Focusing light through frosted glass leads to new 3D display technology
Ars Technica » Scientific Method 2017-01-30

Enlarge / We're not at the hand-held hologram projector state yet, but we're getting there.
Sometimes it amazes me how fast physics goes from fundamental ideas to producing a new toy. The latest example comes from a bunch of experiments and theory on how opaque materials affect light passing through them, a topic that we have covered extensively in the past. The work had the catnip qualities of being cute and simple and exploring some pretty fundamental physics ideas.
The idea behind the research was simple. Scattering materials, like white paint or sugar cubes, turn light into a chaotic jumble. But if we could control how they scatter light, we could turn them into useful things like focusing devices. I know the researchers who pioneered this idea, and they were all rather conservative about possible applications. And that was appropriate; the ideas that they had—medical imaging, high-resolution imaging, and security applications—have all (with the exception of security) proved to be possible but really difficult.
So I was a bit surprised to see the ideas applied to holographic displays. I have to admit, I never even thought of it, but once you see the idea it is like being slapped silly by Captain Obvious.