How long before manufacturers start using LEDs instead of incandescent bulbs for exterior lighting? Already many high level stop lights are LED so why not replace the other low/medium wattage lamps too?
They illuminate almost instantly so are safer.
They have an almost infinite lifespan - at least compared to the vehicles they are fitted to - so there would be fewer cars driving around with one or more lights not working. Again, safer.
OK they'd cost more initially but economies of scale should reduce that.
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I don't think LED's are legal on their own, which is why they are used in supplimentery high level brake lights and not in the main ones. The same applies on bicycles where LED's are not legal as the sole means of lighting.
It has something to do with the wording of the law which states that a buld must show a steady light, whereas LED's actually flash, although at a rate not discernable to the eye.
A case of the law being slow to catch up with technology.
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Extraordinary. The sooner the law gets into the 21st century the better, I'd say.
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LED's are certainly being used on many new large vehicles as position lamps etc - and I have a feeling I've seen these on some 'luxury' cars too?
They're also now being used on some new traffic lights and temporary traffic lights, too.
Neil
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Neil, as you say, many HGV side marker lights are LED lamps.
The trouble is they fail regularly, usually due to water ingress.
This means replacing the whole lamp unit rather a bulb. I now replace the LED units (when they fail) with an ordinary bulb holder unit. Quick and easy to replace a bulb.
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All my brake lights are LED and the rest are fibre optic.
The new BMW M3 has the complete rear light cluster just as LED's, brake lights, reversing and normal rear lighting.
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Where BMW leads let's hope others follow.
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somewhere above - LEDs don't flash if they're fed with DC.
The later local buses round here have LED tail and stop lights - these appear to be manufactured in rather than addons. A lot more visible.
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Except with regard to 'flame surfacing', one hopes.
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The rear lamps of many modern motorcycles and upmarket BMWs and Mercs are LEDs already.
Most of the power consumed by a filament bulb is lost as heat. Very little light.
LEDs are lighter, brighter, cheaper, last virtually forever and ARE SAFER as they illuminate almost instantly. No 0.5sec loss waiting for filaments to heat.
I vaguely remember Volvo fitting them for that reason.
This covers rear and stop lamps.
For headlamps there's Noble gas discharge ie helium, neon, krypton, xenon. I think xenon are marketed currently for top range cars.
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I gather from a local garage owner that plans are already afoot to fit a central box of LED's for everything except headlights, and distributes the light via fibre-optics. This simplifies installation, reduces hardware (especially at the corners) and should improve reliability. Downside is that you will have probably have to replace the box if anything goes wrong...
Not sure how this squares with UK regulations specifying 21 Watt and 5 Watt lamps, although those may just be upper limits, in which case LED's are fine. It also means that you will be able to leave your sidelights on almost indefinitely!
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When I went to the local MB dealership asking for a bulb kit for driving in Europe he said they didn't make one for certain E-Class models.
Apparently I dont need one because all the brake lights are LED's, the rear light clusters work off fibre optics and my headlights are Bi-Xenon.
It all sounds very good but how much will it cost me when things do go wrong?
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The UK regs requireing a candescant filament bulb should be repealed. Also the regulation specifying 21 watt and 5 watt
is archaic, this refers to the power consumption, most of this power is converted to heat and not light, the regulation should specify the light output in Candela and leave it up to the manufacturer how to generate this.
Traffic lights are increasingly being converted to multiple LEDs now that red, yellow and green LEDs are easily available, blue and even white LEDs can be purchased at reasonable cost these days.
regards
Ian L.
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"the regulation specifying 21 watt and 5 watt
is archaic"
I agree entirely, but while it's on the statute book, I should be very tempted, if dragged into court on a speeding charge, to draw attention to the state of the tail lights on the chief magistrate's Mercedes...
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You're all missing quite a key point here though.
Sure LEDs are excellent for brake lights as they are as good as instantaneous and rarely fail.
Where should LEDs really be employed though? On most cars it's a 5 minute job to change an external bulb. You try changing a speedometer or other dash light. On many modern day cars it is a massive, entire dashboard removal job - maybe a days work.
And yet manufacturers still persist in the use lightbulbs...
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Agree about the replacement of dashboard bulbs with LEDs, but the point about the 5 minute job to change an external bulb is that (as tens of thousands of car drivers show) many cant be bothered to check/replace blown bulbs, if they didnt blow in the first place
then failed brake/tail/indicator/side lights could be a thing of the past, suitable LEDs for all these applications are already available.
Ian
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Im pretty sure that the dashboard is now lit using fibre optics on my MB so to change a lamp is a piece of cake and needs no form of dash removal at all.
It's got to be the way forward.
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Im pretty sure that the dashboard is now lit using fibre optics on my MB so to change a lamp is a piece of cake and needs no form of dash removal at all. It's got to be the way forward.
FIAT UNO 45S E reg has fibre optics for the lamps of the dash switches with a single bulb that is accessed by just unclipping the instrument binnacle cover.
No tools required for the job.
Good idea FIAT but poor illumination.
