Patent ID: 9568640
Date: 2017-02-14
CPC Classifications: G01V

Claim:
1. An apparatus for estimating a parameter, comprising: a multi-wavelength electromagnetic source configured to emit electromagnetic radiation beams having multiple wavelengths at a fixed angle relative to an interferometer, the multi-wavelength source having a stabilizer configured to lock each beam to one of a plurality of discrete wavelength ranges; the interferometer including a fixed reference reflector and a moveable reflecting surface coupled to a moveable mass, the moveable reflecting surface facing the fixed reference reflector, the mass configured to move in response to the parameter, the multi-wavelength source configured to emit a plurality of beams at the same fixed angle relative to the interferometer, each of the plurality of beams having a different wavelength; a detector configured to detect an interference pattern generated by the interferometer for each beam, the interference pattern resulting from reflections of a beam between the fixed reference reflector and the movable reflecting surface; and a processor configured to combine the interference patterns and estimate the parameter based on the combined interference pattern.