An optical reduction system for use in the photolithographic manufacture of semiconductor devices having one or more quarter-wave plates operating near the long conjugate end. A quarter-wave plate after the reticle provides linearly polarized light at or near the beamsplitter. A quarter-wave plate before the reticle provides circularly polarized or generally unpolarized light at or near the reticle. Additional quarter-wave plates are used to further reduce transmission loss and asymmetries from feature orientation. The optical reduction system provides a relatively high numerical aperture of 0.7 capable of patterning features smaller than 0.25 microns over a 26 mm5 mm field. The optical reduction system is thereby well adapted to a step and scan microlithographic exposure tool as used in semiconductor manufacturing. Several other embodiments combine elements of different refracting power to widen the spectral bandwidth which can be achieved.

 
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