In this system, the light going up from the bulbs forms the high beam and the light going going down (below horizontal plane) is the low beam. The Projector based system (with shutter) like HB3 has a reflector as well as a collimator lens. Let me share a quick hand drawn image of the ideal Led orientation for both projector and reflector based systems. LED retrofit will only get better in the future as the technology evolves and it will becuase they are already legal in many places. With the 50W 4200K LEDs I don't miss the halogens. Only caveat choose the LED light source wisely, buy quality. Ease of installation, reliability, beam pattern and light output. Now with the quality LED retrofits available burnt reflectors are a thing of the past and when installed correctly they output a perfect beam pattern, more light and less heat.Īs someone who has run reflector headlights with various high wattage halogens (Hella, Philips, Osram, GE), then HID retrofits (a lot of light everywhere) and gone back to high wattage halogen all I can say is that the LED retrofits are a boon. Only the glass and metal headlights could run 100W and higher halogens safely for prolonged periods without damage. This is happens more so with high wattage H4 halogens with that low beam filament cup directing all the heat up into the plastic reflector. In the past we used to get burnt reflectors (just above the bulb) and fast deteriorating plastic lens when used with high wattage halogens in a plastic headlight. In many of these countries using a retrofit LED in reflector lights are legal as long as the LED bulb is certified legal eg Philips 9xxx, Osram (not the 50W/25W ones sold here) and a few other makes. In the halogen lamps its heat could melt the frost on the lens which the LED lights cannot, because they don't produce much heat inside the reflector and lens assembly. This is a transparent film applied on the exterior of the headlight lens, its function is to melt frost as it accumulates on the headlight. In cold weather countries an interesting product is available in the aftermarket called headlight heaters. There is considerable temperature to manage even at 50% because LEDs become less efficient and then die if temperature rises. The warm whites are less efficient than cool white due to additional filter on it. This reduces efficiency to about 40-50% depending on the type of bulb it is. UV emission is also not a problem with LEDs as the Light emission spectrum is tightly controlled and light from UV ranges is not allowed to be generated for visible light LEDs.Įxcept for white LEDs - since they are blue and then converted to white through some sort of Phospor mix.
So headlights which are designed for working with Halogen bulbs can easily accomodate LEDs as the heat output will be 1/4th of the original heat output. But because the filament in bulbs is meant to be hot (it reaches 2000 Degrees) and is not affected by heat, you do not need any cooling system to cool the filament. In the case of halogen bulbs a 55w bulb will give off almost 85% of the energy consumed as heat - so almost 47w is given off as heat while only 8w is converted to light. The heat generated though is very minimal (10w). Hence it is necessary to have a fan in high wattage leds to draw away the heat from the led chip and keep it cool. This heat generated however can be harmful for the led diode as if the junction temperature gets high (say above 150 degrees) the led chip will fail prematurely. So out of 50w which an led consumes, 40w is converted to light and only 10w is given off as heat. Leds emit 80% of their energy consumed as light and only 20% of it is wasted as heat. This is a misconception and let me clarify on this aspect. With the limited amount of cold air available to the LED, how long before it overheats and starts affecting the life of a projector/reflector? I've not seen anyone debating on this so any info on it will be helpful. Nexon and other Tata cars have a closed headlight housing to prevent dust and moisture penetration. I'm sure they produce a lot more heat and a fan is added to maintain the temperature, but how effective it does that job is a question. Looking at these LEDs from Osram and other manufacturers, I can't help but think about their cooling mechanism and how it'll affect the life of the reflector or halogen projector.
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