It started with a line in a book that Martin Aufmuth says he could not shake.

“When Martin Aufmuth, a math teacher in Erlangen, Germany, read in 2009 that hundreds of millions of people worldwide suffered from vision impairment but could not afford glasses, he could hardly believe it. “It was the book Out of Poverty by Paul Polak,” Aufmuth remembers, “I thought, ‘This can’t be true.’” But it was and it is.

The World Health Organization estimates that at least one billion people have a near or distance vision impairment that could have been prevented or has yet to be addressed. Eighty percent of them could be helped with relatively easy means, like glasses.

The day after reading Polak’s book, Aufmuth passed a one-euro shop and spotted reading glasses for a single euro.

“I thought, strange, we have this here,” he says. “Why not elsewhere?”

After researching existing efforts, he found no large-scale solution that satisfied him. Donated second-hand glasses, often mismatched and poorly distributed, did not seem sustainable.

“That wasn’t a solution for me,” he says.

Aufmuth said he had been looking for ways to make a difference for years. Inspired in part by his wife’s advice, “then do something”, he had raised funds for development initiatives in Malawi and organized climate campaigns that mobilized hundreds of thousands of children.

“I realized,” he says, “that even as an individual, I can move something.”

He then began working in his basement and developed the EinDollarBrille, or “One Dollar Glasses”, made from highly flexible spring steel wire and shatterproof plastic lenses.

Manufacturing the glasses requires no electricity or industrial production, only a compact, hand-powered bending machine small enough to fit in a shoe box.

“I was looking for a technical solution that could have a big impact,” he says. “That was it.”

In 2011, Aufmuth traveled to Uganda with a group of eye specialists, carrying two prototype machines. He trained local participants to produce the glasses themselves.

“People were already lining up outside, waiting for glasses,” he recalls. “We could start immediately.”

By 2012, he founded the organization that later expanded internationally as GoodVision. Today, the network operates in 11 countries, employs around 600 people and is supported by volunteers around the globe.

Much of its funding comes from individuals rather than governments.

“Private donations keep us moving,” Aufmuth says. “Every €10 [about $11.70 U.S.] means another person can finally see.”

Production and distribution are localized. Glasses are manufactured on-site and sold for the equivalent of two to three days’ wages, about five euros in Malawi and four in India.

“In Malawi,” Aufmuth notes, “that’s roughly the price of a local chicken.”

Aufmuth said the effect of a pair of glasses is often immediate. He recalled a 10-year-old boy in a Brazilian favela who put on his glasses, looked at his mother and said, “Ah, so that’s what you look like.”

He also described a teacher in Bolivia who could read her students’ work again and, for the first time, read to her grandchild.

The Seva Foundation estimates that $447 billion in productivity is lost every year due to impaired eyesight.

Aufmuth said a woman near Lake Titicaca, on the border between Peru and Bolivia, told him that with her new glasses she could again sort seed potatoes. He also described a Brazilian farmer harvesting açaí fruit who no longer had to climb trees just to check ripeness, and a grandmother in the Amazon with 56 grandchildren who regained her ability to sew clothes for her family.

“If a farmer can’t see properly, yields drop,” Aufmuth explains. “In Malawi, that might mean three months of hunger instead of two.”

He said at least half the organization’s work is in education and outreach.

“Many people don’t even know what they’re missing,” he says.

He also pointed to a shortage of trained eye care workers.

“The few opticians and doctors are in cities,” he says. “In rural areas, there is often no care at all.”

GoodVision trains local technicians to make glasses and conduct basic vision tests. In India, mobile teams, often young women from rural areas, travel six days a week to remote villages and currently distribute 6,000 pairs of glasses each month.

“What they do is remarkable,” Aufmuth says.

In Brazil’s Paraná state, the organization partnered with public systems to test 300,000 schoolchildren within a few months, which he described as a “mammoth operation.”

The work has also expanded into cataract care. In India and Burkina Faso, the organization now helps coordinate surgeries, arranging transportation and funding for patients who would otherwise never reach a clinic.

“We realized,” Aufmuth says, “that many had never been to a hospital, not even once.”

GoodVision has reached more than one million people, but Aufmuth said the scale of unmet need remains immense.

“A million glasses sounds like a lot,” he says. “But compared to the need, it’s very little.”

He said political uprisings, floods, fires and hurricanes have hampered work on the ground.

“In Bolivia, the gas is currently tainted, preventing engines from running,” he says. “There’s always something.”

“What drives me is fairness, the idea that everyone should have the chance to see, to learn, to work.”

“People often say one person can’t make a difference,” he says. “That’s just an excuse. You have to start something, set it in motion.”

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