atomic force microscope

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun A microscope, capable of a magnification factor of 5 × 10⁶ and a resolution of 2 angstroms, that provides a map of the atoms on the surface of an object by measuring the attractive and repulsive forces arising between a tiny probe drawn along the surface and the atoms on that surface.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun physics A device used to map the atomic structure of a surface by measuring the force acting on the very fine tip of a wire moved over the surface