Computational Optimization of the Radial and Spiral Distortion Aberration Coefficients of Magnetic Deflector Distortion

The optimum design of the magnetic deflector with the lowest values of the radial and spiral distortion aberration coefficients was computed. The optimized calculations were made using three models, Glaser bell-shaped, Grivet-lenz and exponential models. By using the optimum axial field distribution, the pole pieces shape which gave rise to those field distributions was found by using the reconstruction method. The calculations show that the results of the three models coincide at the lower values of the excitation parameter. In general the Glaser- bell shaped model gives the optimum results at the whole range of the excitation parameter under investigation. The negative values of the spiral distortion aberration coefficient appears in the results at the same case, therefore the designer can use it as corrector in other optical systems which suffer from this type of aberration.