Recent Developments on EOS 2-D/3-D Electron Gun and Collector Modeling Code

Recent developments on our electron optics simulator (EOS) are reported in this paper. EOS is the finite-element 2-D and 3-D steady-state beam trajectory codes which target problem classes, including axisymmetric guns, gridded guns, multibeam guns, and multistage depressed collectors at present. In order to improve the accuracy, to reduce computational time and computer memory consumption, and to extend the application scope, four significant advances to EOS have been made, and they are presented in this paper. The quadratic interpolation function, which has a higher accuracy than the linear interpolation function, is employed. A time-domain electrostatic model is built to simulate some transient effects. The symmetric computation algorithm and the 2-D model are applied for symmetric and axisymmetric structures to reduce the computational time and the computer memory consumption. Moreover, the results of the modified model and the original model are compared and analyzed in detail.