Apple may be going green in the next few years, based on the latest patents given to the company, which reveal solar cells may soon be in all of Apple’s devices.

Apple appears to be creating a new device that can let natural light in and absorb the energy via solar cells in the devices. The key component in the patent is Smart Glass, or electrochromic glass. Acting like sunglasses, the glass can fluctuate its translucency to filter in light.

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The idea is to have a layer of photovoltaic cells – cells found in solar panels that absorb energy – located behind the LCD screen on the back of the device to work with the Smart Glass. Since the Smart Glass can sense when natural light is present and filter more light in, the solar cells would absorb more energy when needed and available. This gives new meaning to the term “smart device.”

Apple was also granted a patent for rear-facing touch controls, a design made with a game-user in mind. These new controls would be on the back of the iPad or iPhone, where your hand curves and your fingers rest. For those who use either device for playing games, the controls would feel more like a real game controller.

The patents revealed one last secret: Apple may be experimenting with cellular connected devices, like a laptop running on a cellular network. As Apple continues celebrating thirty years of Macs, it seems that is hasn't stopped planning for more innovations.

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