Fish & Richardson P.C.
Projection lens, projection exposure apparatus and projection exposure method
A refractive projection lens for imaging a pattern in an object plane of the projection lens into an image plane of the projection lens via electromagnetic radiation of a mercury vapor lamp includes a multiplicity of lens elements are arranged along an optical axis between the object and image planes. The lens elements image a pattern in the object plane into the image plane with a reducing imaging scale. The lens elements include first lens elements made of a first material with a relatively low Abbe number and a second lens elements made of a second material with a higher Abbe number relative to the first material.
Carl Zeiss SMT GmbH
G G G G G G G
G03F G03F G02B G02B G02B G03F G03F
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Alexander David
Epple Shafer