Interferometer with dynamic beam steering element

Abstract

An interferometry system includes: i) a first polarizing beam splitter which during operation separates an input beam into a measurement beam and a reference beam; ii) a beam steering element positioned to direct the measurement beam, and not the reference beam, the measurement beam contacting the beam steering element; iii) an interferometer positioned to receive at least a portion of the measurement beam and direct it to a measurement object, which reflects it to define a return measurement beam, and wherein the interferometer is further positioned to receive at least a portion of the reference beam and direct it to a reference object, which reflects it to define a return reference beam; and (iv) an electronic control circuit coupled to the beam steering element. During operation the control circuit adjusts the orientation of the beam steering element in response to changes in the angular orientation of the measurement object. The beam steering element is further positioned to direct the return reference beam, and not the return measurement beam, the return reference beam contacting the beam steering element. The first polarizing beam splitter recombines the return reference beam and the return measurement beam to form an output beam.

Dependencies are inferred from the claim text.