Announcement: http://www.bizjournals.com/sanjose/news/2011/10/18/digitaloptics-celluon-come-out-with.html?ana=yfcpcI personally like the tactile feedback, but if you have a customer...Diffractive optics is a specialty at Tessera. I believe it has historically shown up in low-volume/high-value products.
I don't know much about this, but I did see a supposed video on the iPhone 5 and it had a project virtual keyboard. I will try to find the link. I am not trying to hype, it could be a different company patent/invention.