Blue laser
From Wikipedia, the free encyclopedia
- For other uses of the term, see Blue laser (disambiguation).
Blue lasers have applications in many areas, from opto-electronic data storage at high-density, to medical applications. Until the mid 1990s blue lasers were large and expensive gas laser instruments which rely on population inversion in rare gas mixtures and need high currents and strong cooling. In the mid 1990's Shuji Nakamura at Nichia Chemical Industries in Anan (Tokushima-ken, Japan), in a series of inventions, developed commercially viable blue and violet semiconductor lasers based on gallium nitride compound sectors, using quantum wells or quantum dots spontaneously formed via self-assembly. This invention enables the development of small, convenient and low priced blue, violet and UV lasers, which have not been available before, opening the way for applications such as high-density HD DVD data storage and Blu-ray disc. The shorter wavelength will allow it to read discs with much more information.
Blue laser light usually has a relatively low input-to-power efficiency. Blue lasers usually operate at around 472 nm.
Use of indium gallium nitride as a semiconductor material suitable for formation of quantum heterostructures is proposed. Recently, CdS/ZnS quantum dots have been used as the gain material in spherical Whispering Gallery Mode lasers; see Applied Physics Letters, 2005, 86:073102.
[edit] See also
[edit] Further reading
- Shuji Nakamura, Gerhard Fasol, Stephen J. Pearton, The Blue Laser Diode : The Complete Story, Springer; 2nd edition, October 2, 2000, (ISBN 3-540-66505-6)
