OPTICAL CIRCUIT ELEMENT AND PRODUCTION METHOD THEREFOR, ARRAY-FORM OPTICAL CIRCUIT ELEMENT, OPTICAL CIRCUIT DEVICE USING IT

摘要

A method of monitoring a propagation light propagating through each waveguide in an array waveguide device. Problems with picking up a monitor light in a waveguide substrate and receiving it are resolved in the following ways. A waveguide type directional coupler is formed in a space between array waveguides, part of a propagation light is picked up as a monitor light, a recessed portion is provided at the end of a waveguide continuous from the directional coupler to allow the monitor light to be output to this recessed portion and to be reflected to the upper or lower portion of the substrate by means of an optical path conversion element mounted in the recessed portion, and then it is received at a photodiode. The optical path conversion element is obtained by inserting a metal block into the recessed portion and then molding it in a mold.