As in every field, technology keeps moving us forward. The contact lens industry has seen great advancements in materials, designs, and options in contact lenses. This article will offer a basic overview of contact lens materials. Your eye doctor can determine the best option for your individual needs.
Soft or Hard?
People have broken down lenses in to “soft” and “hard” for many years. The first contact lenses were made from a stiff, durable plastic. They weren’t called “hard contact lenses” until the invention of “soft contact lenses”. Soft contact lenses are made of plastic that is hydrated. The material is flexible unlike “hard lenses”. Over time, however, technology brought us innovations in the “hard” lens marketplace with the advent of “gas permeable” contact lenses which are still rigid, but since oxygen can travel through the plastic they are more comfortable and healthier then the original “hard” contact lenses. Below is a summary of materials, and then a summary of designs:
“Soft” materials are made from a plastic polymer that depends of hydration to remain comfortable and flexible. The lenses allow air to travel through the matrix of the material. The lenses are comfortable right from the start, but do not last as long as gas permeable contact lenses. These lenses are available in disposable options.
“Gas Permeable” materials are made from a rigid plastic that allows air to travel though the contact lens. The permeability does not require hydration. The lenses float of the tear film on the surface of the eye and typically offer sharper vision than soft contact lenses. Gas Permeable contacts are more durable and are typically replaced every 6 months to 2 years depending on the patient and their particular situation.
“Hybrid Lenses” are a combination of both soft lens material and gas permeable materials. The center portion of the lenses are made from gas permeable material and is surrounded by a ‘skirt’ of soft lens materials. Hybrid lenses offer the clarity of gas permeable contact lenses, but comfort that is closer to soft contact lenses.
In another article, we’ll look at different contact lens designs in each of these materials. Ask your doctor about what is new in contact lenses. Many patients have thought they weren’t good candidates for contact lenses, but they may be great candidates after all.