Have you ever wondered how your magical little lenses are made? These tiny little disks provide you with clear sight every day and correct an astigmatism you’ve had all your life. It must be a super complicated process right? Nope, it is actually quite simple. Contact lens production has come a long way since the 17th century, here is how lenses are made today.
METHOD 1: LATHE CUTTING
A lathe (a fancy machine which rotates at +/-6,000 revolutions per minute) shapes small pieces of silicone to match the exact dimensions of your eye.
Years ago, multiple technicians worked together to shape, polish and perfect your lenses. More labour equals money! They were expensive. Fortunately, we have traded hands for machines. These super smart computers operate many mechanical arms which perfectly shape your lenses for you. Humans then put the lenses through multiple rounds of testing, ensuring that everything is as it should be.
Lathes are also used when manufacturing disposable lenses. Once the lenses are shaped and polished, they’re put into a hydrating solution to increase their water content. This process takes much longer but results in a much more flexible, comfortable lens. Flexible, comfortable and hydrated - sounds like somebody who has been to the spa for a day.
METHOD 2: INJECTION MOULDING
More commonly, injection molding is used to produce contact lenses. As per the method above, manipulation of silicone is involved, but that is where the similarities end! The silicon material is heated up until it reaches melting point before being blasted into molds. This liquid is called silicone hydrogel. Once all the molds are filled, they are cooled and become solid once again. They’re then buffed, polished, and quality checked for any imperfections. Once all of that is complete, they’re slipped into a blister pack of saline solution to soften while being transported to us. Now that is travelling in style!
Whether it is a spherical, astigmatism, progressive, bi-focal, multifocal, extended range, or RGP contact lens you can guarantee they were made using either of the above methods. Not only have contacts evolved in comfort, water content, and diversity but also in manufacturing. Every step of the way, your lenses are taken care of to ensure you re’see’ve the most comfortable lens possible.
