A blue laser is a type of laser that appears to be blue in color. Its light emits a wavelength band of between 360 and 480 nanometers. These blue lasers can have applications ranging from optoelectronic data storage to the medical field.
The blue laser was discovered in Japan by individual researchers and an electronics company. It resulted from years of attempting to develop a blue light-emitting diode (LED). Its successful development can be attributed to the use of gallium nitride crystals rather than zinc selenide, which had been the normal course that previous researchers had taken while trying to develop the blue laser. Though blue lasers technically can provide light at wavelengths between 360 and 480 nanometers, blue lasers generally emit light at 400 nanometers.
Although many people who refer to blue lasers have lasers that are truly blue in mind, blue lasers are closely related to violet lasers as well. In fact, a popular "blue" laser that operates at 405 nanometers is actually violet. The public can confuse this violet laser with a blue laser because the two types look very similar to the human eye. When looking at a 405 nanometer light, people can mistake the florescence for a blue color; as a point of reference, black lights also can trick the human eye in the same way. It could be said that people are looking at true blue light colors only when they are viewing a light with a wavelength of between 450 and 460 nanometers.
The practical applications for blue lasers are many. The telecommunications, information technology, environmental monitoring, medical diagnostics and electronic equipment industries all have benefited from blue light lasers. Micro projectors and displays can use blue lasers for operational purposes.
Blue lasers also have changed the way consumers experience entertainment. A blue laser makes high density (HD) digital versatile disc (DVD) data storage and Blu-ray™ technology possible. Its shorter wavelength than other types of lasers is what provides this capability, because lasers of shorter wavelengths can read increased concentrations of information off the discs.
Standard laser pointers also come with a blue laser option. These blue lasers can operate with a 473 nanometer wavelength. For those who tire of the red and green laser alternatives, a blue laser can provide a bit of uniqueness to laser use. However, because they use a newer technology, blue lasers might be a more expensive choice.