Zoom system, in particular, a zoom system for an illumination device of a microlithographic projection system
US6900946B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Mar 5, 2004 |
| Grant date | May 31, 2005 |
| Priority date | — |
| Expiry date | Mar 5, 2024 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B13/22
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A zoom system that is particularly suited to use on an illumination device of a microlithographic projection exposure system and is configured in the form of a focal-length-zooming lens. The lenses of the zoom system define an object plane (6) and an image plane (8) that is a Fourier transform of the object plane. Both an intermediate pupillary plane (25) that is conjugate to the image plane and an intermediate field plane (27) that is a Fourier transform of the image plane lie between the object plane (6) and image plane (8). At least one movable lens (31, 32) is arranged in the vicinity of these intermediate image planes (25, 27). The system is characterized by a large expansion of the illuminated area on the image plane for short lengths of travel and light weights of these movable lenses (31, 32).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.