High-tech eyeglasses change from near-sighted

A new type of eyewear can move the focus from a distance to a nearby object, allowing the elderly to see things more clearly. The product will soon replace existing bifocals, and overcome other vision problems.

This eyewear will move the focus from afar to near objects, and can replace bifocals in the next 2-3 years.( Photo: Discovery )

The product, called a modified photoelectron diffraction lens, is the work of researchers at the University of Arizona in Tucson and the Georgia Institute of Technology, USA.

According to the researchers, 93% of people over 45 years old need some kind of old glasses to overcome presbyopia. In this situation, the lens of the eye becomes less elastic, so the ability to increase the curvature to focus the light gradually decreases. People with presbyopia can see distant objects, but glasses must be used if you want to see objects nearby.

Bifocal glasses are a familiar solution, but it also means that the field of view is split in half. Another solution is called monovision, using contact lenses for one eye to look far and one eye close. Over time, the brain will learn to use the eye in accordance with the task. Both methods are not ideal and can cause nausea or dizziness.

The new glass uses a small charge to create a precise focus of light on the entire glass. " Users can observe things with the entire field of view of the lens, " said Gouqiang Li, assistant professor of research at the University of Arizona, who led the study.

The glass consists of a thin layer of liquid crystals - the same material for making computer screens - sandwiched between two glass panels. Each glass plate is coated with a transparent electrode layer made of indium tin oxide, and on a sheet coated with an etched layer to create a series of concentric circles.

Light passing through the glass will be diffracted and obstructed by concentric rings and the direction of movement of molecules in the liquid crystal layer.

When a voltage is applied to the electrode to change the direction of the molecules, one will get another focus. Adjust this voltage to get the desired focus.

Currently the new glass model is controlled between turning on and off.

" The difficulty of this particular technology is that it still creates a view or all - or nothing. Users tap a switch and it will shift the focus from far to near. It doesn't make them possible. while looking at the distance and looking closely, "said Mark Bullimore, assistant professor at Optometry University in Ohio.

A company that has bought patents to commercialize this technology, may be born in the next 2-3 years.

T. An