Contact lenses

Abstract From the Canadian patent

There is disclosed a soft, hydrophilic plastic corneal contact lens comprising a substantially circular optical correction zone which is shaped for the correction of astigmatism. The lens is soft enough to tend to conform to the shape of the cornea when placed on an eye with corneal astigmatism. The lens comprises at least one discrete lug or flange extending from the periphery of the correction zone, the lug having a radial width measured from the periphery of the correction zone which is less than the radius of the correction zone. The lug is adapted to engage the sclera of the eye adjacent to the cornea, at, one of the depressions on the eyeball formed between the four rectus muscles …