Patent ID: 7388663

Claim:
A lithographic apparatus, comprising: an illumination system that produces a beam of radiation; a pattern generating device that patterns the beam; a substrate table that supports a substrate, the substrate having alignment marks provided on a surface thereof relative to a plurality of panels having variable or different dimensions, the plurality of panels being supported on the substrate; a frame moveable relative to the substrate; a plurality of projection systems coupled to the frame, wherein the plurality of projection systems are capable of projecting respective portions or copies of the patterned beam onto a target portion of respective ones of the plurality of panels having variable or different dimensions on the substrate; one or more alignment mark detectors coupled to the frame and moveable with respect to the frame, wherein the detectors detect alignment marks by analyzing reflection patterns; and a position sensor associated with each of the one or more alignment mark detectors, wherein the position sensor determines the position of the one or more alignment mark detectors relative to at least one of the frame and the plurality of projection systems.