Optical scientist develops implantable cataract replacement lenses
Dr. Jim Schwiegerling, a professor at the University of Arizona College of Optical Sciences, recently designed and developed implantable cataract replacement lenses for the eye. Courtesy Jim Schwiegerling.
A professor in the College of Optical Sciences at the University of Arizona, Dr. Jim Schwiegerling, recently designed and developed implantable cataract replacement lenses for the eye.
These lenses allow for mid-range vision and may eliminate the need for glasses or contacts for some people and are implanted into the eye after removal of the natural lens.
“The natural lens becomes stiff with age and people lose the ability to focus up close in their late 40s,” said Schwiegerling in an email.
The lenses tend to cloud with age but usually not until someone is in their 70s or 80s. The trifocal lenses are designed for these two groups and have three different focal lengths incorporated into the same lens using a diffractive optic.
“Diffractive lenses look something like miniature Fresnel lenses like those found in lighthouses,” Schwiegerling explained in an email. "Contacts have tried to do bifocal type lenses, but with limited success. Spectacles have bifocal and trifocal lenses, but this is achieved by the eye looking through different portions of the lens."
The three focal lengths are set so the person can read, see the computer screen and see things far away. The side effect of bifocal and trifocal spectacles is that they distort peripheral vision, causing some issues.
“For example, stair steps are magnified by the bifocal segment in the bottom of bifocal spectacle lenses and people need to compensate for this when walking downstairs,” Schwiegerling stated in an email.
Schwiegerling has been working with Alcon, the company that ultimately licensed the trifocal technology, for about 20 years. At the time of the development, there were bifocal lenses available.
One of the main complaints regarding bifocals was that people could see far away and read but most people had difficulty with their computer screens.
“This got me thinking about a trifocal design that would provide good vision at that intermediate distance,” Schwiegerling stated in an email.
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Schwiegerling had started the idea of trifocal lenses in the late 2000s and finally decided to write the invention disclosure around 2009. A provisional patent was filed in early 2010, and now about 10 years later it is available in the U.S.
For Schwiegerling, the most challenging part of developing the lenses was mainly time to flesh out the idea.
“I think researchers come up with plenty of novel ideas but need time to work out the details,” Schwiegerling stated in an email. "There's always a balance between teaching, writing grants, interacting with students, working on funded research projects and trying to pursue unfunded ideas that are potentially dead ends."
It takes trial and error to get any project like this done. Tech Launch Arizona helped support this project by partnering with Alcon.
“TLA has been immensely supportive in this entire process,” Schwiegerling stated in an email.
When Schwiegerling first joined the UA, invention disclosure seemed to just disappear. With the advent of TLA, the university has found a way to convert good ideas into licensed technology and spin-off companies.
“In my case, they evaluated the technology, filed the provisional patent, filed the full patent, worked with Alcon to license the technology and secured their financial support for worldwide patenting,” Schwiegerling explained.
Schwiegerling’s Australian patent was ultimately challenged by a competitor company. TLA helped him to work with the lawyers to help defend that patent.
“Finally, they have been receptive to looking at new ideas coming out of my lab and pursuing these technologies as well,” Schwiegerling stated in an email. "These types of lenses if successful will act like the young natural lens and provide good vision at all distances."
Schwiegerling is continuing to work on implantable lenses. The main area he is focusing on right now are lenses that provide a continuous range of vision instead of three discrete focal distances.
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