Abstract
Electric field calculations have been improved in Japan. In the charge simulation method, disc charges have been introduced as fictitious charges. The method of conformal representation was also applied to the charge simulation method. The surface charge method was considered to be useful for various types of dielectrics. However, its application has been extended by simulating the surface charge density by means of Chebyshev polynomials. Curved-surface triangular and rectangular elements were also introduced in three-dimensional application of the surface charge method. The finite-element method is applied to the electric field including resistance, the ion flow field and the combination method. The electric field at a triple junction, where an electrode and two dielectrics meet at one point, has been investigated and the details of the electric field near the triple junction has been made clear.