GaAs asymmetric Fabry-Perot vertical cavity modulators are useful in a wide variety of applications. Such modulators have been demonstrated in large format arrays. The majority of vertical cavity devices have employed amplitude modulation to produce optical switching. Additional uses for the pixels include detection, phase modulation, directional modulation, and light-emitting capability. When arrays of these devices are integrated with electronic circuits-most significantly silicon CMOS VLSI-at the pixel level, large, complex optical spatial light modulators, detectors, transceivers, computation devices, and emitters can be created for a wide variety of applications. These applications range from target recognition to SAR radar processing, to optical data routing, to optical interconnect systems, to optical memory access.