Optical modulators and a method for modulating light
US6904186B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 12, 2002 |
| Grant date | Jun 7, 2005 |
| Priority date | — |
| Expiry date | Feb 28, 2023 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02F2203/21
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An optical modulator modulates light propagating in a three-dimensional optical waveguide 5 by applying a voltage on the waveguide. The modulator has a three dimensional optical waveguide 5 having at least a pair of branched portions 5b, 5c and a recombining portion 5f of the branched portions 5c, 5d and radiating light of off-mode, and a slab optical waveguide 4 guiding the light of off-mode. The modulator also has modulating electrodes 7A, 7B, 7C for applying a signal voltage and a direct current bias on the waveguide 5 to modulate light propagating in the waveguide 5. The modulator further has a photo detector 13 for detecting light radiated from the slab optical waveguide 4, and a controlling unit 15 for varying the direct current bias based on an output from the photo detector 13 so as to control the operational point of the modulator. According to the modulator, the operational point may be controlled with improved efficiency and stability.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.