FreeTrack Forum

What are the equivalents of the SFH485P LED's from other manufacturers?
Can't get the 485s locally.

I used 4 of these and they work great. I sanded them lightly as per instructions to diffuse the light. I think they just need to be wide angle. These are 60 deg.

IR EMITTER OP293B:
<http://www.rsaustralia.com/cgi-bin/bv/rswww/searchBrowseAction.do?N=0&Ntk=I18NAll&Ntt=234-0940>

Hello Vic

You can use almost any IR led with a little tweaking, just be sure to get the operating values of your leds from your shop, for proper resistor calculation.


You may have up to 2 things to adjust :

- Your beam angle may be too narrow

the solution here, is to papersand your leds, to have a flat top. This somewhat reduce a bit the lighting strength, but will increase the beam field.
ie :


Here you can see a standard 3mm led i used for tests, and the same led sanded just below.


- Your Led wavelength may be mostly or completely cutoff by the webcam builtin IR filter

In this case , you'll have to unmount this IR filter (I had to,  my "noname" IR leds were simply not seen by the webcam until I removed that filter)


About the OP239B :
These are about 1.2V 100mA IR emitter (890nm wavelength). They are suitable for freetrack.
Use this values to calculate resistor values , or even less current.

When you mount them , be very careful to mount them the correct way, cabling them the wrong way may destroy them , since their rated reverse voltage is only 2V.


Hope this helps

Thanks for the help.
Done some homework and it looks like the defining factor is the wavelength.
The SFH485P is 880nm, nearest I can get locally is 960nm which is closer to white light I think. They are cheap enough to try as an experiment.
Thanks again for help will keep forum informed.