The Effect of Coil Geometry and Magnetic Circuit on the Flux Lines Trajectory of the Magnetic Lenses

The present research includes studying the effect of position and geometrical shape of the coil on magnetic flux lines trajectory also on the shape of the magnetic flux density distribution of a single polepiece lens where by its objective focal properties were designed and studied previously by researchers. It has been noticed that the change in coil position in comparison with the original design causes important improvement in the magnetic flux lines distribution inside the structure of the lens and clearly increasing the value of the magnetic flux density peak. Besides, the conical and vertical iron shroud was introduced to the original lens giving a clear effect in improving the lens performance and magnetic flux lines path, furthermore, increasing the magnetic flux peak as well as decreasing the half-width as a result the objective focal properties of the lens lead to a large improvement in lens performance comparing with the optical properties of the original lens design.