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RSS >  Infrared LED's, Equivalents
Vic Shaw #1 14/09/2007 - 01h44

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Registered on : 14/09/2007

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What are the equivalents of the SFH485P LED's from other manufacturers?
Can't get the 485s locally.
jbalat #2 14/09/2007 - 04h33

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Registered on : 21/08/2007

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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.

tristan68 #3 14/09/2007 - 09h04

Electronicien en chef
Class : Electronicien en chef
Posts : 651
Registered on : 10/07/2007

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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 :
Posted Image

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
Vic Shaw #4 14/09/2007 - 19h50

Class : Apprenti
Posts : 2
Registered on : 14/09/2007

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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.

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