This looks like the most hideous example of an electrostatic lens, and it was analyzed in the
AbstractBook of CPO7 in Cambridge.
How cathode is defined (already by Munro) is worth noticing. Why? The field would be bad on the
cathode (it is discontinuous). No comparison with published data is possible (see also
www.mebs.co.uk) - there are no details about the initial conditions so that we can also trace
our own pictures, and trust them if they look the same for different mesh sizes. In order to
calculate the whole region in one go, it is naturally necessary to use many points, around a
million. But there is no problem to use four times as many points and redo the computation
and analyze the accuracy of potential and field.
|
