Motorola has patented a way of keeping your mobile phone charged using only sunlight.

The company was recently issued a patent for an LCD that includes solar cells capable of charging the battery in a mobile phone or other portable device.

The basic premise has been proposed before: a display screen is stacked over one or more solar cells, which are charged by the light passing through the display. But earlier designs allowed a relatively small amount of light to reach the solar cells, resulting in very little power being generated even under the best light conditions, Motorola researchers said in the patent.

To solve this problem, Motorola proposed using either cholesteric liquid crystal or polymer-disbursed liquid crystal in the display, instead of super-twisted nematic liquid crystals. This change in materials eliminates the need for both a reflective screen and polarizer in the LCD screen. As a result, Motorola claims as much as 75 percent of available light is able to reach the solar cells, providing a sufficient amount of power to charge the battery of a mobile device.