A switchable contact lens prototype was fabricated and tested with integrated off the shelf electronic components to drive a liquid crystal active lens element. This prototype was capable of changing its focal power by an average of +1.9D, but a maximum of +3.2 ± 0.2D was also measured. Switchable focus contact lenses are intended to help restore functional near and intermediate vision accommodation to those suffering from presbyopia, an inevitable age-related eye condition. The custom PMMA contact lens substrates used in this prototype are equivalent to commercially available scleral contact lenses. It was discovered that more careful design considerations are needed when at least one of the substrates is <100µm thick (which is needed for a final device). Without these design considerations, the switchable focal power of the lens is susceptible to change as the liquid crystal insert layer is able to flex. The prototype has an on-board electronics platform which was self-powered with a battery. Illuminating the electronics package with a 600Hz infrared signal switched the device on, which passed an AC voltage to the electrodes of the contact lens, reorientating the director of the liquid crystal with an electric field. To our knowledge, this is the first demonstration of a battery powered and wirelessly triggered smart contact lens for the treatment of presbyopia.
CORE (COnnecting REpositories)
CORE (COnnecting REpositories)