▎ 摘　　要

In order to clarify the existence of a single sheet of carbon six-membered-ring, plane (graphene). this letter presents a method by which the stacking number of the sheets in a carbon nanofilm (CNF) can be exactly counted, based on the quantitative analysis of electron diffraction intensity. Using the method we can detect a single graphene sheet in a CNF. (C) 2004 American Institute of Physics.