I have an idea, so what do you think?

[Gryloc]

Hello. I had an idea about 2 or so months ago, and I just wonder what others thought about it. I am shure it may have been thought of before, but I dont know. Well, I decided to write about this when reading the post for the new Luxeon portable (pretty much like the Luxeon Flash). I was asking questions about the new emitter, but then I vhanged subject and talked about my ideas:

So is this a 1W or 3W die (with phosphor coating) that is out of the emitter package? Can you power this up to 1000mA in very short periods just llike the Luxeon Flash? I wonder if they are listening to flashlight maker because this does seem rather impractical for flashlights (power flashlights, but not a keychain light). It is interesting though. Does anyone know how to solder it to a board? You need to epoxy the back while soldering it on either side for electrical connection, right? How would you protect this vaunerable light, with a plastic lens? Then it is nearly as bulky as the 1W emitter.

I saw the flash before, and I had mixed feelings. The only thing that I would like to try is a large cluster of these things together. Now wouldnt that be cool? I also thought that you can make a light bulb replacement with these.

Feel free to tell me what you think. Of course I am dreaming, but this idea is pretty realistic if you have the machinery to make it. Ok. Simply make a special hexagonal copper bar and make an array of the luxeon flash or die on it. This is so hard to explain. I made many drawings. Picture a hexagonal copper or aluminum bar, with a Luxeon Flash/Portable emitter on each facet. Each face of the bar would contain about 3 of these next to each other. So the final produce would have 18 of these emitters tightly grouped facing 360 degrees so it can be placed in a specially designed reflector. Of course, there will have to be a way to electrically separate each one. One can use the circuit board material used on the metal core circuit boards (like for a luxeon star) to wrap this hex bar. This way you can electrically connect each to the power source while having little thermal resistance to the heatsink. There will have to be testing to see how the heatsink would hold up, given the bar will be attached to a larger heatsink assembly behind the reflector. A hollow tubt can run through the middle to send water through for extra cooling.

..........____
........./____\
........|0|O|0|
........|0|O|0|
........|0|O|0|
........|_|_|_|
..___/__|_|__\___
.|______________|
.|| || || || || || ||
.|| || || || || || ||
.|| || || || || || ||
-U..U..U..U..U..U..U

-OR-
..........____
........./____\
........|0|O|0|
........|0|O|0|
........|0|O|0|
........|_|_|_|
..___/__|_|__\___
.|......................|
.|______________|
.......| |....| |
.......| |....| |
water/fluid In and out.


This was an idea tha was bugging me for some time. They have the Flash emitters for sale for $1.85 at a quantity of 1! It will cost only $33.30 for the emitters for a single bulb replacement, but that isnt bad. it would also crank out about 432 lumens. You can drive the emitters in a series/parallel combination so you can use it for automotive use (about 13.5V -with a good resistor). You can also add another row (6X4 instead of 6X3) or go with a octagonal bar of copper (with room on each facet at 2mm for a emitter atleast). Then you can have a 8X3 or 8X4 array! Wow. You can have a maximum of about 768 lumens with the 8X4 array. It would cost about $60.00 though. Imagine replacing your halogen bulb in your maglite with this. How about a fog light or low beam light on your car? You will have to consider heat with all this, but I believe it is possible. Imagin if you can use the nice die from the emitter of a normal 1W Luxeon star or a 3W. Imagine the output then! If only I had the time or money...

Sorry if I am changing the subject. I just wanted to express the idea I had for a few months. This isnt too much flashlight related, but where else do you post this?

[cobb]

I think it would be cool to have a keyring thingie that flashes every few seconds with a bright burst. Wonder if this is possible for half a year to full year with coin batteries? I made a small flasher for an LED, used an lm 3909 chip and a few parts. I think a D cell was expected to power it for a few years. It used a capacitor, resistor, led and battery. I think the guts of it was like two zenior diodes and when the cap was charged above a certain amount the voltage was doubles or increased to fire the led.

[Gryloc]

Thanks...

[cobb]

I hope I helped and sorry no one else jumped in.

After re-reading this, sounds like you want to make a "bulb" of many led dies on a thingie that looks like the light fixture in a light house with the revolving reflector/prism array.

