Hello all, I’m new to the Forum.

My question is : does someone know what’s the maximum width for an FTIR surface ? I guess, beyond a certain distance between two IR ramps there should be a loss in the acrylic internal reflection (guess the thickness and the Leds power comes also in consideration), but I never found an exact information about it.

Thank you very much in advance if you would know…

Thierry

Hi, i’m new here too and also very interested in the question whether or how FTIR is size-limited.
As Jefferson Han points out [1], it should be spatially scalable with the necessary illumintation. However, I could not find any studies covering this issue. So, if anyone knows something about it, would be great help.

[1] “Low-Cost Multi-Touch Sensing through
Frustrated Total Internal Reflection” http://portal.acm.org/citation.cfm?id=1095054