Patent ID: 7292341

Claim:
An optical system for use in measurements in a sample, the system comprising: (a) a light source operable to produce an incident light beam propagating in a certain direction towards the sample through an illumination channel; (b) a detector unit for collecting light coming from the sample through a detection channel, and generating data indicative of the collected light; and (c) a light directing assembly operable to direct the incident beam onto a certain location on the sample's plane with a plurality of incident angles, and to direct light returned from the illuminated location to the detector unit, the light directing assembly comprising a plurality of beam deflector elements, at least one of the deflector elements being movable, a position of said at least one movable deflector element defining a selected one of the incident angles, wherein the light directing assembly defines an additional illumination/detection channel for directing the incident beam onto the sample along an axis perpendicular to the sample's plane and directing a reflection of the perpendicular incident beam to the detector.