Abstract: A laser is a electron device that produces a very narrow, powerful beam of light. The essential components of a laser include an active medium, an energy source, and an optical cavity. The optical cavity itself is enclosed by the resonator which has a mirror at each end. The energy that is put into the laser causes the atoms of the active medium to be excited to a higher energy level. When these atoms relax back down to their ground level they emit photons, which is part of a chain reaction that may cause other atoms to go through the same energy transitions resulting in light that becomes so intense that part of it exits through one of the mirrors as a very strong beam, known as a laser.
The practical uses of lasers are enormous. One of there biggest uses is that they have been used to read and write information on compact discs. Their revolutionary use in the fields of fiber optics communication and medicine are also worth noting.
A laser is a device that produces a very narrow, powerful beam of light. The term laser is an acronym for Light Amplification by Stimulated Emission of Radiation (Hecht 1982). In addition to being intense and narrow, laser beams are coherent, meaning that all of the light waves come out all lined up with one another and are of only one color. In a way a laser can be thought of as a superflashlight.
The ability to focus laser light so precisely makes it extremely powerful. For example, some beams can pierce a diamond, the hardest natural substance known to man, while others can trigger a small nuclear reaction. A laser bean can also be transmitted over long distances with no loss of power. Lasers also vary greatly in size. One is almost as long as a football field, while some are as small as a grain of salt.
Lasers can do a number of incredible things as a result of their special qualities. One area in which they are particularly useful is in recording, storing, and transmitting information. The most common uses of lasers include the recording of music, movies, computer data, and other material on special discs. Bursts of laser light record such material on these discs in patterns of tiny pits (O' Shea). The discs with recorded music and computer data are called compact discs (CD's). A CD allows much more information to be stored on it than a phonograph record, because a laser beam's tight focus, making CDs good for holding data as well as music. The discs are used to storing data are usually called CD-ROM. They are used to store large files of information held in computers that are widely used by businesses, libraries, and government agencies.
Lasers can also read and play back the information on discs. The most well known example of this is the CD player. In a CD player, a laser beam reflects off the pattern of pits as the compact disc spins. Other devices in the player change the reflections into electrical signals and...