Optimization of Screening Correction in Difference Model of Stationary Electric Field

Some questions of optimization of the screening task solution have been considered. A screening simple layer-shaped corrections both located nearby the boundary of area to be shielded and distant were obtained. These corrections include charges with absolute values that remains limited, while absolute values of nonoptimal correction charges increase as O(1/h), where h-step of grid. At the beginning we've briefly represented the difference potential method and general solution of screening task, obtained by V.S. Ryaben'kii.