a rectifying semiconductor device which converts electrical energy into electromagnetic radiation of a wavelength in or near the visible spectrum of light
To emit a sound or noise means to produce it. Polly blinked and emitted a long, low whistle. to send out gas, heat, light, sound etc (emittere, from mittere )
To send forth; to throw or give out; to cause to issue; to give vent to; to eject; to discharge; as, fire emits heat and smoke; boiling water emits steam; the sun emits light
If something emits heat, light, gas, or a smell, it produces it and sends it out by means of a physical or chemical process. The new device emits a powerful circular column of light
Semiconductor diode that produces visible or infrared light when subjected to an electric current, as a result of electroluminescence. Visible-light LEDs are used in many electronic devices as indicator lamps (e.g., an on/off indicator) and, when arranged in a matrix, to spell out letters or numbers on alphanumeric displays. Infrared LEDs are used in optoelectronics (e.g., in auto-focus cameras and television remote controls) and as light sources in some long-range fibre-optic communications systems. LEDs are formed by the so-called III-V compound semiconductors related to gallium arsenide. They consume little power and are long-lasting and inexpensive