Light emitting diode (English: Light-Emitting Diode, referred to as LED) is a kind of semiconductor electronic component capable of emitting light. The electronic components in the early 1962, early emit only low luminosity red, after developing other monochromatic version, to emit light has spread today visible light, infrared and ultraviolet spectrophotometry, also increased to considerable spectrophotometry. And use is also at the beginning of time as the indicator, a display board; with the progress of technology, the light-emitting diodes have been widely used in monitors, television lighting decoration and lighting.

LED unidirectional conductivity

LED can only go in one direction conduction (electricity), called the forward bias (forward bias), when the current is flowing, electron and hole in the inner compound and emit monochromatic light, this is called electroluminescence effect, and the wavelength of light, the color with the kind of the semiconductor materials and the use of incorporation elemental impurities related. With high efficiency, long service life, not easy to be damaged, the switch has the advantages of high speed, high reliability than traditional light source. The luminous efficiency of white LED, in recent years there has been significant improvement, at the same time, in every 1000 lumens of the purchase price, but also because of influence of input market makers to compete with each other, and obviously decreased. Although more and more people are using LED lighting for office furniture, decoration, signs, and even street lamp uses, but technically, LED in the photoelectric conversion efficiency (the ratio of the effective illumination on electricity) remains below the fluorescent lamp model, is the country after the development of civilian to!