Contact lenses – parameters, characteristics of the polymers

Abstract

Contact lenses-parameters, characteristics of the polymers • Dynamic development of contact lenses has been observed in recent years. Their diversity allows to choose those that are tailored to the individual needs. Soft lenses are becoming more popular and most people are wearing them constantly selecting monthly lenses instead of day lenses due to the lower cost of their use. Lenses made with newer materials such as lotrafilcon A and balafilcon A are used as a dressing lens for continuous wearing after surgery. The combination of hydrogel and silicone allows to achieve the comfort of wearing a soft hydrogel lenses with even higher solubility of oxygen in the silicone. Important parameters defining contact lenses are hydration, oxygen permeability coefficient, refractive index and Young's modulus. Development of soft contact lenses technologies as a drug carriers concern for example: incorporation of nanocapsules, liposomes or molecular printing.