Practical considerations of retroreflector choice in modulating retroreflector systems

Optical modulating retroreflectors (MRRs) were demonstrated before the invention of the laser, but were restricted to short distances and low data rates. Recent advances in optoelectronic devices and free space optics have greatly increased the capabilities of MRR systems. Several modulator technologies have been used in MRR systems and compared elsewhere. In this discussion, practical considerations of the two types of bulk optic retroreflectors used in km-range MRRs were compared: corner cube retroreflectors and cat's eye retroreflectors. Examples of MRR systems using each type are given.