Projection mask as well as a method and apparatus for the embedding thereof and projection printing system
US4390273A · kind A · utility
468Cited by
7References
17Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Feb 17, 1981 |
| Grant date | Jun 28, 1983 |
| Priority date | — |
| Expiry date | Feb 17, 2001 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/24917
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A projection mask and method and apparatus for production thereof comprising a substrate carrying a mask thereon, a cover glass covering the pattern mask and sealed at peripheral edges thereof to the substrate defining a space between the substrate with the mask and the cover glass. A particle-free fluid is provided in this space. A projection printing system projects illumination through such a projection mask into a light sensitive substrate.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.