Working principle of laser diode LD

The working principle of a laser diode is based on stimulated emission and population inversion within a forward-biased semiconductor p-n junction. When sufficient current flows, more electrons occupy the excited state than the ground state (population inversion). 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. It works on the same basic principle as an LED, but with an internal structure that forces photons to align in phase and direction, producing coherent laser light instead of the. A laser diode is a small semiconductor device that emits powerful and precise light using a process known as stimulated emission. Laser Diode has the same working principle as LEDs.