Sughrue Mion, PLLC
Catadioptric reduction lens
A catadioptric projection lens for imaging a pattern arranged in an object plane onto an image plane, preferably while creating a real intermediate image, including a catadioptric first lens section having a concave mirror and a physical beamsplitter having a beamsplitting surface, as well as a second lens section that is preferably refractive and follows the beamsplitter, between its object plane and image plane. Positive refractive power is arranged in an optical near-field of the object plane, which is arranged at a working distance from the first optical surface of the projection lens. The beamsplitter lies in the vicinity of low marginal-ray heights, which allows configuring projection lenses that are fully corrected for longitudinal chromatic aberration, while employing small quantities of materials, particularly those materials needed for fabricating their beamsplitters.
Carl Zeiss SMT AG
G G G G
G03F G02B G03F G02B
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David R. Aurelian Alexander Wilhelm Helmut
Shafer Dodoc Epple Ulrich Beierl