The active region of the laser diode is in the intrinsic (I) region, and the carriers (electrons and holes) are pumped into that region from the N and P regions respectively. In 1992, Japanese inventor Shuji Nakamura, while working at Nichia Chemicals, invented the first blue semiconductor LED using an InGaN active region, GaN optical guide and AlGaN cladding, and four years later, the first low-power blue laser; eventually receiving the Millennium. A laser diode (LD, also injection laser diode or ILD or semiconductor laser or diode laser) is a semiconductor device similar to a light-emitting diode in which a diode pumped directly with electrical current can create lasing conditions at the diode's junction. A blue laser emits electromagnetic radiation with a wavelength between 400 and 500 nanometers, which the human eye sees in the visible spectrum as blue or violet. Blue lasers can be produced by: Lasers emitting wavelengths below 445 nm appear violet, but are nonetheless also called blue lasers. Summary: Cd-Doped InGaN 149 149 150 150 151 151 154 155 155 155 155 159 160 160 161 161 166 XIV 9. Zn and Si Co-Doped InGaN/AlGaN Double-Heterostructure Blue and Blue-Green LEDs 10.
Read More
