Imaging optical system configured with through the lens optics for producing control information
US7612892B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 5, 2006 |
| Grant date | Nov 3, 2009 |
| Priority date | — |
| Expiry date | Jan 13, 2027 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B27/40
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A new and useful imaging concept is provided that is designed to improve the manner in which control information for an imaging optical system such as a lithographic imaging optical system can be generated. An imaging optical system comprises imaging optics defining a primary optical path along which a primary image is imaged, and a measurement optical path is established and includes at least part of the primary optical path. The imaging optical system is configured to obtain information from the measurement optical path for use in providing control information for the imaging optical system. Such a system is particularly useful for measuring the topography of a large region of the surface under investigation, like the entire instantaneous field of a wafer, instead being limited to a small patch or set of patches.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.