Motorola to release phone with no bezel by end of year.
androidpolice.com
androidpolice.com
I think this is more about avoiding Apple's design patents. I'm pretty sure that a rectangular bezel was one of them.
First, you could put the piezo film (commonly used in speakers for cellphones, more efficient for smaller transducers but requires a special amplifier) directly below (but in contact with) the display and use the display as the 'diaphragm'. Makes the entire display a speaker, but would require some interesting sound cancelling tricks to avoid feedback with the microphone.
Second, you could use a piezo below the display with an airgap and use something akin to the laser used in the power LEDs on the Macbooks to poke enough airholes to direct the sound toward the ear.
A third method, which I'm not sure would work, is to suspend the piezo material between two ITO layers (like that used in the capacitive touchscreen) and put it above the display. Depends on if someone has found a transparent piezoelectric material yet; I haven't been keeping up with the materials science side of things.
PS: Also picked this (https://www.youtube.com/watch?v=HU2nG9qy6vs) up from http://forums.whirlpool.net.au/archive/1921701
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