极化聚合物薄膜电光系数的实时测量

Real Time Measurement of Electro-Optic Coefficient for Poled Polymer Film

提出了一种极化聚合物薄膜电光系数的实时测量方法。实验结构由耦合棱镜和依次制备在 棱镜底面的四层薄膜组成,这四层薄膜分别是金属层(作为上电极)、极化聚合物、缓冲层和下电极。包含导波共振角并具有一定角宽度的入射光线会聚于棱镜底面,然后用CCD探测器拍摄反射光斑,当外加电场作用于上下电极时,就可从光斑暗线位置的变化测量极化聚合物薄膜的电光系数。在测量过程中,使用了计算机图像处理方法和光学空间滤波技术。

A real-time measuring method for the electro-optic coefficient of the poled polymer film is proposed in the paper. The experimental structure consists of a coupling prism and 4-layer film that prepared on the prism bottom in proper order. These 4-layer films are metal layer (used as upper electrode), poled polymer, cushion layer and bottom electrode, respectively. It consists of guided-wave resonant angle and an incident light converges on the bottom surface of the prism with certain angular width. Then the reflecting light spot is photographed with CCD detector. When the applied electric field acts on both the upper and lower electrodes, the electro-optic coefficient of the poled polymer film can be measured according to the variations of the dark line position in the light spot. The image processing method with a computer and optical spatial filtering techniques are applied during the measurement.