Practical Electron Microscopy and Database

Figure 4277 shows schematic illustration of the rotationally symmetric magnetic fields and the electron lenses. According to Newton’s law, the differential equations for the electron trajectories in the cylindrical coordinate system r, φ, z can be given by,

               (radial component) ------------------------ [4277a]

               (circular component) ------------------------------- [4277b]

               (longitudinal component) --------------------------------- [4277c]

The last term in Equation 4277a provides the centrifugal force.

Figure 4277. Schematic illustration of rotationally symmetric magnetic fields and electron lenses.