Patent ID: 7590356
Filing Date: 2009-09-15
Classification: G02B

Abstract:
1. A variable dispersion compensator comprising: a first variable dispersion compensating unit that includes a first optical resonator receiving a light beam emitted from a collimator and a first mirror disposed with a predetermined angle relative to the first optical resonator, and that reflects the light beam n a second variable dispersion compensating unit that includes a second optical resonator receiving the light beam emitted from a collimator and a second mirror disposed with a predetermined angle relative to the second optical resonator, and that reflects the light beam n a third variable dispersion compensating unit that includes a third optical resonator receiving the light beam emitted from a collimator; wherein: the first and second optical resonators each have a first and second plane surfaces that are opposed to each other, the first plane surface having a reflectance of 90% or more and 100% or less, and the second plane surface having a reflectance lower than the reflectance of the first plane surface; when the shortest wavelength within a wavelength band of a multiplexed optical signal incident on the second plane surface is a first wavelength, and the longest wavelength within the wavelength band is a second wavelength, a reflectance of light with the first wavelength and a reflectance of light with the second wavelength are different from each other on the second plane surface; a filter is disposed on the second plane surface, the filter being designed such that the value of a reflectance is monotonously increased or monotonously decreased between the first and second wavelengths; and the first variable dispersion compensating unit, the second variable dispersion compensating unit and the third variable dispersion compensating unit are cascade-connected.