INTEGRATED OPTICAL DEVICE WITH MODE SHAPE CONVERTER AND MANUFACTURING METHOD THEROF

摘要

PURPOSE: A mode shape converter with double rib waveguides formed on a same material and its manufacturing method are described. A mode shape converter is inserted between an input and an output port of an integrated optical device, which reduces a coupling loss. CONSTITUTION: A mode shape converter comprises a base substrate(300), a lower cladding layer(302), a lower rib waveguide(304), an upper rib waveguide(308), a core layer and an upper cladding layer(310). The converter consists of a coupling region(312) having the double rib waveguides formed on a core layer, a conversion region(314), and a stabilization region(316). A tapered rib waveguide has an up-tapering structure made of same material. The coupling region having a connection with optical fiber is designed to achieve a high efficiency. The conversion region converts the optical wave generated in the coupling region to fit the functions of the optical device. This region is designed to satisfy an adiabatic condition, which minimizes a radiation loss. The stabilization region having only an upper rib waveguide eliminates the high mode.