Industry

Powerful laser beams can be focused on a small spot with enormous power density. Consequently, the focused beams can readily heat, melt or vaporize material in a precise manner. Lasers have been used, for example, to drill holes in diamonds, to shape machine tools, to trim microelectronic components, to heat-treat semiconductor chips, to cut fashion patterns, to synthesize new material, and to attempt to induce controlled nuclear fusion. The powerful short pulse produced by a laser also makes possible high-speed photography with an exposure time of several trillionths of a second. Highly directional laser beams are used for alignment in road and building construction.

Lasers are used for monitoring crustal movements and for geodetic surveys. They are also the most effective detectors of certain types of air pollution. In addition, lasers have been used for precise determination of the earth-moon distance and in tests of relativity. Very fast laser-activated switches are being developed for use in particle accelerators, and techniques have been found for using laser beams to trap small numbers of atoms in a vacuum for extremely precise studies of their spectra.