Ernst Ruska won half the Nobel Prize in Physics in 1986 "for his fundamental work in electron optics, and for the design of the first electron microscope." The other half was jointly won by Gerd Binnig and Heinrich Rohrer "for their design of the scanning tunneling microscope.” " Ernst Ruska, began studying the properties of electron lenses for his Ph.D. Electron lenses are current carrying, coiled wire that produces a magnetic field. Magnetic fields interact with charged particles, and hence can interact with a beam of electrons. He eventually created the electron microscope, which allows magnified images of a specimen by looking at the transmitted electrons of an electron beam through a specimen. These transmitted electrons carry information about the structure of the specimen. They go through electromagnetic lenses that act as a magnifier, and then strike a phosphor material that lights up, creating a visual image that and can be photographed. The magnification exceeds that of an optical microscope. Electron microscopes have resolutions of about 10 million times; optical microscopes are limited to 2000 times.