Laser diodes based on new group of semiconductors (gallium nitride) are able to emit the light in the UV and visible range. As for present, lasing was achieved by various groups and companies in the range from 370 up to 530 nm.
Roughly speaking, nitrides laser diodes can be classified into six groups:
1. UV-LDs operating in the range from 370 up to 400 nm,
2. Violet LDs operating at the range of 400-420 nm. Here the specially important wavelength is 405 nm, know from DVD standard – BluRay,
3. Blue-violet range 420 – 440 nm,
4. True blue range 440 – 450 nm. This wavelength is usually the wavelength of choice for a blue component of laser projectors,
5. Blue green range 488 – 500 nm. This region is interesting (between the others) a replacement of argon ion lasers,
6. Green region 500 – 530 nm. These devices play a crucial role in the laser diode displays (green component).
Application of nitride lasers:
UV laser diodes: chemical detection, biological and chemical spectroscopy, photolithography, ink curing, photochemistry
Violet laser diode: optical data storage (DVD), fast printing, silicon thermal processing
Violet-blue laser diode: spectroscopy, laser traps, atomic clocks
Blue laser diodes: displays from pico-projectors to movie theater projectors
Blue-green laser diodes: plastic fibers telecommunication, underwater communication
Green laser diodes: displays from pico-projectors to movie theater projectors