System and method for uniformity correction
US7525641B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 7, 2005 |
| Grant date | Apr 28, 2009 |
| Priority date | — |
| Expiry date | Apr 7, 2027 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F7/70191
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A system and method for uniformity correction is provided. The system includes a plurality of winged correction elements inserted into the illumination field in a defined configuration. Adjacent winged correction elements are overlapped to minimize induced uniformity ripple. Each winged correction element has a first protrusion on a longitudinal edge of the correction element and a second protrusion on the opposite longitudinal edge. The slope of a sloped edge of the first protrusion and the slope of a sloped edge of the second protrusion are tied to the slope of a gradient in the non-uniformity profile of the illumination field. In addition, the angles defined by the flat tip of the correction element and the sloped edge of the first and second protrusions are tied to the angle of a gradient of the illumination field.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.