Polarization scrambler and integrated optical circuit making use thereof

DETAILED DESCRIPTION What is claimed is: 1.
A polarization scrambler comprising: a first splitter for splitting an incident signal light into two; a first optical path which is made of a material having an electrooptical effect and through which one of the signal light split by said first splitter is propagated; a second optical path which is made of a material having an electrooptical effect and through which the other signal light split by said first splitter is propagated; a first voltage supplier which applies a voltage to at least one of sections set in said first optical path and said second optical path for varying a phase of a signal light propagated through the section; a first coupler which combines signal lights propagated through said first optical path and said second optical path; and a first plane-of-polarization rotator which rotates a polarization of the signal light in at least one of said first optical path and said second optical path between said section and said first coupler for adjusting a relative polarization angle between signal lights propagated through said first optical path and said second optical path.
2.
A polarization scrambler according to claim 1 wherein said first plane-of-polarization rotator adjusts the relative polarization angle between said signal lights around 90.
degree.
.
3.
A polarization scrambler according to claim 2 wherein said first plane-of-polarization rotator comprises a first rotor in one of said first optical path and said second optical path between said section and said first coupler, and said first rotor rotates a polarization of the signal light approximately 90.
degree.
.
4.
A polarization scrambler according to claim 2 wherein said first plane-of-polarization rotator comprises a second rotor and a third rotor in said first optical path and said second optical path between said predetermined section and said coupler, one of said second rotor and said third rotor rotates a polarization of the signal light approximately 45.
degree.
, and the other rotor rotates a polarization of the signal light approximately -45