‘FingerShadow’ Saves OLED Power

A paper published by Microsoft Research ( has shown a new way to conserve power on mobile devices.

Recognising that the screen is the most power-hungry component in a smartphone, Microsoft researchers have developed a method called ‘FingerShadow’ to reduce power-draw. Utilising local dimming, the system darkens areas of the screen that are covered by a user’s fingers and thus not visible. It is estimated that the FingerShadow could save between 5% and 22.3% power (averaging 13%), without compromising the user experience.

The researchers suggest that a smartphone screen could be dimmed when a finger is hovered over it, as well. The latest Sony Xperia and Samsung Galaxy smartphones have touch sensors capable of detecting these interactions. As part of the study, a Galaxy S5 had its sensitivity reconfigured to detect a hovering finger, up to 1.5cm above the display.