US Patent 11960216 Invariable magnification multilevel optical device with telecentric converter

A pre-alignment system includes a common object lens group configured to collect diffracted beams from a patterning device, wherein the common object lens group is further configured to produce telecentricity in an object space of the pre-alignment system. The pre-alignment system also includes a multipath sensory array having at least one image lens system, wherein the at least one image lens system includes a telecentric converter lens configured to produce telecentricity in an image space of the pre-alignment system.