Frequently Asked Questions
LED is English Light Emitting Diode, namely light-emitting diode, is a kind of semiconductor solid state light-emitting device. It uses solid semiconductor chip as light-emitting material. When both ends are applied with forward voltage, carriers in the semiconductor recombine to cause photon emission. Light.LED can directly send red, yellow, blue, green, green, orange, purple, white light.The first commercial diode was produced in 1960. Its basic structure is an electroluminescent semiconductor material, placed A lead frame, and then surrounded by epoxy seal, play a role in protecting the internal core, so the seismic performance of LED good.
According to the light-emitting mechanism of electric light Category: The first generation of light source: light-emitting resistance such as incandescent lamp. The second generation of light source: arc and gas glow such as sodium lamp. The third generation of light source: phosphor light such as fluorescent light. Fourth generation light source: Such as LED.
LEDs are made of Group III-IV compounds such as GaAs
(Gallium arsenide), GaP (gallium phosphide), GaAsP (gallium arsenide phosphide) and other semiconductors, its core is the PN junction. Therefore, it has a general PN junction of the IN characteristics, that is, , Breakdown characteristics. In addition, under certain conditions, it also has a luminescent properties in the forward voltage, the electron from
The N region is implanted into the P region, and the holes are injected into the N region from the P region. Part of the minority carrier (minority carrier) entering the other area and the majority carrier (multiple carrier) recombine to emit light.
1.LED light emitted is neither monochromatic light nor broadband light, but the balance between the two. 2.LED light source is like a point light source but not a light source. 3.LED light color varies with the space direction is different .4. The LED junction temperature under constant current operation strongly affects the forward voltage VF.
LEDs are different in their chemical composition due to their different colors: Red: Aluminum - Indium - Gallium - Phosphide Green and Blue: Indium - Gallium - Nitride White and other colors are mixed with RGB trichromatic colors in the appropriate proportions and LED manufacturing process is similar to the semiconductor, but the processing accuracy is not as good as the semiconductor, the current cost is still high.
At present, several commonly used ultra-bright LED light spectrum wavelength distribution of 460 ~ 636nm, wavelength from short to long followed by a blue, green, yellow-green, yellow, orange, red. The typical peak wavelength is: blue- 470nm, Cyan - 505nm, Green - 525nm, ** - 590nm, Orange - 615nm, Red - 625nm.