updated 10:45 am EDT, Thu June 19, 2008
Apple PET Touch Patent
Apple has been developing technology that would let it offer inexpensive multi-touch panels made out of plastic, according to a newly-published US patent filing. The company believes it has discovered a way to drop expensive, thicker glass panels by using polyethylene terephthalate (PET) plastic without the drawbacks associated with the format. The invention would put near-transparent, capacitive wires in rows on one panel and link them to columns on another. A resulting multi-touch panel could be made out of the low-cost material without being wider than its glass equivalent, as with existing techniques for plastic that put all the wires on the same panel.
This discovery would also generate less interference from long connectors and would help separate the touch panel from the rest of the components in the system. Apple would have more flexibility in designing touchscreen devices where the touch input is separate from other circuitry in the device, according to the filing.
Submitted just two weeks before the release of the iPhone last year, the patent isn't believed to be in use for the iPhone 3G but could lead to lower-cost iPhone and iPod touch units as well as touch-capable conventional iPods; Apple cites the examples of both a cellphone as well as a portable media player. An example of the latter shows an unusual design which would include a click wheel like the iPod classic and nano but a touch-sensitive display.
The company isn't, however, under obligations to use the technique in any shipping products and hasn't indicated its being close to implementing such a design.