Light Emitting Diode

electronic circuit that gives off light at a uniform frequency then an electrical current passes through it

A light-emitting diode (LED) is a semiconductor diode that emits incoherent narrow-spectrum light when electrically biased in the forward direction of the p-n junction. This effect is a form of electroluminescence.An LED is usually a small area source, often with extra optics added to the chip that shapes its radiation pattern. The color of the emitted light depends on the composition and condition of the semiconducting material used, and can be infrared, visible, or near-ultraviolet. An LED can be used as a regular household light source.
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Noun
1. diode such that light emitted at a p-n junction is proportional to the bias current; color depends on the material used
(synonym) LED
(hypernym) diode, semiconductor diode, junction rectifier, crystal rectifier
(part-holonym) digital display, alphanumeric display

LED therapy. Treatment with drugs that become active and may kill cancer cells when exposed to light. LED therapy is type of photodynamic therapy which uses a special type of light to activate the drug.

A semiconductor device that emits incoherent optical radiation when biased in the forward direction. (188 )