Patent ID: 8737777

Claim:
An optical waveguide having a curved section in which, in the curved section, the waveguide has an asymmetric refractive index profile, in which the refractive index varies asymmetrically across the cross-section of the waveguide in dependence on the radius of the curved section of the waveguide; wherein the waveguide is a cylindrically curved waveguide and the refractive index for the curved section varies based on a perturbation determined in accordance with the following formula: n p = n o · R T r in which r is the radial distance from the origin of the cylindrically curved waveguide at which the perturbed refractive index is calculated; R T is the constant value for the outer bend radius of the waveguide; n p is the calculated perturbed refractive index; and n o is the original unperturbed refractive index.