Projection optical unit for imaging an object field into an image field, and projection exposure apparatus comprising such a projection optical unit
US10146033B2 · kind B2 · utility
1Cited by
6References
24Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Dec 8, 2015 |
| Grant date | Dec 4, 2018 |
| Priority date | — |
| Expiry date | Feb 17, 2036 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG21K1/067
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A projection optical unit images an object field in an image field. The projection optical unit includes a plurality of mirrors guides imaging light from the object field to the image field. At least two of the mirrors are arranged directly behind one another in the beam path of the imaging light for grazing incidence with an angle of incidence of the imaging light which is greater than 60°. This results in an imaging optical unit that can exhibit a well-corrected imageable field with, at the same time, a high imaging light throughput.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.