How would I go about building an IR illuminator?

[Calundronius]

I'm getting my hands on a nice sony camcorder with IR ability. The built-in illuminator gives a range of about 10ft, the $70 illuminator sony sells gives a range of about 100ft. Any decent illuminator I saw out there on the web costs much over $100, which is a bit rich for my blood (having just bought a camcorder).
Is it feasable to built an illuminator of my own? Anyone know anything about this?

 

[Heisenberg]

You might try a simple IR LED. Those are what are in remote controls. It would be easy to build a circuit to power one. I'm not sure what kind of range you would get with one though. FWIW

 

[dejitaru]

I see IR LED's sold in bulk often on ebay. They even have nice IR illuminators at good prices.

An array of IR LED's would function quite well. Don't go Radio Shack - high prices
There is also the option of an incandescent IR source.

 

[Calundronius]

I'd think an incandescent IR bulb would be brighter than an LED bay, but I'm not 100% sure. Also, if anyone knows where I can find a site that sells individual bulbs, that would be nice.

 

[cookj]

The IR leds i`ve used only has 20-30 ft usefull range. I have a couple factory ones and a homemade ratshack one,not much difference. The IR lens over a good light sorce works great.

 

[dejitaru]

Either way, it's like trying to illuminate the night sky with a flashlight.

 

[Evadman]

Jameco sells an IR iluminator kit for soemthing like $20. It had a good 50 IR LED's. I remember seeing it in one of my catalogs from them. They are online at jameco.com

<edit>
Found it. ir kit it has 36 LED's. Looks like you would need a difuser of some sort as the beam is only a meter wide at 8m distant.

 

[Calundronius]

Originally posted by: cookj
The IR leds i`ve used only has 20-30 ft usefull range. I have a couple factory ones and a homemade ratshack one,not much difference. The IR lens over a good light sorce works great.

IR lens, eh? I didn't think of that. Do you have any specific lens (or maybe just a filter?) in mind?

 

[cookj]

I bought mine at a gun show. It`s about 4 inches in diameter, glass , with a rubber ring around it. I haven`t looked for any more, mabey a search on military surplus IR?