Nanoleaf?
Is it true that this bulb can run 1600LM @ 12W without heatsinking?! a guy even says you can grab it with your hands at anytime and it will not burn…
I think there are 33 LEDs total per bulb. Which is around 48.5Lm per LED. Did anyone try to take this apart to use a LEDs for flaslight before?
Another thing they claim is 4000k temperature!!!
There are also 1800Lm versions if you donate more.
If you donate 1000$ you get the world’s most efficient led bulb which is probably 2000lm? o.o
LED is very efficient at low wattage but not at high wattage. To generate 1600 lumens with a single LED is quite inefficient relatively, thus more current and a lot of heat are produced. But with each LED produces only 48.5 lumens I think there is very little heat produced, this also depends on how good/efficient of the LEDs they use.
So I think:
1 LED to produce 1600 lumens - inefficient, lots of heat to handle.
33 LEDs to produce 1600 lumens - efficient, and I believe it is feasible even without proper heatsinking.
Looks like cheap generic 1 watt LEDs though…
Maybe they have a rather good efficiency at low power, but 0.5 Watts is not exactly very low, if these are indeed the cheaper LEDs they look like….
It seems like 80% of kickstarter projects are junk. Overpriced “revolutionary” designs that are actually already available, junk that is all marketing or straight up scams.
There certainly are a few great kickstarters projects.
So does it look like it’s PCB material with emitters on it, or does it look like the large panels are say large aluminum substrate “stars”
Seriously. it looks like OSHPark boards cut in geometric shapes to give that lightbulb shape, there is more than enough room inside to house the electronics to push the constant current to the emitters
Lightbulb shaped dodecahedron
If these were so revolutionary why aren’t they on the market, seriously it looks as if we could easily whip up a few boards at OSHPark with ample enough vias to wick the heat away from the emitters to the back side of the board (the back would be the ground plane/heat sink strata) and run some of these inexpensive 1W LED’s (just have to get a driver to safely convert mains to the required voltage for the emitters) They might not be cheap though…the SRK boards are $13-$15~ a pop for a set of 3
Unless that is some sort of very inexpensive aluminum star dodecahedron the OSHPark boards should be able to handle the heat, unless you REALLY push the emitters hard
The driver is the hard part…due to the safety of isolating the mains from the body of the bulb (has anyone seen the driver board in these cheap LED lights yet…not alot to em, but doing it safely is paramount)
Definitely looks like the Bead-style LED emitter either the copies or which is basically the Lighting-class Luxeon (i believe the KR or Star series ?)
> http://www.electronicamagnabit.com/tienda/621-984-thickbox/luxeon-star-power-led-3w-blanco-.jpg
> http://letsmakerobots.com/files/field_primary_image/Luxeon_007.jpg?
which are available in 1-Watt and 3-Watt configurations. (3W has a larger phosphor & die area) These are available in Warm White 3200 K, Neutral White 4500K, and cool white 6000K tints. I have bought all variations of these in packs of 50, and implanted them in many of my modded LED lanterns in my lantern collection. I found when testing the 1W version it can produce roughly 90 to 100 lumens with 170 - 200 ma without generating much heat and surviving not mounted on any star ( just free standing) Their Wide-emitting angle makes them my favourite for lantern Mods. Some of the lanterns in my line-up photo in my Steam Pipe Light Topic uses these LEDs.
Looks like salvaged PC boards from a Radio Shack science kit, and bases salvaged from old glass Incans. i like to see one of these in action along side the New Phillips & Cree Household LED bulbs to compare output, wattage load, heat, etc.
