So I've got a baby on the way & being the video geek I am, I haven't been satisfied with the quality of my baby monitor's video in pitch black & figured I need to add a secondary IR light source to improve it.

Problem is, all the cheap IR light sources I find are fairly narrowly focused. Usually I'd solve something like this by adding a diffuser of some type but knowing nothing about IR can you soften an IR source? If so, what type of material would work?

I figure other than for my odd little application this type of info could be useful to many people using IR sources for more professional purposes.

Light's light. Put a piece of glass or plastic in front of the LED's and spray it with hairspray until you get the right amount of diffusion. If the LED's are around the lens, put a round piece of tape on the glass where the lens peeks through, spray the glass, then peel the tape away so the lens has a clear spot to look through. The nice thing about hairspray is you can clean it off and try again if you put on too much, plus your wife probably has a can or two already.

Martin

I had just figured the wavelength of IR light might interact differently with traditional diffusion material. If it doesn't then great, good to know.

It --might--. Some plastics that are opaque to visible light will pass IR, as anyone who ever developed IR-sensitive film in a plastic developing tank can attest (stainless steel ONLY). The converse is also true, as a silicon slab is opaque to visible light, but passes IR like, well, glass.

Play around -- hair spray, waxed paper, vaseline. See what works.

Martin

I don't know how widely available they are but down here you can find IR LED kits pretty cheaply that seem very simple to assemble. As you're mounting the LEDs yourself it would be easy enough to leave the leads a little longer and angle the LEDs to give a wider beam.