The manufacturing process behind contact lenses is a fascinating blend of science and technology. Since their early invention, contact lenses have progressed a long way, transitioning from glass to hard plastic and finally to the soft materials we use today. In this blog post, we’ll delve into how exactly contact lenses are made and how manufacturers have revolutionized the way they are produced by harnessing modern technology and materials.
The journey begins with selecting the base material. Soft contact lenses are typically made from hydrogel or silicone hydrogel, which are chosen for their oxygen permeability and biocompatibility. These materials allow your eyes to breathe, which is essential for healthy wear. Rigid gas-permeable (RGP) lenses, on the other hand, prioritize oxygen permeability even further. They are primarily made from highly durable and breathable plastics like fluoropolymers combined with silicone.
Once the material is chosen, the lenses undergo a molding process to achieve their final shape. Here’s where the methods differ.
Soft contact lenses are made through spin-casting or lathe-cutting process. Spin-casting involves depositing liquid plastic into molds and then spinning them until the plastic takes the desired shape. Lathe-cutting, meanwhile, involves carving the plastic into lens form. Computer-controlled tools meticulously sculpt the lens from a disc of material. Both methods lead to polishing for comfort and hydration before reaching your eyes.
RGP lenses prioritize oxygen permeability, which is crucial for healthy corneal function. Their shaping process utilizes lathe-cutting, which offers greater precision for intricate designs. It meticulously sculpts the lens design from the disc, similar to a woodworking lathe but with incredible accuracy. This allows for intricate shapes and sharper edges. RGP lenses can have complex curves and features to address specific vision needs, like astigmatism. Lathe-cutting enables these intricate geometries. Additionally, precise cutting ensures clean and sharp edges on the lens, which is necessary for optimal tear flow and lens stability in the eye.
Following the molding stage, both soft and RGP lenses undergo additional processes to ensure comfort and clarity.
Polishing: Lenses are polished to achieve a smooth and comfortable surface for wearers. This step is essential for both soft and RGP lenses to minimize irritation.
Hydration (Soft Lenses Only): Soft contact lenses are bathed in a sterile solution to absorb water and achieve their characteristic flexibility. This step is not required for RGP lenses.
Every lens, soft or RGP, undergoes rigorous inspection for any defects or imperfections. This enables your scleral optometrist to provide you with only the highest-quality lenses. Finally, the lenses are packaged in sterile blisters filled with saline solution. This solution keeps soft lenses hydrated and all lenses ready for use.
Today, advancements in eye care have led to the development of customized contact lenses for specific eye conditions. For example, specially crafted lenses can now be made for irregularly shaped corneas.
Additionally, advancements in materials have led to extended wear options for both soft and RGP lenses, allowing comfortable wear for extended periods. If you are undergoing dry eye treatment, be sure to work closely with your eye doctor to find the best solution for your vision needs.
The manufacturing process of contact lenses is a complex and precise dance of science and technology, catering to the specific needs of soft and RGP lenses. The next time you pop in your lenses, take a moment to appreciate the incredible journey they’ve taken to help you see the world clearly and comfortably.
For more information about contact lenses or Neurolens treatment, reach out to Lumen Optometric. Call us at (626) 921-0199 or fill out our contact form to schedule an appointment.
In today's digital age, it's nearly impossible to avoid exposure to blue light. From the…
One common eye condition that often goes unnoticed until it becomes bothersome is presbyopia. This…
At Lumen Optometric, we often encounter patients who wonder if contact lenses are a viable…
Seasonal eye allergies can turn your fall season into a time of discomfort. Our eyes…
Our eyes play a crucial role in our daily lives, yet it's easy to overlook…
Lazy eye, or amblyopia, is a condition that affects many, reducing visual acuity in one…