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Researchers in the US have discovered how to make electronic screens display sharp images for users with defective eyesight, without their having to wear glasses or contact lenses.
The technology, being developed at Massachusetts Institute of Technology and the University of California, Berkeley, essentially “puts the glasses on the display, rather than on your head”, says Gordon Wetzstein of MIT. “It will not be able to help you see the rest of the world more sharply, but today we spend a huge portion of our time interacting with the digital world.”
Vision-correcting displays are likely to be particularly useful for the millions of people with presbyopia, an inability to focus on nearby images, which becomes worse with age. If you are one of them, think of the joy of seeing a smartphone or laptop screen clearly without glasses.
The researchers showed a prototype based on an Apple iPod this week at Siggraph, the world’s biggest computer graphics conference, in Vancouver. It has a printed screen sandwiched between two clear plastic films, which is peppered with microscopic pinholes that correct the light coming from each of the iPod’s pixels according to the viewer’s optical peculiarities.
This vision-correcting hardware could be used by anyone. The key to the technology is computer software that adjusts the array to suit the individual user’s eyesight.
“Our technique distorts the image so that, when the intended user looks at the screen, the image will appear sharp to that particular viewer,” says Brian Barsky, project leader at UC Berkeley. “But if someone else were to look at the image it would look bad.”
Several years’ more work will be needed to develop the technology to a point at which it can be applied to consumer electronics. The prototype is markedly less bright than the original iPod screen, some resolution is lost and the corrective effect does not work from all viewing angles. But the researchers are confident that these obstacles can be overcome – for example, by eye-tracking technology to adapt to the position of the user’s head.
It may even be possible to extend the image correction from individual to shared viewing, such as a family television, says Fu-Chung Huang, a member of the Berkeley team who now works for Microsoft as a software engineer.
Photograph: Fu-chung Huang