Light Emitting diode bulbs are essentially different from traditional incandescent bulbs both in structure and in light. A diode is a common component in an electronic circuit, which is made of a semiconductor PN Junction plus an electrode lead and a tube shell. The diode has a PN junction of two electrodes, so called the diode. Diode has one-way conductivity. There are many kinds of diodes, such as detector tubes, rectifier tubes, regulators, switch tubes, damping diodes, light-emitting tubes, photoelectric tubes and so on.
Light-emitting diodes are usually made of gallium arsenide, gallium phosphide and other semiconductor materials, it shines through the positive current, the luminous color depends on the material used, can emit red, yellow, green and infrared light. The light-emitting diode is usually made of transparent plastic package, the pin length is the positive pole, and the tube pin is short. Some light-emitting diodes have three pins, and can emit two colors of light according to the voltage of the tube foot.