Electron Diffraction and Convergent Beam Electron Diffraction (CBED)—Basis for the Formation of Lattice Fringes in TEM and Image Intensity of STEM

A transmissionElectron diffraction (ED) electron microscope (TEMTransmission electron microscope (TEM)) is based on diffraction phenomenaDiffraction phenomena in specimensConvergent Beam Electron Diffraction (CBED) and image formation by an electromagnetic lens as a convex lensConvex lens. For thin specimens and single atoms, we can use “phase object approximation (POAPhase object approximation (POA))” and “weak-phase object approximation (WPOAWeak phase object approximation (WPOA)).”