Apple does seem to be looking at multi-touch/multi-haptic response in screens although their current patent application is using actuators. Toshiba's charged film response is a far more elegant solution of course. I wonder if a good haptic multi-touch screen will finally be enough to bridge the gap and silence complaints over the lack of physical buttons compared to dedicated gaming devices.
They say deposit charge, but I think it's just a electroactive polymer actuator with a transparent polymer.
PS. well I was wrong (although I think a transparent EAP actuator matrix would be a good idea as well). They say they use attraction force though, not electrical stimulation ... so the top surface would probably be an insulator, humidity shouldn't matter.
I wonder if a good haptic multi-touch screen will finally be enough to bridge the gap and silence complaints over the lack of physical buttons compared to dedicated gaming devices.
Actuator solutions really, really suck. In fact they are even worse then no-feedback at all.
I don't know about this Toshiba method, but it's missing the point anyway. Touch was originally rejected by the market ~30 years ago as input device, even though panels were cheaper then buttons of the era. Physical discomfort and complete lack of ergonomic doesn't make it a good alternative to buttons, no matter what feedback you tack on it.
People should be looking for alternatives to typing (and other button based input activities) rather then trying to mimick keys, if they want to replace them.
It's an interesting technology, but it doesn't seem useful for blind button input ... you only get sensation while sliding your finger across it AFAICS. So if you put your finger on it vertically you can't perceive the location of the button, if you use a pressure sensitive resistive touch screen (so you don't have to lift your finger off) you can find the button with it, but while pressing it they can't give feedback when you have pressed hard enough (no click).
That's what you really want, the ability to feel the edges of buttons, pressure sensitivity and tactile feedback when the pressure exceeds the threshold.