不规则粗糙粒子广泛存在于粒子场中, 为获得其尺寸信息, 建立激光干涉成像系统, 提出了不规则粗糙粒子尺寸计算方法。基于光学传输矩阵理论, 模拟了不规则粗糙粒子激光干涉离焦像, 分析得到粒子尺寸与离焦像2D自相关的关系, 给出不规则粗糙粒子尺寸计算公式。以砂砾为样本进行激光干涉成像实验, 采集不同转向下的离焦像并进行频率分析获得粒子尺寸, 实验结果表明, 测量误差不超过10.4%, 满足微小粒子的测量要求, 对实际粒子场的测量具有重要意义。

Irregular rough particles widely exist in the particle fields. In order to obtain the size information of the particles, a laser interferometric imaging system is established, and an irregular rough particle size calculation method is proposed. Based on the theory of optical transfer matrix, the laser interferometric defocused images of irregular rough particles are simulated, and the formula for calculating irregular particle size is given by the relation between particle size and 2D autocorrelation of defocused image. Sand particles are chosen as the sample to carry out a laser interferometric imaging experiment, and the defocused images under different steering are collected and the frequency analysis is carried out to obtain the particle size. The experimental results show that the measurement error does not exceed 10.4%, which satisfies the measurement requirement of micro-particles, and is of great significance for the measurement of actual particle fields.