Why are most LED headlamps poorly heatsinked?

[Barbarin]

Taking a look at many LED headlights, some of them even expensive and/or manufactured by reputated firms, seem to have poor thermal designs.

That eventually will lead to premature ageing of emitters, low efficiency...

Obviously there should be reasons for this, at the end they are industrial products made by well known manufacturers. Thinking about it my conclusions are:

1. Realistic usage. Nobody expects that a customer is going to use a headlamp during 20.000-50.000 hours. That is realistic as that using time would mean 10 hours a day during 2000 days, or 6 years, every night, all night long... By that time the problem won't be the LED but the switch, the battery holder, the scratchs on the lens... And probably there will be much better emitters that would make your headlamp to look like a candle attached to your head.

2. Weight. Most headlamps manufacturers are much more interested in keeping the weight as low as possible than in pure performance or total reliability (Weight is very often one of the most important arguments to sell mountain/trekking material). Average density of quality plastics is less than 50% than aluminun alloy.

3. Cost. A plastic injection part cost a fraction of the cost of a machined one.

4. Design freedom. Plastics will allow better shape than machining...


Probably it is a mix of all the reasons above described, and each time on a different percentage what makes headlamps to be be usually poorly designed in terms of thermal properties, and consencuently on efficiency when using high power settings.

It would be nice to know your opinions about this.

Javier

 

[PhantomPhoton]

Why are most LED headlamps poorly heatsinked?

I've been trying to figure this out too. My first thought was simply beleiving that headlamp manufacturers were lethargic. "There isn't much competition, so why take the time to make a better headlamp anyway?"
Now I'm more under the belief that most manufacturers are simply for lack of a better term really dumb. They seem to lack the creative juices or intelligence mojo or something to produce a quality lighting instrument. So we get cheap plastic garbage. They put LEDs into their decades old incan format and call it good.

Therefore we'll have to wait for a couple Chinese companies like Zebralight to completely outclass them first before they'll hire people who make intelligent designs based upon physics.



The bottom line I think is that they can make money on the cheap junk they have right now because there are a ton of uninformed consumers out there who will buy the stuff.

 

[Woods Walker]

Apex.

 

[Barbarin]

Apex.

Thanks for your input. Yes the APEX, seems well designed, as well as some other lights. But they are just a few. The title of the thread says "most" not "all".

Javier

 

[YuccaPatrol]

Another reason may be that the vast majority of headlamps are cheap and most of them are not very bright when compared to our hand held flashlights. It is only recently that a few headlamps have been offered that are bright enough to warrant a significant heatsink. Just a couple years ago, the 60 lumen Apex was the king of the mountain and considered incredibly bright.

 

[Woods Walker]

Thanks for your input. Yes the APEX, seems well designed, as well as some other lights. But they are just a few. The title of the thread says "most" not "all".

Javier

Run time is more important than pure lumens for a headlamp in my view. Often I use a flashlight for under 10 minutes or maybe longer but mostly under an hour. I often use headlamps for 5 plus hours. Lots of headlamps are poor more so for the high output single mode ones I see in B&M. So now with the higher output Cree etc there is a lumen war breaking out in the headlamp market but often they just added a brighter LED and did nothing else. They don't care if the light is done under 1 hour. Only if the lumen rates are higher on the package. This is why someone looking at a 50 lumen Rebel EOS might go for the crap headlamp next to it that says 100 lumens. After all 100 must be better than 50 and who cares if 3XAAA direct drive will give up the ghost in 45 minutes on high only. After all 100 lumens must be better!

 

[Barbarin]

I agree with you booth. 95% of the people who needs a headlamp are going to need it for close tasks, during short time. That is the reason the Tikka is a very good design (exception made of that 3AAA configuration that I personally hate). It is small, light, fits in your smallest pocket, is reliable, and if needed it can work all night long.

For that purpose, as back-up light ,I would choose something like 1AA/1xCR123 and 3/ 4 Nichias CS, as light as possible. No need for multimodes.

