From Staska's article:
You know that Apple really cares about the design of its products? Well, that’s probably an understatement. And the new iPhone is a thing of beauty, right?
But there’s this one annoying little thing that prevents Apple to achieve the perfection – a uniform surface slab ideally shaped for your hand… The various components that emit or capture the light. Like camera, proximity/infrared sensors, flash, display. You have to leave those annoying transparent holes for the light to get through. And it must be driving Jony Ive mad.
But maybe not for long. Apple has an idea how to hide every component that is not in use from the surface of your iPhone. It’s called polymer-dispersed liquid crystal (PDLC) window.
PDLC window is a layer that can change its opacity when electric current is applied. It can be color matched to the surface of your device with all light emitting and receiving parts hidden behind it, so there are no annoying sensor holes on your iPhone’s front and back. Then, when you press an icon, PDLC window becomes transparent and camera with flash, or fingerprint sensor shows up where you need them.
If you really want to – even your iPhone’s display can be hidden behind PDLC layer, so the only way you can tell between the front and back of your device is the home button or some other decoration.
Apple is also thinking ahead about the things they could do with PDLC windows when transparent display technology becomes good enough for mainstream gadgets. There will be no need to find extra space to cram a front camera, fingerprint or iris sensor, or even a few solar cells on a body of the device. Just shove them behind the display, put a PDLC window on top and you are done.
Very Star Trek. Or even beyond that - the only surface-transforming gadgets I ever saw in Star Trek were of alien origin...
The current phase of smartphone fashion (2007 to 2012) was arguably* sparked by the original iPhone and Steve Jobs pointing out that with a device that was all screen, the display could mimic any other buttons or controls needed. Perhaps PDLC will be part of the next phase of fashion and design, with devices which are - literally- slabs, out of which display areas, controls and sensors 'appear' when needed?
* of course, full-face touchscreen devices had existed since some of the Palm OS and Windows Mobile devices, and even things like the Nokia 7710...