Why is a smartphone like a hummingbird? Neither can go more than a few hours without refueling, or bad things happen. (If you answered that smartphone owners are often forced to flutter around looking for a power outlet, I’ll accept that, too.)Do you know where the power goes? As the graphic shows, around half your battery is spent on the display alone. And of that, the vast majority is used simply to power the backlight that all LCDs need. (The situation for AMOLED displays is similar, but for different reasons. That’s a subject for a future blog.)Clearly, improving the power efficiency of the display is a powerful way to improve battery life. Turning the brightness down isn’t a helpful strategy. Indeed, we expect displays to be brighter and richer all the time, but not at the expense of already limited battery life. (Bigger batteries would also work, but the market has spoken on that one. Slim is in!)How is this to be accomplished? Find out after the jump.