双光束照明的干涉粒子成像粒子尺寸测量

Particle Sizing by Interferometric Particle Imaging with Two Lights Illumination

设计一种两光束相向照射,在散射角θ=90°方向记录的干涉粒子成像测量实验系统,利用模版匹配相关方法提取粒子两点像的位置坐标,根据粒子像位置坐标,粒子掩模图的形状和大小提取出单个粒子两点像。再对每个粒子两点像进行自相关、Gaussian插值提取两点像之间距离,进而计算得到粒子尺寸大小,其测量精度可达到亚像素精度。对标称值为45 mm的标准粒子进行了测量,粒径测量值为(46.54±0.50)mm,相对误差3.42%。实验结果表明了该方法的可行性。

An experimental system of interferometric illumination at scattering angle θ=90° is presented. The particle imaging with opposition of two laser-sheets center of particle imaged can be extracted through the template matching correlation operation between the particle focused images and the particle mask image. The focused image of each particle can then be achieved by using the center coordinate, the shape and size of the particle mask image. The spacing of the doublet image of the individual particle is evaluated by the auto-correlation method and Gaussian interpolation, and sub-pixel accuracy of the glare point separation extraction is acquired. Then particle diameter is calculated. The result is that for particle diameter （46.54 ± 0.50） μm, the relative error is 3.42% for the standard particles with diameter of 45 μm. The research results show that the experimental system and algorithm presented in this paper are feasible.