Both prescription colored contact lenses and non-prescription ones can be made of soft or hard materials. And both soft and hard types of those colored lenses come from various kinds of polymers. In those early days, hard contact lenses were made from PMMA, which also brought certain shortcomings. And then some lenses were produced using certain variants of silicone hydrogel.
Until now, some types of contact lenses are benefiting from the rapid advancement in technology that rigid gas permeable polymers are widely used. This is not the end. The most advanced lens material available nowadays is hydrophilic ones. These materials are capable of absorbing water as well as allowing oxygen to access the cornea. With these features, they can offer ultimate comfort.
Whichever lens material to choose, lens maintenance is crucial to eye health. After a long period of development, there are certain maintenance tips commonly suggested in the lens realm. A basic requirement is to store the lenses not being used in a lens case. Such a simple case is helpful in blocking any external infection. And cases with screw-down lids are favorable because they can prevent lens solutions from leaking out. In the case of keeping several pairs of lenses, it is a necessity to differentiate them. Different pairs of lenses can not stored into cases in a mixed way. An easy way is to buy lens cases with different colors.
Lens cases are also worthy of careful maintenance. Over time, dust and bacteria may build up in the case. In this sense, lens cases need to be regularly washed. In some instances, boiling them for a few minutes is necessary. This is a more thorough way of cleaning. After washing or boiling a lens case, it should be dried out before storing lenses back into it. Most doctors suggest that lens cases should be cleaned at least once a week.