【摘要】 利用米氏散射理论和时域有限差分(FDTD)软件计算了不同大小、形状和折射率粒子的前向散射光场分布,分析了通过光强度分布和非对称因子反演粒子相关信息、区分粒形的可行性。研制了一台利用增强型CCD相机在线采集单个气溶胶粒子在5°~19°前向散射角范围内光场图样的装置。8μm粒径的聚苯乙烯球形粒子散射图样实验结果与理论计算对比较为吻合,验证了该装置的有效性。应用该装置对不同形状的气溶胶粒子进行检测,结果表明能够从散射图像和反演计算结果区分出球形、杆状和其他形状粒子。更多还原

【Abstract】 The scattered light distributions of particles with different parameters of size, shape and refractive index are simulated with Mie theory and finite difference time domain(FDTD) software. The feasibility of particle shape inversed method with scattering intensity distribution and asymmetrical factor is discussed.Based on this result, a real- time aerosol particle shape identification device(RAPSID) is developed. It can collect the forward scattered light pattern with scattering angle from 5 to 19 degree by an ICCD camera. The pattern of an 8 μm polystyrene sphere particle is approximately consistent with the result of Mie scattering calculation, which verifies the accuracy of RAPSID. The test results of RAPSID for aerosol particles with different sizes show that particles of spherical, rhabdoid and other shapes can be distinguished from scattering image and inversed calculation results.更多还原