Vpis v blog od Vicky Wu
Automobile atmosphere lamps are indispensable as night lighting lamps. With the development of LED, more and more car manufacturers have adopted LED headlights as the first choice for car lights. LED car light refers to the use of LED technology for both interior and exterior light sources for external and internal lighting. External lighting equipment involves thermal limits and EMC issues, as well as many complex standards for off-load testing. LED car lights can be widely used to create the environment inside the car.
Structure of Mi2 automobile LED headlights:
A single LED is composed of gold wire, LED chip, reflection ring, cathode wire, plastic wire, and anode wire.
The core of the light-emitting diode is a wafer composed of a p-type semiconductor and an n-type semiconductor. There is a transition layer between the p-type semiconductor and the n-type semiconductor, which is called a pn junction.
In the PN junction of some semiconductor materials, the injected minority carriers and the majority carriers will release excess energy in the form of light, thereby directly converting electrical energy into light energy. A reverse voltage is applied to the pn junction, and minority carriers are difficult to inject, so it does not emit light. This type of diode made using the injection-type light-emitting principle is called a light-emitting diode, and is commonly called an LED.
The lighting process of LED includes three parts:
Carrier injection, composite radiation, and light energy transmission under forward bias.
Automotive Led Work Lights
Tiny semiconductor wafers are encapsulated in a clean epoxy resin. When the electrons pass through the wafer, the negatively charged electrons move to and recombine with the positively charged hole area. Photons are generated while the electrons and holes disappear.
The greater the energy (band gap) between the electron and the hole, the higher the energy of the photon produced. The energy of the photon in turn corresponds to the color of the light. Within the spectrum of visible light, blue light and purple light carry the most energy, and orange light and red light carry the least energy. Because different materials have different band gaps, they can emit different colors of light.
When it is in the forward working state (that is, the forward voltage is applied to both ends), when the current flows from the LED anode to the cathode, the semiconductor crystal emits different colors of light from ultraviolet to infrared. The intensity of the light is related to the current. For example, an LED is like a burger. The material that can emit light is the "meat pie" in the sandwich, and the upper and lower electrodes are bread with meat. And through the research on the light-emitting materials, people have gradually developed a variety of light color, light efficiency LED components are getting higher and higher, but no matter how changed, the overall light-emitting principle and structure of LED has not changed much.
Advantages of automotive LED work lights:
(1) Energy saving: The light-emitting diode directly converts electrical energy into light energy. The power consumption is only 1/10 of that of traditional lamps, which can better reduce fuel consumption and protect automobile circuits from being burned by excessive load current.
(2) Environmental protection: There is no ultraviolet and infrared in the spectrum, there is no heat generation, no radiation, little glare, and the waste is recyclable, contains no mercury elements, no pollution, and can be safely touched. It is a typical green lighting source.
(3) Long life: there are no loose parts in the lamp body, and there are no shortcomings such as easy burning, thermal deposition, and light decay of the filament. Under the appropriate current and voltage, the service life can reach 80 ~ 100,000 hours, which is longer than the life of traditional light sources. More than 10 times longer. (There is a replacement, the characteristics of lifetime use)
(4) High brightness and high temperature resistance. (The electrical energy is directly converted into light energy, and the heat generation is small, which can be touched by hand)
(5) Small size: The designer can change the lamp mode at will to make the car diversified. Car manufacturers favor LEDs, which is entirely determined by the advantages of LEDs themselves.
(6) Good stability: LED has strong anti-shock performance, resin package, not easy to crack, easy to store and transport.
(7) High luminous purity: clear and vivid colors, no need for lampshade filtering, light wave error is within 10nm.
(8) Fast response time: no need for hot start time, light can be emitted within a few μs, and traditional glass bulbs have a delay of 0.3s, which can effectively prevent rear-end collisions and ensure driving safety when used for tail lights.