Musica edin torni

For the fictional organization, see Cheat Commandos. A blue laser is a blue beam does not open pdf that emits electromagnetic radiation with a...

For the fictional organization, see Cheat Commandos. A blue laser is a blue beam does not open pdf that emits electromagnetic radiation with a wavelength between 360 and 480 nanometres, which the human eye sees as blue or violet. Blue beams are produced by helium-cadmium gas lasers at 441.


6 nm, and argon-ion lasers at 458 and 488 nm. Both blue and violet lasers can also be constructed using frequency-doubling of infrared laser wavelengths from diode lasers or diode-pumped solid-state lasers.

Diode lasers which emit light at 445 nm are becoming popular as handheld lasers. Light of a shorter wavelength than 400 nm is classified as ultraviolet.

Devices that employ blue laser light have applications in many areas ranging from optoelectronic data storage at high density to medical applications. Using methods similar to those developed for silicon, the substrate can be built free of the defects called dislocations, and the atoms laid down so the distance between the ones making up the ground and those of the quantum wells are the same. The technical problems seemed insurmountable, so researchers since the 1960s have sought to deposit GaN on a base of readily available sapphire. But a mismatch between the structures of sapphire and gallium nitride created too many defects.

In 1992 Japanese inventor Shuji Nakamura invented the first efficient blue LED, and four years later, the first blue laser. Sylwester Porowski developed technology to create gallium nitride crystals with high structural quality and fewer than 100 defects per square centimeter — at least 10,000 times better than the best sapphire-supported crystal. In 1999, Nakamura tried Polish crystals, producing lasers with twice the yield and ten times the lifetime — 3,000 hours at 30 mW. A further development of the technology has led to mass production of the device.

After 10 years, Japanese manufacturers mastered the production of a blue laser with 60 mW of power, making them applicable for devices that read a dense high-speed stream of data from Blu-ray, BD-R, and BD-RE. Polish technology is cheaper than Japanese but has a smaller share of the market.

Ammono, but this company does not produce blue lasers. For his work, Nakamura received the Millennium Technology Prize awarded in 2006, and a Nobel Prize for Physics awarded in 2014. Until the late 1990s, when blue semiconductor lasers were developed, blue lasers were large and expensive gas laser instruments which relied on population inversion in rare gas mixtures and needed high currents and strong cooling.

admin