An optical signal, which is to become the subject of dispersion compensation,
is split by optical combining/splitting unit 2, and each frequency component
of the optical signal that is split is reflected by the corresponding reflective
mirror 30 included in reflective mirror group 3 to apply a predetermined
phase shift to the respective frequency components Each reflected frequency component
is then combined using optical combining/splitting unit 2, to give dispersion
compensated optical signal Furthermore, in regards to reflective mirror group 3,
which is used to apply phase shift to each frequency component of an optical signal,
each of the respective plurality of reflective mirrors 30 is made a movable
mirror having a movable reflection position that reflects the frequency components.
Through this, dispersion that develops in an optical signal may be compensated
with favorable controllability and high accuracy. Therefore, the precision and
controllability of dispersion compensation will become superior, and realized is
a variable dispersion compensator having a miniaturized optical circuit, and an
optical transmission system comprising such variable dispersion compensator,
