Welcome!

Traceon is a general software package used for numerical electron optics. Its main feature is the implementation of the Boundary Element Method (BEM) to quickly calculate the surface charge distribution. The program supports both radial symmetry and general three-dimensional geometries. Electron tracing can be done very quickly using accurate radial series interpolation in both geometries. The electron trajectories obtained can help determine the aberrations of the optical components under study.

If you have any issues using the package, please open an issue on the Traceon Github page.

The software is currently distributed under the MPL 2.0 license.

Usage

In general, one starts with the traceon.geometry module to create a mesh. For the BEM only the boundary of electrodes needs to be meshed. So in 2D (radial symmetry) the mesh consists of line elements while in 3D the mesh consists of triangles. Next, one specifies a suitable excitation (voltages) using the traceon.excitation module. The excited geometry can then be passed to the solve_direct() function, which computes the resulting field. The field can be passed to the Tracer class to compute the trajectory of electrons moving through the field.

Validations

To make sure the software is correct, various problems from the literature with known solutions are analyzed using the Traceon software and the results compared. In this manner it has been shown that the software produces very accurate results very quickly. The validations can be found in the /validations directory in the Github project. After installing Traceon, the validations can be executed as follows:

    git clone https://github.com/leon-vv/Traceon
    cd traceon
    python3 ./validation/edwards2007.py --help

Units

SI units are used throughout the codebase. Except for charge, which is stored as $\frac{ \sigma}{ \epsilon_0}$.

Sub-modules

traceon.excitation

The excitation module allows to specify the excitation (or element types) of the different physical groups (electrodes) created with the …

traceon.focus

Module containing a single function to find the focus of a beam of electron trajecories.

traceon.geometry

The geometry module allows the creation of general meshes in 2D and 3D. The builtin mesher uses so called parametric meshes, meaning that for any …

traceon.interpolation

traceon.logging

traceon.mesher

traceon.plotting

The traceon.plotting module uses the vedo plotting library to provide some convenience functions to show the line and triangle meshes generated by …

traceon.solver

The solver module uses the Boundary Element Method (BEM) to compute the surface charge distribution of a given geometry and excitation. Once the …

traceon.tracing

The tracing module allows to trace charged particles within any field type returned by the traceon.solver module. The tracing algorithm used is RK45 …