Novel low cost precision plastics molding for healthcare

Over 150 million Americans spend - $15 billion/yr for corrective eyewear to compensate for refractive error. Presbyopia, the age related loss of accommodation, affects everyone by about age 50. One quarter of US - sold lenses in 1999 were Progressive Addition Lenses (PALs), used to correct Presbyopia. This fraction will increase as the population ages. Commercially available pre-fabricated PALs require a design compromise for each patient and pattern of usage. All PAL wearers must accept the tradeoffs selected by the lens manufacturer - for some lens wearers these tradeoffs may be nearly optimal, but for others they may be so uncomfortable that the lenses are rejected. The alternative, custom ground PALs, is prohibitively expensive. Squid Labs is developing a novel, programmable molding technology, based on our existing prototype for fabrication of simple lenses. 'Mass customization' of corrective lenses will be achieved using a variable, programmable, and thus reusable molding membrane. Phase I proposes 1) computer modeling of the novel membrane, based on analysis of commercially prefabricated PALs, to determine elastic requirements for PAL production; 2) fabrication of prototype membrane(s) with the minimum necessary properties, using several different processes; and 3) casting and analysis of lenses made using these membrane(s). Confocal microscopy and Shack Hartmann wavefront sensing will be the principal methods for evaluating lens surface topologies. The fabrication method producing the best membrane, judged by the caliber of lenses produced, will be utilized for Phase II activities: 1) construction and testing of a more powerful membrane able to produce arbitrary lens surfaces and 2) development of a production level prototype lens fabrication machine utilizing the membrane