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. They are exceptionally accurate and easy to use, and have been described as the gold standard of charged particle optics.

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Introducing the CPO Consultant Programme

Independent specialists who know CPO, available for initial consultations and longer engagements.

Every new CPO3D, CPO3DS or Complete licence includes an initial consultation with an independent specialist who uses the software in their own work. You choose the consultant, we make the introduction, and we pay for the session.

If you use CPO at an expert level, the network is open to you. We arrange and pay for the initial consultation, and whatever you agree with the customer afterwards is yours.

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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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