Lasers

摘要

1 Chances are, you can thank a laser for helping you get through the day. The technology lets us do everything from scan groceries at the checkout to remove regretted tattoos. 2 The word laser, coined in 1957, is an acronym for "light amplification by stimulated emission of radiation." Since that -er ending makes a laser seem like a doer of ... something, it soon spawned the verb "to lase." 3 Unlike the sun or a flashlight, which shines in a broad range of colors combined to produce white light, lasers lase by producing a concentrated beam of a single wavelength, or color. 4 In 2016, scientists created a new type of microlaser, smaller than a red blood cell, which could lead to innovations in medical imaging.