The difference between halogen projector headlamps and bmw f10 h7 led
Many people say that halogen projector headlamps are the upgraded version of incandescent lamps, while bmw f10 h7 led is a new era of high-tech lamps, a thousand times better than halogen projector headlamps. Is this really true, and what is the difference between them? Here's a look from several angles.
1、The principle is different
Halogen projector headlamps is the traditional incandescent bulbs in the injection of iodine or bromine and other halogen gas lamps. Its light-emitting principle is that the tungsten filament heats up under high current, and when it reaches an incandescent state, it will glow outward. And the core of bmw f10 h7 led is the light-emitting diode. The principle of luminescence is the light-emitting diode in the energized state will excite photons to radiate energy outward, which leads to luminescence.
2, the light effect is different
The so-called luminous efficacy is the luminous flux emitted by the light source and the ratio of power consumption, also known as luminous efficiency, the unit is lumens / watt. halogen projector headlamps because it is through the heat to the incandescent state of light, the input power is used in addition to light, a small part of the consumption in the circuit, there is a large part of the conversion of the tungsten filament heat. halogen projector headlamps are also figuratively called thermal light sources, light efficiency is relatively low, generally between 20-28 lumens per watt.
And bmw f10 h7 led is through the electron in and hole compound excitation of photons and light, so, LED lights in the work, excluding the heat on the circuit, the other power is all used for light. Also known as a cold light source, light efficiency is higher compared to thermal light sources. Generally between 48-140 lumens per watt.
3, the spectrum is different
As halogen projector headlamps belong to the thermal light source, so it emits the spectrum follows the black body radiation. Spectral continuity is very good, basically has the same color rendering of sunlight. And its color temperature is generally at 3000K+, which is a warm tone. When viewed with the naked eye, it will give a warm and comfortable feeling. At the same time, because of Rayleigh scattering, the lower the color temperature of the light, the stronger the penetration in the rain, fog and sandy weather.
And bmw f10 h7 led belongs to the cold light source, it is through a chip that can emit blue light, excite the chip coated with yellow phosphor, and then mixed with part of the excess blue light to form white light. This spectral continuum is not as good, and the color temperature is basically around 6500K. The naked eye is very bright, but also very harsh. This is also the reason why we often see the car LED high beam on the road is very harsh.
4. Different life span
Halogen projector headlamps are not afraid of heat, but its life and light efficiency has a lot to do with it. If you want to improve the light efficiency, halogen projector headlamps life will be reduced. Normal light effect halogen projector headlamps generally have a life of about 500 hours, long life version can reach 2000 hours of life, high light effect version life is much shorter.
And bmw f10 h7 led life is different, it does not have much to do with light efficiency. Basically, the life of the light-emitting diodes, now on the market generally have a life of 50,000 hours, this life than the long-life version of halogen projector headlamps also tens of times higher. However, LED lamp life will be reduced as the working temperature rises. Therefore, LED lights must do a good job of heat dissipation, to ensure that the heat generated by the drive circuit to dissipate heat in a timely manner.
Halogen projector headlamps because of the simple structure, cheap materials, mature technology, so the price is very cheap. LED lights are different, in order to do a good job of quality, lamp beads, heat dissipation, the cost of the driver circuit is relatively high. Therefore, the price will also be much more expensive than halogen lamps.
Halogen projector headlamps are thermal light sources, compared to Bmw f10 h7 led has a more continuous spectrum, lower color temperature. Therefore, the penetration is stronger, and the human eye is warmer and more comfortable. At the same time, the price is also cheap. And LED belongs to the cold light source, compared to halogen lamps have a higher luminous efficiency, longer life.