Casting optical lenses produces an error-free surface
"Often, patients will return to an optical dispensary with a complaint about their recently purchased eyewear," said Phernell C. Walker, II, ABOM, Master in Ophthalmic Optics. "Their complaint is, 'I just don't see clearly out of those glasses.'
"One of the main reasons for that lack of clarity is surface errors," Walker added.
Walker spoke to the alternative-casting optical lenses-during the symposium, "Controlling Service, Cost, and Quality," presented at the Ophthalmology Times/American Association of Dispensing Ophthalmologists Dispensing Solutions Pavilion.
"Casting eliminates many of those errors and creates an accurate prescription every time without waiting for back orders," Walker explained.
Traditional surfacing of a lens involves a machine that physically cuts the surface of a blank lens, leaving errors such as radial and astigmatic errors, spherical aberrations, and curvature of field.
Casting lenses, which can be done in-office, involves pouring liquid monomer into a gasket, producing a lens that is surface-error free. In addition to an error-free surface, the benefits of cast lenses include: