抄録
This paper describes a new fast optical polarization control system by a z-propagating LN (LiNbO3) crystal with four electrodes on the x and y cut surface. In order to stabilize the fluctuating polarization to right circular polarization, the orthogonal voltages Vx and Vy are applied to the corresponding electrodes, which are directly calculated from the Stokes parameters of input light tapped by a 3:1 divider. The size of the LN element is 1.5×1.5×40mm and the electrode width is optimized as 0.7mm, which is enough to minimize the distortion of electric filed distribution. As the experimental results, all insertion loss was 2.9dB including the tapped loss, polarization extinction ratio was 24dB by the polarization state. The cycle of control was 60kHz using a personal computer. The endless control function is also achieved by making the limit of the maximum change of the angle due to the ratio of Vx and Vy.
