Are most higher end LED's concidered "general purpose", or are they more specialized?

[HighlanderNorth]

Are most higher end LED's concidered "general purpose", or are they more specialized?

I had started a thread a couple weeks ago asking why a few of the other Cree LED's arent used commonly in flashlights, like the XT-E for instance, and I also mentioned one or two others as I recall, and there are more than that out there. Someone seemed to be eluding to the idea that some of these newer Cree LED's(and maybe other brands' LED's as well) are becoming more specialized, so they would be better suited for certain purposes like maybe home lighting, where its important that the beam be spread out instead of focused. But also certain LED's may have tints that are better suited for other applications(unless every LED can be produced in whatever tint bin is needed(?)

When I last looked at Sylvania and GE LED bulbs for home lighting, I didnt see the actual LED brand listed in many of these, so I assume they are made by either Sylvania or GE. Are the LED's used in these "bulbs" specially made for home lighting applications, or are they also used elsewhere for other purposes? I would assume if these bulbs were fitted with Cree LED's it would probably be listed on the package.

With the common flashlight LED's that we see and talk about every day, are these LED's also used in, say office lighting fixtures, or outdoor lighting for around the landscaping by parking lots, or maybe even in home fixtures? How about for replacing the stock bulbs in auto tail lights, etc? I just watched a video where a guy had replaced the sequentially operated tail lights/turn signals in a late 60's Mercury Cougar with LED's and it made them much brighter than with OEM bulbs. Here's the video, these old Cougar sequential turn signals are the coolest, and this compares stock bulbs with new LED's in the tail lights(yes, this is how they operated from the factory in '68). Also fast forward to around 50 seconds. http://www.youtube.com/watch?v=WXswBsQ6fbA

So, are the XP-G, XM-L, SST-90, even XP-E considered universal LED's, or are they best used for limited purposes, and what about the newer LED's and the future LED's, will they tend to be more geared towards special applications instead of being multipurpose?

But also, What else have you used the common flashlight type LED's for, and how did it work out?

 

[idleprocess]

Re: Are most higher end LED's concidered "general purpose", or are they more speciali

LED's that are good for flashlights are not necessarily good for general lighting - the inverse is also true.


Flashlights generally form a beam of some sort, which generally works best with something resembling a point source - regardless of whether you use a reflector or an optic. Color rendition - in spite of the preferences strongly expressed on CPF - is not as important for flashlight as general lighting; something generally acceptable as "white" will work for for the vast majority of the marketplace. Since most flashlights will use one emitter, high output per individual emitter is desired; lights that use multiple emitters will still place a premium on emitter performance since optics need a certain amount of space to do their job. Flashlights also tend to operate for brief periods, so emitter lifespan and thermal design are not quite as important as in general lighting. Finally, flashlights are a small slice of the overall LED market.

In general, higher-performing emitters with tight optical specs tend to go into flashlights. That market will pay a premium for cutting-edge performance and doesn't need long lifespans since most flashlights see a mere tens of hours operation before they are discarded. Even on CPF, I'd be surprised to see flashlights routinely exceeding 1000 hours of operation.


General lighting needs to achieve some sort of control over light distribution, but does not require the tight beamforming of a flashlight. Color rendition is critical in LED general lighting - it is competing with established, cheaper-to-acquire technologies that have excellent color rendition abilities. General lighting will typically use many LED's in an array format of some sort; peak per-emitter output is not important since general lighting has immensely more space to work with. General lighting runs for hours and days at a time, so thermal and operating-life concerns are key. Lastly, general lighting is the lion's share of the LED market.

Mature, lower-performing, extremely durable LED's with looser optical specs and cheaper production costs go into general lighting. Since light fixtures have so much more flexibility on their layout, the LED's can be anything from bleeding-edge screamers suitable for flashlights down to vast arrays of low-power SMD LED's. Cost is a key factor in general lighting since buyers need to balance LED's greater purchase price against better (promised) TCO. LED's in fixed lighting are sort of like how laptop CPU's used to be nearly a generation behind desktop CPU's - it allows the manufacturers to tweak their bleeding-edge products for applications with greater constraints (power in the case of laptop CPU's, longevity and greater thermal tolerance in the case of general-lighting LED's).

 

[bose301s]

Re: Are most higher end LED's concidered "general purpose", or are they more speciali

Not a single one of Cree's LEDs is really focused at flashlights. The focus is general illumination and replacing incan and CFL for lighting. There are LEDs that work great for flashlights, XM-L, XP-G/2, XP-E/2, XR-E and even XT-E and XB-D, however not one of these was designed for a flashlight, they just happen to work.

I interned for a lighting company in 2007, we ended up putting the XR-E in a new desklamp we were designing because in our testing it was the brightest LED out there. The new Insignia 60 and 40 watt bulbs use XT-E LEDs and many others are used in various products.

 

[Norm]

Re: Are most higher end LED's concidered "general purpose", or are they more speciali

This is an illegal modification.

I just watched a video where a guy had replaced the sequentially operated tail lights/turn signals in a late 60's Mercury Cougar with LED's and it made them much brighter than with OEM bulbs. Here's the video, these old Cougar sequential turn signals are the coolest, and this compares stock bulbs with new LED's in the tail lights(yes, this is how they operated from the factory in '68). Also fast forward to around 50 seconds. http://www.youtube.com/watch?v=WXswBsQ6fbA

Norm

Read this post.

I'm starting to wonder why it's so difficult to come up with an LED taillight bulb that's a drop-in equivalent to the incandescent versions.

