| 摘要 |
PURPOSE:To obtain the optical waveguide which has a high confining effect, exhibits a low propagation loss and is excellent in high electrooptical effect. CONSTITUTION:While the optical waveguide matched in the lattice of a substrate crystal and the crystal of a thin-film waveguide layer 2 is produced, this waveguide is constituted into a ridge type 1 or rib type having a relation 6.0X10<-2=W/T<=0.7X10<2> between the thickness T(mum) of the thin-film waveguide layer 2 and the width W(mum) of the thin-film waveguide layer 2. Particularly the optical waveguide of the ridge type is so designed as to have a relation 0.10<=t/T<=0.99 where the level difference of the ridge is designated as t. |
