Seems that the arms race of LED tech is slowing down in last 18 months.
Has the technology got nearly as good as it can?
Bike Forum
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Are we reaching the limit of LED brightness?
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Posted 1 year ago #
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I'd say it's still very much in its infancy. There are some big design issues to crack yet - the primary one being efficiency. Sure they are more efficient than filament lamps but LED's are still only 10% efficient which means 90% percent of the power you put in is turned into heat and not light.
The big change currently is the move towards larger die. About 5 years ago, the best LEDs such as Luxeon K2 all used a 1mm square die. The high performace stuff nowadays like Luminus SST90's use a much larger 9 square mm die. Interestingly the lumens per emitting area hasn't really increased that much but now the emmiting area is much bigger. As I said before though, the big issue is heat dissipation. The hotter the LED gets, the less light it emits.
This is know as 'droop' in the industry and it affects all LEDs but the red, red/orange and amber devices suffer most. Typically, if you drive an amber LED such that its junction temperature is 100 deg C, you will only see 25% of the light you would get if you could somehow manage to drive the LED to maintain a Tjc of 25 deg C.
I could go on and on...........
Posted 1 year ago # -
Nah, I doubt it.
Having gone through a fair few lights in the last 5/6 years I imagine clarity etc will continue to evolve. Particularly when we have got the likes of troutie challenging the big brands ...
Proper dark this week around Malvern and I had forgotten how astonishingly good my lights were allowing me to night ride much, much faster than I go during daylight hours (albeit with HiD) 1850lumens from Trailtech MR16.Posted 1 year ago # -
I hope so
Let's have a little dark on our night rides?
Posted 1 year ago # -
stoatsbrother +1
I guess the two areas I'd like to see improvements in are price, and battery technology (the output to weight ratio)
TBH I don't think we need further advances in actual light power. At the Gorrick last weekend the power output on the majority of rider's bikes was astounding compared to a few years back. I just don't see that we need more light.
Posted 1 year ago # -
I just don't see that we need more light.
I remember someone saying something similar about suspension travel.
Posted 1 year ago # -
True; but in those terms we're already riding the equivalent of 10" front and rear on sub 25lb bikes with the lights we have now.
If we can do 10" f&r and get the weight down further OK, but I don't think bikes are going to improve with 15" each end
Posted 1 year ago # -
All my bikes have zero travel each end and my off road lights consist of a single helmet mounted lumicycle Nimh 2000 lampholder modified with a single 200 lumen LED. Personally, I find its more than adequate. Until I ride with someone who has a much more powerful light then it feels like I'm riding in shadow.
Posted 1 year ago # -
All my bikes have zero travel each end
Using solid tyres then?
Posted 1 year ago # -
Ahhh, pedant-tastic STW - marvelous. I would rephrase but you know what I meant. Or perhaps you didn't?
Posted 1 year ago # -
Isn't it just the normal cycle of development - exactly the same as suspension in fact - for years travel got bigger now the focus is on quality fo travel.
LED's have got brighter but now I'm guessing the focus will be on quality of light and function rather than just sticking more lumens in. Thats kind of where the guys like Luminous and Trout are ahead in my opinion as they have started with a product that is conceived to give good light and good run times and engineered it to also be very bright.Posted 1 year ago # -
Lense design is also very import. It would be good to see more light available with different lenses option depending on how and were you were going to use your lights
Posted 1 year ago # -
Lense design is also very import. It would be good to see more light available with different lenses option depending on how and were you were going to use your lights
Posted 1 year ago # -
When the market is right Quantum dot micro-LEDs will take over - their efficiencies blow current led techs out of the water - 85%
BUT I suspect manufacturers won't start dripping the tech in for 5+ years.Yes i did say 85% efficiency - The same quantum (Non-Radiative) Energy Transfer will also be applied to photovoltaic cells - they will be revolutionary.
"700lm from AA battery running for ten hours charged by a solar panel on my bald spot. I have seen the future"
Posted 1 year ago # -
stoatsbrother +2
Quite frankly find it a bit boring when someone sticks daylight in front of me on a night ride. Much prefer the fun and feeling of a more limited vision on a night ride. But I know some people don't night ride for the sake of night riding, they do it because they can't get out in the day.
Posted 1 year ago # -
I just don't see that we need more light.
I don't care about more light, I'd love to have longer runtimes and have fewer batteries to lug around.
Posted 1 year ago # -
Aidy "I don't care about more light, I'd love to have longer runtimes and have fewer batteries to lug around. "
Big big +1 for that, the P7s took us to a point where "more than enough light" is easily accessible but smaller units and better lifespan/smaller batteries will always be worthwhile even when more light isn't neccesarily desirable.
