light emitting diode abbr., LED (rus. светодиод) — semiconductor source of incoherent optical radiation, whose principal of operation based on the electroluminescence phenomenon.

Description

LED optical radiation emerges in the process of electron-hole recombination within the active region. The emitted light lies in the narrow spectral range, its colour characteristics dependent on the LED semiconductor bandgap. Like any semiconductor diodes, LEDs have p-n or metal-semiconductor junctions.

When electric current flows in the forward direction, the charge carriers – electrons and holes – recombine and emit photons. Good emission characteristics are generally demonstrated by LEDs based on direct-gap semiconductors.

Author

  • Dmitry R. Khokhlov

Source

  1. Light emitting diode // Wikipedia, the free Encyclopedia. — http://en.wikipedia.org/wiki/Light-emitting_diode (reference date: 31.07.2010).