Projection lens system and apparatus
US6008884A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 27, 1998 |
| Grant date | Dec 28, 1999 |
| Priority date | — |
| Expiry date | Apr 27, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B13/26
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A high-performance dioptric reduction projection lens and projection exposure apparatus and projection exposure method using same. The projection lens includes six lens groups and has a positive negative positive negative positive refractive power arrangement. The third and fifth lens groups have overall positive refractive power and include at least three lens elements having positive refractive power. The fourth lens group has negative refractive power and includes at least three lens elements having negative refractive power. At least one lens element in either the fourth lens group or the fifth lens group includes an aspheric surface. The projection lens preferably satisfies at least one of a number of design conditions.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.