Quote:
Originally Posted by jusmee
Just curious as to how that works. I have heard of resistive and capacitive systems on modern devices, but never a light based system since very early days when they shone beams of light in a grid over old CRT monitors.
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Look around the edge of your screen - there's a very thin shiny strip between the case and the screen itself. That's sending an infrared beam across the top of the screen both horizontally and vertically, and being caught on the other side. When you 'tap', the sensors within the beam projector/receiver register the x,y coordinate of where the break in the beam occurrs, and depending on those coords, and whether it was a single break or a moving break (ie, swipe), the device performs the appropriate action.
It has nothing whatsoever to do with actually tapping the screen, nor how hard you tap, all you have to do is break the infrared beam.
I don't know for sure, but my best guess is that the problem with non-responsive 'taps' is probably due to the sensitivity setting of the beam-break sensors. They have to be set to some threshold above a single (or small number of) pixel(s) of the beam breaking, otherwise bits of dust or fluff sitting on your screen would cause havoc. So if you 'tap' lightly, and have relatively hard skin or pointy fingertips, the 'footprint' of where you finger tap breaks the beam could be small enough and the beam-break sensitivity set large enough that the sensors don't see this as a 'tap'. That's probably why swipes work better. And some kinds of lighting surely will lessen the sensitivity of the infrared sensors too.
That's my guess. If I'm correct, I wish they would include a 'tap sensor sensitivity' setting in the user prefs that we could adjust ourselves to suit our own needs.
Cheers
The REAL Joe