Making his own scanning electron microscope? It's easy for Ben Krasnow, who has already built a liquid nitrogen generator and a transcranial magnetic stimulation system.
For his latest achievement, he explains: "I wanted to see if it was possible!" And it was!
So the University of California, Santa-Barbara graduate began studying the complex and delicate physics involved in such an instrument. He then scoured eBay for low-cost components, and built himself what he couldn't find.
One of the difficult tasks in this construction was to produce an electron gun. To do this, he used a thin tungsten wire which he heated by applying a very high voltage, producing a cloud of electrons. To focus this cloud into a precise net, the released electrons then pass through a tiny copper tube before reaching their target.
The microscope provides a 3D view of the surface of objects with a 50x zoom, displayed on a conventional oscilloscope.
Source : Presse-citron
Learn more: benkrasnow.blogspot.com/2011/03/diy-scanning-electron-microscope.html