LED Headlights

dyyys1

Enlightened
Joined
May 29, 2006
Messages
245
Location
Atlanta, GA
I'm sure many of you guys have heard that the Audi R8 and the Lexus LS Hybrid will have LED headlights when they come out in 2008. I'm curious who here would want LED's lighting up the road and who would stick with incan. The issues LED's have with throw and piercing smoke or fog are well known on CPF. On the other hand, of course, LED's don't burn out and aren't destroyed as easily on impact. If you could choose, what would it be?
 

Flight_Deck

Enlightened
Joined
Feb 18, 2006
Messages
299
I'd take LED over incan, but I'd take HID over LED. It's pretty hard to compete with over 3000 lumens from a single 35W HID bulb.
 

GreySave

Enlightened
Joined
Jun 13, 2006
Messages
686
Location
Erie, PA
After 25+ years in the automotive profession I woiuld chose incan. Two main reasons.


First, many of the HID lamps are just plain annoying. The blue glare, especially from improperly aimed lamps can be outright dangerous to approaching drivers who are blinded by the lamps. If a better quality lamp is used (less blue tint) and headlamps are required to be checked for aim at least once per year,,,,I would change my mind due to the improvement in illumination they provide their owners. Until then, they are as much of a problem as they are a help.

As for LED lamps....Not in my climate unless there is a system in place to heat the glass and melt snow. Otherwise, in our climate, the headlamps would become completely covered by snow rendering them useless to the driver and making the vehicle invisible to other motorists. I am strongly against LED tail lamps for the same reason. We often receive heavy wet snow that will completely cover an unheated LED tail lamp assembly (or even all incan lights if the foolish owner has not turned any lights on). I have seen this numerous times and they are a rear end collision waiting to happen.

I have gone as far as to discuss this with representative from NHTSA, and they agree it is an issue. But until it becomes a "problem" (Which I would assume means that people start being killed in collisions due to lack of visibillity) they will not address the issue.

I know my thoughts may run counter to a lot of what we discuss here. I generally support the use of LEDs where possible and practical. Here though, my automotive background keeps telling me this is not yet a good idea. In time perhaps, but not now.
 

Crashking

Newly Enlightened
Joined
May 14, 2006
Messages
49
Location
Orlando, FL
The led lights on the R8 are only being used for daytime running light purposes. the duty of actually lighting the road up is left to HID projectors. the leds are lined up along the bottom of the headlight housing.

Also the Audi S6 will have a set of 10 (5 on each side) (10 to coincide with the 10 cylinder engine) within the lower grill for daylight lighting purposes.

However the Audi S8 incorporates leds into a reflector type housing along with the HID headlight housing for daylight lighting purposes.


LED technology is not at the point (as we know it) yet where they can be used solely for lighting at night

once led's can throw for long distances, pierce fog/smoke, and have good color quality would i actually want them as headlights... and we as flasholics would be happy as well
 
Last edited:

hizzo3

Newly Enlightened
Joined
Feb 27, 2006
Messages
163
well i hear that hids have a major problem with scatter in fog.....
 

deks

Newly Enlightened
Joined
Jan 30, 2007
Messages
3
Audi is now saying that at the end of '07, their headlights on the R8 will be all LED. From Audiworld:

The task of providing light is tackled in an entirely different way to conventional headlights. A total of 22 ultra-high-performance light-emitting diodes are arranged in seven groups of two or four, performing the various tasks of the low-beam and high-beam headlights.

For the low-beam headlights, the light from the two groups of four LEDs is distributed by two free-form reflectors as a source of basic lighting. In combination with the projection system of the three groups of two LEDs, the design resembles that of an open pine cone.

They provide the range and the asymmetry. This is achieved first by concentrating their lumens via a primary optical device, then distributing it via a new type of plastic lens. The high beam is operated by the two internal reflector shells each with a group of four LEDs.

 

Gryloc

Enlightened
Joined
Jan 20, 2006
Messages
596
Location
Cincinnati, Ohio & North Lewisburg, Ohio
Few ever consider the great possible future of LED headlights. The nice thing about LEDs is that they are ever improving and the headlight can be optically engineered to produce the common beam pattern that we are so used to. Brighter and brighter LEDs are being produced. Single die LEDs can produce 200 lumens of light and multiple die LEDs can produce up to 1000 lumens now (Osram's new LED). I bet by the end of this decade, they will get something right with a form of LED headlights. I wouldn't be so negative yet. It is a new technology that is improving. It will have problems early on.

