Optical phased array beam deflection using lead lanthanum zirconate titanate

Optical phased arrays can provide a versatile means for fast, solid-state, random-access beam steering. This dissertation presents both the theory of phased array beam deflection and the experimental development of a high speed optical phased array based on Lead Lanthanum Zirconate Titanate (PLZT), a fast switching transparent electrooptic ceramic. An optimal strategy for cascading phased array deflectors is developed which allows for high-resolution random-access beam steering with continuous scan angle control but requiring a minimum number of control lines. A phase-staggered Discrete/Offset Bias protocol for controlling the cascaded system is shown to provide the best optical performance. The development, testing, and characterization of PLZT-based phase modulators is described in detail. A set of 16-channel and 32-channel optical phased arrays were designed and fabricated using surface electrodes on PLZT and used to experimentally demonstrate the beam steering performance of both single-stage and two-stage phased array systems. Further device improvements are shown that demonstrate enhanced light throughput of the phased array design using telecentrically aligned lenslet arrays. Sub-microsecond switching rates of the PLZT-based phase modulators are also experimentally verified.