Because a lamp (taillamp, stop lamp, turn signal, etc.) designed for use with a filament bulb has optics engineered and focused to look at a filament of a particular size, shape, orientation, and position, collect light from it, and distribute that light at the required levels through the required range of angles. If the shape, size, orientation, position, or luminance distribution of the light source changes, all that optical engineering is right out the window. The analogy that comes up again and again (because it's a good one) is putting on somebody else's glasses: no matter how nice they look on your face, you won't see properly because the optics aren't for your eyes.

I found a 3157 style LED that's actually a little brighter than the incandescent equivalent

No, it isn't. Not unless it produces 402 lumens, which it does not -- not immediately, and certainly not with usage that extends beyond a couple of seconds, because none of the LED "bulb retrofits" have anything like adequate thermal management for the emitters.

and it even has full beam coverage like a regular bulb

That may be your subjective impression, but objectively no, it doesn't.

It actually outperformed the incandescent version

That may be your subjective impression, but objectively no, it didn't.

in terms of visibility

Measured how? I'm guessing the answer is "subjectively", which is not a measurement.

and visual crispness.

This does not mean anything; "crispness" is not a quality of light.

I don't get this.

It's fairly easy to understand. The difficulty is that there are a lot of marketers working very hard (for very good pay) to make it seem like an easy, simple, carefree swap. It is not. The problem is with the concept, not with any particular implementation.

 

[RoGuE_StreaK]

Re: Are most higher end LED's concidered "general purpose", or are they more speciali

This is an illegal modification.

Perhaps not; as a 1960s car, design rules may not have actually existed at that time. For example in Australia a car must comply with the relevant design rules at the time of manufacture, eg. a '76 car has to comply with '76 design rules. ADRs didn't become legally binding until 1969, so (in Australia) there are no design rules to comply with, so it would be legal.
http://www.infrastructure.gov.au/roads/motor/design/index.aspx

 

[Norm]

Re: Are most higher end LED's concidered "general purpose", or are they more speciali

Perhaps not; as a 1960s car, design rules may not have actually existed at that time. For example in Australia a car must comply with the relevant design rules at the time of manufacture, eg. a '76 car has to comply with '76 design rules. ADRs didn't become legally binding until 1969, so (in Australia) there are no design rules to comply with, so it would be legal.
http://www.infrastructure.gov.au/roads/motor/design/index.aspx

How many late 60's Mercury Cougars do you see running around the roads in Australia with US plates?
Your post is irrelevant to this case.

I can't find a reference but I' sure I remember US imports with sequential blinkers having to have the lights converted to flash as a single unit here in Australia.

Norm

 

[HighlanderNorth]

Re: Are most higher end LED's concidered "general purpose", or are they more speciali

How many late 60's Mercury Cougars do you see running around the roads in Australia with US plates?
Your post is irrelevant to this case.

I can't find a reference but I' sure I remember US imports with sequential blinkers having to have the lights converted to flash as a single unit here in Australia.

Norm

Well the sequential tail lights in the Mercury Cougar and the earlier Ford Thunderbird were factory stock. The only difference in that video was that they had replaced the incan bulbs, which were ridiculously hard to see, with LED's. Apparently there was actually a mechanical system that controlled the stock sequential tail lights, which was expensive to put into those cars and expensive to fix later. Some Cougars didnt still have their sequential turn signals working correctly when I started noticing them in the 80's. Instead they would just link them together as one unit.

^BTW, I have seen and had a friend who owned a 68 Cougar, and I dont remember the tail lights being as dim as the 'allegedly' OEM ones were on the right rear ones on that Cougar. This apparently was a company's video, so maybe they installed dim lights to make their LED's look that much brighter.

But you are in Australia, if I was there and in the market for a new car, I'd buy the Holden/Vauxhall HSV Maloo R8 Ute. In America, if you said "sport ute", people would think you were referring to a sport utility vehicle like a Ford Explorer, but the Maloo is the equivalent of the old El Camino and Ranchero in America. Its a car/truck. Its a Ute! Its also the fastest stock, factory truck in the world as of 2006, with its GM/Chevy LS 6.3L V-8.

 

[Optical Inferno]

Re: Are most higher end LED's concidered "general purpose", or are they more speciali

Getting back to the main topic as the title suggests... some LEDs are "geared" towards certain applications while others are more generic. Something like the XP series of LEDs are used in many different products (streetlights, EVL lights, flashlights, commercial lighting) while LEDs like the Lumiled Altilon are geared towards automotive forward lighting. Take this idea with a grain of salt though as you can use almost any LED for almost any lighting application with the proper optics and mechanical design.

As for the automotive modification... from what I remember, in North America there is no regulation for exterior lighting on a vehicle if it is earlier than a certain year...and I can't remember what that year is. Also...the old Cougar's aren't the only vehicles with sequential lights like that...the new mustangs have them too. There is a thread in the automotive section discussing the sequential turn signals on the mustangs, and those guys would be able to solve the question about the legality of the Cougar.

 

[Ken_McE]

Re: Are most higher end LED's concidered "general purpose", or are they more speciali

Since light fixtures have so much more flexibility on their layout, the LED's can be...vast arrays of low-power SMD LED's.

Hey, how did you know about my new hall light??:huh2:

And here I thought I had the only one...

 

[idleprocess]

Re: Are most higher end LED's concidered "general purpose", or are they more speciali

Hey, how did you know about my new hall light??:huh2:

And here I thought I had the only one...

Because I briefly had my location set as 127.0.0.1 .