Posted 1 year ago # -
fwiw: there is only one E in Lens.
HTH
Posted 1 year ago # -
I imagine clarity etc will continue to evolve.
what does that mean ? Light has brightness, colour and directivity. Clarity is more a consequence of conditions and the distribution of light. There's a limit to what can be achieved from what is effectively a point source, unless perhaps one were to use some kind of holographic projection...
I've read a lot of people saying colour matters, like using yellow tinted glasses to see better, but I'm hugely sceptical that this is anything other than delusion and suggestibility.
Posted 1 year ago # -
I think when Troutie comes up with something that is actually brighter than the sun, and melts little pug dogs, someone will have to have a word. I suspect that day won't be too far off now....
Posted 1 year ago # -
"All my bikes have zero travel each end ... a single 200 lumen LED. Personally, I find its more than adequate."
There you are see. If you had suspension you'd be going faster and would need better lights.
No disrespect to Troutie, but isn't he just buying in components and connecting them up with some fancy circuitry and nice CNC machining.
I would expect any future big improvements to come from the LED manufacturers, not the light manufacturers.Stuey, what do you mean "When the market is right..."
If 85% efficient Quantum dot micro-LEDs are available now, why are they not being sold ?Posted 1 year ago # -
700lm from AA battery running for ten hours charged by a solar panel on my bald spot. I have seen the future
Solar panel technology - that has a loooong way to go yet as well!
Graham - I think he meant that the QD_LED technology isn't yet mature enough and will need to be properly productionised before it can be marketed. Given that QD-LED is being heavily developed for displays etc it will be another leap that would give us QD-LED to use as a light source for biking. From what I've seen anyway.
Edit - found this
http://www.qdvision.com/quantum-light-platformSeems like they might be getting close - but not there yet.
Posted 1 year ago # -
LED's have got brighter but now I'm guessing the focus will be on quality of light and function rather than just sticking more lumens in. Thats kind of where the guys like Luminous and Trout are ahead in my opinion as they have started with a product that is conceived to give good light and good run times and engineered it to also be very bright.
Very perceptive of you, and I agree. I am of the opinion that at the moment, riding with between 1500 to 2000 lumens should be adequate for all types, and we achieve that kind of performance now with current, productionized, LED tech.
However, its not just a lumen count-fest, as most here realise.
Instead, we can now turn our attention to harnessing the light for desired results.This is where testing comes in, testing combinations of LEDs and optics, along with logic controlled, multi-level output electronics and battery options, in order to create a desireable light system.
Some of my goals are to reduce weight, increase runtime, and maintain a useful level of light.
In fact, I was discussing this plan with Trout a few weeks ago, and told him I was going to introduce an " Enduro " version of the 601.
This version will actually have the output wound back a bit, in favour of an extended runtime from a lighter battery.
The prototype is on my workbench now, about to undergo runtime testing.
I think Trout now offers an "Endurance" option too, seemingly deciding to use a larger battery.Its good to see different approaches to a common goal.
So yes, perhaps we have peaked on the Lumen / Lux count.
As Trout has pointed out, when we double up the lights attached to our handle bars, ie, 2 x 601s, we don't necessarily get double the result.So now the focus turns from how much light we can actually squeeze from a light design, to matters of light temperature, beam pattern, runtime, etc.
As we know, lights have lots going on, and anyone who is insane enough to try to hand-make and sell lights, has to try to keep quite a few plates spinning.
Not to mention offering a quality product.
I was very surpirzed to see the innards, or lack of them, during a strip-down of an Ay-Up light recently, by Trout, while again, he brought another light upto date / back to life.
Surprized also, to see the mode of failure.
.I've recently had a Lupine Wilma 4 in for repair, and thought the quality could have been better, for a £400 light, especiallly when you consider that lights such as the 601 can match it on the quality of the housing, sealing, finish, and exceeded it on quality of other components.
And for all those who discuss the "too much light" scenario.
Most current lights can be dimmed, which only goes to satisfy the need by some people to ride with less light, and to extend runtime, again.Which is all good stuff.
Posted 1 year ago # -
I see a lot of research being done in both industry and academia. Mostly on the glues and adhesives rather than the light output etc. (that's mostly because I work with the chemicals though) but people still care and are still lokng for improvement.
Cost, quality of light and energy consumption could all be improved. I imagine the manufacturers are looking to break the household market with a cheaper product than currently available. I also imagine they are looking at very high powered lights for more industrial and heavy duty applicatios like vehicle headlights.
