介绍了衍射散射式颗粒粒度测量法的基本光路结构和理论模型, 讨论了决定其性能优劣的重要指标--测量下限, 对影响测量下限向小粒径范围延伸的参数进行了分析。继而介绍了近年来国内外主要粒度仪品牌在光学结构和散射理论模型方面所做的改进, 阐述了它们的工作原理和性能特点。最后对衍射散射式颗粒粒度测量法的发展前景做出了展望, 从修正理论模型、改进反演算法、提高探测器性能、缩小测量系统体积等几个角度提出了改进的想法和实例, 并介绍了一种称为后向散射光谱傅里叶分析法的新方法, 此方法有望大幅延伸测量下限。

The theoretical model and the basic optical structure of the particle size measurement by laser diffraction and scattering are introduced. The lower limit of measurement --an important indicator of the performance of this method is discussed. Parameters which prevent the lower limit from extending to the small size are analyzed. The improvements on optical structures and theoretical model of several major commercial particle size analyzers in recent years are described then. Future prospects of this measurement are presented in the field of theoretical model correction, inversion algorithm modification, detector improvement and volume compaction. In addition, a new method named particle size measurement by backscattering spectroscopy and Fourier analysis is introduced, which is expected to extend the lower limit significantly.