Transparent cellphone screen doubles as solar charger

Discovery News : Cellphone battery life is one of the most limiting aspects of the devices. One possible solution is to include solar cells in the body or screen of the phone. Solar cells on the backs of phones have existed for a while but have never been widely adopted. So now efforts are focused on screens. Some companies are working to develop transparent solar cells that absorb only nonvisible light. Others are working to include solar cells in organic LED screens. Both options are expensive and still experimental. SunPartner Group from Aix-en-Provence, France, has developed a low-cost solution using current technology, which they are already testing with manufacturers. Their screen is made of alternating layers of thin-film solar cells and transparent film. A layer of lenses is added to focus the incoming light and to spread the screen image to hide the solar cell strips. The screen is currently 82% transparent, with future versions expected to reach 90%. The company estimates that adding the screen to a phone will increase the cost by less than $5 while extending battery life by 20%.