Key Features of Automotive LED Lights

1. Reliability and service life

The expected lifespan of LEDs is 50,000 hours, compared to 20,000 hours for tungsten halogen lamps and 3,000 hours for tungsten incandescent lamps. Compared to incandescent lamps, LEDs are structurally robust, not susceptible to vibration, and the light output brightness does not decrease significantly during use. Lighting solutions based on multiple LEDs also have the benefit of "redundancy", allowing the lighting unit to continue to be used even if one LED fails.

Proper use of LEDs (especially properly controlling the temperature of LEDs) can effectively extend the life expectancy of LEDs. On the contrary, LEDs are easily damaged if the temperature is too high. The application of LEDs to automotive lighting also involves many legal definition issues. Most countries have a clear definition of brake light or headlight failure - when the light is on or off. But for lights with multiple LEDs, it is difficult to accurately define whether the lighting has been damaged. Manufacturers and legislatures are defining how LEDs are used.

2. Efficiency/lumens per watt

Compared to standard incandescent lamps, LEDs can produce more light output per unit of power consumed. But the advantage of LEDs' actual light output is not obvious when compared to halogen lamps. The latest LEDs have excellent lumens per watt values, but some values are achieved under optimized conditions, not usually at the highest output conditions. In general, when the current of the LED increases, the amount of light output does not increase linearly. Therefore, even if the LED outputs x lumens at 0.5A current, it will not output 2x lumens at 1.0A.

3. Response speed

Taking brake lights and directional indicator tubes as an example, assuming that the vehicle speed is 125 km/h, that is, 35 m/s, the hot start time of the incandescent lamp is about 250 milliseconds, and the fast-responding LED can issue a brake warning about 8 meters earlier, thereby effectively avoiding car collisions. The same goes for indicator lights.

4. Directionality

Another key feature is how LEDs emit light. Unlike incandescent lamps, LEDs emit light through only one surface, which is good for headlight and chart lighting applications, but may not be suitable for carriage lighting and other lighting applications.