OPTICAL WAVEGUIDE SUBSTRATE AND HARMONICS GENERATING DEVICE

摘要

An optical waveguide substrate having a ridge type optical waveguide, wherein a structure capable of reducing loss to be incurred when an incident light propagates through a three-dimensional optical waveguide is provided. The optical wavegide substrate comprises a ferroelectric layer (3) consisting of a ferroelectric material, a ridge unit formed on the surface of the ferroelectric layer (3), protrusions respectively provided on the opposite sides of the ridge unit, and a three-dimensional optical waveguide provided on the ridge unit. Alternatively, the substrate comprises a ridge unit (15) formed on the surface of the ferroelectric layer (3), step differences (25A, 25B) respectively provided on the opposite sides of the ridge unit (15) and being lower than the ridge unit (15), grooves (16) respectively formed on the outer sides of respective step differences, and a three-dimensional optical waveguide provided on the ridge unit (15).