Patent ID: 7612931

Claim:
An optical system comprising: a MEMS structure movable between a first position in which light is redirected from a first input port to an output port and a second position in which light is redirected from a second input port to the output port, the first input port spatially separated from the second input port; a MEMS actuator for moving the MEMS structure between the first and second positions, and for dithering an orientation of the MEMS structure about the first and second positions; a detector optically coupled to the output port for monitoring an intensity of the dithered light and for providing a feedback signal in dependence upon the monitored intensity; and a controller for receiving the feedback signal from the detector, for determining a control loop gain used in active alignment of the MEMS structure, for applying a first normalization function to the control loop gain, and for applying a second normalization function to a dither magnitude, wherein the first normalization function is selected in dependence on the second normalization function, wherein the first input port transmits light from a first laser in a laser array, and the second input port transmits light from a second laser in the laser array, wherein the output port transmits light into an input waveguide of an optical modulator, and wherein the feedback signal is shared between four separate control loops, a first control loop for actively aligning the MEMS structure in a first dimension, a second control loop for actively aligning the MEMS structure in a second other dimension, a third control loop for controlling the bias of the optical modulator, and a fourth control loop for controlling a driver voltage of the optical modulator, the control loop gain corresponding to a gain provided in the first control loop.