Optical coupler with polarity separation

摘要

The coupler/separator has coplanar waveguides (11, 13) whose two adjacent portions are extended along a same direction. An intercalated guide segment is extended between the coplanar waveguides, where a side (16) of the intercalated guide segment is rectilinear. One of the portions comprises a constant section and the other portion comprises a variable section such that the effective index of the latter portion is passed from upstream to downstream, where the effective index of the latter portion is lower than the effective index value of the former portion.