Charged-particle ray trace Decorative artwork in the style of a CPO simulation plot: charged-particle trajectories, drawn as fine lines, converge through a crossover at a focal point marked by a glowing dot — the kind of ray trace the CPO programs produce.

CPO2D · CPO3D · Boundary Element Method

Charged particle optics software

The CPO programs solve 2- and 3-dimensional electrostatic problems with the Boundary Element Method — exceptionally accurate, easy to use, and described as the gold standard of charged particle optics.

New · Free 64-bit editions

CPO2D and CPO3D are now free in 64-bit

We are delighted to announce that 64-bit versions of CPO software are now available for free. This version is perfect for students and those who wish to explore the software's functionality before purchasing the more powerful unlimited 64-bit version. It is built from the same code base as the unlimited version and can be installed without a license key or internet connection.

The free version does not include the following advanced features — if you need them, a 15-day evaluation unlocks every option while you decide whether to purchase the unlimited edition:

Large segment counts Scattering User cathode Dielectric Field import

Previously, only the 32-bit version was offered for free usage. Due to limitations of 32-bit applications we've taken the decision to no longer offer any 32-bit versions.

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The programs

World-beating programs for solving 2 and 3-dimensional electrostatic problems

The Boundary Element Method, BEM, deals with surface charges and has many advantages over the methods used in almost all other commercial programs. The programs were developed by Profs Frank Read and Nick Bowring, in the group at Manchester University which was the first to use the BEM in electron optics and which produced the definitive book Electrostatic Lenses, by Harting and Read. Frank has been joined by Ryan O'Neill, working on the further development of the software.

The programs have been described as the gold standard of charged particle optics. The CPO programs are exceptionally accurate and have many advanced options that are not present in other programs. If you would like to be kept up to date with new releases, please consider subscribing to our (very infrequent) newsletter.

Ease of use

The CPO programs

  • Are easy to use and have a detailed and comprehensive on-line help system
  • Feature a large number of easy-to-use options, such as automatic iteration for focus optimization
  • Tailored to your needs with a 2-dimensional version (CPO2D) for axial or planar symmetry, 3-dimensional version (CPO3D) for all other systems
  • Enable manipulation of electrodes that can be scaled, moved, rotated, stretched, squashed, cropped or copied and repeated
  • Backed by tutorial videos and available as a 64-bit application

Accuracy

The Boundary Element Method

  • No mesh or nodal points, only surface charges on electrodes
  • Many advantages over other methods, including accuracy and speed
  • Large number of benchmark tests to prove high accuracy and reliability
  • Automatic sub-division of electrodes to suit shape
  • Ideal for small electrodes in the presence of much larger electrodes

Space charge

Space-charge and cathodes versions

  • BEM is ideally suited for space-charge and cathodes, since the BEM is charge-based
  • Cathodes of every shape and size can be easily defined
  • Menus for several different cathode emission types, from thermionic to field-emission
  • User-defined emission properties also available
  • Deals with global space-charge spreading and also particle particle stochastic scattering
  • Careful and successful method of damping iterations

Learn the software

Online help and videos

We have made all application help resources available online and have a set of introductory videos available too.

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