Patent ID: 9664852
Date: 2017-05-30
CPC Classifications: G02B,H01P

Claim:
1. A waveguide, comprising: a substrate; a plurality of cladding layers present on the substrate and defining at least one tunnel therein, at least one of the cladding layers being made of metal; a first dielectric layer disposed in the tunnel and having a first refractive index N1; a second dielectric layer disposed in the tunnel and having a second refractive index N2; and a third dielectric layer disposed in the tunnel and having a third refractive index N3, and N2>N1 and N2>N3, wherein the second dielectric layer is present between the first and third dielectric layers, wherein at least one of the cladding layers is present between the substrate and the first dielectric layer and protrudes toward the tunnel and away from the substrate, a portion of the first dielectric layer protrudes away from the substrate, and the second and third dielectric layers are conformal to the first dielectric layer.