Real-time active alignment demonstration for free-space optical interconnections

A real-time active alignment system is reported for short-distance free-space optical interconnections that compensates for dynamical disturbances. Real-time misalignment compensation is a solution to achieve tight alignment tolerances without compromising the spatial density of the optical channels. A piezoelectric microstage and a proportional-integral-derivative (PID) control scheme was implemented in an experimental system and misalignment error compensation was demonstrated up to 118 Hz.