But 5% of potential users need a headlamp for rescue, for caving. They need to illuminate far more than their next three steps, they need something in which they can trust under any condition, mud, sand, water, snow, cold, heat, impacts.... In my opinion is a compete different product, and my perception is that some designers are just sticking to the design guidelines you can find on "light" headlamps, doing as much as adding high ouput diodes, that is all.

Javier

 

[PhantomPhoton]

I also agree a majority of headlamp uses don't require driving an LED hard, but I'd think there is a large group of users out there who use headlamps for outdoor activities. While not as extreme as SAR or Caving, general backpacking, biking, night skiing etc. activities need more than a Nichia CS imho. (btw why not a DS or a GS? :tinfoil
It's always good to b ea able to turn up the power for a bit when you're dealing with tricky terrain, a cliff, or other obstacle. I think the outdoor activities crowd is a larger marketshare than 5%.

I think being able to use a cree or SSC power LED at ~50mA for general use and long runtime and being able to kick up to a "medium" power around 500mA is what we need to see more of.
The probem is the idiotic plastic construction for the most part on these lights. Aside from being able to heatsink a power LED properly; most of these lights have failed miserable in the durability and water resistance in my experience.

I absolutely can't stand 3 AAAs (or 3 AA's) either.

 

[Barbarin]

While not as extreme as SAR or Caving, general backpacking, biking, night skiing etc. activities need more than a Nichia CS imho. (btw why not a DS or a GS? :tinfoil

Right, GS better than CS.

I think being able to use a cree or SSC power LED at ~50mA for general use and long runtime and being able to kick up to a "medium" power around 500mA is what we need to see more of.

So in your opinion that two output levels is enough?

The probem is the idiotic plastic construction for the most part on these lights. Aside from being able to heatsink a power LED properly; most of these lights have failed miserable in the durability and water resistance in my experience.

That is the reason I'm starting to think seriously to bring into "real production life" one of my designs/prototypes. Would you all want to help me with this? I have some ideas.


Regards

 

[Unforgiven]

Several posts have been removed in violations of CPF rules. Moderation is not an appropriate topic of discussion. Further violations will result in suspension of posting privileges.

 

[shomie911]

That is the reason I'm starting to think seriously to bring into "real production life" one of my designs/prototypes. Would you all want to help me with this? I have some ideas.

Sure, what do you have in mind?

 

[jch79]

Javier,
I'd love to see a high-quality headlamp from Barbolight! I do really like self-contained battery packs, which probably isn't appropriate for a diving light though. :shrug:
Bring it on!
john

 

[PhantomPhoton]

I've pitched Ideas to a couple manufacturers so far with no luck apparently. I'd love to give you my opinions and design ideas.

For a general use small backpacking light 2 modes may be all that is needed. 3 may be better, depends ob the distribution of light/ beam type and how bright highest output is compared to the low level.
Lots to consider, especially if we want to make something a bit "bigger" than a general use headlamp.

 

[Barbarin]

OK, now I'm going to start a new thread a think tank about the developing of a headlamp. This thread will be kept as it was intended to talk about poor heatsinking on headlamps.

 

[nksmfamjp]

Have you seen the huge heat sink on the Remington? It is seriously like .75" x 1.5" and the CREE LED is mounted right to it. In addition to it's size, it has a good number of fins!

 

[Barbarin]

Have you seen the huge heat sink on the Remington? It is seriously like .75" x 1.5" and the CREE LED is mounted right to it. In addition to it's size, it has a good number of fins!

I have not seen that light, mainly because they are not available in Spain unfortunately.

It seems that Rayovac makes good things, and very well priced.

Is interesting to see how you can find better solutions on headlamps by brands not so known, or even unknown, than from the most famous manufacturers. When it comes to quality, the famous brands are a warranty.

Javier

 

[bhvm]

You can completely excuse the 'cost' reason.

Factory made lights are helluva expensive compared to 'bare stars + driver + cells.'