How Contact Lenses Are Made – Part 2
In Part 1 of this two part series, we looked into the initial creation of contact lenses. In this second part, we’re going to look into what happens after the main contact lens has been created – the finishing, quality control checks and finally the packaging.
Finishing – after the contact lens has been created, either by moulding or lathing, the lens requires more specific curvature to be created for it fit comfortably on the wearer’s eye. As with the polishing part of the lathing process when creating the contact lens, the contact lens is placed upon an arbor where small slices are taken, followed by precise smooth finishing with emery paper.
Quality Control – further to the contact lens being created and finished, each contact lens must pass through a rigorous Quality Control procedure. This is carried out throughout the manufacturing process and once again at the end, by two separate procedures. Firstly, the contact lenses are viewed under a microscope to see any obvious problems. Secondly, a shadowgraph is created of the contact lens, which shows any issues with the contact lenses on a greater scale for easier viewing. Whilst some differences between contact lenses may be not be problematic (mainly for cosmetic contact lenses), if the contact lenses are custom made, it is extremely important that any issue or problem with the contact lens is discovered and amended before it is ready to be sold.
Packaging – before the contact lenses can be delivered to the store or pharmacy, they must be packaged to a certain standard. Generally, contact lenses are first boiled for hours and packaged in sterile material, with a saline solution. Once this process has taken place, the contact lenses are ready to be delivered and worn.