Laser is an acronym for "Light Amplification by Stimulated Emission of Radiation," which doesn't make things nearly as clear as if it were "Let's All Start Eating Rabbits," probably bad advice, particularly from the rabbit's point of view, or "Lonnie Anderson Still Earns Royalties," which is a sad comment on television but brings us no closer to understanding lasers. It could be worse. If you had to explain this to a classroom full of adolescents, they'd still be giggling about Stimulated Emission, so you wouldn't get far even if you did know how they worked.
Apparently, during the brief instant that an atom is excited (by who-knows-what) and light of a certain wavelength impinges on it, the atom can be stimulated to emit radiation that is in phase with the wave that stimulated it. I know some teen-age boys in the back row are imagining penises right now, but remember that James Bond movie where Blofeld tried to use a laser to cut off James Bond's penis? Imagine that. Right now. While you're in a period of burgeoning maturity and still lack sexual confidence. Then imagine Jack Klugman naked. I'll bet you're not so giggly now.
Albert Einstein understood stimulated emission as early as 1917—or so he claims now, or would if he weren't dead—but it was not until the 1950s that practical applications were found for this technology. Impractical applications would have to wait a few decades more when years of scientific ingenuity resulted in laser tag, laser pointers, and cool holograms on the sides of cereal boxes.
Lasers can also be used as measuring devices, as cutting tools—both in industrial applications and in medical and dental procedures—as a form of radar, in communications devices, for recording and storing data, and in computer printers. President Reagan thought lasers could be used to make a cool death ray, but he may have been thinking of some movie, perhaps featuring James Bond's penis. Can you blame him?
Stimulated Emission Answer
U.S. officials fear that Iran will use the lasers to make fuel for nuclear weapons.
Administration officials have been trying for three months to stop the sale. "I cannot conceive of this type of equipment being used for any other purpose than the one we are concerned about," said one nuclear expert. "Except perhaps for cutting off James Bond's penis," he did not add.
Lisa de Moraes writeth in the Washington Post: "I want an on-air job at ABC News. Did you know they pay you more to work less there?"