Looking for special led light or information on how to build it.

Deer-n-da-headlights

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Sep 23, 2010
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Hello,

I am looking for special led it will be

Shape: Cylinder
Length: 1 - 1.5 inches
diameter: .125 inches or smaller

This is for a prototype for a safety product that I am trying to build. It does not have to use a lot of energy to power it and should be durable enough to be used outside.

I have looked on about 50 to 100 web pages for something it it and have not found what I am looking for.

Also if anyone knows where I might be able to find instructions on how to build one my self and or information on where to get internal parts to build one that would be awesome.

Thank you for any help you can offer!
 

panicmechanic

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:welcome:
Don't think there will be an LED in that shape. Similar projects use acrylic rods where the LED shines into one end and lights up the cylinder.
The LED can sit in a hole or just be glued to the end with transparent glue.
If you need the whole cylinder to shine (probably...), you should experiment with sanding of the surface.
There are also acrylic materials where tiny reflective particles are blended in, so the whole structure shines.
A good address might be companies that make advertising signs, indoor and security lights. Also shop decorators might be a good source.
 

Deer-n-da-headlights

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I do not need a battery that small. I plan to attach these lights to a nylon strap in series the strap will be rolled while the product is not in use as so the lights have to roll up with the strap and hopefully not increase the diameter the rolled up nylon by very much. the power source is connected to the strap and the lights directly.

thank you for your help so far. is no way to build a LED light at home? I mean the actual bulb not a flashlight.

~~~~~~~~~~~~~~~~

the power source is not connected directly to the lights. So I do not need a battery that small.

I plan to attach these lights to a Nylon strap connected in series. The strap will be rolled when it is not in use so by using a light of this shape and size I am hopping to avoid added bulk to the diameter of the roll. The power source will be connected to the strap and held in the storage case where the strap is stored until used.

One other question is there any way to make your own bulbs at home if so what materials do you need and how or where do you get them?
 

Th232

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In short, there's no way to make LEDs at home. There are, however, lots of commercially available emitters that are within your required diameter.

If you're planning on running these at any kind of significant power, you'll also find that you need heatsinking otherwise the LEDs will go :poof:.

How bright do you need these to be? If the answer is "not much", then you might be able to get away with using a string of 5 mm LEDs.
 

MikeAusC

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The smallest LEDs in a rugged case are 3mm diameter - you can get a range of colours.

You can get smaller SMT ones, but these are also very low power.
 

Deer-n-da-headlights

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I find it hard to believe that there is no way to make a LED at home. But then I am not sure what it takes to build one. however there are a lot of things that have been built in the garage that many thought was not possible to do.

you stated that lots of commercially available emitters that are within your required diameter.

where might i find these and who makes them.
 

VegasF6

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As to where to find a 3mm led, pretty much anywhere you would find LED. Radio shack, ebay, electronic wholesalers. Try the link I submitted.

As to making your own led from scratch at home, it is hard to believe that it would be hard to make at home? Really? Well, you will just have to believe us that you can't make your own LED emitter. Perhaps we are misunderstanding what you want though.

Take a read at this, http://members.misty.com/don/ledc.html its an article I was reading recently about what makes the different led colours. (when I explained to a friend of mine recently there really are no true orange leds, he seemed to think they should be able to make them any color imaginable)
 

Th232

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Perhaps, as Vegas said, we're misunderstanding you. Here's a page on how LEDs are made, start about half-way down for the actual process:

http://www.madehow.com/Volume-1/Light-Emitting-Diode-LED.html

Personal commentary from me on each of the steps:
1) Note that the article just says the materials are purified, the required purity level is usually very high, a fair bit above 99%. The pressure chambers are pretty expensive as well.
2) When it says 10 mils thick, that's 10 thousandths of an inch, or about 1/4 mm. Bear in mind that this is a hard, crystalline structure as well, not some plastic that can be sliced up easily. The polishing process is also very fine, I've seen a couple of sources saying an Ra of 1 nanometre was needed. Having looked at microchip dice under a good microscope, I can believe that.
3) This cleaning step (actually, this whole process) is done in a cleanroom, generally one of the higher standard ones. We're getting a lower classed cleanroom at work, and maintenance costs will run in the thousands per month.
4) Note the thickness layer, several microns thick, or at least 15 times thinner than a human hair.
6) Nothing that special here, except that the features are on a very fine level.
5) Not too familiar with this step, but I suspect that if you don't get the right composition and timing you'll stuff up the wafer.
7) Here we're not just melting metal, but vapourising it.
8) A 2 inch round die, 6000 patterns. This is for the commonly available 3 or 5 mm LEDs then, because those dice look like they're under 0.5 mm^2.
9) Eyeballing the gold wires on the LEDs I have here, they're less than the thickness of a hair, so while this process is probably less difficult than the others, it's still on a bit of a fine level.
10) Finding the right encapsulant with the right optical properties is surprisingly hard. While clear Araldite or Devcon 2-ton might work in the short term, efficiency definitely won't be the best.

Is this what you were thinking of doing at home?
 
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Noctilucent

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Making a lightbulb at home isn't that difficult - making one that lasts at high output is a different matter.

Making an LED is a completely different matter altogether.. the material alone isn't exactly something you can pick up at a local hardware store.

panicmechanic is absolutely right.. just take a 3mm LED (available very cheap in bulk) a 1.5mm LED (bit more expensive, but would fit better) or some SMD LEDs (relatively cheaply available, pre-wired, off of e.g. auction sites), buy some acrylic rods of .125inch in diameter, cut down to size, glue LED to/in rod - done.
 
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