Waveguide-type optical interferometer
US8150219B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 27, 2007 |
| Grant date | Apr 3, 2012 |
| Priority date | — |
| Expiry date | Jan 22, 2029 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B2006/12159
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
In an optical interferometer, polarization dependence attributable to the optical path difference has conventionally been eliminated by inserting a half-wave plate at the center of the interferometer. However, light induced by polarization coupling produced in directional couplers used in the optical interferometer causes interference having different interference conditions from those of the normal light. Polarization rotators that effect any one of 90° rotation and −90° rotation of all states of polarization of incoming light are inserted in the optical interferometer, and thereby the interference conditions of light induced by polarization coupling are made the same as those of the normal light. Each of the polarization rotators is implemented by using two half-wave plates and by varying an angle of combination of these half-wave plates. Alternatively, each of the polarization rotators is implemented through a combination of one half-wave plate and a waveguide having birefringence properties.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.