Planer waveguide and method of formation
US6807349B2 · kind B2 · utility
Inventor
Key dates
| Filing date | Sep 4, 2001 |
| Grant date | Oct 19, 2004 |
| Priority date | — |
| Expiry date | Aug 3, 2022 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02F1/225
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
The present invention provides a method of forming a planar optical waveguide comprising the steps of forming a silica-based waveguide at a first temperature which is below a melting temperature of material from which the waveguide is formed; and annealing a region of the waveguide at a second temperature which is greater than the formation temperature and less than a melting temperature of material from which the waveguide is formed, so as to alter an effective refractive index of the region. In one embodiment the step of annealing is preceded by the step of forming a thin film heater over the region of the waveguide, the heater being capable of heating the region to the second temperature. The first temperature is preferably low (below 400° C.) to maximize the range of annealing temperatures.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.