The Laser Essay -- essays research papers

The LaserBefore we can learn about the laser we need to know a little bit aboutlight (since that is what a laser is made of). Light from our sun, or from anelectric bulb, is c alled white light. It is really a mixing of all thedifferent colours of light. The colours range from violet, indigo, and blue, togreen, yellow, orange, and red. These make up the visible part of theelectromagnetic spectrum. Light is made up of particles, called PHOTONS, whichtravel in waves. The difference in the colour depends on the wavelength of thelight. Violet light has the shortest wavelength while red has the longest. Thereare other parts of the electromagnetic spectrum which includes infra-red, radar,television piano tuner and micro- waves (past red on the spectrum), and on the otherend of the spectrum are the other invisible radiations, ultra- violet, X rays,micro waves and gamma rays. The wavelength of the light is important to thesubject of the laser. A laser is made up of COHERENT light, a spec ial kind oflight in which the wavelengths of the light are all the same length, and thecrests of these waves are all lined up, or in PHASE. The word Laser is anacronym for Light Amplification by Stimulated Emission of Radiation. What doesthat mean? Basically a laser is a device which produces and then amplifies lightwaves and concentrates them into an intense penetrating beam.The principles of the laser (and its cousin the maser) were establishedlong before these devices were succes...