A laser diode is a semiconductor device that emits coherent and monochromatic light through the process of stimulated emission. It works by applying a forward bias to a p-n junction, causing electrons and holes to recombine in the active region and produce photons. Unlike conventional light-emitting diodes (LEDs), which produce broad-spectrum, incoherent light, the laser diode generates an intense beam at a single. Compact Size: Laser diodes can be incorporated into small systems and devices due to their small size and lightweight. Threshold Value: It is the most important characteristic of the laser diode.