Traditional laser particle sizing device based on Fraunhofer diffraction theory which is widely used for simple calculations, but its application is limited for the smaller measurement scope.

• 传统的激光粒度测试仪基于夫琅和费衍射理论原理进行粒度测量，该理论由于计算简单快捷而被广泛采用，但该理论测量范围较小的缺陷严重的限制了它的应用范围。