Contact lens manufacturing method
AssigneeDaysoft Limited
InventorRonald Hamilton
Life of this patent
Estimating the term…
Abstract
In manufacturing a contact lens, a contact lens mould arrangement in which the engagement between the mould halves is unconstrained and at least one mould half is sufficiently pliable or flexible that during the curing of the contact lens composition at one mold half may move or flex relative to the other to define a post-cure mould cavity of smaller volume than the precure mould cavity and during which the curvatures of the first and/or second mould surfaces are allowed to change provides a significantly more efficient manufacturing process and enables one mould half to be readily utilized as a blister cup for contact lens packaging.
Claims10
A female mould half comprising an annular ridge, wherein the female mould half has a degree of flexibility such that under curing conditions and in contiguous contact via the annular ridge with a male mould half, the female mould half, including the annular ridge, is configured to flex as a result of any shrinkage of lens-forming monomer composition during curing, wherein the annular ridge is configured to flex radially, and wherein the female mould half comprises a first concave mould surface to correspond with a convex surface of a contact lens and comprises a curvature to correspond with a pre-determined lens power/curvature.
Dependencies are inferred from the claim text.