iconductor lasers, gas lasers, and dye lasers. In 1960, the American physicist Theodore H. Maiman built the first laser. At first, lasers had few uses, and scientists often thought of them as "a solution looking for a problem." Today, however, lasers rank among the most versatile and important tools in modern life. How lasers are used Lasers can do a number of incredible things. Their special qualities make them particularly useful in recording, storing, and transmitting many kinds of information. Lasers also are valuable in such activities as scanning, heating, measuring, and guiding. As a result of their wide use, lasers can be found in equipment used in homes, factories, offices, hospitals, and libraries. Recording, storing, and transmitting information. The most common uses of lasers include the recording of music, motion pictures, computer data, and other material on special discs. Bursts of laser light record such material on the discs in patterns of tiny pits. The discs with recorded music and computer data are called compact discs (CD's). A laser beam's tight focus allows much more information to be stored on a CD than on a phonograph record, making CD's good for holding data as well as music. Some CD's even can hold an entire encyclopedia. A disc used for storing data is usually called a CD-ROM (Compact Disc Read-Only Memory). Such discs store databases (large files of information held in computers) and are used widely by businesses, libraries, and government agencies. Lasers can also read and play back the information recorded on discs. 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 decode them as music. More lasers are used in CD players than in any other product....
