Evolution of High Precision Manufacturing of Contact Lenses

Abstract

Today’s contact lens professionals must familiarise themselves with the various contact lens manufacturing methodologies that are capable of producing high accuracy optical products for their patients. Contact lens manufacturing dates back to the 19thcentury with the development of glass contact lenses and later evolved to various types of optical polymeric materials. The recent advances in the manufacturing of contact lenses can be attributed to the development of advanced polymeric materials and high precision processing technologies. Two basic techniques are identified for contact lens manufacturing. They are moulding method and ultra-high precision machining. Ultra-high precision machining is employed for direct shaping of contact lenses or for making mould inserts that will be used further in lens injection. Mould inserts can be made from high hardness steel, nickel plated steel, aluminium or other nonferrous alloys. Advanced light metal optical aluminium alloys provide a high integrity mould with fine microstructures for optical lens production. This review paper provides a chronological view of the evolution of contact lens manufacturing and identifies the importance of a recently developed aluminium alloy in the production of mould inserts for high quality contact lenses.