Patent ID: 7206513

Claim:
A polarization mode dispersion compensation apparatus using a photonic crystal structure in a system transmitting optical signals through optical fibers, comprising: an optical signal splitter for splitting incident optical signals into optical signals of a first polarization state and a second polarization state, which are perpendicular to each other in polarization directions, and for outputting the split optical signals in different directions; an optical signal combiner for combining into a single direction the optical signal of the first polarization state with the optical signal of the second polarization state, both of which being incident from a different direction, and for outputting the combined signal; an optical signal guide having a photonic crystal structure having a first waveguide for guiding the optical signals outputted from the optical signal splitter to the optical signal combiner in a first path and a second waveguide for guiding the optical signals outputted from the optical signal splitter to the optical signal combiner in a second path, wherein the first path is the shortest path and the second path is longer than the first path by a predetermined distance; a medium forming an inside of the second waveguide; a signal tab for externally outputting a portion of the optical signals outputted from the optical signal combiner and for outputting a portion of the optical signals to a feedback unit; a feedback unit for measuring a dispersion degree of the first polarization state and the second polarization state of the optical signals inputted from the signal tab, and for outputting a feedback signal for removing the polarization mode dispersion based on a result of the measurement; and an effective optical path length variation unit capable of varying an effective optical path length of the second path for the optical signals passing through the second waveguide based on the feedback signal outputted from the feedback unit by modifying a refractive index of the medium inside the second waveguide.