Even though electrons are seen to behave like wave, still, how would something “see” the electrons?
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When light strikes a detector in a camera, it trips something in that detector, for instance it moves an electron. This moved electron creates an electronic signal which we use to recreate the image.
There are many ways to detect electrons. One option it actually to ‘cheat’ and use the electron to create light. Then you detect it with a very sensitive light sensor.
Electron microscopes tend to be a little bit different than your standard camera, as lensing electrons to project an image can become impractical. Instead, they take other approaches. A scanning electron microscope, for instance, fires a beam of electrons and generates the image “one pixel at a time” as the beam slowly crawls across the subject.
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).
You don’t. TEM and SEM are used to view very small specimens, the general procedure varies depending on what you’re looking for, for example in cell biology, certain proteins of interest are looked at using gold attached to antibodies, the gold balls reflect the beam of electrons creating very dark regions, which can be seen in imaging. Electrons themselves however, cannot really every be seen, we can only predict roughly where they are, which represent solutions to the Schrödinger equation.
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