Patent ID: 7567734

Claim:
An optical sensor for sensing information relating to an analyte liquid or gas, comprising: a planar substrate having a refractive index n c ; a ridge waveguide having at least a region thereof unclad and having a refractive index n r wherein said ridge waveguide is formed upon and supported by substrate, and wherein the substrate serves as cladding layer for the ridge waveguide at a location where the ridge waveguide contacts the substrate; and, a Bragg grating having at least two resonance modes for providing information relating to both temperature and refractive index of the surrounding analyte liquid or gas, wherein a first resonance mode has a different response to the analyte when compared to a second resonance mode, while both modes have a same reaction to temperature, wherein said Bragg grating is formed within the unclad region of ridge waveguide, wherein n c. <n r .