The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 03, 2007
Filed:
Sep. 01, 2004
Aksel Goehnermeier, Aalen, DE;
Alexandra Pazidis, Aalen, DE;
Birgit Kuerz, Aalen, DE;
Christoph Zaczek, Hebach, DE;
Daniel Kraehmer, Aalen, DE;
Aksel Goehnermeier, Aalen, DE;
Alexandra Pazidis, Aalen, DE;
Birgit Kuerz, Aalen, DE;
Christoph Zaczek, Hebach, DE;
Daniel Kraehmer, Aalen, DE;
Carl Zeiss SMT AG, Oberkochen, DE;
Abstract
An objective, in particular a projection objective for a microlithography projection-exposure installation, with at least one fluoride crystal lens is disclosed. A reduction in the detrimental influence of birefringence is achieved if this lens is a (100)-lens with a lens axis which is approximately perpendicular to the {100} crystallographic planes or to the crystallographic planes equivalent thereto of the fluoride crystal. A further reduction in the detrimental influence of birefringence is obtained by covering an optical element with a compensation coating.