When Jimmy Blakley signed up to serve his country during the Vietnam War, his health and vision were pristine. But shortly after finishing his service in 1971, Blakley’s vision began to sharply deteriorate.

He said doctors discovered signs of Agent Orange, the toxic herbicide used during the war, in his blood and told him it was likely the cause of his vision loss. Over the years, he had surgery and eye injections but became legally blind in 1999. He used magnifiers on top of glasses to read and needed to sit 2 feet away to watch his 65-inch TV. He was frustrated.

Then Blakley, now 72 and living in College Station, Texas, learned about IrisVision, a device that uses a smartphone, virtual reality headset and algorithms to help people with poor vision see and read clearly. For Blakley it was life-changing.

“I was amazed,” he said. “I was seeing the bottom of the eye chart; it was like being 19 again.”

Among companies using technology to address vision problems, IrisVision is working to go a step further: Its device, in addition to improving sight, is expected to be able to diagnose conditions and test and even treat patients remotely within the next two years.

“It’s not aesthetically pleasing, but it does something that really provides a useful function for people,” said Jerome Wujek, program director and research resources officer at the National Eye Institute, part of the National Institutes of Health. “We are visual animals. If you lose your vision, you lose a big chunk of your life.” He said devices that use artificial intelligence to test, diagnose and treat remotely are the future because they will allow ophthalmologists, optometrists and others to treat people in rural and underserved areas.

The market for this technology could be huge. About 6.4 million Americans have poor vision that cannot be corrected by glasses or contact lenses, according to a 2016 National Academy of Sciences report. Of those, 4.2 million are older than 40. And as the “silver tsunami” of aging baby boomers sweeps the nation, age-related eye diseases and conditions, like macular degeneration, glaucoma and diabetic retinopathy, are expected to surge.

The coronavirus outbreak has made it particularly challenging for the visually impaired. People with weak vision rely heavily on touch and sound to identify objects and people, and this can be tough while following hand sanitizing and social distancing practices and listening to people through masks, said Dr. L. Penny Rosenblum, director of research at the American Foundation for the Blind, who has congenital cataracts and glaucoma. Those with poor vision can also find themselves even more isolated if they are unable to use Zoom and other technology to stay connected, Rosenblum added.

Frank Werblin, co-founder and chief scientist at IrisVision and a professor of neuroscience at the University of California, Berkeley, for more than 40 years, came up with the idea for Iris- Vision in 2014. While speaking at a Foundation Fighting Blindness conference, a board trustee, J. Lynn Dougan, approached him, offering to provide funding if Werblin could invent a wearable device that could help his vision- impaired daughter. Werblin said he had been fascinated by the relationship between brain neurons, the retina and vision, and eagerly accepted the challenge.

Along the way, Werblin brought in a tech-savvy mobile app developer, Ammad Khan, as a partner. “Imagining a concept that would transform somebody’s life was very compelling for me,” Khan said.

With $1.5 million from Dougan, a $1.5 million grant from the National Eye Institute and about $4 million from angel investors and venture capitalists, the co-founders got to work. They collaborated with experts from Stanford and Johns Hopkins universities and partnered with Samsung, which provided the smartphone; the augmented, virtual and mixed reality technologies; and the mobile artificial intelligence platform. By 2017 the device was ready.

IrisVision helps restore visual function to people with such conditions as macular degeneration, diabetic retinopathy, retinitis pigmentosis, Stargardt disease, glaucoma and optic atrophy — but not cataracts. It can help someone with visual acuity as low as 20/1000. (Acuity measures sharpness: A 20/200 acuity, for example, means a person can make out an object at a distance of 20 feet that a person with normal vision could see from 200 feet.)

So how does it work?

IrisVision helps the brain use parts of the eyes that still function properly. The smartphone’s camera captures an image, and then the virtual reality, or VR, headset and algorithms enhance the image by providing enough information to fill in the gaps and remap the scene to provide a complete picture.

The company recently added voice control, video streaming, Alexa and other interactive features that give those with weak vision easy access to news, weather updates, YouTube videos and TV shows viewed within the headset. The person can adjust the headset, by voice command or button, to zoom in or adjust the color, contrast or brightness.

Still, the device has its shortcomings: It is large and clunky, and the user needs to be stationary — not walking around — to use it. In addition, at $2,950, it is expensive. And unless you are a veteran, health insurers do not cover the cost.

IrisVision has seen an increase in sales during the pandemic, rising 50% in June from the same month a year ago, according to Khan. He said that most of the devices were now being sold directly to consumers, as clinics where people often purchased them had shut down during the outbreak. IrisVision ships the devices to homes and then helps buyers set up the technology remotely.

A number of other companies are also working to address issues with poor vision, like NuEyes, eSight, Patriot Vision, OrCam, Vispero and Aira. Patriot’s ViewPoint, Vispero’s Compact 6 HD Wear and NuEyes e2 all offer VR headsets similar to IrisVision’s, although magnification, field of view and other features vary among models. Some devices, like e2 and Compact Wear, are less expensive but offer fewer features.

They also vary in size and weight. NuEyes Pro, eSight and Vispero’s Jordy resemble oversize sunglasses or ski goggles and are designed for walking down the street, visiting museums or shopping, which IrisVision is not.

“We’re still in the very, very early days,” said Kjell Carlsson, a senior analyst at Forrester Research. He said the size and price would need to come down before the devices became mainstream.