求一篇关于激光方面的3000字左右的英文文章

What is a Laser?

Most people know the word laser, but do they know what it really is? What's the difference between ordinary light and laser and what does laser really stand for? Let's start with the last question. Laser is an acronym, that is a word made up of initial letters. You could use the complete name: light amplification by stimulated emission of radiation but that's a bit awkward, let's keep to laser.

Almost everyone probably knows that the police use laser when they measure speed. At least many drivers that have exceeded the speed limit know about it, but how many know that you also use laser several times during an ordinary day? You'll find it in CD players, laser printers and much, much more.

You often find laser in action movies where the hero has to escape the laser beams when he's trying to solve a thrilling problem. The power contained in laser is both fascinating and frightening.

How Does Laser