I am working (ever so slowly) on LED headlights for a friend. I am so busy with classwork that I haven't finished, but from what I seen so far, LEDs can be used solely for lighting at night. I am looking forward to my next project where I will make another set of headlights for another friend. It will use today's technology and use less LED emitters, as well as better optics. I know it is not DOT certified (I heard all of that, lets not bring that up here), but it is competitive with the brightness with most headlights today.

As for places with poor weather, they can always implement already used technologies to melt ice and snow. I live in Ohio so I understand that happens. They can use the same type of heating elements that are used in side mirrors or rear windows to take care of snow and ice. As for taillights, I do not see why they do not use incandescents for normal parking lights (on all the time), then use LEDs for the brighter and more instant brake lights. A combo of LEDs and light bulbs can be used for both modes of taillights, too.

What is worse, when a select few have a little snow blocking their taillights to block the light during winter months, or when what seems like 20% of everyone driving has a burned out taillight(s) all year round? Going to school in Cincinnati (like most cities), you will find so many cars with burned out headlights and taillights that it bothers me (and in some cases, frightens me). If they are not burned out, then they are installed improperly or are aging and grow dim. I always hate the white taillights when the red lens is broken and white light exits the back.

I really do not want to argue with someone with so much experience in the field, but if automakers do it right, LEDs can make some great headlights and taillights. They can engineer headlights correctly and use warmer colored white LEDs and they can avoid glare that occurs with some HID headlights.


-Tony
 

GreySave

Enlightened
Joined
Jun 13, 2006
Messages
686
Location
Erie, PA
<< but if automakers do it right, LEDs can make some great headlights and taillights. They can engineer headlights correctly and use warmer colored white LEDs and they can avoid glare that occurs with some HID headlights >>


Great comments Tony, and exactly to my point. LEDs certainly do have a promising future and there are places in the automobile where they can be used right now. Interior lighting is a good example. I simply hope that a good dose of common sense will be used in the design of future applications of all exterior lighting. A surprising number of today's incan headlamps provide very poor illumination due to style over substance. I used to own such a vehicle and hated driving it at night.
 

dyyys1

Enlightened
Joined
May 29, 2006
Messages
245
Location
Atlanta, GA
My only hesitations are color rendition and, as I said above, piercing fog/snow. Assuming the tint of the LEDs could be improved enought to resolve the problem, I have would love to have LED headlights.
 

raythompson

Newly Enlightened
Joined
Nov 14, 2005
Messages
108
I would prefer bulbs. Simply for the reason that replacements are everywhere if you should have a lamp fail. If an LED light fails you will be hard pressed to find a replacement. You can talk about LED longevity all you want but I have wire bulbs in my Ford F-150 that are now 7 years old and get used quite a bit. Current bulbs are in cars, with the exception of high brightness (Silverstar for example), are very long lasting so I think that longevity is a non-issue.

Wired bulbs do fail of course. Led lights will fail. I would prefer to have the cheaper replacement.
 

adnj

Enlightened
Joined
Aug 13, 2006
Messages
699
The reason that OEMs will switch to LEDs is to improve:
. Vehicle packaging flexibility
. Styling flexibility
. Vehicle aerordynamics
. Vehicle power budget
. OEM warranty costs
. Resistance to voltage surges

Clearing snow can be done with thermal elements (front and rear) or headlamp wipers (required in some euro markets).

Although it is easy and cheap to replace a bulb, the majority of bulb failures occur before the end of the first year in service and are VERY expensive to replace at part cost plus $95/hr to the OEM. It also shows up as a fault on the JD Powers survey.
 
Last edited:

chris_m

Enlightened
Joined
Oct 25, 2006
Messages
383
Location
England
raythompson said:
Wired bulbs do fail of course. Led lights will fail. I would prefer to have the cheaper replacement.
You're comparing apples and oranges. Wired bulbs fail all the time. With LEDs you'd be unlucky if in your whole lifetime one failed on not only your car, but anybody else you know's car. Replacement is simply a non-issue. It's a bit like suggesting you'd rather have the more easily replaceable steering wheel for when that breaks.
 

