just been granted a rather interesting patent
for an "Electronic device display module," which is really a fancy way of describing a clever dual-sided laptop display with a solar panel on back. The front of the lid would house your typical LCD, though the backside would be constructed from electrochromic glass atop photovoltaic cells and touch sensors. In other words, it's a solar panel.
The idea, of course, is that the lid would pull energy from the sun to charge the laptop and/or offer longer battery life. That's not all Apple has in mind, however. As described in the patent filing, the light energy gathered could be used to illuminate the logo. Apple also envisions the rear of the lid being used for touch input commands like media controls, pass codes, and other uses.
"The rear plate may be formed from electrochromic glass. Photovoltaic cells may be located under the rear plate and may produce power when activated by an external light source. Touch sensors may be located under the rear plate and may gather touch input," Apple explains. "A control unit may be used to process touch commands on the rear plate to perform functions such as unlocking a magnetic latch that holds the upper housing to the lower housing."
Apple's MacBooks are obvious candidates for a patent like this, though Apple says it could also be implemented on tablets, mobile phones, and other handful devices, as well as things like monitors and televisions.