Electron Optics Instruments — The Science Behind SEMs

Born in the 1920s, electron optics is a branch of physics concerned with electron trajectories. During the early stages of electron optics, it was stated that wavelengths should be associated with moving particles. 


Not many years later, it was demonstrated that the movement of these electrons could be translated into the language of geometrical optics. This science is based on the property of electrons, which can be treated either as a wave or as a particle.

The Most Common Application is Electron Microscopy

Although electron optics is a branch of physics and has many applications, electron microscopy is probably the most relevant to our lives. These impressive microscopes can magnify samples up to a million times (x1,000,000) thanks to the mathematical framework used for the calculation of electron trajectories.


Each microscope, regardless of its type, is state-of-the-art equipment that combines decades of investigation and knowledge with complex technology and software.


Using beams of electrons focused by electric and magnetic fields, electron microscopes can detect their deflection, their interference, and their diffraction or bending to create impressive images of submicroscopic structures. In fact, thanks to this technology we can see atoms.

Electron Optics in Scanning Electron Microscopes

Understanding the behavior of electrons and their interaction with matter and magnetic fields is essential for SEMs to work. 


To give an idea of how precise and powerful an electron microscope is, the electron beam fired by these microscopes typically has an energy ranging from 0.2 keV to 40 keV. The beam can be focused by condenser lenses to 0.4 nm in diameter before passing through scanning coils or deflector plates.


Once the electrons interact with the sample, x-rays, backscattered electrons, and secondary electrons are produced. The detectors in the sample chamber are then able to create very detailed images using the signals created.


The digital images created at the nanoscale are extremely detailed and provide researchers with information that can’t be obtained otherwise. Shape, texture, and even element composition and arrangement of the atoms in any given material.

All Of This Is Just Possible Thanks To Electron Optics

While electron microscopes are not as popular as other inventions, and electron optics is not as widely known as other branches of physics, their direct and indirect impact on our lives is simply undeniable.


Electron Optics Instruments sets a new standard in scanning electron microscopy. Offering the best Traditional and Tabletop SEMs on the market, our SEMs are focused on image quality and ease of use. From tabletop SEMs that can be installed just like a personal workstation, to SEMs optimized for productivity.


Contact a member of the EOI team for full specifications, recommended applications, or a quote.