Thoughts on LEDs for Automotive applications?

[Colinsdad]

I'm not sure this is the right forum to post this in, but, here goes....

The thought occurred to me after reading about Audis use of LEDs in their cars, that why hasn't someone offered an aftermarket, say projector light housing, that uses something like an SST90 or XML in it? I mean, if the crew at 4Sevens can come up with that XML beast spotlight that puts out 15000 lumens, why hasn't anyone marketed something auto related? I know there are some off road light bars that use unspecified LEDs in them, but, given the appropriate power source and cooling, it boggles my mind to think about what someone like Vihn, or Bryan at Shiningbeam could come up with!

Does anyone else have any thoughts on this? What emitter(s) do people think would work well in this application? For your perusal, here's a link to Audis LED page:http://www.audiusa.com/innovation/design/LED

Thanks for your input guys/gals!!

 

[AnAppleSnail]

The SST90 is not appropriate for use in car headlights. Check out the Automotive Lighting forum to see more information. Here is a typical thread.

In short, the requirements for a road-legal driving beam are very strict. It requires a lot of things to engineer a legal headlight. Any goofball can make an impressively bright "Off road nudge wink" light, but the qualifications to make a safe, legal, effective light that will survive the electrical, temperature & wet, vibration-heavy environment of a car is very difficult.

An SST-90 is too large to make an adequately 'shaped' beam for driving. To see what I mean, shine your car headlights against a wall - Notice the T- or +-shaped light profile that gives intense light to the distance, dim light nearby, and adequate light to see the road shoulder. A flashlight beam is nothing like an appropriate headlight.

Over 1000 lumen output is too bright for most driving conditions. Too much light is worse than not enough. With not enough light, one car on the road can't see. With too much, no cars on the road can see.

It's easiest for me to see MY posts about this, so here is an overview of what is required:

I wrote:
Shine a flashlight at your garage door next to your car headlamp beams. You'll notice that there is a definite shape to the car headlight's beam. These blobs and shadows light the shoulder, the road near your car, the middle distance, the far distance, and overhead highway signs, without blinding many drivers. Your flashlight would give a broad wash of light, either not lighting the road nearby or failing to reach far away, blinding all the drivers, and over- or under-lighting the shoulder.

Vehicle lighting is a safety device - For you to be seen, for you to see with, and for you to NOT blind others with. There are definite laws and requirements in all civilized countries. Vehicle makers (Lexus, Toyota) do a lot of testing to make sure their lights are safe. At least $20,000 in testing (Photometric study, weathering&aging, durability & electrical) is done on every headlamp design. The photometric tests are valid for one car, one type of lamp cover (The clear bubble over projector-type lenses), and one mounting location. Changing any of these invalidates the testing and means YOU are taking into YOUR hands a guarantee that your lights are at least pretty likely to not cause excessive glare, fail suddenly, or fail to light the road well. Lots of studies show that drivers' opinions of their headlights are often opposite real performance. Bright light nearby is comforting and detrimental to driving reaction distance.

In short, the advantages to LED lighting (Lower power consumption, long source life) are just about balanced by the weaknesses (Plastic headlight covers haze out within ten years, heavy LED heatsinks reduce gas mileage). AUDI uses exotic laser-source LEDs to give extreme control over beam shape. That's a unique advantage to the LEDs, and it pays off on the huge investment in qualifying the lamp.

 

[-Virgil-]

why hasn't someone offered an aftermarket, say projector light housing

Modular LED projector headlamps exist already. Hella makes several of them, as does JW Speaker. These two are OK. There's also one from Hamsar. Eventually these kinds of modular projectors will get better, but for now they are not at (or near) the top of the heap in performance. There are larger LED headlamps, made in the normal variety of round and rectangular standard sizes (to replace round and rectangular sealed beams). Some of these are really quite good, and they, too, are steadily improving.

I mean, if the crew at 4Sevens can come up with that XML beast spotlight that puts out 15000 lumens

A spotlight or a floodlight is optically much simpler than an automotive headlight beam. For that matter, the entirety of an automotive headlamp is much more complex than a spot or flood or flashlight. It's really not something that can be "workbenched" at home or in an enthusiast's workshop, no matter how enthusiastic the enthusiast might be.

 

[-Virgil-]

AUDI uses exotic laser-source LEDs

That's two different technologies. LED headlamps are here now, rapidly spreading to all segments of the market. Laser-activated remote-phosphor ("LARP") headlamps have just arrived, in the form of high-beam "booster" lamps from BMW and Audi. It will be a long time (in relevant terms) before laser headlamps become mainstream.

 

[Hilldweller]

Modular LED projector headlamps exist already. Hella makes several of them, as does JW Speaker. These two are OK. ....

The appeal to my community is the longevity and low power draw.
I think they're sexy too.

 

[Colinsdad]

So, as an alternative to HIDs, what would members believe would be the best LED alternative?

As an aside, there's only two vehicles I've owned where the main/secondary (e.g.fog lights) were MORE than adequate for my lighting needs, and those were/are my current vehicle (07 Subaru XT Sport), which has Osrams excellent 5000k H1 bulbs w/HIRs for my brights. The second would be my 04 SVT Focus Euro edition (HIDs primary 4500k temp w/HIRs brights. The fogs were upgraded 893 bulbs-55w). Both of those cars were outfitted with products from Daniel Stern Lighting. ..a bit more expensive for those products, but, you are also getting a personalized recommendation from Dan as well. Worth every penny, especially where I live where streetlights are few and far between.

 

[-Virgil-]

So, as an alternative to HIDs, what would members believe would be the best LED alternative?

Not possible to answer this question helpfully without knowing exactly what lamps/what vehicles you're working on.

there's only two vehicles I've owned where the main/secondary (e.g.fog lights) were MORE than adequate for my lighting needs

I'm not following you here. What does "main/secondary" mean? Fog lamps are auxiliary lamps, and they are not genuinely useful in most cases for most drivers. They definitely cannot substitute for headlamps unless you are truly just c-r-a-w-ling along at less than 25 mph in very bad weather (and in some states even then it's not legal to run fogs without headlamps).

Osrams excellent 5000k H1 bulbs

There is no such thing as an "excellent 5000K H1 bulb". An H1 bulb advertised as producing light of 5000K will have blue glass, and therefore is giving you very much less light than you would have with a bulb that has clear glass. Remember, elevated kelvin numbers in a halogen bulb do not help you see better -- quite the opposite, in fact. The same is true with HID, but for different reasons.

my 04 SVT Focus Euro edition fogs were upgraded 893 bulbs-55w

This "upgrade" is a very majorly bad idea. It does not make the fog lamps useful, it makes them safety hazards.

Both of those cars were outfitted with products from Daniel Stern Lighting. ..a bit more expensive for those products, but, you are also getting a personalized recommendation from Dan as well. Worth every penny, especially where I live where streetlights are few and far between.

I agree Stern takes a very knowledge-driven personal interest in individual upgrade projects, but I have some trouble believing he sold or recommended putting any kind of an "upgrade bulb" swap such as your 55w 893s into fog lamps like the ones on your Focus. In fact, that's something I've seen/heard him caution against doing.