Ridge waveguide optical sensor incorporating a Bragg grating
US7567734B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 8, 2008 |
| Grant date | Jul 28, 2009 |
| Priority date | — |
| Expiry date | Aug 8, 2028 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B2006/12107
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An optical sensor for sensing information relating to an analyte liquid or gas, has a a planar substrate having a refractive index nc. The planar substrate supports a ridge waveguide having an unclad top portion having a refractive index nr. The substrate serves as cladding layer for the ridge waveguide at a location where the ridge waveguide contacts the substrate. A Bragg grating inscribed in the ridge waveguide has two modes for providing information relating to both temperature and refractive index of the surrounding analyte liquid or gas. A cladding mode has a different response to the analyte when compared to a Bragg resonance response. Both modes have a same reaction to temperature, wherein said Bragg grating is formed within the unclad region of ridge waveguide, wherein nc.<nr. Advantageously multiple parameters can be sensed using only a single Bragg grating.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.