For many of us, presbyopia is a fact of life. Simply defined, presbyopia is the inability to focus on items in close range. This condition is caused by the lens in the eye becoming less and less flexible as we age. Unfortunately, most of us will need corrective lenses and even bifocals at some point as this condition worsens.

There are two types of contact lenses when you need a bifocal contact lens, the soft contact lens or gas permeable. The gas permeable lenses will last you up to a year before you will need to replace them, while the soft contact lenses are usually biweekly or monthly. The yearly contact lenses are often less comfortable due to protein build up and require weekly cleaning. Depending upon the type of eyes you have will in part make this decision for you. Those with allergies find a soft contact lens lasting for a month is about all they can handle even when they clean the gas permeable weekly. Another benefit of the soft contact is the material used to make it. It is soft and fairly easy to tear, but lighter on your eye than the gas permeable lenses.

A bifocal contact lens has two divisions. There is a line like you would find on your classes towards the bottom of the contact lens and another line towards the top. This helps your eye focus on the picture in front of you.

Bifocal contact lenses work just like bifocal glass lenses do; two powers of glass in each lens provide different focus adjustments, one for far away (distance) and another for close up. Both adjustments are contained in each contact lens. Different manufacturers make different types of bifocal lenses, and it may take some experimentation to discover which type is right for you.

Aspheric lenses have a more gradual change between focuses. Both of the powers are in the area of the pupil, and as with the concentric lens, the eye will adjust and learn to choose the proper focus to use.