2D calculation of parasitic fields in misaligned multipole electron-optical systems.

The effects of geometrical imperfections in electron-optical components are usually evaluated in 3D simulations. These calculations inherently take a long time, require a large amount of memory, and do not directly produce the necessary axial field functions. We present a 2D perturbation method to calculate parasitic fields in misaligned multipole systems.

Accurate interpolation of 3D fields in charged particle optics.

Standard 3D interpolation polynomials often suffer from numerical errors of the calculated field and lack of node points in the 3D solution. We introduce a novel method for accurate and smooth interpolation of arbitrary electromagnetic fields in the vicinity of the optical axis valid up to 90% of the bore radius. Our method combines Fourier analysis and Gaussian wavelet interpolation and provides the axial multipole field functions and their derivatives analytically.