A Technical History of the Laser

Lasers are often thought of as either toys or science fiction, but the laser is actually a very important tool for scientists, and increasingly important in everyday life and industry. This history from the theoretical foundations created in 1917 to its common use in modern days is one that most people do not know and is quite interesting.

In 1917, Albert Einstein envisioned the idea of stimulated emission which, theoretically, allows scientists to cause light to be emitted in a single frequency rather than in the range of frequencies which make up natural light¹. In his theory he suggested a chain reaction could trigger a sudden release of photons. This eventually gained the acronym LASER which stands for light amplification by stimulated emissions of radiation.

In 1954 papers discussing MASERs were published. These use the same concept of stimulated emissions but microwaves.  Ten years later in 1964 these men who published these papers won the noble prize for their contributions.  These have been discovered naturally in space, and man made masers are often used for the same things as lasers.

It was forty-three years on may 16th 1960 that the first laser was operated at the Hughes Research Laboratory². The process for this laser had researchers shining a high powered flash lamp on a silver coated ruby rod.  The first public announcement occurred in July.  By 1962 a laser with visible light emissions were available and by 1970 lasers were created which could be used at room temperature  and continually operated making them far more useful.

In the forty years since, lasers have been optimized in a wide variety of ways. The number of wavelengths which can be used have increased, the average output power has increased, power efficiency has improved and cost has dropped dramatically. This has led to hundreds of different uses for the laser.

When first used in 1960 lasers were called a solution looking for a problem. The first common use of this technology was the bar code scanner. Shortly after the laser disc player was used and laser printers in 1982. It is now nearly impossible to find a computer that does have a computer in it at some point.

Today lasers are used in almost every industry. Medicine uses lasers in bloodless surgery, to remove kidney stones, fixing eyes and even dentistry. They are used industrially to cut and wield and to make parts.  The military uses them for missile defense and guiding munitions and even the cosmetic industry now uses lasers.

In the future the growth of their value is only going to increase.  Nanotechnology uses them to build machines smaller than the eye can see, creating true three dimensional images, allow computers to work at the speed of light, create virtually unlimited energy supplies and things that no one has even thought of yet³.

1- http://www.usatoday.com/tech/science/2010-05-14-1Adeathray14_VA_N.htm

2- http://www.press.uchicago.edu/Misc/Chicago/284158_townes.html

3- http://www.scienceclarified.com/scitech/Lasers/The-Future-of-the-Laser.html