Faces light up behind self-adjustable glasses

Self-adjustable glasses can change the lives of people who have no access to an optician. A Dutch company has made glasses where sliding two lenses over each other gives the variable lens strength.

On a dusty square, deep in the bush in Tanzania, a group of expectant villagers sits under a large tree. They fiddle curiously with the plastic wrapper of a Dutch invention that will change their lives forever: self-adjustable glasses.

This is how Jan in ’t Veld, one of the people who developed the glasses, describes his work in Africa. “I tie an eye test card with figures to the tree, explain the process through an interpreter, and then people adjust the glasses to the right focus with small knobs on the side. I see their faces light up as they discover that suddenly they can read again, distinguish weeds from crop, or separate the teeth-breaking stones from harvested corn. With glasses people can take care of themselves again, work, get an education. They are back in control of their lives.”

There has been great publicity about the British physicist Joshua Silver and his self-adjustable glasses. But In 't Veld's stepson Frederik van Asbeck has been designing adjustable glasses since 2003. Van Asbeck: “Starting this week they can be manufactured in large quantities. Our new machine will produce one million glasses per year, for one euro a piece.” The price is the big difference with Silver's glasses, which can be adjusted by adding or removing fluid from tiny syringes on each arm. In ’t Veld: “His glasses are still in the experimental phase and cost 19 dollars. That is prohibitively expensive in developing countries.”

Proud possession

The glasses Van Asbeck designed, the Focusspec, were tested in Ghana, Tanzania, Cambodia, Afghanistan, India and Nepal. In ’t Veld: “Giving them away for free did not work at all because then people were not economical with them. When we sell them for 3 to 5 dollars, or a maximum of 3 days' wages, then they become a proud possession. We publicise our arrival through posters or local radio. Then people are waiting for us on the village square. Each time we help 100 to 150 people.”

But there are still one billion people who want glasses. Even if they could afford to buy normal glasses, there is no ophthalmologist to test their eyesight. Ben van Noort is an ophthalmologist in the Netherlands and board member of the Focus on Vision foundation, which is developing the Focusspec. He travels to Ghana every year to conduct cataract operations: “They have one ophthalmologist for every 2.5 million people. That is why the distribution of second-hand glasses does not work very well: you always need an expert to find the right glasses for someone. There are some social workers who travel around, but they can only help 20 people a day.”

With the Focusspec the person with poor eyesight does not need an optician. Anyone can adjust the glasses themselves. Van Noort: “Our lens varies from +0.5 to +4.5 diopters or from -1 to -5 diopters. The lenses are very good, but they are a standard model, without cylinders. With them, you can make 90 percent of adults very happy.”

Grey-haired men with reading glasses

The concept dates from 1962, when the physicist Luis Alvarez conceived the idea that by sliding two carefully formed lenses over each other, you could make glasses with variable lens strength. Each lens can vary from concave to convex, and thus the combined lens can vary from minus (concave against concave) to plus (convex against convex). Van Asbeck: “The technique needed to mould these lenses was developed only last year. It resembles the moulding of CDs.”

That is why the inventor Ron Kok was asked to design the glasses-making machine. Twenty years ago, Kok invented a method of mass producing CDs which until then had been expensive products made in a laboratory.

According to Kok, the glasses must be accurate, but also light, easy to wear, look reasonable and be resistant to dust, humidity and strong sunlight. “The invention is conceived in one second, the trouble has only just begun.” He was referring to the difficulties the team had with finding investors.

Kok: “Everyone thought it was a great idea, we were present at the World Economic Forum in Davos and visited other non-governmental organisations. Our mistake was: we had brought a minus-glasses model. These are suitable for children, because they have the greatest problems, according to what the WHO told us. But who is in control of the money? Parents and grey-haired men with reading glasses. They would put the minus-glasses on their nose and say: ‘I don't see anything, it doesn't work’. So we rushed to make a plus-glasses model. That worked better, but it was a struggle to scrape the funding together.”

A luxury problem

The first 30,000 glasses will be shipping to Afghanistan and Tanzania this month. In ’t Veld: “In each country we have to test the best way of distributing the glasses. When in Rome, do as the Romans do. Sometimes the glasses can be sold via a local charity group, sometimes by social entrepreneurs, a hospital, the church, schools or a soft drinks manufacturer. Ultimately, we hope to sell the glasses on the street, from the man also selling telephone cards, the thread and ribbon salesman or the local grocer.” The plan for the future is to move glasses production to developing countries. Van Asbeck: “The lens machine is high tech, it will stay here for now. But the frames manufacture and assembling the glasses can be done anywhere.” In ’t Veld: “We hope that production lines will appear everywhere, because on our own we shall take a thousand years to supply everyone who needs them.”

For the Dutch market, the team is thinking of adjustable sunglasses or a spare pair of glasses to keep in the car. In ’t Veld: “And in America they want to use the glasses after a cataract operation, as your eyes need a few weeks to adjust slowly to their new eyesight.” Glasses for children is another important project they are working on, but it's a more sensitive subject. Van Noort: “Western doctors are afraid that children could damage their eyesight by adjusting the glasses wrongly. But that is, as a colleague in Ghana put it, ‘a luxury problem that you in the West can worry about’. A child without glasses who cannot follow his lessons is guaranteed to suffer greater damage.”