DISPRESION COMPENSATOR

摘要

PURPOSE:To provide a dispersion compensator which hardly generates polarization dispersion. CONSTITUTION:A dispersion compensation optical fiber 3 having a negative dispersion characteristic generated by the refractive index distribution of a core is coiled to form a dispersion compensation optical fiber coil 6 and a double refractive optical fiber 8 having the polarization dispersion value of nearly the same quantity as the polarization dispersion value of this dispersion compensation optical fiber coil 6 is connected to the dispersion compensation optical fiber coil 6. A slow axis and fast axis which are polarization component axes varying in propagation rates of light are respectively formed due to the respective polarization dispersion values in the dispersion compensation optical fiber coil 6 and the double refractive optical fiber 8 and, therefore, the dispersion compensation optical fiber coil 6 and the double refractive optical fiber 8 are so connected that the slow axis of the double refractive optical fiber 8 and the fast axis of the dispersion compensation optical fiber coil 6 are aligned to each other and that the fast axis of the double refractive optical fiber 8 and the slow axis of the dispersion compensation optical fiber coil 6 are aligned to each other at the time of connecting the dispersion compensation optical fiber coil and the double refractive optical fiber 8.