Infrared neutral-density filter having copper alloy film
US5726797A · kind A · utility
4Cited by
4References
13Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jul 25, 1995 |
| Grant date | Mar 10, 1998 |
| Priority date | — |
| Expiry date | Jul 25, 2015 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/31678
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A neutral-density optical filter has a dielectric substrate and a film costing essentially of copper and nickel. The film is preferably formed of Constantan, which is 55% copper and 45% nickel. The filter achieves a high optical density with a low spectral variation.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.