A TEM works much like a light microscope, however, rather than implementing light waves as a means to illuminate the ultrastructural details of a slide specimen, electrons, which travel at a much lower wavelength, enable the observer to seen these details under a resolution many times greater than when using light. Electromagnets are used as the lenses for this device rather than glass lenses, focusing the beams of electrons through the specimen, which finally hit a fluorescent screen that scintillates when the electrons hit its sensitive surface.