Fiber-optic displacement sensor with 0.02 μm resolution by white-light interferometry

Abstract A system of fiber-optic displacement sensors is described. Interferometric transducers and receivers are linked in various combinations by multimode fibers. Michelson and Fabry-Perot interferometers serve as the transducers. Receivers are of the Michelson type, scanned either mechanically to provide a wide range (20 mm) at low repetition (1/s), or electronically with a CCD photodiode array, offering fast read-out (