THERMOOPTICAL SWITCH, MANUFACTURE THEREOF AND OPTICAL LINE CHANGING METHOD USING THE SWITCH

摘要

PROBLEM TO BE SOLVED: To provide a thermooptical switch which has small coupling losses with optical fibers and power to drive the switch is small and which has a speed equal to or smaller than several hundreds ofμm. SOLUTION: This switch includes a substrate 510, a lower part clad layer 520 on which an input taper converting the circular mode inputted from an optical fiber into an elliptic mode having a rib structure is formed at an input end and output tapers converting the elliptic mode having a rib structure into a circular mode to in-put the mode to optical fibers are formed at output ends, a core layer 530 which is formed on the lower part layer 520 and in which a branched waveguide having the rib structure, through which the elliptic mode outputted from the input taper is transmitted and from which the transmitted elliptic mode is outputted from the output tapers is formed, an upper part clad layer 540 which is formed on the core layer 530 and electrodes formed on the upper side clad layer 530 for switching, so that the elliptic mode is selectively branched by the effective refractive index difference between the branched waveguides having the rib structure, while applying heat to the branched waveguides having the rib structure.