The article focuses on studies of spectrographic structures being useful for energy analysis of charged particles. These structures are electrostatic fields which possess a main feature of spatial separation of a secondary charged particles flow being analyzed, into some monoenergetic beams. The availability of similar charged particle trajectories in electrostatic fields is a necessary condition for realization of spectrographic mode. Such flow separation is typical not only for electrostatic fields with potentials being homogeneous functions in Euler sense, but also for other structures. A class of general homogeneous functions with logarithmical singularity has been considered. In these fields a similarity concept is obeyed approximately. A general analytical expression for the potential structures is given, and an evaluation criterion for breaking similar tracks is formulated. A technique for creating potential structures is presented; it allows building effective electrostatic spectrographs. The surfaces of equal potentials of some concrete realizations are presented. An outlook for the spectrographs use is discussed.