Broadband silicon nitride polarization beam splitter
US9366818B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 6, 2015 |
| Grant date | Jun 14, 2016 |
| Priority date | — |
| Expiry date | Nov 6, 2035 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B2006/12164
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A compact polarization beam splitter is formed by cascading two stages of directional couplers each containing two waveguides laid in parallel with a coupling gap. Each waveguide is made by silicon nitride material having a minimum length configured to be comparable with a coupling length for a TE polarization mode being set as twice of a coupling length for a TM polarization mode. A first-stage direction coupler is optimized by making the coupling gap smaller/greater than a nominal value to maximize TE/TM extinction ratio at least for a shorter/longer wavelength window of a designated wavelength band and each of two second-stage directional couplers is optimized by making the coupling gap greater/smaller than the nominal value to maximize TE/TM extinction ratio at least for a complementary longer/shorter wavelength window of the same designated wavelength band.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.