Patent ID: 9366938
Filing Date: 2016-06-14
CPC Classification: G02F

Claim Text:
1. A waveguide for controllably steering a light beam, wherein the waveguide is characterized by an effective index of refraction, the waveguide comprising: a substantially planar core through which the light beam propagates; at least one top-cladding having a liquid crystal material therein, the at least one top cladding adjacent to the substantially planar core; at least one bottom-cladding adjacent the substantially planar core such that the substantially planar core is between the at least one top-cladding and the at least one bottom-cladding, the at least one bottom-cladding having no liquid crystal material; at least one optically transparent substrate to structurally support the core and the at least one top-cladding, the at least one optically transparent substrate providing an out-coupling medium to receive light from the substantially planar core; at least one out-coupling medium positioned with the at least one bottom-cladding between the substrate and the core, the at least one out-coupling medium having an index of refraction that is larger than the effective index of refraction of the waveguide, wherein the out-coupling medium is separated from the core within the waveguide by the bottom cladding, wherein a thickness of the bottom cladding decreases from a first thickness near the input end of the waveguide to a second thickness near the output end of the waveguide such that an evanescent tail of the light in the core penetrates into the out-coupling medium and such that light transmits from the substantially planar core into the out-coupling medium at an out-of-plane propagation angle formed with respect to a plane of the substantially planar core and the at least one cladding; at least one facet on the out-coupling medium oriented at an angle with respect to the substantially planar core such that the light that has left the substantially planar core passes through the out-coupling medium and impinges on the at least one facet, wherein the light then leaves the waveguide through the at least one facet in an out-of-plane propagation angle; and at least one electrode for receiving at least one voltage selected to control the magnitude of the propagation angle.