Design And Implement Of Polarization Image Acquisition System Based On FPGA

As polarization is an important characteristic of light, polarization image detecting is a new image detecting technology of combining polarimetric and image processing technology. Contrasting traditional image detecting in ray radiation, polarization image detecting could acquire some information which traditional image detecting couldn't. Polarization image detecting will be widely used in civilian field and military field. As polarization image detecting could resolve some problem which couldn't be resolved by traditional image detecting, it has been researched widely around the world. The article introduces polarization image detecting in physical theory at first, then especially introduces image collecting and polarization image acquiring based on FPGA.There are two parts including hardware and software are introduced for image collecting system in this paper. The theory of CMOS image sensor and the structure and PCB of real time image collecting system based on FPGA are introduced in the part of hardware. The PingPang buffer control in image buffer control is introduced in the part of software, as PingPang buffer control is necessary for real time image collecting and processing, and it is implemented by Verilog HDL. Stokes vector and polarization angle computing method are analyzed in the part of polarization image computing method. The float multiply of Stokes vector is optimized into just shift and addition operation. The computation of polarization angle includes reverse tangent function computation, an innovative lookup table arithmetic is given for computing reverse tangent function based on FPGA, and this arithmetic could be integrated and synthesized and realized by FPGA. The result of the experiment shows that real time image collecting system could collect image data from CMOS sensor in real-time. Stokes vector and reverse tangent function computing arithmetic is proven to be correct by the result of simulation.