SELF CALIBRATION FOR MIRROR POSITIONING IN OPTICAL MEMS INTERFEROMETERS

Abstract:

A Micro-Electro-Mechanical System (MEMS) interferometer provides for self-calibration of mirror positioning of a moveable mirror. The moveable mirror is coupled to a MEMS actuator having a variable capacitance. The MEMS interferometer includes a capacitive sensing circuit for determining the capacitance of the MEMS actuator at two or more known positions of the moveable mirror and a calibration module for using the actuator capacitances at the known positions to compensate for any drift in the capacitive sensing circuit.