Is this kind of led ok.
I am going to build a ftir table.
here’s a link to the place were I found them.

Osram SFH4350

Thank you verry much

I’m confused - in the spec sheet it says:
“Type 3mm Infrared
Colour Red”

What does the “Red” indicate? Maybe it means infrared but just make sure that you aren’t getting Red LEDs…

rbedi100

I’m sure its an infra red led you can see it in the data sheets.

Thanks for the reaction.

Compared to the “ideal IR LED” by cerupcat and a few others - scroll down on this page - http://nuigroup.com/forums/viewthread/2694/P0/ - its half-angle seems to be on the low side. The minimum half angle should be at least +/- 48 degrees, but your LEDs are +/- 13 degrees according to the data sheet. “Anything less than +/- 48 will not take full advantage of TIR”.

hope this helps
rbedi100

Yes this has helped a lot.
Thank you.
Choosing the lets seems the most difficult part of it all.

and by the way exuse me for my bad English.