Patent ID: 7189961

Claim:
A scanning beam device comprising: a drive assembly; a scanning element coupled to the drive assembly so that the scanning element moves and light emitted from the scanning element scans laterally; a housing that surrounds the drive assembly and the scanning element; one or more detectors positioned within the housing and spaced from the scanning element; and an optical assembly disposed substantially at a distal end of the housing assembly, the optical assembly adapted to direct the light from the scanning element to a target area distal of the optical assembly and adapted to direct at least a portion of light reflected from the target area to the one or more detectors; wherein the scanning element delivers a linearly polarized light to the target area so that the light reflected from the target area comprises multiple polarization states depending on the nature of the target area, wherein at least one element of the optical assembly comprises a birefringent material that directs light reflected from the target area that is of a first polarization to the scanning element and light reflected from the target area that is of a second polarization to the one or more detectors.