contact lenses , methods and systems for accomplishing the requirement for biocompatibility of oxygen delivery to the eye , and the cornea in particular , when elements and components are used which reduce the transmissibility of oxygen and which require coverage of a significant area of the non - vascularized cornea . a contact lens assembly is provided , comprising : an anterior surface , a posterior surface and at least one element or component having a substantially low oxygen permeability disposed within the lens . the contact lens also includes a layer having an oxygen permeability greater than the aforementioned element or component . the thickness of this layer is such that the layer provides an equivalent oxygen percentage to the cornea beneath the aforementioned element or component .