激光衍射粒度测量中的旋滤波方法

Spin filtering method in particle size measurement based on laser diffraction

激光衍射法测量颗粒粒径过程中，面阵CCD接收到的待测颗粒的衍射图样总是不可避免受到噪声污染，直接影响粒度的反演精度。通过对测试原理及衍射图样的深入分析，提出了采用曲线窗口旋滤波对衍射图样进行预处理的方法，并进行了粒子群粒度反演的数值模拟实验。经过旋滤波处理后的单峰粒子和双峰粒子的粒度分布误差从直接粒度反演的42．36％、46．099／6和39．06％、35．7％分别减小到5．3％、6．17％和6．48％、7．33％，实验结果证明了采用曲线窗口旋滤波方法，粒度分布误差明显降低。

To measure particle size based on laser diffraction method, the diffraction patterns received by area CCD does not avoid being disturbed by all kinds of random noises in practice. The noises can influence inversion precision of the particle size directly. With a through analysis of particle measuring principle and diffraction patterns, a kind of filtering method is put forward for diffraction patterns based on spin filtering, numerical simulated experiments of particle size measurement are made. The diffraction patterns of one peak and two peaks by using spin filtering, which of its particle size distribution errors are reduced from 42. 36%, 46.09% and 39.06%,35. 7% to 5.3%,6. 17% and 6. 48%,7. 33%. The inversion results of the particles simulated experiment prove that using the spin filter with curve windows is effective in reducing particle size distribution error.