Abstract

Computer-generated gratings which produce a number of equal intensity diffraction orders have been of interest recently for various applications. One application is the distribution of light energy on 2-D arrays of optical logic devices in an optical computer. Different schemes to achieve high uniformity and high efficiency have been investigated. Our approach is an extension of Dammann’s theory of binary diffraction gratings.¹ An increase in afficiency can be obtained by using more than two phase levels. Gratings were fabricated using quartz glass substrates and reactive ion etching techniques. We present a theory of multilevel phase gratings as array generators and show experimental results. The performance of binary and multilevel phase gratings is compared.

© 1988 Optical Society of America