While I don't want 6000lm lights the trickle down to lower levels would offer advantages in run time, weight etc.
Posted 1 year ago # -
Yes, work continues on improving LED performance, I for one would like to see LEDs produce less heat for a given output.
As the LED companies will continue to press for more lumens per die, we might take those advances to a) reduce the number of LEDs in a bike light, b) to reduce the physical size of a light, as newer LEDs produce more lumens and less heat ?.
Posted 1 year ago # -
There was the same arms race with camera manufacturers as well, trying to squeeze more and more mega-pixels in before finally settling with making the rest of it better.
Same with lights, we know they're plenty bright enough, lets have lighter weight, longer run times, more adjustability/customisation and better weather-proofing.
NiteRider are on the right track with their user-programmable lights.Posted 1 year ago # -
I'm sure it will be the automotive industry that pushes LED's to the next stage in development.
Posted 1 year ago # -
I'm sure it will be the automotive industry that pushes LED's to the next stage in development.
Thats what you'd think, but while there is an appreciable price difference between LEDs and conventional bullbs, the OEMs will make their decision based on cost and homologation requirements.
If all it takes to get your vehicle into a market, is the use of a (cheaper than an LED) bulb, then why go to the expense of using and LED ?.
Thats their thinking for the mainstream car.Lighting efficiency, as well as other advantages that arise from using LEDs won't be at the top of the list of must haves for auto OEMs.
I think the home lighting market presents companies with the kind of business potential that attracts them to invest in LED R&D.
And us MTB'ers will just have to ride the wave of LED advancement
Posted 1 year ago # -
What a thread!!!
The reality is that MTB lighting future is acombination of so many factors, and the stark diversity of customer requests (needs/wants) to the direction of lighting companies is ever changing
LED technology will have another big change in around 3-6 months when the new cree's will start to get produced. In the mean-time, battery technology is constantly being explored, and is a wonderful avenue to explore.
One thing I know we spent time on, and acheived, was that we don't emit any RF. So for all those that are using GPS units on there bikes, will still maintain acurate readings. This becomes important for adventure races.
Light output is one thing, but so many more factors are constantly being improved on (light spread, heat output, unit weight, RF, custom light outputs, burn time, charge time.....)and the list goes on. It exciting times in the light industry.
Posted 1 year ago # -
A lot said, can't be bothered to read it all.
Just have to say I've yet to see an LED that produces the same quality of light as the first Halogen VistaLites I owned. If the technology advances to produce quality rather than quantity, then great.
Posted 1 year ago # -
AyUpRhino.
It seems that AyUps use only a resistor to limit current to the LEDs, is this correct ?.
Posted 1 year ago # -
Interesting point about the RF and EMC aspects. Technically I would have thought that anyone selling lights should have to have them CE marked and this would ensure compliance with the relevant EMC standard. A resistor is very inefficient compared to a buck/boost type driver but it is very 'quiet' as its a passive component.
I've lost count of the amount of hours spent at the EMC lab trying to get some of these switching drivers to pass.
Posted 1 year ago # -
Colour rendition is the thing for me.
I've not played with an eneormous amount of LED bike lights, but the DX P7 torch I had, despite being very bright had tuly appalling colour rendering, and at speed it was very easy to miss important detail (stuff like roots!), just because it blended in to the background. Riding the same trail with my old halo Lumis or an HID, that detail is seen much easier.
Now my understanding is that an LED outputs light at a specific wavelength (or at least a very tight band), and "white" LED is actually a very cold blue - hence objects with a large red or green content don't show up so well. Within the entertainment industry, we use colour mixing LED systems a lot, and many manufacturers are adding an amber LED into the mix of their RGB fixtures to get a good white, and also allow colour temperature to be matched to other light sources. Combining the existing (blue)white LED emitters with some carefully chosen output amber ones could bring dividends in terms of the quality of light output.
(FWIW my current Hope LED4 is better than the P7 in this respect, but only when on full output. The lower settings still seem to be quite "grey")
Agree they don't need to be any brighter though.
Posted 1 year ago # -
A resistor is very inefficient compared to a buck/boost type driver but it is very 'quiet' as its a passive component.
Not sure about that, I would have thought that the two weren't really comparable.
EDIT:
A driver allows for multi level output and other features, its a control system.
A resistor, well, its just that, doesn't do anything else.
Posted 1 year ago # -
solar panels that work at night?, where do i send my money?
Posted 1 year ago #
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