Next to cooling, I think the next biggest problem would be coming up with a reflector to make that a nice spot light.

I dont know why, but you never hear about using multiple watter style leds. Just use of multiple little 5 and 3 led bulbs. Maybe they are too difficult to focus, disapate heat or just mount, wire and solder?

Ive thought a surefire a2 with 3 5 watt leds vs the 3 plain old leds would be a nice light.

The few multiled high wattage lights or heads I have seen use small individule reflectors for each die.

Then you got the matching of color of those too.

[billw]

Are you sure you can get luxeon Flash in small quantities? the Future site
says $1.85 in 1+ quantities, but it also says the package size is a full reel...

Aside from that, I think heatsinking will be a real problem. A good part of
the science and engineering of a luxeon emitter or star is about providing
a way to get the heat from the die AWAY while still being able to make
electrical contacts, and that's what's missing from the flash; it's just a bare
die with a minimal SMT package. Getting good thermal conductivity to a
bare copper rod is going to be quite a feat.

[Gryloc]

Hi. Thanks for replying so soon. Sorry I never replied as quickly to you though. I have been so busy lately. I understand that heat is an issue. If I can only find a way to show the picture I created of my idea. This shows so much more detail than that simple drawing I made up in my earlier post with symbols and text.

I think that it would be wise to create a slug like pictured above that consists of two halves. When machining these two halves, a ribbed channel can be cut out that is shaped like an upside-down U. When you attach the two halves together, you will have a sort of H shaped tunnel that passes through the slug and behind the Luxeon dies. Early prototypes can us the luxeon flash, but later, better designed aluminum slugs (similarly found in the Luxeon emitter) with a die and phosphor coating placed on the top can be used. This way the heat can be properly transferred to the large copper heatsink and the fluid that flows whithin. The fluid is then pumped to a large copper heatsink that is cooled with a fan. This external heatsink is housed near the headlight assembly and away from any warm parts of the engine. This is similar how the liquid cooling systems for CPUs in computers work.

I have a feeling that this couldnt be used in a large flashlight like I thought due to the complexity and size of the cooling system. This would have to be used as a low beam or a fog light in a car/truck or motorcycle. I am sure that a reflector can be made for this that will give the beam the proper characteristics for driving with. A headlight isnt a tight spot, it is partially spread out and it is fanned to cover most of the road while having some sidespill also. The array of emitters is a lot smaller than you think, also. If you can picture that the array is 7mm high and placed on a octagonal slug that has a diameter of about 10mm, the beam shouldnt be too spread out.

Now driving this would be a breeze. A simple driver that can handle 2.8A @ 10.8V from a 12.5 to 14.5V source voltage from the car battery and alternator can be obtained easily. The driver also doesnt have to be extremely efficient. Imagine when two of these things are oporating properly. You have either 48 emitters (8X3 each module) or 64 emitters (8X4 each module). So you will have either about 1440 lumens with two of the 8X3 modules or 1920 with two of the 8X4 modules. I am sure that you can even use the Luxeon III or possibly K2 emitters (I doubt that any time soon) once you solve any heat transfer issues. Imagine the range of brightness of 3360 lumens to 4480 lumens with two of these modules with brighter emitters! Halogen would be history then. HID watch out...

Now Future Electronics I think is selling the luxeon flash in low quantities. If you look at the Luxeon I or III emitter, they have a "Pkg Qty of 1" and the package type is "1 reel", too. You can buy one Luxeon I or III emitter at a time, so why not the Luxeon Flash? Bin matching shouldnt be too hard. As long as they are the same brightness and forward voltage, the overall beam should look good. The color should be close and similar, but I dont think that it should have to be exact. The color of one emitter shouldnt stand out too much in the beam.

Given the price and complexity of this idea, I understand how this side-emitting light bulb replacement module is impractical, but I think that this would be an interesting concept for small and compact front end lighting systems for future automobiles. If anyone would know how to post a picture on here directly, or they can do it for me, please tell me. I have the .bmp file and I dont know what to do with it. Just so you know, I spent plenty of time on this and I actually drew this pixel by pixel with PSP 8. My hand is far more steady with creating this digitally. I show in this picture multiple views of this module, so I left out few details (except dimentions which I will figure out later).

