Optical devices comprising series of birefringent waveplates
US7242517B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 31, 2002 |
| Grant date | Jul 10, 2007 |
| Priority date | — |
| Expiry date | Oct 28, 2022 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02F1/093
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
Bidirectional isolating devices including non-reciprocal rotators (i.e. Faraday rotators) and wavelength selective reciprocal polarization rotators are disclosed. Each wavelength selective rotator behaves like a half-wave retarder in a first frequency range and behaves like a full-wave retarder in a second frequency range, according to a substantially periodic transfer function. The rotation has a predetermined number of birefringent elements (e.g. waveplates), the thickness and the orientation of which are chosen so as to obtain a transition between the half-wave retarder behavior and the full-wave retarder behavior in a frequency range lower than or equal to 40% of the period of the transfer function. In order to satisfy such a requirement, a relatively high number of birefringent elements is required, i.e. at least the five birefringent elements. Advantageously, the isolating device may comply with any allocation scheme for the opposite propagating signals.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.