High-Performance Chirped Electrode Design for Cat's Eye Retro-Reflector Modulators

Modulating retro-reflector (MRR) systems typically use large area surface-normal modulators with large lateral current flow. Frequency response is limited by the resistance capacitance time constant. In cat's eye MRRs, only a small percentage of the modulator area is illuminated at a time. Uniform resistance to each part of the modulator is desired to decrease location dependence of frequency response. A novel "chirped" grid electrode was designed to balance semiconductor sheet resistance and metal line resistance components of the series resistance. Measured rise/fall times across the device showed good uniformity