[Robban]

I have the .bmp file and I dont know what to do with it. Just so you know, I spent plenty of time on this and I actually drew this pixel by pixel with PSP 8. My hand is far more steady with creating this digitally. I show in this picture multiple views of this module, so I left out few details (except dimentions which I will figure out later).

Mail it to me and I'll host it for you:
spam |at| theintarweb |dot| net

[Robban]

Here is the image that Gryloc made:

[Gryloc]

Thanks Robban for the help. I am new to posting pictures obviously. Well, there it is! I see now it can use more work. It may be a few days till I add to or change the drawing. It isnt exactly to the right scale I want, either. The whole module is too small for now, and the emitters could be places slightly closer together (especially if different and smaller ones are used). A friend and I was brainstorming and we thought if this was to be used in an automobile of some sort, then I can use a small radiator and a nice, strong pump. The radiator might be better than creating a special heatsink assembly that the fluid runs through for cooling. Cheaper and possibly more efficient. Consider this will consume approximately 30 watts, so the heat created should not be too extreme. I am mostly concerned about heat transfer between the surface mount LED and the large heatsink slug. I was wondering if Lumileds would be at all interested in a similar concept as this. If they would only create a nicer copper slug that the die was mounted on that you can use without any bulky plastic lenses and emitter housing.

I also thought about the Hi/Lo beam issues (though slightly brighter emitters from a good Luxeon I or III would have to be used for the correct brightness of the Hi beam). Stock halogen bulbs have two filiments that are positioned at two different positions to change the beam pattern. I saw how HID lighting overcame this issue. Their HID bulb actually was attached to a motor or actuator of some sort to move it in and out to change the beam characteristics. The Luxeon module can simply light half of the emitters that are further away from the reflector for the low beam then they all light up for the hi beam, or possibly a certain portion of them can be lit that are facing one side of the reflector that is designed for a wide or narrow beam. Also, if you want, the whole headlight system can be dimmed part way for when it is at idle or in park so save on battery or emitter life, or when full brightness isnt desired. Any other ideas or issues that need to be brought up? Well, please express any feelings of this. I want to know how practical this idea is and if it has any future chances of ever being applied. Thanks!

[andrewwynn]

I did a test with 4x 3W emittesr that fit on a similar but smaller structure that would go into PR base.. but the problem quickly became how to work out a reflector that makes a nice focus.. I'm guessing that you'd need a reflector on the order of 7-9" diameter to get this mega-led bulb to work..

somebody came up with a super-cooling solution using heat-pipe up the middle of a cooling fin stack to achieve cooling simliar to water cooling w/o the water.. in this example.. you could have water just cool the base and have the heat-pipe up into the center, which would simplify the design i think.

The main problem with a solution like this is the luminous flux density is way too low for what you are aiming to achieve.. It's why incan and HID are here to stay for the forseeable future.. you could make a very nice light for a bike... but let's do some simple math..

18x 3W emittesr = 54W.. at high drive.. LEDs are about 20-25lumen/Watt.. so about 1000-1400L.. that's about the light from a 100W incan bulb (house).. from a hotwire incan bulb.. 3000-4000 is more typical of 100W.. and the flux density is faaaar greater because all that light comes from a tiny filament.

It's really neat forward thinking.. and would be superb in a flat-array with many optics/reflectors to make a brilliant flood light.. or a soft spot for a lower-output highly reliable yard light or somethign where you don't need the punch for distance like in a car headlight.

Keep thinking outside the box.. many of the ideas i've come up with were great to start with and i found something making them not practical.. not to say this design wouldn't turn out to be practical, but it's leaning that way from the tests and calculations i've played with myself.

-awr

[ViReN]

Best way is to use Single Star LED and put an Micro Fibre Optic Light Transfer Techineque to make it fit and work in good reflector. (true, it will be at most 3-10 watts) but with a large enough reflector it will be still worth

	 |||      <----Optical Despenser
	  |        <----Optical Pipe
	  |
	+++
	======== <--- Star
_______________
    ||        ||              <--- PR Base