Patent ID: 7221872

Claim:
An on-line dispersion compensation device for a wavelength division optical transmission system, comprising: two 2*2 optical couplers, and two chirped grating fiber units, serially connected between the two optical couplers, respectively; which are used for selecting, reflecting and dispersion compensating at least one wavelength inputted and bypassing other wavelengths inputted; wherein first ports of the two chirped grating fiber units is respectively connected with two arms of a first port of the first optical coupler; second ports of the two chirped grating fiber units is respectively connected with two arms of a first port of the second coupler; one arm of a second port of the first coupler is connected with the optical signal input of the device; one arm of a second port of the second coupler is connected with the optical signal output of the device; and the other arm of the second port of the first coupler is connected with the other arm of the second port of the second coupler.