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:
Jun. 02, 2009
Filed:
Jul. 08, 2004
Ernst-dieter Knohl, Koenigsbronn, DE;
Andreas Frommeyer, Aalen, DE;
Hermann Schubert, Thurmansbang, DE;
Ernst-Dieter Knohl, Koenigsbronn, DE;
Andreas Frommeyer, Aalen, DE;
Hermann Schubert, Thurmansbang, DE;
Carl Zeiss SMT AG, Oberkochen, DE;
Abstract
In the case of a method of producing aspherical optical surfaces of optical elements (), in particular for use in microlithography for producing semiconductor elements, the optical element () is ground for example in the form of a meniscus. In a first method step, the optical element () is introduced into a basic form (), which has a spherical form bed and is being held at a distance over the form bed (). After that, an intermediate medium () is introduced in the basic form () between the optical element () and the form bed () and, subsequently the optical element () being removed together with the intermediate medium () from the basic form. Then, the spherical form bed () of the basic form () or a second basic form is transformed into an aspherical form bed (') computationally determined in advance. The optical element () is then re-introduced with the intermediate medium () into the basic form () or the second basic form, the intermediate medium () being sucked against the form bed (′) by applying a vacuum. Subsequently, the optical element () deformed by the vacuum applied is spherically machined on a surface (). Finally, after removing the vacuum, the surface (′) assumes the form of an aspherical surface.