TEM中电子衍射相机长度的实验分析及计算

透射式电子显微镜(Transm isson E lectron M icroscopy,TEM)中的电子衍射相机长度,是电子显微镜设计和对微晶体样品进行电子衍射分析的主要技术参数之一.依据布拉格(B ragg)定律,经对TEM中电子衍射成像光路的探讨与研究,并通过TEM与普通电子衍射仪的电子衍射的对比分析,导出了TEM电子衍射相机长度的精确计算公式,阐述了TEM和普通电子衍射仪的电子衍射相机长度所表征的物理意义的区别.同时对TEM中的电子衍射分辨率指数进行了分析和讨论,并给出了实际应用金单晶标样精确标定TEM电子衍射相机长度的实验方法.

Experimental Analysis and Calculation of Electron Diffraction Cameral Length in TEM

The camera length of electron diffraction in transmisson electron microscopy(TEM) is one of the main technical parameters in designing electron microscope and the electron diffraction analysis to microcrystal sample.According to Bragg law,the formula of calculating TEM electron diffraction camera length is derived from the(research) on the ray path of electron diffraction images in TEM and the comparison on electron diffraction with ordinary electronic diffractometer.The difference of physical significance of electron diffraction camera length between TEM and ordinary electronic diffractometer is discussed.The resolution index of electron diffraction in TEM is analyzed.The exactly experimental method is given for demarcating electron diffraction camera length by Gold-monocrystal in TEM.