Lasers that lie in the green spectral region with a wavelength of 510 to 570 nanometers are termed as green lasers. Green laser technology is used in laser pointers, laser projection displays, interferometers, and for pumping of solid-state lasers such as Ti-sapphire lasers. It is also used in processing different types of materials such as copper, gold, or silicon as they have a much higher absorption coefficient as compared to near-infrared lasers.
Green laser usage and performance is limited, as it has a low spectrum range for selecting a laser gain media. However, they are the most commonly used visible lasers due to their uniqueness.
The most common lasers include Argon-ion lasers that are created with the amplification of light in argon plasma formed with an electrical discharge. They are potent light sources for various wavelengths and can achieve highest amount of power at 514 nanometers. Green lasers can easily exceed these limits, but will have to use many kilowatts of electrical power and the corresponding increase in dimensions of cooling systems will be significant. Small air-cooled tubes are used in green lasers that require hundreds of watts of electrical power for generating green laser beams of 10 mille-watts capacity. The tubes are very expensive and have a limited operational life of around a few thousand hours.
Another type of green laser is the Erbium-doped up-conversion laser based on erbium-doped fibers or bulk crystals that can emit around a 550-nanometer good quality laser beam. Frequency-doubled is another technique of creating green laser, in which a frequency doubler is used to convert radiation emitted by a normal laser into green laser. This technique is however very costly and is used only for conducting research work.
Research scientists are working on a number of projects for developing a mechanism that will enable the transmission of electronic data via green lasers. This mechanism, if successfully developed at affordable costs, will change the way people communicate with each other.