Built-In Solar Cells In Future Smartphone Screens

A researcher named Arman Ahnood has succeeded in squeezing a few photovoltaic (solar power) cells behind the smartphone’s display. He has researched that only 36% of the light generated by an OLED display is thrown off whereas the rest of the light is simply wasted as scattered light or from the boundaries of the display. Ahnood using his logic has created photovoltaic cells which are lined at the back and sides of OLED screens thus using free energy to power the battery. The shape of the cells is almost like OLED and LCD displays and so the main thing is to join this thin film to the stack of other films finally creating OLED screens capable of recycling the waste light. Ahnoond’s thin film also captures dim light as the OLED and LCD’s are not totally opaque.


Galaxy Nexus With Built-In Photo Voltaic Cell


An AMOLED Display's Thin Film Stack

Currently the system includes a supercapacitor and circuitry having an efficiency of only 11% which is much lower than other commercial photovoltaics. But the fact to note here is that though the efficiency is low, the output is free energy which is really good. For a 3.7 inch smartphone screen, the output generated by this system is only 5 milliwatts but as mentioned before, free energy though less in quanitity is better than nothing. Ahnood and his team at London Centre for Nano technology wil have to now experiment with all kinds of designs and materials so as to get the efficiency of the current system to 90% which could  indeed increase the battery life of a mobile by another few hours. Using the power of technology, other energy harvesting techniques can be used which could make smartphone’s batteries to extend a day that too on a single charge.

Source: IEEE.org