LED Light Source

- May 01, 2020-

LED (Light Emitting Diode), light emitting diode, is a solid-state semiconductor device that can directly convert electricity into light. At present, it is being used in more and more vehicles, such as LED far and near beam lights, LED tail lights, high-level brake lights, daytime running lights, etc.


LED structure


    The heart of the LED is a semiconductor chip. One end of the chip is attached to a bracket, one end is the negative electrode, and the other end is connected to the positive electrode of the power supply, so that the entire chip is encapsulated by epoxy resin. The semiconductor wafer is composed of two parts. One part is a P-type semiconductor, in which holes are dominant, and the other end is an N-type semiconductor, where mainly electrons. When these two semiconductors are connected, a "P-N junction" is formed between them.


working principle


    When current flows through the wire to this chip, the "PN junction", the electrons will be pushed to the P region, where the electrons recombine with holes, and then emit energy in the form of photons, which is LED light emission Principle. The wavelength of light, that is, the color of light, is determined by the material forming the P-N junction.


LED advantages


    1. Energy saving and low cost: LED has high luminous efficiency, nearly twice that of fluorescent lamps. If we use our daily energy-saving lamps as an example, energy-saving lamps are 4/5 more energy-efficient than incandescent lamps, and LEDs are 1/4 energy-saving than energy-saving lamps. In the car, the same daytime running lights, LED components consume only 1/20 of the energy consumption of halogen lamps. The cost of LED components has also been greatly reduced year by year, and the current cost and price are still falling by more than 20% per year.


    2. Long lifespan: At present, the LED components used in automobiles can basically reach the level of 50,000 hours, and well-known automotive lighting suppliers have been able to provide LED components with a life span of 100,000 hours, which is equivalent to 11 years ... .In consideration of the frequency of use of the lights, basically in the design life of the vehicle, LED components do not need to be replaced. In comparison, the life of a xenon lamp is only about 3000 hours ...


    3. Good durability: The structure of the LED element is simple, the impact resistance and shock resistance are very good, it is not easy to break, and it can adapt to various environments well.


    4. LED components are small in size, compact and convenient for layout and styling design: this is a huge advantage of LED. This advantage fully caters to the evolutionary needs of automotive manufacturers in design, breaking the shackles of past lighting systems to styling innovation, let us have More creative automotive products.


    5. Fast response speed: LED lighting only needs microsecond level. It can be used to quickly light up on tail lights and turn signals to achieve better warning effect. It is used on headlights, which has more advantages than xenon lights and halogen headlights. The high response speed has a better guarantee for driving safety.


    6. Low brightness attenuation: LED brightness is high, and the light brightness attenuation is much lower than halogen lamps, suitable for warning lights such as lighting and brake lights, turn signals.


    7. It can be driven by low-voltage direct current, with small load and weak interference, low requirements on the use environment and good adaptability. Unlike xenon lamps, booster devices (high voltage packages) are also required.