Even though electrons are seen to behave like wave, still, how would something “see” the electrons?
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An electron microscope doesn’t “see” electrons. It uses a beam of electrons to create an image of things.
In a Scanning Electron Microscope (SEM), a very tight beam of electrons is scanned across a small area of the sample to be imaged. Some of the electrons are reflected, and some of them stimulate the sample to emit other electrons.
These electrons are attracted to a positively charged detector. The detector includes a “scintillator” which absorbs electrons and emits light, much like the phosphors on an old CRT TV. The light is amplified and used to modulate the current through a circuit. That circuit is used to create the image on the SEM screen.
To summarize, the electron beam leads to electrons coming off the sample, which are turned into light, which is then turned back into electron flow (current), which is turned into an image on a screen (light).
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