This coherent light is produced by the laser diode using a process termed as “Light Amplification by Stimulated Emission of Radiation”, which is abbreviated as LASER. And since a p-n junction is used to produce laser light, this device is named as a laser diode. 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. The intrinsic layer is sandwiched between the P-type and N-type layer. Metal plates are connected with p-layer and n-layer to form the terminals anode (+) and cathode (-) respectively.
[pdf] Laser diodes are semiconductor lasers with a current-carrying p–n junction as the gain medium. They are the most important type of electrically pumped lasers. In such a heterostructure of a bipolar interband laser, electrons and holes can recombine, releasing the energy. Laser diodes (LD) are semiconductor devices that convert electrical energy into high-power optical energy.
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