Patent ID: 7872735
Filing Date: 2011-01-18
Classification: G01D

Abstract:
1. A method of calibrating a micro-electro-mechanical (MEMS) device having a MEMS mirror for reflecting light, and a MEMS actuator for tilting the MEMS mirror in response to an applied voltage having a voltage value, the method comprising: providing m emitting waveguides for emitting light, wherein m is an integer positive number; providing n receiving waveguides for receiving light, wherein n is an integer positive number, and wherein each receiving waveguide has two first and second ends, and wherein the first end of each receiving waveguide is available for receiving light, and wherein the second end of each receiving waveguide is optically coupled to a photodetector for measuring the power of light impinging thereon; providing a coupler for coupling a light emitted by any one of the m emitting waveguides to the MEMS mirror, and for coupling the light reflected from the MEMS mirror into a particular of the n receiving waveguides in dependence upon an angle of tilt of the MEMS mirror; applying up to m*n voltage values to the MEMS actuator, wherein m*n>1, and, for each voltage value applied, measuring the power of light emitted from one of m emitting waveguides and coupled into one of n receiving waveguides, wherein said powers of light are measured using the respective photodetectors; determining a relationship between an angle of tilt of the MEMS mirror and a voltage applied to the MEMS actuator, from the applied voltage values and the measured values of power of light.