Cutting Back on Colors for OLED Screens Boosts Cell Phone Battery Life by 40%
a map of the US rendered using both normal colors on the lower half, and energy-minimizing colorson the upper half; Image via OLED Display
Cell phone companies have been looking at the transition to OLED technology for mobile screens in no small part because of the energy-saving possibilities. Samsung has been leading the way with LG and others not far behind. But OLED displays themselves might get an energy makeover through a limitation on the number of colors used on the screen. A power savings of as much as 40% can be seen when using limited colors. According to New Scientist, researchers from Simon Fraser University in British Columbia, Canada found that by choosing a particular balance of colors used to make up an image can show a significant power savings.
Different colors displayed by an OLED pixel use different amounts of energy. For instance, yellow uses less energy than magenta, even when both look equally bright. By designing color sets that cut back on power without really affecting how the display looked, the draw on the battery was cut by between 37% and 41%. As OLED Display explains:
OLEDs can be made even more frugal by carefully choosing the balance of colours used to make up an image. One is based on a set of discrete user-named (categorical) colors, which are analyzed according to their energy consumption. The second is based on the constrained continuous optimization of color energy in the perceptually uniform CIELAB color space.
The researchers note how the information can be use to create different display modes to help extend battery life: "Say you're running low on battery and you want to use Google maps to get home," says [Johnson] Chuang. "Switching to an energy-aware colour set could make your battery last longer."
The new way of displaying colors doesn't equal a perfect image, but a user looking to extend battery life won't be put off by the minimal difference. You can read the publication of the researchers' findings to get additional details of the twist on the technology.
OLED display technology is headed to everything from TVs to laptops. While we'll want most devices to be able to display the full vivid color spectrum for the visual experience, having this kind of energy-saving color mode would be a huge help not only on making mobile device battery charges last, but also extending netbook and notebook battery life while working on the go.