基于FPGA的光偏振方向测量系统研究

Measurement System of Light Polarization Direction Based on FPGA

针对偏振调制测量旋光介质溶液浓度需通过线偏振光的偏振方向测量旋光度这一需求,提出了小型便携式光的偏振方向测量系统。以FPGA作为主控芯片,驱动摄像头采集图像,利用灰度、二值化和形态学图像处理的模块对图像进行处理,使用DDR3的两个BANK地址缓存摄像头提供视频图像和捕捉待处理图像数据,通过显示屏实时监测选择合适的图像进行捕捉,对DDR3缓存的待处理图像进行读取,根据图像的二阶中心矩公式,计算偏振方向角,由数码管显示角度数据。实验结果表明,该方法测量偏振方向弥补了目前测量偏振方向的实时性、便携性的不足,测量准确度也得到了提高。

For measuring the concentration of optically active medium solution by polarization modulation,it is necessary to measure the optical rotation by the polarization direction of linearly polarized light.A portable measurement system for polarization direction of light is presented in this paper.FPGA is used as the main control chip to drive the camera to collect images.Gray scale,binarization and morphological image processing modules are used for image processing.Two BANK address cache cameras of DDR3 are used to provide video images and capture image data to be processed.The image to be processed by DDR3 cache is read,and the polarization angle is calculated according to the second order center moment formula of the image,and the angle data is displayed by the digital tube.The experimental results show that this method makes up for the shortage of real-time and portable measurement of polarization direction.The measurement accuracy is also improved.