LIQUID-CRYSTAL ROTATABLE WAVEPLATES

We propose and demonstrate rotatable waveplates using liquid crystal f or the first time which can be used for polarization control. To reali ze a waveplate with an arbitrary direction of birefringence, we use a vertically-aligned nematic liquid crystal cell with a lateral electric field. The orientation of the waveplate can be rotated endlessly. It was confirmed that the direction of the waveplate could be rotated end lessly at a rate of 7200 degrees/s, which is sufficient to construct p olarization controlling devices for most SMF transmission systems.