Fuzzy optimization of an electron optical lens

In ordinary optimum methods, the geometric parameters and electric parameters are constrained in some closed intervals. From the view of engineering, the physical variables which give some definite boundaries are not strictly constrained, so this paper proposes the fuzzy optimization of an electron optical lens. In this method, the constraints of the structure parameters and the electric parameters are considered as fuzzy intervals in a real field. A fuzzy optimum set has also been obtained. A four electrodes extended field lens (4EFL) is taken as an example to be fuzzy optimized, and the curve of optimal points in the 4EFL is plotted in this paper. Because this method has taken account of the fuzzy factors, its result will fit with the practical condition properly.