>>11391130They rely on semiconductor crystals as a lasing medium and are actually light oscillators, not amplifiers. They take current and convert it into collimated visible light. In the past couple of years, high powered directly injected green diodes have become a reality. Beforehand, green wavelengths were only created by pumping certain semiconductor crystals with an IR laser. The direct green diodes are a bit more stable as they are multimode and do not produce any IR radiation.
High powered blue diodes are cheap as fuck now and you can easily build 7+ watt monsters using the Nichia NUB44 diode. I personally don't think I would make one though, I just made a 2.2W using an Osram PLTB450B diode and it's already ridiculously scary.
