Word: lasered
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Dates: during 1970-1979
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...took many decades of research and three basic developments to make communication by optical wires a reality. One development was the invention in 1960 of the laser, a device capable of generating an intense narrow beam of light that, for all practical purposes, did not diverge. Miniaturized lasers make it possible to couple powerful light beams accurately with hair-fine glass fibers. Another was the perfection, by Corning Glass Works, of a fiber of glass so pure that it could transmit light long distances. The third accomplishment was the devising, by engineers at Bell Labs and elsewhere, of methods...
...travel along a copper wire to another phone, where they are converted back to sound waves. In a typical optical arrangement (see diagram), sound waves entering a telephone microphone are converted into electrical signals. These signals pass through an encoder, which converts them into electrical pulses that switch a laser on and off, interrupting a light beam being sent into the end of a fiber. The light thus travels in a series of pulses, not unlike Morse code, that race along the glass "wire." At the end of their journey, these light pulses are picked up by a photodetector, which...
...appalled to read in the article on lasers [Jan. 12] that in addition to repairing retinal detachments as a medical usage, lasers were also used to remove cataracts. I have spent a number of hours over the past several years explaining to patients that lasers are not used in the removal of cataracts. In fact, the presence of a cataract many times precludes using the laser in treatment of diseases of the back of the eye, since the laser beam will not penetrate a dense cataract...
...laser (the word is an acronym for light amplification by stimulated emission of radiation) has been around since 1960, when scientists first succeeded in producing the powerful beams of single-frequency light waves. These beams could be delivered to distant points with much less diffusion and loss of intensity than ordinary beams, which consist of the helter-skelter waves of white light. In recent years, using light generated by gases or chemical reactions, researchers have greatly increased both the power and range of lasers...
...researchers are seriously considering lasers as antipersonnel weapons; there are easier and cheaper ways to kill individual enemy soldiers. But more effective laser applications are under intensive investigation. Most laser research is highly classified, but Army authorities are known to be testing a tank-mounted high-energy laser...