Technical LED Headlights

[Gavv8]

Two things......firstly how did you stop the canbus throwing up an error? and secondly have any of you ever had a BMW/Audi/Range Rover behind you with those HID projector headlamps??.... they are blinding in the extreme and they are legal??.... get of your high horses people.

 

[AB100]

have any of you ever had a BMW/Audi/Range Rover behind you with those HID projector headlamps??.... they are blinding in the extreme and they are legal.

Ain't that the truth. To be honest, I find many of the DLRLs a bit too bright. Specially the Citroen DS Christmas tree setup.

 

[Most Easterly Pandas]

BMW/Audi/Range Rover behind you with those HID projector headlamps??.... they are blinding in the extreme and they are legal??.... get of your high horses people.

Nope not dazzling at all if correctly setup - hence being legal.

The issue is people having shunts pushing them out of alignment and not being repaired correctly, or just like standard bulbs, changing them when they blow and not seating them correctly.

99% of OEM HID setups I've never had an issue with as another road user having them coming towards me.

 

[Gavv8]

They are dazzling, enough to make me dip my mirror as they hurt my eyes.

 

[Wee Smurf]

Irrespective of the legal issues one of the biggest constraints of the led lights on the Porsche macan, seat Ibiza etc is the heat. All these new units have a fan like a computer to keep the components cool, it is a big issue and now one of the basic starting points if you are designing a new led headlamp assembly. How does your new kit deal with this heat?

Didn't someone who was on here almost have a fire after messing with the headlights set-up a few years ago?

 

[g8rpi]

Just to redress the balance here slightly... (or provoke further stern comments? - the latter I shall ignore)

The filaments in a halogen bulb are quite small, and wound into a compact cylindrical shape. The 'baffle' inside the bulb carefully controls light from the dipped filament so it illuminates about 195 degrees (angle) of the top part of the mirrored reflector (the 15 degrees beyond horizontal gives the upwards 'flick' to the left seen when the beam is shone on a wall. Because the point is slightly forward of perfect focus and only filling the top part of the reflector, it shines downwards at an angle. The physics of a parabola dictate this.

(see this page, half way down: http://uc.fmf.uni-lj.si/com/Parabola/parabola.html )

Aftemarket HID bulbs have a much larger 'blob' of glass, where the light shines from, and generally less of a baffle too. The light source is more diffuse too. This is why they don't work well when used with lights designed for halogen - because the size of the source is too big and fuzzy and so spills over into the 'wrong parts' of the reflector, causing poor beam shape, or dazzle.

For main beam, the halogen filament is right at the optical centre of the parabolic reflector and so sends a straight parallel beam forwards.

Aftermarket HIDs 'cheat' for dip and main by using a solenoid to physically push or pull the glass tube of the 'bulb' in and out - so more or less giving dip or main from just one source.

But, the LED lamps the OP refers to have two small, pinpoint light sources - about the same size as the halogen filaments. And these are precisely mounted with a baffle that controls where that light goes from the front-most LED, just like the halogen bulb. So, in principle at least, they can deliver the same, controlled dip beam pattern as the original bulb because they will only illuminate the 'right parts' of the reflector - but the beams will be brighter. So long as the lamp unit is aligned correctly, there should be no more dazzle (oncoming cars seeing part of the beam shining directly at them) than with the original bulbs.

Most of the buses in my area have been converted from halogen to LED headlights - and they are fine. Brighter, but well controlled light output.

The legality of these bulbs may still be in question, but the rules of physics (that parabolic reflector and a correctly placed point source of light) mean they should be able to give a well controlled but brighter beam - just like the original-fit LED headlights used by Mercedes, Audi and others...

Me? I use 130% brighter halogens (e-marked), and they are OK on the dark winding lanes around here But, every bulb in my house is an LED, and in time, all cars lights will be too. The filament bulb is pretty similar in concept to that designed by Joseph Swan in Darlington in the 1880s. Maybe now is the time to move forwards from that...?

Hi your are generally correct, but seem mixed up on light source size. HID are a near perfect point source, allowing performance optics of simple design. LED chips are an area source, often comprising multiple chips in one package. They need complex optics "tuned" to the particular chip. That is why there are no "Lx" standard replaceable LED bulbs you can fit in any LED lamp housing. Only modern computer adied optical design and reflector / lens manufacturing allow LEDs to meet the strict vehicle requirements. You can't put a LED or HID in a reflector and lens desigined for halogens and get them to work properly. If you could, Osram and Philips would be selling them.

Robert G8RPI.

 

[cdmoran]

After driving behind some new Range Rovers with factory fitted LEDs I say ban the bloody lot of em. They are very dangerous lights imo!

 

[Most Easterly Pandas]

After driving behind some new Range Rovers with factory fitted LEDs I say ban the bloody lot of em. They are very dangerous lights imo!

Nope, not at all, whats you're issue with them?

Far better than standard filament bulbs, faster reacting which reduce rear end shunts!

 

[cdmoran]

Correction - I meant driving in front of Range Rovers with Xenon bulbs and lenses fitted. Sorry - must have been half asleep this morning when posting!

 

[VIP]

Here's what the consequences might be:

1. The police pull you over the first night you drive with these fitted

2. They phone your insurers to find out if they've been declared as a modification

3. The insurers say "no" and say you have broken the terms of your insurance, confirm you're not covered and cancel your policy

4. The police issue you with a fixed penalty ticket for no insurance and have the car towed away

5. You are left to walk home contemplating 6 points on your licence, a £300 penalty, the same again to recover the car, and a massive hike in insurance for the next few years for having failed to declare a modification, having insurance cancelled by the insurer and driving an unroadworthy vehicle.

Furthermore, if you are involved in an accident and someone is killed or seriously injured, the consequences could be much, much worse; you could end up paying the bills for the rest of your life. That someone could even be you, in which case you will have paid for this with your own life.

The construction & use regulations are there for a very good reason, but there's always some eejit that thinks they know better.

It's a common misnomer, but if you have an insurance policy in place, you cannot be prosecuted for having no insurance, regardless of the vehicles's conformity to the policy.

Certainly your insurer can refuse pay out if you're found to have non-declared modifications, but legally insurance companies HAVE to provide minimum Third Party coverage on an active policy.

Certainly any insurer can cancel a policy, but they are not allowed to do with instant effect that would leave a vehicle on the road with no policy in force.

 

[Most Easterly Pandas]

It's a common misnomer, but if you have an insurance policy in place, you cannot be prosecuted for having no insurance, regardless of the vehicles's conformity to the policy.

Certainly your insurer can refuse pay out if you're found to have non-declared modifications, but legally insurance companies HAVE to provide minimum Third Party coverage on an active policy.

Certainly any insurer can cancel a policy, but they are not allowed to do with instant effect that would leave a vehicle on the road with no policy in force.

Although generally you're are correct, in a few some circumstances, an insurance policy can void back to inception and provide no cover, but this is providing they can't be held under article 75 of the RTA and so on an so forth.

 

[TOX1C]

To update this thread, the H4 LED bulbs were cr*p, had a poor dip beam pattern although mains were excellent. They went back to the supplier, who claims not to have received them - but that's another story.

I have now fitted the "Blue Vision" bulbs from Philips, these are better than the 130% bulbs mainly because the colour is 4300 Kelvin rather than being slightly "warm".

I am considering fitting projectors; replacing the H4 bulbs in their entirety but will probably do this to the GTA before considering the Panda.

So all other road users and the barrack room lawyers can rest easy.