Patent ID: 7502121

Claim:
An apparatus for distance ranging of the surface of materials by means of an optical low coherence Michelson interferometer, comprising a reference and a sample arm, in which a sample arm of the interferometer comprises a single mode fiber-optic guide connected to a probe head where the probe head comprises a beam shaping assembly which directs and focuses a portion of the sample beam towards an interface of the specimen, which reflects a portion of the sample beam back to the interferometer, and a reflective means constituting a base interface which reflects a portion of the sample beam back to the interferometer, where the reflective means is mounted a certain distance from the probe head, where the probe head comprises a beam splitting means, which splits the sample beam into one portion and towards a reflective means and a second portion of the sample beam towards a reflective interface of the specimen; and a reference arm, which comprises a single fiber optic mounted on a stage for polarization control and connected to a collimator, which directs the beam toward s a reflective element, which resides on a delay stage.