GoKawiilIf you have irregularly shaped corneas or a vision condition that requires hard contact lenses -- such as severe nearsightedness, farsightedness or astigmatism -- you know that finding the right fit can take weeks of trial and error. That could all change with 3D-printed contact lenses that take under 20 minutes to produce.
A press release published on Tuesday reports that researchers at the University of Waterloo's Department of Chemistry in Ontario, Canada, have developed a contact lens system that uses custom software to digitally map each patient's cornea, i.e., the clear, dome-shaped outer layer that covers the front of the eye.
Instead of relying on premanufactured lenses in set sizes, the platform would create personalized lenses that conform to your cornea's shape and size with a rapid production time -- allowing clinics to design, print and dispense custom lenses in one visit. The team also invented and provisionally patented a 3D-printable silicone designed for patient safety.
"Our goal is for the printed lenses to perform equivalently to current commercial contact lenses in terms of surface properties, including smoothness to prevent abrasion, stability under standard cleaning and storage conditions and oxygen permeability," Shirley Tang, one of the researchers behind the study, told CNET via email.
How the 3D-printed contact lens system works
Contact lenses are typically made of silicone, but that material won't work with a 3D printer. The Waterloo researchers created a hydrophilic (aka water-loving) silicone formulation that works with a DLP (digital light processing) 3D printer and doesn't compromise on safety or oxygen flow.
According to a research article published by the Waterloo team in June, the cornea's lens geometry is generated using algorithms that then produce thickness maps for 3D printing.
"Our software designs a lens with an inner surface that precisely matches the patient's cornea and an outer surface that provides the required vision correction," said Sayan Ganguly, a chemistry research associate at the University of Waterloo, in the press release.
What results is prescription-specific, personalized contact lenses.
Since 3D printing builds objects layer by layer, this can result in imperfections on curved surfaces, such as contact lenses, leading to discomfort and reduced clarity. Researchers overcame this obstacle by designing a thin coating that smooths out surface imperfections while maintaining both shape and clarity.
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