Abstract

The development of free-space optical interconnect systems has created a need for efficient algorithms for the design of multiple beam splitting optical elements commonly referred to as array generators. A technique for the design of continuous phase gratings is presented that is based on the representation of the array generator in terms of complex poles and zeroes. Infinite impulse response filter design theory is then applied to array generator design; an all-pass IIR filter insures that the phase-only constraint is always satisfied. A stochastic optimization algorithm is presented that is based on the specification of complex poles and zeroes. Preliminary results indicate the efficacy of using IIR filter design techniques, but grating performance to date is only moderate. Phase gratings have been designed that generate spot arrays at ~90% diffraction efficiency with 7% uniformity.

© 1991 Optical Society of America