阅读下面短文.然后完成表格. Laseris a device that strengthens light．A laser produces a thin b

阅读下面短文，然后完成表格。

Laser（激光）is a device that strengthens light．A laser produces a thin beam of light that can burn a hole in a diamond or carry the signals of many different television pictures at the same time．The word laser stands for light amplification by stimulated emission of radiation．The light from a laser is different from the light of the sun or the light produced by ordinary electric bulbs． These sources send out their light in all directions．Unlike ordinary light sources，a laser sends out a narrow beam of light in only one direction．The sides of the beam stay parallel（平行的）．Also，a laser produces light that has a narrow frequency range

and so the light contains only a single color．Lasers can perform a wide variety of jobs because of the unusual properties of laser light．Scientists continue to look for new uses as they develop new kinds of lasers．

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