I just found 2 LED models that I can use to the FTIR and DI units… as some of you should remember, I bought 2 IR illuminators that result on a very bad option to setup the DI box, the beam is so focused that I can’t be able to align them correctly and avoid blind the camera with the hot spot produced by the illuminator.

So, I’m about to built my own custom setup… I just need to be sure about this LED models that I found:

IR333C

Wave length 940 nm
Dir. Voltage 1.3
Max. Voltage 1.7
Power 20 mw
Light angle 27°

IR383

Wave length 940 nm
Dir. Voltage 1.3
Max. Voltage 1.7
Power 20 mw
Light angle 12°

I think, in both cases (FTIR and DI) the choice should be the first one because of the light angle, or the second one could be better for the FTIR because the light could travel longer in the plexi?

Cheers!

I would go with the OSRAM SHF-485P they output at 880nm which is easier for a CCD or CMOS censor to detect 940nm is a bit too high for a lot of cameras, further more they have a an angle of +-40° light angle this is much better for a DI setup… For FTIR you shouldnt go with a beam that is very narrow from my understanding because you need to have the IR beam to bounce withing the top and bottom surfaces of the acrylic if that does not occur FTIR wont occur either… the less the IR refracts within the top and bottom surfaces the dimmer your blobs will be from my understanding but i may be wrong… if i am someone with a better understanding should correct me.

Taha

Taha - 01 July 2008 03:05 AM

I would go with the OSRAM SHF-485P they output at 880nm which is easier for a CCD or CMOS censor to detect 940nm is a bit too high for a lot of cameras, further more they have a an angle of +-40° light angle this is much better for a DI setup… For FTIR you shouldnt go with a beam that is very narrow from my understanding because you need to have the IR beam to bounce withing the top and bottom surfaces of the acrylic if that does not occur FTIR wont occur either… the less the IR refracts within the top and bottom surfaces the dimmer your blobs will be from my understanding but i may be wrong… if i am someone with a better understanding should correct me.

Taha

Thanks Taha, but I´m waiting for a trip I got planned soon to Mexico City and another one to Miami, FL. I hope to find a lot of different models to choose from.

Cheers!