Patent ID: RE41906

Claim:
A two-dimensional beam deflector for a thickness measuring device for measuring the thickness of films on a sample with a plurality of different optical systems each performing a different measurement technique, the beam deflector comprising: two-dimensional translation means for translating said beam deflector along a first scanning axis and along a second scanning axis perpendicular to said first scanning axis; first deflection means for receiving a plurality of parallel input beams along parallel input axes, said input axes being close to each other and parallel to said first scanning axis, and for deflecting said input beams along a plurality of parallel second axes, said second axes being close to each other and parallel to said second scanning axis; second deflection means for receiving a plurality of parallel output beams along parallel third axes, said third axes being close to each other and parallel to said second axes, and for deflecting said output beams along a plurality of parallel fourth axes, said fourth axes being close to each other and parallel to said first scanning axis; and a plurality of optical assemblies, one per input beam, wherein each optical assembly provides its input beam towards said sample, receives its output beam from said sample, processes its input and output beams in accordance with its measurement technique, and provides its output beams along said parallel third axes.