Artículos de Marzo 2016

Self-Adjustable Glasses for the Third World

Jueves, 3 Marzo 2016

To Western eyes, Joshua Silver’s round-lensed glasses may make him look a little owlish, but in developing countries where optometrists and prescription lenses are rare, they could be a sight for a million, maybe even a billion, sore eyes.

Silver, 54, an atomic physicist at Oxford University in England, has invented a pair of spectacles a user can adjust him or herself according to the type of vision correction needed, thus eliminating the need for eye examinations and lens-grinding.

“In America you take for granted getting glasses in drug stores and shopping malls, sometimes within an hour,” says Silver. “But that is hardly the case in the developing world.”

Brings Life Into Focus

Within two minutes, a wearer of Silver’s glasses can bring each eye into focus on near or distant objects, by adding or subtracting the amount of silicon oil held in a thin reservoir sandwiched between the plastic lenses. Once focused, the user cuts off the oil supply and the glasses are set for seeing.

These adjustable specs can help about 90 percent of the population needing vision correction, he says.

But while many eye-care experts and the British government support Silver’s effort, some say getting his product to the developing world at a reasonable cost will not be easy. Others worry his glasses may actually increase the chance of debilitating eye diseases, such as river blindness, since the wearers would require fewer examinations.

Vision Without Need for Professionals

Silver started his own company, called Adaptive Eyecare in 1996 to manufacture and market the glasses. With them, he says, residents of remote villages would not have to travel to regional hospitals or clinics for glasses if a distribution system was set up. The glasses could provide vision correction for near- and far-sightedness at plus or minus six diopters — a wide range of lens curvature for vision correction.

Before his glasses became available, other Third World approaches included distributing second-hand glasses. But sorting through the lenses, giving them out and providing examinations still required significant manpower, explains Silver.

For the past four years, he and a team have performed field tests of his glasses in South Africa and Ghana with some 300 people, with funding from the British government’s Department of International Development and other sources. A trained person gave eye exams to the locals and explained to the users how the glasses work.

“People are capable of setting their own power of the lens with reasonable accuracy,” Silver says. Next, his company is planning a trial of a few hundred people to monitor how they work over a period of time.