Patent ID: 6437867
Filing Date: 2002-08-20
Classification: A61B,G01B,G01N

Abstract:
A system for performing selected optical measurements on a sample comprising:a. a broad band light source, b. means for splitting light from said light source into a signal beam and a reference beam, c. a reference mirror disposed along the path of the reference beam, d. means for bringing the signal beam to focus on said sample, e. a diffraction grating for receiving reflections from the sample and from the reference mirror, the reflections from the sample and the reference mirror being incident on the diffraction grating such that a diffraction order from each of said reflections propagate along a normal to said diffraction grating, the diffraction order from reflections from the sample being the same number as the diffraction order from reflections from the reference mirror, the diffraction order from one of said reflections being a positive order and the diffraction order from the other one of said reflections being a negative order, f. a detector, g. means for collecting the diffracted orders from said diffraction grating propagating along said normal and bringing said diffracted orders to focus on said detector, said detector producing an output of said diffracted orders received, and h. means for processing said output from said detector.