What is Automotive Lighting
Dec 19, 2022 View: 678
1. What is Automotive Lighting
The development history of automotive lighting generally goes through the following four stages: The evolution of automotive lamps occurs with the change of automotive light sources.
The first generation of automotive lighting systems produced light by direct burning of fuels (candles, kerosene or acetylene). However, there are obvious shortcomings such as low luminous efficiency, weak light intensity, unstable performance, and complicated operation. It can meet the requirements of early car lights.
The second generation of automotive lighting systems are incandescent lamps. Edison invented the incandescent light bulb in 1879. Revolutionary changes have taken place in automobile lamps. In 1913, the United States first applied incandescent lamp technology to Cadillac automobile headlights.
Since then, automotive lighting has entered the electrical age. Then, new technologies such as automobile reflectors, starters, generators and batteries appeared successively. In 1925, automobiles really entered the era of incandescent lamps and lanterns. In the 1950s, tungsten-halogen lamps appeared again, and soon became the main bulbs for strong light sources in automobiles. It will replace incandescent lamps and tungsten halogen lamps as the light source of new car headlights.
The third-generation automotive lighting system is a gas discharge lamp (HID), which has the advantages of high luminous efficiency, high brightness and high reliability.
The fourth-generation automotive lighting system is a semiconductor light-emitting diode (LED LED semiconductor PN junction diode. The PN junction system is excited, when a forward bias is applied to both ends of the PN junction. The carrier transitions from a low-energy state to a high-energy state. When the unstable carriers in the high-energy state return to the low-energy state for recombination, according to the principle of energy conservation, the excess energy will be released in the form of photons, which is the principle of LED electroluminescence.Car lamps are from the most primitive candle lamps.
In recent years, new HID lights and LED lights have appeared. Since the exposure of the first model of the Audi family to install LED headlights, the R8, it has developed into the commonly used incandescent lamps. International high-end car manufacturers such as Mercedes-Benz, BMW, Toyota, Ford, etc. have launched new models of cars equipped with colorful LED lamps to attract customers, especially Japanese cars have widely used LEDs. Known as the car lamp that does not need to replace the bulb for a lifetime, it is one of the most dazzling products in the world of automotive electronics.
Automotive lighting system mainly includes: exterior lighting fixtures, interior lighting fixtures, exterior signal lamps, and interior signal lamps. Car lamps are divided according to their functions and functions, and there are mainly two types: "car lights and car signal lights".
Automotive lighting includes: "headlights, fog lights, license plate lights, instrument lights, dome lights, and work lights" according to their installation positions and functions. Automobile light signal lights include: "turn signal lights, hazard warning lights, width lights, tail lights, brake lights, reversing lights".
2. The Working Principle of Automotive Lighting
Structural principles:
In order to facilitate the driving of the car and ensure the safety of driving, various lighting and signal equipment are installed on the car. Automotive lighting and signaling devices constitute an independent circuit system in automotive electrical equipment. A general car has 15-25 exterior lights and about 40 interior lights. This explains the important role of this system in modern cars.
The lighting system is mainly composed of three parts: lamps, power supplies and control circuits (including control switches). Lamps are divided into lamps for lighting and lamps for signals and signs. The lamps for lighting include headlights, anti-fog lights, tail lights, license plate lights, dome lights, instrument lights and work lights. I signals and signs are used for turn signals, brake lights, small lights, tail lights, indicator lights and warning lights.
3. Function and Application of Automobile Lighting
Types, characteristics and uses of lighting lamps:
Headlights: Commonly known as headlights, they are installed on both sides of the head of the car and are used for lighting when the car is driving at night or on dimly lit roads. There are two-light systems and four-light systems.
Fog lights: Installed at the front and rear of the car, the position is slightly lower than the headlights. The fog lights installed on the front of the car are called front fog lights, and the fog lights at the rear of the car are called rear fog lights. The light color is yellow or orange (yellow light has a longer wavelength and better disclosure performance). Used to improve road lighting conditions in harsh conditions such as fog, snow, heavy rain or dust.
Width indicator lights and tail lights: used to indicate the vehicle position and width to other vehicles at night. The lights at the front are called width indicators, and the lights at the rear are called tail lights. Both lights are low intensity lights.
Brake light: Installed at the rear of the vehicle, it informs the vehicles behind that the vehicle is braking to prevent the vehicles behind from colliding with its rear.
Turn signals: Installed on both ends of the vehicle and on the front fenders, the front, rear, left, and right vehicles indicate that the driver is turning or changing lanes. The turn signal light flashes 60~120 times per minute.
Hazard warning lights: When the vehicle is in an emergency stop or parked, the hazard warning lights show the location of the vehicle to the front, rear, left, and right vehicles. The turn signal lights flash together at the same time, that is, they are used as hazard warning lights.
License plate light: used to illuminate the rear license plate. When the tail lights are on, the license plate light is also on.
Reversing light: Installed at the rear of the vehicle, it provides additional lighting for the driver so that he can see clearly behind the vehicle when reversing at night, and also warns the vehicles behind that the driver wants to reverse or is reversing. When the ignition switch is turned on and the shift lever is shifted to the reverse gear, the reverse lights will be on.
At present, most of the combination of headlights, fog lights, width lights, etc. are called combined headlights; the combination of taillights, rear turn signal lights, brake lights, reversing lights, etc. is called combined rear lights.
Instrument lights: used to illuminate the instrument panel at night, so that the driver can quickly see the instrument. When the tail lights are on, the instrument lights are on at the same time. Some vehicles are also equipped with light control rheostats, allowing the driver to adjust the brightness of the instrument lights.
Dome Lights: Used to illuminate passengers in the vehicle, but must not dazzle the driver. Usually, the interior lights of passenger cars are located in the middle of the cab, so that the lights in the car are evenly distributed.
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