Patent ID: 7835610

Claim:
An optical waveguide, comprising: an optical waveguide formed on a substrate and configured to direct a light beam, wherein the waveguide has an inner area with a first index of refraction and an outer area with a second index of refraction, and wherein the optical waveguide has a loss of less than1 dB per meter; the inner area having a sufficient number of voids with a first dimension less than a wavelength of the light beam to enable the first index of refraction to be set at a predetermined level; and the outer area including a sufficient number of voids having a first dimension less than the wavelength of the light beam to enable the second index of refraction to be set at a level less than the first index of refraction wherein the first dimension of a plurality of the voids is less than 1/10 th of a shortest wavelength of the light beam.