Free-track IR 2 DOF?

[Blackdog_kt]

Originally Posted by albx

it's dangerous for long exposure because you can't see it, it's different with the visible light that the eye will protect itself closing... don't say things that you can't prove for sure.. and you know exactly the IRled's wavelenght you are using? Can you measure it or just read the specs the manufacturer say?

You could be right about the fact that the retina doesn't close to protect against non-visible light, i didn't think about that. On the other hand, all IR wavelengths are still below visible light energies. You don't need manufacturer specs to tell you that, IR is on the lower end of the spectrum according to elementary physics. If it's a higher energy, it's not IR anymore but something else

To be perfectly accurate we would need to calculate the intensity and volume of the radiation and not just the energy, but like others have said it's obvious that the kind of LEDs used in head-tracking devices are low powered compared to other applications.