Super screen

Super-bright, large-scale, and very high-resolution digital projectors are becoming indispensable tools of modern communication. They are also very expensive. Prices for high-end projectors run into tens or even hundreds of thousands of pounds, which keeps these devices from being widely used.

But HP Labs' Nelson Chang and Niranjan Damera-Venkata had a hunch they could make a much cheaper projection system by combining the outputs of several smaller projectors to create a single, high-quality image.

As the researchers saw it, only one thing stood in their way: What they were proposing was widely thought to be impossible.

Earlier work seemed to show that you could combine two images to create one higher-definition image only when the images were offset a very small and precise distance from each other. But projectors simply can't reliably throw images onto a screen that precisely - so no one had done it.

What if, the researchers wondered, you could find a way around this and combine two, or indeed 10, very imperfectly aligned projections to create a single, super-bright and super-resolution image?