A group of researchers from MIT have developed a new version of the parallax barrier technology used by Nintendo to give the 3DS its signature 3D visuals. The new version of the screen, called HR3D ("High Rank 3D"), can produce the same glasses-free 3D images as the 3DS, but does so while generating a brighter image and using less battery power. HR3D uses two layered screens to produce 3D, just like the 3DS.
However, unlike the console, the top screen creates a custom image based on the bottom projection instead of processing it in large chunks. Basically, instead of only letting the bottom screen show through in a few vertical lines, this lets the bottom screen show through in thousands of places positioned around what's being shown on the bottom screen. Because of this, the HR3D screen lets a larger amount of light pass through, making it lighter, and uses less battery power while doing so.
Since HR3D is still in testing, it's unlikely you'll be seeing the screen in the inevitable Lite version of the console. For now, the team is working on finding ways to make the screen less taxing on a computer's memory, which would be essential if were going to be used for handheld console. [CNET]