Unit magnification projection lens system
US5696631A · kind A · utility
13Cited by
2References
9Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Feb 22, 1996 |
| Grant date | Dec 9, 1997 |
| Priority date | — |
| Expiry date | Feb 22, 2016 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B13/26
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A unit magnification lens system suitable for imaging of features in photoresist designed for exposure at a wavelength of 248.4 nm using a krypton fluoride excimer laser. This lens system is characterized by a very long working distance in the object and image spaces to allow incorporation of minors in the imaging path. The optical system is refractive, telecentric, and symmetrical about the central aperture stop.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.