How Do Bifocal Contact Lenses Work?

Bifocal contact lenses are designed to provide good vision to people having a condition called presbyopia. The key detection that you're developing this condition is that you need to hold reading material, like a menu, further from your eyes to see it clearly.

Bifocal contacts are available in both soft and rigid gas permeable, allowing water to pass through, materials. Today's bifocal contact lenses are even available in a disposable or monthly, weekly, or daily frequent replacement wear. That means you get the convenience of throwing the lenses out at specified intervals and replacing them with fresh, new lenses. Given the fact that contacts for bifocal prescriptions have just recently been made available, most people wonder how do bifocal contact lenses work?

There are three types of lenses. These are aspheric, concentric and translating.

Translating lenses work much like normal bifocal eyeglasses. They have two powers on one lens: one to correct distance vision, if that's needed, and the other to correct near vision. Some contact lens designs feature two prescriptions, with the distance vision on the top of the lens and the near vision at the bottom, similar to a bifocal eyeglass with a line separating the powers. Other designs work more like progressive eyeglass lenses, where the different prescriptive powers are blended on different parts of the lens. Your eye learns to differentiate the proper power for the correct distance to be able to see close up and far off. These lenses have an edge on the bottom to keep them from rotating in your eye when you blink.

Aspheric lenses put both prescriptions near your pupil so you don't have to be concerned about "which way is up". Your eye becomes accustomed to choosing how to correct your vision.

Concentric lenses put your distance-vision correction in the middle of the lens and your near-vision correction on the periphery. Again, your eye adjusts by choosing where to look and again, there is no worry about whether or not the lens rotates in your eye.

The best way to figure out which bifocal lens design is right for you is to wear each of them and find out which one is the most comfortable.