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>> Im pretty sure that the dashboard is now lit using >> fibre optics on my MB so to change a lamp is >> a piece of cake and needs no form of dash removal >> at all. >> It's got to be the way forward. >> FIAT UNO 45S E reg has fibre optics for the lamps of the dash switches with a single bulb that is accessed by just unclipping the instrument binnacle cover. No tools required for the job. Good idea FIAT but poor illumination.
And even earlier than that, didn't the Austin Princess also use fibre optics for the dash lighting?
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Well the lighting on the dash of my Merc is fantastic so why dont more manufacturers use this system.
Ive worked with fibre optical lighting on boats and buildings and it works a treat for lighting confined spaces where access is difficult.
Come on car manufacturers, sort yourselves out.
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And even earlier than that, didn't the Austin Princess also use fibre optics for the dash lighting?
Yepp it did, just another example of how advanced BL was in many ways. Let down by details.
---------------
Don't vote it only encourages them.
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On most cars it's a 5 minute job to change an external bulb. You try changing a speedometer or other dash light.
On the Mk IV Golf it certainly wasn't a 5 minute job to change the nearside headlamp. To do it properly you had to remove the battery. Luckily, the VW dealership in stoke never charged me labour to do the change, so I always had then do it.
It looks even worse on my Passat
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The new traffic lights in the town center are all LED lights. They can be quite dazzling late at night.
The Audi Novularo concept car has LED headlamps that can turn around corners simply by switching some on and off (no moving parts). They are supposedly just as bright as Xenons, but I'd need to see them in the flesh before I'll be convinced.
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A firm I work for has just produced some high-brightness indicators to assist with ship berthing. These have previously been 500W halogen lamps that have a nasty habit of overheating when you put a coloured filter in front of them, but the new LED versions (each has a grid of 160 LED's) consume about 20W and are too bright to look at directly. I don't know what the life expectancy is, but they can afford to lose one or two...
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This is one of the principles of LED use in these applications - use enough so that you need a fairly high failure rate to warrant replacement. Depending on the application though don't forget that while a halogen has a pretty wide light output angle, LEDs are more focussed, so if you need such an output they will have this as a further advantage over more traditional luminaries.
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Trouble with LEDs for dashboard illumination is that they have a fairly narrow output angle and the spread of light output isn't too clever either. Positioning would be more difficult and you'd need plenty of reflectors and the like. Anyway, I'd prefer everything to go VFD as in the Yaris - much nicer.
As for LED reliability, they aren't actually all that good. To get any decent amount of light out of them to need driving fairly hard which leads to early failure. (They are a semiconductor junction and so can fail just as easily as any other piece of electronics) Also, they are't too hot with vibration and shock. It'll get there one day, but I don't think that day will be for another 5 or 10 years.
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What I don't get is that people are going on how unreliable LEDs are, yet the first real automotive application for vehicle positioning lights, indicators and brake lights has been seen on heavies and buses.
This is simply driven by economics, ie a bulb might cost only a few pence to buy, but its the cost of the off road time, vehicle fitter what have you is more than offset by the increased reliability.
In my opinion the transport haulage and bus industries don't spend unless the payback has been fully examined.
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I must admit that it's hard to see how an LED can be less reliable than a white-hot piece of wire bounced around between two thin metal prongs! If there is a problem here, I think it will be designed out pretty quickly - there's rapid development in this area.
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As a graduate with an electronics degree I wish I could join in with this thread, but since leaving university I haven't had need to use my knowledge of electronics, so it's all gone :-(
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LED's ARE a lot more reliable than a filament type lamp, simple as that. As mentioned before a white hot piece of metal will only take so much beating around but an LED will take an awfull lot more.
A normal filament lamp has a life expectancy of around 10,000hrs if lucky but an LED should have a life expectancy of around 100,000hrs.
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LEDs have different failure modes to bulbs and in some ways for automotive applications are not that much more reliable than bulbs. However, the main advantage is that while they are very hard to replace, they are used in high multiples so the odd one failing does not affect the overall effect. You talk about a white-hot piece of metal taking a beating, but don't forget that LEDs have fairly fine wires connecting the die to the pins which can suffer similar problems.
Personally, I think LEDs will have limited use - once OLEDs and EL film is better developed I can see that being a better replacement for traditional filament lamps.
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Er, isn't an OLED (organic LED) still an LED? They're also patented by Kodak, IIRC, so likely to be expensive.
In any case, ordinary LED's are likely to be subject to a similar rate of development. They seem to have done pretty well so far, and anything that replaces hot bits of tungsten running at 1% efficiency has got to be an improvement!
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LED is a very broad term! I'm pretty sure OLEDs aren't anything to do with Kodak - there is a company in Cambridge that is doing a lot of work on them at the moment.
Ordinary LEDs are developing - it's only fairly recently that a 'true' white device was launched and even then they have awkward drive requirements. Certainly in many applications they have the edge on filament lamps, but they aren't a 'cure-all' either.
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\"Eastman Kodak Company has led OLED research since its scientists discovered OLED more than a decade ago.\"
From Kodak\'s website, admittedly!
Agree with the general thrust of your argument, though. It\'s just that almost anything would be an improvement on incandescent bulbs, which must be one of the last 19th century inventions in general use, largely unmodified!
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