FreeTrack Forum

Hi guys,

The easiest way for me to buy IR LEDs is via a webshop which offers the following IR LEDs:

Color: white/translucent
Diameter: 5mm
Wavelength: 850nm
Angle: 60deg. (30deg. from the centerline)
Voltage: 1.8V
DC Power 100%: 20mA

Color: light blue
Diameter: 5mm
Wavelength: 850nm
Angle: 60deg. (30deg. from the centerline)
Voltage: 1.8V
DC Power 100%: 20mA

They also offer exactly the same LEDs with wavelengths of 880nm and 940nm. The longer the wavelengths, the cheaper they are.

Now the question to you people, will either one of these LEDs work?

PS: I'll be using a Logitech S5500 cam with the IR filter still installed and a visible light filter (using an old floppy disk) mounted directly in front of the lens. I aimed the remote control at the cam and it spotted the IR LED just fine. However, I don't know the specifics of the LED inside my remote control.

Ehh.. bump!?

The main point of using IR LED's is that you can block out all other light and the still see the IR light.  Other color LED's let out some IR but not as much as the real IR LED's.  The goal is to make the camera only see 3 points of light and nothing else.  With your current setup, if the camera can see the remote IR, it should be okay, but the IR light should be nice, bright and consistent.  If not, you may need to remove that IR filter.  Another thing I noticed is that the power specs of those LED's you named seem a little low, and the angle too shallow.  You need ones that are at least 150-160 degrees, or file them down so the tip is flat.  There is a specific LED the manual recomends, those are the best and you can get a boat-load shipped to you for a reasonable price, albeit a bit hard to find.  I don't remember the number, but I am sure you can find it in the manual or on the forum somewhere.

EDIT: here they are: http://www.seeedstudio.com/depot/original-osram-ir-led-sfh485p-p-69.html

This is the very same site I got it from, and they are pretty fast at delivering.  (paypal, too)

Note: the most important thing about these LED's is that the convention is opposite of the norm:  The shorter leg is the positive and the longer negative.  I'm almost positive that's the case, but double check to make sure.