Patent ID: 6546163
Filing Date: 2003-04-08
Classification: G02B,G02F

Abstract:
An integrated optic switch capable of redirecting optical beams in a planar waveguide geometry comprising:an optical planar waveguide structure including a lower cladding layer, a core layer having means for introducing an incident optical beam therein to, a trench formed in said core layer, an upper cladding layer, and a temperature control element; said trench extending at least substantially through the thickness of said core layer, said trench being filled with a liquid crystal material, said liquid crystal, and said core layer having refractive indices that are at least substantially matched at a temperature at which said liquid crystal material is in its isotropic phase, said liquid crystal filled trench being covered by said upper cladding layer, said temperature control element disposed at a location above said liquid crystal filled trench, said liquid crystal having its director aligned along the long dimension of said trench when said liquid crystal is in its nematic phase, said liquid crystal material having positive birefringence so that the ordinary refractive index of said liquid crystal material in said nematic phase is lower than said isotropic refractive index as well as said core layer refractive index, the angle of incidence of an incident optical beam passing through said core layer and onto said liquid crystal filled trench being larger than that needed for total reflection of said optical beam from the interface between said core layer and said liquid crystal material when said liquid crystal material is in said nematic phase, said temperature control element having the capability of holding said liquid crystal filled trench at said temperature at which said liquid crystal material is in said nematic phase so that said optical beam is redirected by reflection from said interface so that said optic switch is in its ON state, said temperature control element alternatively having the capability of holding said liquid crystal filled trench at said temperature at which said liquid crystal material is in said isotropic phase so that said optical beam is transmitted through said liquid crystal filled trench so that said optic switch is in its OFF state.