Another guarantee of life is presbyopia even though it may not have the sting of taxes and death. From the age of 45, this vision defect plagues most people and as the lenses in their eyes lose the elasticity needed to focus on nearby objects. Reading glasses may present remedy for some people and others; they are only fixed, short of surgery, is to wear progressive lenses.

Gordon Wetzstein, Stanford electrical engineer, said that more than a billion people have presbyopia and scientists have created a pair of auto focal lenses that might one day correct their vision far more effectively than traditional glasses. At present, the prototype looks like virtual reality goggles, but the team hopes to streamline later versions.

Auto focals, the prototype glasses of Wetzstein, are intended to solve the main problem with progressive lenses of today. These traditional glasses necessitate someone wearing them to align their head to focus appropriately. It is like driving a car and looking in a side mirror to change lanes. There is little to no peripheral focus with progressive lenses. The driver needs to switch from looking at the road ahead through the top of the glasses, then turn almost 90 degrees to see the nearby mirror through the lower part of the lens.

Also, it is hard to navigate the world with this visual shift. According to graduate student Robert Konrad, a co-author of the study when describing the auto focal glasses published in the journal Science Advances, Konrad said the people wearing progressive lenses have a greater danger of falling and injuring themselves.

The prototype from the Stanford works much like the lens of the eye, with fluid-filled lenses that bulge and thin as the field of vision changes. Also, the prototype includes eye-tracking sensors that triangulate where an individual is looking and determine the precise distance to the object of interest. Not only did these scientists created these lenses or eye-trackers, but they developed the software system that harnesses this eye-tracking data to keep the fluid-filled glasses in constant and perfect focus.

The Stanford team tested the prototype on 56 people with presbyopia to validate its approach. According to the tested subjects, the autofocus lenses performed better and faster at reading and other tasks. Also, the wearers tended to prefer the auto focal glasses to the experience of the progressive lenses, the bulk and weight aside.

Downsizing technology is the next step. As Wetzstein thinks, it may take a few years to develop auto focal glasses that are lightweight, energy efficient, and stylish. He is convinced, however, that the auto focals are the future of vision correction. He concluded that this technology could affect billions of people's lives in a meaningful way that most techno-gadgets never will.