An Apple patent in the US has shown the company exploring the idea of LCDs with switchable privacy levels. A screen on a device like an iPad, iPod, or Mac would have a "scattering module" behind the screen, as well as wedge-like liquid crystal elements in the screen itself, that would steer the lights going through the display. Toggling a privacy mode on the device would narrow the cone of light so that someone couldn't spy on the screen while still giving the owner a clear view when looking head-on.
