Researchers at the University of Southampton have developed a new kind of nano-glass memory storage that stores data in glass lenses that can read with light. It works a little something like this: Lasers can be used to etch nano-voxels (volumetric or 3D pixels) onto the glass storage disk. This etching alters the way light beams through the lens and the resulting light patterns can be read much in the same way optical fibers are.
One of the main innovations here is scale. When you think of pixels on your screen, they're tiny, but you can still see them if you look closely enough, even if you have to zoom in a little bit. These laser-engraved voxels, on the other hand, are molecular in size. The plains at which the voxels are embedded can be measured in tens of nanometers, or in layman's terms, crazy thin plains. Naturally, this makes for ultra-compact data storage.