xmpl3d41, 4-fold deflector, flat split-disc edgeways plates 


This is one of a set of 12 data files on electrostatic deflectors, listed in the comparison of deflectors.


The purpose of these files was to develop the ‘edgeways deflector’, see xmpxmpl3d42l3d42, which was the subject of the publication number 42:

 Edgeways electrostatic deflectors with reduced aberrations, by F H Read, Nucl. Instr. Meth. A427, 177-181 (1999).

The (unexpected) conclusion was that the 4-fold 'edgeways' deflector is much better than the conventional deflectors in current use (in 1999).


The present data file is based on xmpl3d35.  The 4 deflector plated are all sections of discs, as described there, but the inner radius is now 1.  There are similarities also with xmpl3d39, but now the lengths of the cylinders are effectively 0.

The rays start from a circle of radius 1 at z = -8 and converge to an axial point at z = 8.

The beam is deflected in the x direction.  The deflection voltage is such that the principal ray has x = 0.5 at z = 8.  Please refer to the data file itself for further information.


The program used to analyze the output data to deduce the aberration coefficients is called xmpl3d33_output in the programs list.


The results are summarised in the comparison of deflectors.