Abstract

Hybrid-optical (optical-electronic-digital) systems have the potential to gain an important role in signal processing due to their compactness, versatility, and adaptability. Three major components often incorporated into such hybrid architectures are laser diodes, acoustooptic cells, and time-integrating solid state array detectors. Recently, high-power single-mode laser diode systems have become available enabling the useful operation of a certain class of hybrid-optical interferometric processors. In this class of processors, the diffracted and undifffracted orders of an acoustooptic cell are interfered. Due to the relative Doppler frequency shift between the orders, the interference fringes are modulated at the Doppler frequency. This typically would cause the destruction of fringe visibility when observed with time-integrating detectors such as TV cameras. To retain fringe visibility, optical source modulation is introduced which freezes the fringes to produce a high visibility output. Experimental results are shown for an interferometric hybrid-optical processor which incorporates fringe freezing.

© 1986 Optical Society of America