Method for making element
US6641985B2 · kind B2 · utility
25Cited by
8References
17Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Oct 27, 1999 |
| Grant date | Nov 4, 2003 |
| Priority date | — |
| Expiry date | Oct 27, 2019 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F7/0005
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A SiO2 thin film is formed on a SiO2 substrate provided with a binary-type diffractive element by a radiofrequency sputtering process so as to cover the fine irregularities formed on the substrate caused by misalignment of masks in the production process. This film planarizes the surface having the fine irregularities and thus prevents a decrease in diffraction efficiency.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.