Temperature-compensated optical communication interference device and optical communication system

摘要

The invention relates to a temperature-compensated optical communication interference device. In this device, an optical divider divides light entering an input port into two light beams. An optical coupler superposes these beams and feeds the superposed light to an output port. First and second optical paths are provided between the divider and the coupler. First and second optical components are placed on the first and second optical paths, respectively. The divider, coupler, and optical components are placed on a substrate. The substrate has members with coefficients of linear expansion having different signs. Temperature dependence of an optical path length difference between the first and second paths is reduced due to the difference between the signs of the coefficients.