Building a Homemade LED system

Hey y'all. I've done a little tinkering with some LED stuff in the past, and I'm thinking about building an LED flashlight/lantern.

My initial idea is to use somewhere between 6 and 12 (maybe more) 10,000mCd power white LEDs. The power input would be 6 or 9 volts (from D-Cells.) The purpose of the project would be to create a portable "light panel" for situations that require ambient lighting, not focused (flashlight) lighting.

Another idea I was tossing around was a "LED Torch." Basically a long (6 D-Cells) flashlight with a half-cylinderical array of LEDs at the top. This is another system for giving off more ambient light then focused light.

To save time, I've been using P-Spice/Orcad to figure out the power and voltages for the planned devices.

My question is this- does anyone have reccomendations as far as places to buy ultra-bright LEDs? The ones I've found were around 10,000mCd for about $1.60 each. The brighter the better!

Thanks,
ALPHA

unfortunately, i dont know where to get the ultrabright non-luxeon led's.

however, i could suggest another--and possibly simpler--possibility: a luxeon star 5w.

i know that the whites arent really out yet...but i have a cyan that i have been toying with. it is scary bright! heck, im only slightly overdriving it.

a single 5w with a clear or frosted cap (no optics) would light a dark room nicely.

then again, it sure is fun experimenting with multiple led's!

good luck,
Bob

i would recommend a couple 1w's. they are very bright, and without the optics, you have a huge degree beam! also, you will actually be paying less if you get the luxeons. be sure to heatsink them though.

Do you guys have the web sites for the items of which you speak? ;-)

Thanks,
Alpha

www.luxeon.com

www.lumileds.com

Thanks! I was looking at http://www.superbrightleds.com/ for high-intensity LEDs. I saw white ones listed for 10 Candlepower for about $1.70 each, which looks like a pretty good deal.

that is a pretty good deal.

keep in mind however, that luxeons are about are about as bright as around 15 of those!

luxeons are available from www.futureelectronics.com if you call instead of buying offline, you will pay less (around $8 i think)

if you compare the prices for the output, the luxeon will seem like a steal.

The ratings on those 10Cd LEd's is deceptive. You won't get a good area light from them. They use the same die and have the same energy output as the lower rated onces, whats different is that they focus the light into a smaller beam and therefore it registers brighter. But if you want to build an area light then they wont work very well.

I agree completely that luxeons are the way to go. You can use the same simple circutry to run them as the regular LED's, however you can get a lot more out of them using a constant current power supply. You can find out TONS about such driver systems by searching around here Should keep you up for weeks at least! There are many home brew designs around as well as several good commercial ones available for decent prices now.

In addition to ordering from future you can get luxeons from http://www.markhannahsurplus.com/ as well as from arc flashlight http://www.arcflashlight.com/

My only problem with Luxeons is that I feel like a second class citizen when dealing when them. What they make available to us is what the big clients didn't want. LED's with less than optimal output and less tham perfect color. While I can understand the business decisions that make them do that, I still feel that if I were willing to pay what the big boys do that I should be able to get their best stuff too. If you can swallow that then a luxeon will replace 10 to 15 of the brightest 5mm LED's and do so for less current. Thouh you will need to attach them to something to heat sink, it's not too bad if you're running them at spec current. They will handle MUCH more current, like 3 times or more, if properly heat sunk (sinked?) and put out a great deal of light. Without the collimator to create a beam, a couple of luxeons epoxied to a good piece of aluminum or some other heat sink would make a very good area light. Side emitters might make a better choice for a lantern, as the name suggests the light comes out the sides

http://www.paulflannery.com
£1.00 per LED in quantities!
I use this supplier for my cyan LED's but he does supply white as well for a similar price!
By LED torch you mean an LED candle, ie an area light on the end of a pole. Lumileds do some nice "bulbs" which would be ready-made LED arrays with an omnidirectional output. If you could arrange for a battery tube containing enough cells to produce 12V (quite easy to do with a 4 or 6D torch body and some of Elektrolumens' battery cages.)
Its then a simple matter to modding the business end of the torch body to take your chosen LED "bulb". The DecorLED bulbs are available in 12V and look just like a regular household mains bulb. They use less than a watt and would happily run off a battery supply for quite a few hours. The bulb is made from polycarbonate and practically unbreakable in normal use! This would look really cool on the end of a portable hand light!