A laser beam is a stream of focused, coherent light in a single wavelength. Although the word laser generally is accepted in common language, it originally was an acronym for "light amplification by stimulated emission of radiation." There are many different kinds of lasers that are used in a wide range of technological applications, including welding and surgery. Lasers also play a role in science fiction where they are typically depicted as powerful weapons.
When an atom is exposed to energy, the orbits of electrons within the atom can change. As this happens, particles of light called photons are released. In a normal beam of light, the photons are released in a random way; in a laser beam, the photons are concentrated and more organized. This is generally achieved through a process called stimulated emission, which happens when photons released by one atom stimulate other atoms to generate photons with the same wavelength. Most laser devices also contain mirrors that allow a light beam to bounce repeatedly, thereby slowly building a large chain reaction until a laser beam is created.
The first reported laser was developed in 1960 by Theodore Maiman who used the combination of a high powered light and a ruby rod coated in silver. His discovery was initially ignored because it seemed too similar to earlier experiments involving focused light. It took a while for scientists to realize the significance of Maiman’s discovery, and it took even longer to find uses for the technology.
Gordon Gould also has a claim for being the inventor of the laser, and there is some dispute about which man deserves the most credit. Gould claims he developed a functioning laser in the late 1950s, but he took too long to file for a patent. Whether or not Gould can be given credit for developing the first actual laser beam, he is generally acknowledged as the first man to use the term laser.
In the early days, laser beams were mostly used as a replacement for other concentrated light technologies that were available at the time. Scientists quickly developed some ideas for laser applications but it took some time to iron out certain technical difficulties. Over time, lasers worked their way into many devices that the average person may encounter on a daily basis. Some common applications of laser technology include barcode readers, DVD disc drives, and security systems. The Laser beam has also made an impact in the world of medicine by allowing doctors to perform delicate surgeries that would not be possible without the fine control and accuracy that lasers provide.