The headlights are the lights on the vehicle. The lights can be divided into front lights, rear lights, turn signals, license plate lights and other major categories. The front lights are generally in front of the whole car. There are two, one left and one right, which are axisymmetric. It mainly plays a role of illumination. The light from the headlights can illuminate the front of the car, allowing the driver to drive safely in the dark. There are many types of front lights: headlights (halogen lamps), xenon lamps, fog. Lights, front position lights, LED lights, daytime running lights and turn signals for every car. The rear light is at the rear of the whole car and consists of two parts, one left and one right, which are axisymmetric. The rear lights are mainly used to remind people behind the vehicle (including pedestrians and drivers). The rear lights usually consist of four parts: brake lights, turn signals, reverse lights and rear position lights. The license plate lighting is hidden above or to the left and right of the two front and rear license plates. It is mainly a lighting license plate that allows people to identify vehicles in the dark. When the current light is activated, the license plate illumination will automatically start.
Classification of front lights
Halogen headlight
A halogen lamp is actually a special kind of incandescent lamp. The principle is that when a current flows through the resistor, it will generate heat. When the temperature is high enough, the black body radiation with a wavelength in the visible light band will be emitted. There are generally two types of halogen lamps: iodine tungsten lamps and bromine tungsten lamps, the principle is the same. When the incandescent lamp is lit, although the filament temperature does not exceed the melting point and boiling point of tungsten, a small amount of tungsten is volatilized at a high temperature. When the volatilized tungsten atoms encounter a cold bulb envelope, they will condense and precipitate. Over time, the bulb shell will accumulate a blackened tungsten film. Ordinary incandescent lamps have been used for a long time. If the bulb is filled with some iodine, when the bulb is lit, the iodine will volatilize into a gas, and the iodine vapor will react with the colder tungsten to form a low-boiling compound, tungsten iodide, which will make the bulb envelope. The precipitated tungsten volatilizes. The tungsten iodide gas decomposes at high temperatures. When the tungsten iodide gas encounters the filament, it decomposes, leaving the tungsten on the filament, while the iodine continues to liberate in the form of a gas between the filament and the outer casing. When it comes to the bulb casing again, it will be on the outer casing. The tungsten reaction, on the one hand, keeps the tungsten volatilized onto the bulb casing, and on the other hand, the iodine continuously transports the tungsten back to the filament, so that the speed of filament evaporation is greatly reduced, and the bulb life is prolonged. Thus, a high-power incandescent lamp, such as 1000w, can be fabricated using a tungsten iodine lamp. If you do not add halogen, if the ordinary incandescent lamp is so powerful, the life will be short and difficult to use. Halogen lamps have been widely used in automotive lighting.
Xenon headlights
Xenon lamp HID is the English abbreviation of HighintensityDischarge high-pressure gas discharge lamp, which can be called heavy metal lamp or xenon lamp. Its principle is to fill a variety of chemical gases in a UV-cut UV-resistant quartz glass tube, most of which are inert gases such as Xenon and iodide, which are then passed through a booster (Ballast). The 12V DC voltage is instantaneously boosted to 23,000V, and the helium electrons in the quartz tube are excited by the high-voltage amplitude to generate a light source between the two electrodes. This is called gas discharge. The white super-strong arc light produced by helium can increase the color temperature value of the light, similar to the white sun light. The current required for HID operation is only 3.5A, the brightness is three times that of the traditional halogen bulb, and the service life is longer than the traditional one. Halogen bulbs are 10 times longer. More and more xenon lamps have been used in the field of automotive lighting.
Fog light
It is installed at the front of the car at a position slightly lower than the headlights, and is used to illuminate the road when driving in rainy and foggy weather. Because of the low visibility in the fog, the driver's line of sight is limited. Light can increase the running distance, especially the yellow anti-fog light has high light penetration, which can improve the visibility of the driver and surrounding traffic participants, so that the car and pedestrian can find each other when they are far away or when visibility is low.
LED light
LightEmittingDiode, referred to as LED, Chinese name is LED. The LED strip refers to the assembly of the LED on a strip-shaped FPC (flexible circuit board) or PCB hard board, and its name is named like a tape.