With age, the lenses in our eyes often lose the ability to change shape enough to focus light from near objects onto the retina - a condition called presbyopia. This leaves people who were already short-sighted unable to focus on either near or distant objects. Bifocals offer a solution by having two lenses in the same frame, but users must get used to tilting their head up or down to switch focus.
Zeev Zalevsky at Bar-Ilan University in Ramat Gan, Israel, has developed a technique to turn a standard lens into one that perfectly focuses light from anything between 33 centimetres away and the horizon.
It involves engraving the surface of a standard lens with a grid of 25 near-circular structures each 2 millimetres across and containing two concentric rings. The engraved rings are just a few hundred micrometres wide and a micrometre deep. "The exact number and size of the sets will change from one lens to another," depending on its size and shape, says Zalevsky
The genius is in the simplicity of it, it's a terrific idea.
I'm crazy abusive with my glasses anyhow