Patent ID: 7558456

Claim:
An optical waveguide device comprising: a lower cladding layer; a high refractive index region provided on the lower cladding layer; a pair of cores provided on the lower cladding layer on both sides of the high refractive index region; an upper cladding layer provided on the high refractive index region and the pair of cores; and a leak light blocking band traversing the high refractive index region and having each end connected to one of a pair of band-shaped parts adjacent to the pair of cores; wherein one of the upper and lower cladding layers has the band-shaped parts disposed between the high refractive index region and the pair of cores, the upper and lower cladding layers have a refractive index n 2 , the high refractive region has a refractive index n 3 satisfying a relationship n 3 >n 2 , and a refractive index of the leak light blocking band is smaller than a refractive index of the pair of cores.