Acoustooptic time-integrating correlators and optoelectronic mixers

Research during the past year has been concentrated on the developement of the InP optoelectronic switch and on the evaluation of this switch as an electronic mixer. This type of mixer appears well suited for use in a time-integrating correlator which employs a heterodyne detector array. In such an array, a small high-quality mixer is crucial. InP optoelectronic switches have been fabricated using interdigitated-finger electrode structures with finger and space lengths varying from 6 micrometers for the most widely spaced device to 1.25 micrometers for the most closely spaced device and active areas of 48 x 48 micrometers. The performance of these devices in both the conventional (switch) mode and the bilinear mode of mixing has been evaluated.