These are the original contact lenses, made from a rigid Perspex material. Whilst being very durable, these lenses do not allow essential oxygen to pass through to the surface of the eye. Hard lenses have now been largely replaced by "gas permeable" lenses. Occasionally, hard lenses are still used for specialist purposes. |
These lenses are made from semi-rigid plastic materials, which allow more oxygen to pass through to the surface of the eye, making them much healthier to wear. Gas permeable lenses only cover part of the iris. As these lenses float on your tears there is some movement whilst blinking, it therefore takes slightly longer to get used them. However once settled these lenses prove to be very comfortable. RGP lenses are suitable for most prescriptions, but more so for patients who have astigmatism, where they can give better standards of vision. RGP lenses are easy to handle, clean and very durable. |
