What is the most important electric appliance in a car? Definitely the lights. If there is no automobile light, no one can drive his car smoothly at night. There is no doubt that high quality light source add safeguard to our road trip at night. In this case, better light source is what car owners and manufacturers pursuit. The automobile lights which change from the simple use for lighting, to night vision, decoration and other purposes has developed very fast.
So how did automobile lights come onto being? As the automobile first appeared, it had very few function, let alone a light. It is said that in 1887, a driver got lost in a dark forest, but luckily he was helped by a farmer who light up his way with a barn lantern. This barn lantern was known as the earliest light on the car. As people’s need for auto light duality improved, spiral tungsten light showed up, which was a real start of the automobile lighting electrification history. Before the spiral tungsten light showed up, there are still some kind of light, but due to their shortcomings, they existed for a very short time. However, the luminous efficiency of normal tungsten light was not high, so the more energy-saving halogen light was born. In fact, halogen light is the updated version of tungsten light, which adds halogen element in the tungsten light. The application of halogen elements can increase the brightness of incandescent light by 1.5 times, and the service life by 2-3 times that of ordinary incandescent lights and can also eliminate the darkening phenomenon of the bulb shell.
In modern times, traffic environment has changed and the safety and environmental protection of the automobile have also improved. Halogen light cannot satisfy the need of automobiles for high speed and driving in poor visibility conditions. Also the energy consumption of halogen light is quite large. Only one halogen light’s power can be 50-70w. As halogen light is based on the electrification of tungsten filament, it has only 200-300h lifespan due to the loss of the high temperature.
In order to solve the halogen light problem of low brightness, large consumption, short services, etc., high intensity discharge lamp (HID) come into existence. The luminous theory of HID is to fill Xenon that is a kind of hyperbaric inert gas into the quartz burner. It supersedes filament, and the light is close to the sun light, which shines through the stimulation of 23000v high voltage electric current.
|Halogen light (55W)||1000lm||3000K|
However, HID also has some defects. The biggest problem is that some HID will cause dazzle to the driver right in front, which will cause accident. The HID needs 3-4s to reach the rated brightness. If at that time the driver wants to warn the coming car with the low beam, there will be a few seconds delay, which may cause accident. Also the price of HID is a little bit high, which will make car owners hesitate.
In recent years, as the technology has developed, a new type of light appears—LED (Light Emitting Diode) light. Led light has lots of advantages comparing to HID, such as energy-saving, long lifespan, wear resisting, easy to be lighten up, low loss and so on. LED, a solid-state semiconductor device, can directly transmit electricity into light.
|Economical performance||55w(generally)||35W(normally)||1/2 of halogen light|
|luminous effect||balanced||concentrated, both side dark||few error, without filter|
Though many automobile lights are made of HID when they leave the factories, LED seems to be better choice for automobiles in every field. As the world trend of combination between the automobile electronic techniques, many light company develop new type of LED chips in order to improve the performance of LED lighting, Cree in America, Osram in Germany, etc. are high quality chips in the world. In the future, LED lighting will be a great hit in automobile.