Lasers :: essays research papers

The laser is a device that produces a communicate of fall. The burn is produced by a process known as stimulated emission, and the member &8220laser is an acronym for the phrase &8220 short amplification by stimulated emission of radiation. lasers inflate light and produce coherent light beams. A light beam is coherent when its waves or photons ar in step with one another. Laser light can be made extremely intense, highly directional, and very pure in color.BASIC PRINCIPLES blowsy can be characterized both by its frequency, or number of wave crests passing a abandoned point per second, and by its wavelength. Different wavelengths of light be seen as assorted colors. Like radio waves, light can also carry information. The information in the beam varies in the frequency or shape of the light wave. Because light waves are of much higherfrequencies than radio waves, the have a higher information carrying capacity. In beams of light,individual photon waves are not moving on to gether because they are not being emitted at the same present moment but instead in random short bursts. Such beams are called incoherent.The process for laser action, was first proposed by Albert Einstein in 1917. The running(a) principles of lasers were outlined by the American physicists Arthur Leonard Schawlow and Charles Hard Townes in their 1958 overt application. The patent was granted but was later challenged by the American physicist and engineer Gordon Gould. In 1960 the American physicist Theodore Maiman observed the first laser action in fast(a) ruby.HOW A LASER WORKSA laser is made up of several basic components. One is called active voice medium, which consists of atoms of a gas, molecules in a liquid, ions in a crystal, or any of several other possibilities. another(prenominal) component consists of many method of introducing energy into the active medium, such as a fritter lamp. The third basic component is a cope with of mirrors placed on eitherside of the ac tive meduim, one of which transmits break up of the radiation that strikes it. Atoms initially in a lower state are raised to the upper state by energy from a flash lamp or some other pumping source. Some of these atoms emit light in random directions. Light traveling vertical to the mirrors stays within the active medium long enough to stimulate emission from otheratoms. Light traveling in other directions are soon lost. Some light reaching the output mirror is transmitted to form the laser beam, some is reflected back through the medium to continue the stimulated-emission process.