What are bifocal contact lenses?
Bifocal contact lenses are lenses that provide correction for both near vision and far vision. There are several basic types of bifocal contact lenses:
- Lenses with the distance prescription in the center of the lens and the reading prescription all around it. In some cases, the reading prescription is on the inside and the distance prescription is on the outside.
- Lenses with the distance prescription on the top and the reading prescription on the bottom (like bifocal glasses). These lenses are usually weighted at the bottom so the reading prescription stays on the bottom when they are being worn.
- Lenses with magnifying power becoming progressively greater from the outside to the center of the lens (called aspheric bifocal lenses).
When are bifocal contact lenses prescribed?
Bifocal contact lenses may be helpful for people who have trouble seeing things close up (for example, reading small print) and do not want to wear reading glasses or bifocal glasses.
Usually, bifocal contact lenses are prescribed for both eyes. Sometimes a bifocal contact lens may be prescribed for only one eye, and a regular lens or no lens at all for the other eye.
How do I choose the right type?
You may need to try several different types of lenses. Bifocal contacts come as soft lenses and gas permeable ("hard") lenses. Your doctor can recommend which type you should try, and trial lenses can be ordered.
The selection of type of bifocal contact lens is based on factors such as:
- your age and eyeglass prescription
- the type of work you do
- the way you usually use your eyes (for example, if you look straight ahead to read rather than looking down)
- the lighting conditions where you usually read
- the shape of your eye
- the size of your pupils.
What happens during the adjustment period?
You may adjust quickly to bifocal contacts, but many people have some problems with their new lenses. You may feel that your vision is not as clear as you are used to, or it may change when the lens moves on your eye. You may see images that seem to jump when you change from distance to close-up vision, a three-dimensional effect or ghost image when you read, or a flare around lights. Problems like these can sometimes be corrected with a change in lenses.
Will bifocal contact lenses work for me?
Bifocal contacts work for many people, but they are not for everyone. There have been many improvements in bifocal contact lenses since they were first used. Work with your eye doctor to find the type that is best for you, and try it for as long as your doctor recommends. Discuss your trial experiences with your doctor, and then decide whether bifocal contacts are the right choice for your vision needs.