Lasers 50 years old today! sort of....

Anyone who scans a tin of beans at the checkout is using a laser. Anyone who listens to music on a CD is using a laser to read data stored on a disc. Anyone who sends an e-mail is reliant on the lasers that drive the world's fibre optic communications networks. Anyone who gets into a car is sitting in a box that owes its construction to lasers.


(1) A powerful lamp is wrapped around a ruby rod, depositing energy in the form of undirected light of many colours, or wavelengths
(2) Atoms in the rod absorb and store energy from the light
(3) Reflecting mirrors then allow a small amount of light to bounce back and forth in the rod, collecting some of the atoms' stored energy on each pass
(4) Some of the light escapes through one of the mirrors; it is a directed, intense beam of synchronised light waves of a specific colour


"There is a phenomenal amount of laser processing on a car; you wouldn't believe how much - laser cutting, marking, measurement, drilling, hardening, laser brazing, laser deposition, and laser welding," explained Tim Holt, the chief executive of the Institute of Photonics, University of Strathclyde.

"Modern cars today would not be possible without lasers."


The worldwide market in lasers is worth some $5-7bn annually. Most of that value is in lasers sold to manufacturing outlets for use in material processing, but the two other key markets are lasers for use in communications systems and in data storage.

BBC