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The 24 pages that link to Electron microscope, each with the reason it gives.
ElectronBroader topic: Electrons can reveal structures finer than visible-light microscopes resolve.
VacuumRelated: A vacuum lets electrons travel without substantial scattering by gas molecules.
MicroscopeBroader topic: Electrons replace visible light to reveal much finer specimen details.
Electron gunRelated: Its illumination system uses an electron gun to create the probe beam.
Vacuum pumpRelated: Its vacuum limits collisions between beam electrons and gas molecules.
VirologyRelated: Electron microscopy made direct visualization of virus particles possible.