The paper outlines fundamental issues of electron microscopy and models three selected shapes of the differential chamber using the SolidWorks system. The models are then analysed using Cosmos FloWorks with regard to vacuum pumping. The aim is to find a model with minimum pressure in the electron beam trajectory and hence the least dissipation.

The paper briefly outlines high-pressure electron microscopy and then uses SolidWorks to model the scintillation detector, analysing pumping of gas in the EREM sample chamber at different pressure levels using Cosmos FloWorks. The results of the analysis are assessed with regard to minimising pressure in the trajectory of the primary electron beam in order to prevent dissipation of electrons on the gas molecules.