An optical signal may be received into orthogonal linearly polarized modes of
a transmission optical waveguide, the transmission waveguide including first and
second transverse-coupling segments thereof. Optical signal polarized along one
polarization direction may be substantially completely transferred from the transmission
waveguide into a first transverse-coupled waveguide, the first transverse-coupled
waveguide being optically transverse-coupled to the first transverse-coupling segment
of the transmission waveguide. Optical signal polarized along the other polarization
direction may be substantially completely transferred from the transmission waveguide
into a second transverse-coupled waveguide, the second transverse-coupled waveguide
being optically transverse-coupled to the second transverse-coupling segment of
the transmission waveguide. The optical signals carried by the first and second
transverse-coupled waveguides may be combined into a single waveguide. The polarization
directions of the transmission waveguide may be rotated about 90 between
the first and second transverse-coupling segments.
