June 2004

Custom Glasses

No more stars and halos: A new way of making corrective lenses accounts for a person's unique vision flaws.

By Technology Review

You probably think of eyeglasses as personalized, but in fact current ophthalmic methods only correct for the most common vision problems-leaving the remaining 20 percent uncorrected and many glasses wearers seeing stars, halos, or other apparitions. A San Diego, CA-based startup, Ophthonix, is developing a system-which could be on the market by year's end-for making glasses that are truly tailored to a person's unique vision flaws. The process begins with a device that measures all of each eye's aberrations, such as irregularities in the shape or density of the lens or cornea. Conventional diagnosis, in contrast, relies on a patient's subjective choices from among a series of corrective lenses. The Ophthonix device shines light into the eye and measures changes in the wave properties of the light reflected back by the retina; from these changes, it can calculate the measurements of any existing irregularities. The system then uses those measurements to create a digital prescription that it forwards electronically to Ophthonix. At the company, the prescription guides a laser as it scans a lens made up of a layer of conventional material fused to a layer of a novel polymer developed by Ophthonix. The laser light changes the molecular structure of Ophthonix's polymer, altering its refractive properties from one point to the next. In tests on patients, even those with 20/20 vision could see more clearly with the new glasses.