Optical Lasers

5 Pages 1344 Words

I am doing my report on lasers. Laser, acronym for light

amplification by stimulated emission of radiation. Lasers are

devices that amplify light and produce coherent light beams,

ranging from infrared to ultraviolet. A light beam is coherent

when its waves, or photons, propagate in step with one

another. Laser light, therefore, can be made extremely intense,

highly directional, and very pure in color. Laser devices now

extend into the X-ray frequency range.

This is the Principles of Operation. Lasers bind atoms to

store and give out light in a coherent fashion. The electrons in

the atoms of a laser medium are first pumped to an excited

state by an energy source. They are then stimulated by external

photons to emit the stored energy in the form of photons, a

process known as stimulated emission. The photons emitted

have a frequency characteristic of the atoms and travel in step

with the stimulating photons. These photons in turn impinge, or

invade on other excited atoms to release more photons. Light

amplification is achieved as the photons move back and forth

between two parallel mirrors, triggering further stimulated

emissions. The intense, directional, and monochromatic laser

light finally leaves through one of the mirrors, which is only

partially silvered.

Several people have discovered lasers over the years.

Albert Einstein was the first scientist to propose stimulated

emission, the underlying process for laser action, in 1917. Here

are some more people who have created or developed ideas for

lasers. The American physicists Arthur Leonard Schawlow and

Charles Hard Townes in their 1958 patent application outlined

the working principles of lasers. The patent was granted, but

the American physicist and engineer Gordon Gould later

challenged it. In 1960 the American physicist Theodore Maiman

observed the first laser...