Method and apparatus for modulating signal strength within optical systems
US6385368B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 19, 1999 |
| Grant date | May 7, 2002 |
| Priority date | — |
| Expiry date | Feb 19, 2019 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02F2203/03
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
Embodiments of the invention include an optical system apparatus and method for modulating the strength of a grating such as a long period grating (LPG) within optical systems and devices by varying the light transmission and loss characteristics of the cladding mode, rather than varying the effective refractive index of the fiber layers. According to embodiments of the invention, the use of a light-scattering or light absorptive material in the cladding of the optical fiber or other optical energy transmission medium causes the cladding to switch between a first state that effectively allows coherent coupling of cladding modes and a second state that effectively prevents coherent coupling of cladding modes. The light-scattering materials include electro-optic materials that cause the cladding to switch between the first and second states based on the presence (or absence) of an electric field, magneto-optic materials that cause the cladding to switch between the first and second states based on the presence (or absence) of a magnetic field, and materials capable of phase transitions that cause the cladding to switch between the first and second states based on temperature. The lig…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.