2xTrinity

Flashlight Enthusiast
Joined
Dec 10, 2006
Messages
2,386
Location
California
raythompson said:
I would prefer bulbs. Simply for the reason that replacements are everywhere if you should have a lamp fail. If an LED light fails you will be hard pressed to find a replacement. You can talk about LED longevity all you want but I have wire bulbs in my Ford F-150 that are now 7 years old and get used quite a bit. Current bulbs are in cars, with the exception of high brightness (Silverstar for example), are very long lasting so I think that longevity is a non-issue.

Wired bulbs do fail of course. Led lights will fail. I would prefer to have the cheaper replacement.
This is actually a good argument for standard potted LEDs that would be swappable -- I always think it's such a waste to replace entire fixtures just because one LED goes bad, similar to how it's necessary to replace an entire monitor with millions of pixels becuase one is stuck.

As for the issue of color temp, the problem with the LEDs is that the color temp is usually 6000K plus on most of the models out there now. This means a lot of blue output which is prone to being scattered. The same is true of 6000K+ HID bulbs that people use for cosmetics. Most of those I see coming down the road are horrible at illuminating things, and produce the most glare for other drivers. Designing the lights (LED or HID) to run at more like 3500-4000K will prodce much more useable light -- for one thing, more of the output is going to be in the green/yellow portion of the spectrum, which the eyes are more sensitive to, and which won't be scattered as much. The best HID lights I see appear to be more like 4000k (more like a neutral light than a distinctive blue or yellow tint) produce less glare for other drivers, and project a brighter-appearing, more useful illumation on the road surface.

With multi-emitter LEDs, they have options to do exotic things as well like a warm/cool combination -- and boost the relative power of the "warm" leds in the case of fog.
 

hizzo3

Newly Enlightened
Joined
Feb 27, 2006
Messages
163
Well a while back newbie posted a patent held by cree on a multicolored dice that had 4 layers.... red, blue, green, uv which should really put leds into the forward and household lighting arena... Once i am done with my tail light on my bike, i plan to try an make a cree driving patterned lamp...
 

2xTrinity

Flashlight Enthusiast
Joined
Dec 10, 2006
Messages
2,386
Location
California
hizzo3 said:
Well a while back newbie posted a patent held by cree on a multicolored dice that had 4 layers.... red, blue, green, uv which should really put leds into the forward and household lighting arena... Once i am done with my tail light on my bike, i plan to try an make a cree driving patterned lamp...
Either that or line thousdands of those emitters into a matrix and make a ridiculously bright jumbotron screen out of it... with little optics on each one it might be visible from space :D
 

Xzn

Newly Enlightened
Joined
Nov 12, 2005
Messages
177
Location
Santa Clara, CA
Regarding the whole glare thing, many cars on the market now use them in projectors (that projects a clean "cut" beam) and they autoaim every time the car starts. Lexus is a maker off the top of my head that uses those.
 

jtr1962

Flashaholic
Joined
Nov 22, 2003
Messages
7,506
Location
Flushing, NY
I'd take LED over incan, but I'd take HID over LED. It's pretty hard to compete with over 3000 lumens from a single 35W HID bulb.
They don't need to. A row of 20 LEDs across the entire front of the vehicle, each with the 200 or so lumens per emitter now possible, can do the same job. More importantly, the light distribution pattern would be better optimized for the intended purpose. Since it would be a bunch of less bright sources, as opposed to two very bright sources, glare would be less of a problem. And you get build in redundency. If one emitter fails, you only use 5% of your light output as opposed to 50% when an HID or incandescent fails. Finally, it's just my opinion, but I feel a design like this would be more aesthetically pleasing.
 

Crashking

Newly Enlightened
Joined
May 14, 2006
Messages
49
Location
Orlando, FL
Regarding the whole glare thing, many cars on the market now use them in projectors (that projects a clean "cut" beam) and they autoaim every time the car starts. Lexus is a maker off the top of my head that uses those.

most of the higher end class of cars have the adaptive headlights
 
Top