On Decreasing Power Consumption of Displays

Given our remit to improve the human-computer interface, we spend a lot of time thinking about displays. Modern displays are pretty good - thin, high resolution and so on – but they use a lot of power. Indeed, in a typical liquid crystal display, less than 6% of rays from the backlight get though the liquid crystal panel. That’s a lot of waste and the result is batteries which are thicker and heavier than we want, and often need recharging.

The mainstream display industry wants to reduce power by changing to organic LEDs which only create light where it is needed. That sounds better than the liquid crystal display which blocks light where it isn’t needed.

So why doesn’t Microsoft just wait for these new displays? Because when you think about it, almost all the light created by a display is wasted. After all, only a tiny fraction of rays end up entering the eye of a viewer. The real waste comes about because each pixel glows like a light bulb, illuminating the whole surround. Much better to work out where all the eyes in a room are, then arrange that each pixel sends rays only to those eyes.

Finding out where are all the eyes in a room is just the kind of thing Microsoft does well - think Xbox Kinect – so although we want organic LEDs, we are also trying to promote displays which concentrate their emission into the viewers’ eyes.