针对多角度动态光散射中角度组合对颗粒粒度分布测量的影响,对5组模拟的双峰分布颗粒体系(114/457 nm,202/800 nm,307/541 nm,433/721 nm和600/900 nm)分别选取3、4、5和6个散射角,采用不同角度组合进行测量.粒度反演结果表明,在选取同样数量散射角条件下,不同的角度组合会得到不同的测量结果.当选取的各散射角对应的Mie散射光强差异显著,特别是对应光强值包含了Mie散射光强曲线的极大值和极小值点时,测量结果更准确.采用标准聚苯乙烯乳胶颗粒进行的测量实验,实验结果与反演结果一致.这种角度组合影响的原因在于,随着散射角的增多,得到的颗粒粒度信息也相应增加,但只有增加的散射角所对应的散射光强显著不同时,才会较多地增加颗粒粒度信息,从而改善测量效果;否则,增加的信息会被增加的角度校准噪声所抵消.
In order to analyse the influence of the angular combination on the dynamic light scattering measurement,five groups of simulated bimodal particle system(114/457 nm,202/800 nm,307/541 nm,433/721 nm and 600/900 nm) were measured at different combinations of three,four,five and six scattering angles respectively.The inversion results show that,the different angular combinations with the same numbers of scattering angles give different measuring results.When Mie-scattering intensitys corresponded to the selected angles are different significantly,especially including the maximum and minimum points,the more accurate measurement results can be gotten.The results were verified by the experimental results of a dilute bimodal suspension of polystyrene latex standard spheres.The reason for the combination influence is that the information of particle sizing is added as the number of scattering angle increases,but only when the added angles located at the points of Mie-scattering intensity different significantly would provide more information about particle sizing.However,if improper angles are choose,the benefits from increase of angles would be offset by the losses caused by angle calibration noise.