One of the most common usages of the diode is LED (light-emitting diode) which demonstrates an interesting phenomenon of producing light. When the voltage on the LED reaches the required to forward bias the diode, the cavities and electrons of the depletion layer connect themselves and convert this electric energy into light. The color of the emitted light depends on the semiconductor material which emits photons of a specific wavelength. The forward voltage drop of the diodes producing different colors differs and must be consulted in the technical specification.
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