Any contact lens wearer will know the incredible freedom that they can bring to your life. From taking part in adventures without worry, to transforming the way you look, there is no denying that contact lenses are a real blessing.
As technology advances, the science behind contact lenses becomes increasingly technical, and they work harder to suit the lifestyle and needs of the wearers.
How Are Contact Lenses Made?
The type of contact lens determines the manufacturing process. This changes according to whether the lenses are soft contacts, rigid gas permeable contacts, or hybrid lenses.
Soft contacts are made of plastic polymers known as hydrogels. These so-called ‘smart’ materials can absorb water and can become soft and pliable while still retaining their optical qualities, which makes them ideal for products such as contact lenses.
Soft contacts are formed by one of two processes; an injection molding process, or a lathe cutting process.
l Injection Molding
This process is when the soft material of the contact is heated until it reaches a molten state. It is then injected into computer-designed molds under immense pressure. The lenses are then quickly cooled, and removed from the molds. The edges are polished until smooth, and the lenses are hydrated, which helps to soften them. They then undergo the required quality assurance testing. Injection molding is the preferred method for creating disposable contact lenses as it is a faster and cheaper process than lathe cutting.
l Lathe Cutting
Non-hydrated ‘buttons’ of the soft contact lens material are each individually mounted onto spinning shafts. They are then molded to the correct shape using specialized, computer-controlled precision cutting tools. Both the back and front surfaces are shaped to the desired finish utilizing a cutting tool before the lens is removed from the lathe and hydrated. This step helps to soften it before the lenses undergo quality assurance testing. The lathe cutting process has become gradually more automated as technology has advanced, and it now takes only a few minutes to create one lens.
Silicone Hydrogel Contact Lenses
Soft contact lenses can now be upgraded to a more advanced option which better utilizes the unique properties of hydrogels. The material is becoming a favorite within a range of industries, and companies such as RD Medical Products Hydrogel Manufacturer are coming up with new and innovative ways to best use them, including in contact lenses.
Silicone hydrogel contact lenses allow more oxygen to pass through the lens and into the cornea of the eye, which can allow almost five times more oxygen to reach the cornea. This feature is a healthier option for your eye, allowing more moisture into the area and reducing the risk of your eye drying out and becoming strained.
The hydrogel within the lens can readily absorb water, and turn from hard, uncomfortable plastic to a soft, gel-like material which is far more comfortable to wear for an extended period.
Your eyes are valuable organs and need to be cared for and invested in wisely. By choosing the best possible lenses, you can improve not only your comfort but your long term optical health.