The crosstalk and the minimum angle separation between the two gratings are determined for these typical gratings with low, intermediate, and high diffraction efficiency. In addition, the effect of the angle of incidence on the minimal angular separation between the two gratings is investigated.

© 1988 Optical Society of America