Optical sensor employing a refractive index engineered metal oxide material

Abstract

An optical sensor device includes a multilayer hollow waveguide device having a hollow waveguide tube layer, an intermediate layer provided inside the hollow waveguide tube layer, and a metal oxide coating layer inside the intermediate layer.

What is claimed is: 
     
         1 . An optical sensor device, comprising:
 a multilayer hollow waveguide device having:   a hollow waveguide tube layer;   an intermediate layer provided inside the hollow waveguide tube layer; and   a metal oxide coating layer inside the intermediate layer.   
     
     
         2 . The optical sensor device according to  claim 1 , wherein the intermediate layer is a reflective coating layer. 
     
     
         3 . The optical sensor device according to  claim 2 , wherein the reflective coating layer is provided directly on an inner surface of the hollow waveguide tube layer. 
     
     
         4 . The optical sensor device according to  claim 2 , wherein the metal oxide coating layer is provided directly on an inner surface of the reflective coating layer. 
     
     
         5 . The optical sensor device according to  claim 2 , wherein the reflective coating layer is a metal coating layer. 
     
     
         6 . The optical sensor device according to  claim 5 , wherein the reflective coating layer includes silver. 
     
     
         7 . The optical sensor device according to  claim 5 , wherein the reflective coating layer includes gold. 
     
     
         8 . The optical sensor device according to  claim 1 , wherein the hollow waveguide tube layer is made of silica. 
     
     
         9 . The optical sensor device according to  claim 1 , wherein the hollow waveguide tube layer is made of plastic. 
     
     
         10 . The optical sensor device according to  claim 1 , wherein the hollow waveguide tube layer is made of metal. 
     
     
         11 . The optical sensor device according to  claim 10 , wherein the hollow waveguide tube layer is made of Nickel. 
     
     
         12 . The optical sensor device according to  claim 1 , wherein the hollow waveguide tube layer has a first refractive index, wherein the intermediate layer is a guiding layer having a second refractive index that is greater than the first refractive index, and the metal oxide coating layer is structured to have a third refractive index, the third refractive index being less than the second refractive index. 
     
     
         13 . The optical sensor device according to  claim 12 , wherein the guiding layer comprises glass. 
     
     
         14 . The optical sensor device according to  claim 12 , wherein the guiding layer comprises a dielectric material. 
     
     
         15 . The optical sensor device according to  claim 14 , wherein the dielectric material comprises Al 2 O 3 . 
     
     
         16 . The optical sensor device according to  claim 12 , wherein the dielectric material comprises ZrO 2 . 
     
     
         17 . The optical sensor device according to  claim 1 , wherein the metal oxide coating layer has an engineered refractive index and a porosity of 10 nm-50 nm. 
     
     
         18 . The optical sensor device according to  claim 17 , the engineered refractive index is less than a refractive index of silica. 
     
     
         19 . The optical sensor device according to  claim 18 , wherein the hollow waveguide tube layer comprises silica. 
     
     
         20 . The optical sensor device according to  claim 2 , further comprising a protective dielectric coating provided on either or both sides of reflective coating layer. 
     
     
         21 . The optical sensor device according to  claim 12 , wherein the metal oxide coating layer a nanostructure material.