Cereal_killer said a 4 pack is like $125 bucks…I would bet that even the high cost of the boards from OSHPark we could get a complete set of 3x of these for roughly $45…5 pack of 1W emitters is $.99 at fasttech and a AC>DC 6-10 led driver from fasttech is roughly $2 (it would fit inside the PCB dodecahedron), now just to find a supply of the A27 male threaded posts and voila…4 for $45 and some DIY
sure…it’s a whole lot more expensive than buying those already made Chinese ones with the flat plate 10-15 emitter designs w/ frosted plastic lens, but this is a DIY tinkerer’s kinda project
The kickstarter price would be unfair to compare against. That price is to fund a project. People got pretty excited back then even with that crazy price, even here iirc. The Cree bulbs weren't around back then either. The current price on their website is too much though. I'll go ahead and accept their efficiency claims because if they're still making sales anywhere the Cree bulb is sold, it's to people that need the highest efficiency. It's only a couple watts and some heat, but I suppose that could matter to people in very small homes and limited (solar?) power.
I was one those that got exited about it…then I learned how to make OSHPark boards. Honestly it wouldn’t be that hard to make em “open source”
The biggest cost will be the PCB’s and I think with ample via’s under the emitters leading to a back side ground plane/heatsink would greatly increase heat dissipation
Just need some uber geometry guru to come up with a design for the lightbulb dodecahedron assembly
Oshpark pcb's would be cheap, no doubt. As you said, the driver is the hard part. The one you found on Fasttech doesn't have nearly enough power.
I think back then I mentioned that I'd love to get into lightbulb modding. I don't think the geometry would be too difficult if you're serious about it. It's just pentagons, except the bottom ones have a longer edge. So a set of six identical pcb's, and another set of five identical pcbs would make up the body.
I'd like to see a tiny fan fit inside of it...mostly just because it'd be cool, even if it doesn't have much effect.
Heat is something that you cannot get around. What counts is not the total power per device, but the power per unit area of device and ultimately, the temperature of the junction. That in turn is determined by the heat sinks in use.
If you make the die large enough, a single LED could produce 1600 lumens with comparable efficiency. No matter how large or how small the device is, you need to have someway to get rid of the heat, the more heat you dissipate, the bigger the problem. In small devices this is often done with simple convection cooling, That doesn’t work very well in small confined spaces, and you cannot really get rid of a lot of heat that way unless the device gets really hot. You don’t think 12 watts is much? Leave a 10-watt incandescent on for a few hours, and try to unscrew it with your bare hands.
Ultimately It really doesn’t make any difference whether you have to dissipate 12 watts in a single LED, or 33 LED’s. Let me assure you that there are plenty of devices that easily fried at 360 milliwatts. You still have to get rid of 12 watts.
A 10W incandescent could be very hot after tuned on for a few hours, because those incandescent bulbs have very poor efficiency thus most of the electrical energy were converted into heat energy instead of light.
33 LEDs are so much more efficient than a single LED alone, thus much lesser heat were produced under the same power. A single XM-L2 can produce 1600 lumens, but it needs to be pushed really hard and since it is not efficient to do so a lot of heat is produced. On the other hand a single MT-G2 (having a larger die size) can produce 1600 lumens much easier than a XM-L2, but at the same time it still produces a significant amount of heat; 33LEDs to produce 1600 lumens? It’s like only 48 lumens per LED which produces so less of heat that we can ignore.
A generic 5mm LED produces about 5 to 10 lumens and you practically don’t need any cooling method at all; A better quality high-power LED is more efficient than those 5mm LEDs, thus operating at 48 lumens is just a piece of cake. Imagine your flashlight switching into low mode (like 5%) and you basically won’t feel any heat produced at all even operated at a prolonged period.
Edit: Even if there is heat produced, I do believe that the heat is little enough for the PCB itself to handle. Let’s just hope the inventors would do a test to convince us to purchase their bulb since they charge so much.
They do test it. In the video, you can see the chamber they test it in (1600+ lumens)
I personally have no care for how much they are selling it for. I am just surpised at how they are able to reach such effiency when my 10W light is burning up my hands.
So those LEDs that are on the board are only a bit better than the cheapo 1W Leds that are in the market right now?
