# I'm trying to understand how an electron microscope works

I know an electron microscope can collect x-rays emitted by electron holes, backscattered electrons as well as secondary electrons. I get that an electron's wavelength is much smaller than a photons, thus you get finer image resolution, but how exactly does a shorter wavelength mean a finer resolution? I know the photon's longer wavelength causes it to "overlook" finer details, but how exactly does a wave "overlook" something?

How does a wavelength interact with a physical surface to cause this? I could see this making more sense if i treat a wave as a particle oscillating in space and, when fired down vertically, hits a steep surface horizontally and reflects off into a detector... but I dont think that's what really happens. And if you treat an electron as a wave, how do you end up with backscattered electrons?

I guess what im really saying is I dont know how to bridge the gap between the electron's wave-like nature and its physical counterpart.

Drakkith
Staff Emeritus
How does a wavelength interact with a physical surface to cause this? I could see this making more sense if i treat a wave as a particle oscillating in space and, when fired down vertically, hits a steep surface horizontally and reflects off into a detector... but I dont think that's what really happens. And if you treat an electron as a wave, how do you end up with backscattered electrons?

The effect is similar to how a low pitch sound will travel around objects better than a high pitch one will. However a particle isn't just a simple wave, it is a wave packet. In a manner similar to how a sound wave can bounce off an object, particles can bounce off objects they cannot pass through as well.

Ah, so a single electron particle is a gaussian wave packet... which is an amalgamation of many waves put together, which constitutes a particle. And an electron's matter wave properties come out when it's forced into a slit smaller than the size of it's wave packet?

Drakkith
Staff Emeritus