Research On Polarization Controller Based On OptoCeramic

Polarization Controller (PC) is an indispensable component for state of polarization(SOP) control in optics communication and optical sensor systems. It requires fast response speed, big extinction ratio, small fluctuation with endless reset or reset-free SOP control. In this thesis, we successfully fabricate a type of high-speed polarization controller, which is based on transparent ferroelectric ceramics, and experimental data demonstrate its good performance.The current research situation of PCs and the kinds of PC models on market are described and compared. Mathematics models of SOP and the optical propagation characteristics in electric-optical crystal are reviewed. The properties of transparent ferroelectric ceramics of OptoCeramic? family such as high EO effect, low optical loss, broad transmission wavelength range and fast response time prove that the OptoCeramic? is the right material for PC . A polarimeter system based on USB2.0 is also developed to analyze the real time SOP and the performance of PC.A 4-plate electro-optic polarization controller is constructed with the plates fast axes oriented alternately 45°, 0°, 45° and 0° with respect to horizontal here. In this model, simulated annealing algorithm is adopted with some improvement: the parameters scale and T_k are determined by the intensity of feedback signal, which makes the system more stabile;the recovery issue based on mueller matrix and stokes vector theory is brought into the algorithm to come out a high quality initial solution,which makes the response faster. The experiment results show that the fluctuation of the light intensity in the desired output SOP is less than 4%, the angle deviation from desired SOP in degree is within 4, and the extinction is larger than 20 dB for a random input SOP.