Patent ID: 6653649
Filing Date: 2003-11-25
Classification: G01B,G02B

Abstract:
An optical measurement and inspection system comprising:an optical illumination system for producing a beam for illuminating a surface under inspection; a detector for measuring light reflected from said surface under inspection; a partially reflective surface positioned between said surface under inspection and said detector and forming a resonator with said surface under inspection, wherein said partially reflective surface is positioned at a tuned optical distance from said surface under inspection in conformity with a predetermined wavelength of said optical illumination system, whereby a sensitivity of said detector to light reflected from said surface under inspection is increased due to multiple reflections within said resonator; and a scanning system for moving said beam and said partially reflective surface with respect to said surface under inspection, wherein said detector detects variations in an optical path between said partially reflective surface and said surface under inspection in response to said moving.