Optical Scientist Develops Trifocal Lens Technology

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An intraocular lens offers a solution to cataracts, which cloud vision with aging.

An intraocular lens (shown above) offers a solution to cataracts, which cloud vision with aging. However, it doesn't allow recipients to see at all distances. Trifocal intraocular lenses, on the other hand, provide vision at near, far and in-between distances, eliminating some people's need to wear glasses.

A University of Arizona optical scientist has designed implantable cataract replacement lenses for the eye that allow for mid-range vision and may eliminate the need for glasses or contacts for some people.

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Jim Schwiegerling

Jim Schwiegerling

The lenses were developed by Jim Schwiegerling, a professor in the Department of Ophthalmology and Vision Science in the UArizona James C. Wyant College of Optical Sciences.

As we age, the proteins that must be precisely structured to create the eye's naturally transparent lens begin to clump, causing cataracts that cloud our vision. The routine solution to this problem for nearly 50 years has been to surgically remove our natural lenses and replace them with artificial intraocular lenses. However, those lenses are unable to focus near, so the recipient must usually still wear reading glasses. 

In the 1990s, bifocal intraocular lenses became commercially available to address the issue. But the artificial bifocal lens design offers clarity for only two distances: near and far. 

"One of the complaints about bifocal lenses is that you can drive a car and read, but everything in between was kind of fuzzy and with all the screens (we use today), people wanted that extra intermediate distance," Schwiegerling said. 

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Intraocular trifocal lens.

Alcon's Intraocular trifocal lens design.

Alcon

With support from Tech Launch Arizona, the university office that commercializes inventions created from UArizona research, patents were filed and granted to the Arizona Board of Regents. Tech Launch Arizona then partnered with Alcon, a global medical device company specializing in eye care products and one of the largest producers of intraocular lenses in the world, providing the company a license to use the technology in its products.

Alcon incorporated Schwiegerling's patented technology in its novel trifocal intraocular lens, PanOptix, launched in Europe in 2015. Eventually, PanOptix was approved for use in countries around the world, but it wasn't until summer 2019 that the last two major countries – the United States and Japan – approved use of the new lenses. 

About half a million people around the world have now received Alcon's PanOptix lenses. 

"On the technological side, here's how it works: There’s this technology called diffractive lenses that look a little like mini lighthouse lenses – instead of smooth curve, the lens has little steps. If you alternate steps of different heights, you can create this third focus to use for computer distance," Schwiegerling said. "Alcon brought this technology to PanOptix, which has been used to treat cataract patients around the world."

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Jim Schwiegerling after eye surgery

Jim Schwiegerling (right) is not just the creator, but a user of his technology.

Jim Schwiegerling

Besides offering better eyesight through a third focal distance, trifocal lenses can also let more light into the eye, which creates sharper, higher contrast images, solving one more common problem of bifocal lenses. 

Schwiegerling developed cataracts several years ago, he said, but because PanOptix wasn't yet available in the U.S., he traveled to Germany to get them implanted for himself. 

"So I'm a user and not just a maker," he said. "I am thrilled with being able to do my outdoor activities, work at the computer and read without being encumbered by glasses. I see like I am young again." 

"It’s our primary goal to get inventions made at UArizona out into the public to really have an impact on society," said Doug Hockstad, assistant vice president of Tech Launch Arizona. "This is even more impressive and moving, seeing how much of an impact this is having not only on the world, but also directly on the inventor's own life."