A New Surface Charge Method Used for Calculating Three Dimensional Potential Distribution
In calculation of potential in electrostatic lens based on surface charge method, conventional methods using constant, linear and quadratic function can not describe the distribution of charge density on singular geometry accurately where the quality of electrostatic lens' imaging is influenced largely by the precision of charge here. In order to solve the problem above, the new singular shape functions describing the distribution of charge density was proposed, based on the character of charge density on singular geometry according with the asymptotic trait, through incorporating singular terms into conventional singular shape functions. The calculated results on unit disc and double cylinder with singular geometry indicate that the improved method is more precise than the tradition one, which proves the method to be valid and feasible.
electron physicssurface charge methodpotential distributionsingular shape function
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维普
