Thin-film interference filter with quarter-wavelength unit sub-layers arranged in a generalized pattern
US6611378B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 20, 2001 |
| Grant date | Aug 26, 2003 |
| Priority date | — |
| Expiry date | Jan 21, 2022 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S359/90
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
Thin-film interference filters are constructed with a generalized pattern of layers differing in both thickness and refractive index to produce spectral responses appropriate for adjusting optical power among a plurality of different wavelength channels. Each of the layers is composed of unit sub-layers having thicknesses equal to a quarter-wavelength thickness of a monitoring beam. Interference fluctuations of the monitoring beam associated with the deposition of the unit sub-layers enable a gain-flattening filter to achieve greater manufacturing accuracy by exploiting self-correcting effects of “turning point monitoring” techniques.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.