Presbyopia, Bifocals, Trifocals, & Progressive Lenses
At some point in life, almost everyone develops an eye condition called presbyopia. As we age, the likelihood that we will develop this condition increases, virtually reaching 100% by the time we turn 65. Also known as age-related farsightedness, this condition affects the eyes’ ability to focus, and it cannot be treated with standard glasses or contacts. Like graying hair or wrinkles, presbyopia is simply an unfortunate natural side effect of aging. While this condition can’t be totally prevented or cured, we can effectively address it with specialized corrective lenses that help bring things of different distances into focus.
Our eyes have evolved the capacity to focus on objects at varying distances. They do this by bending and flexing the eyes’ lenses using tiny muscles. As we get older, those muscles weaken, our lenses lose flexibility, and we can’t bend our lenses as far as we once could. Because the lenses must bend further to focus on nearby objects than distant ones, these processes make it difficult to read and discern close objects. Most people begin to experience this difficulty seeing nearby objects around age 40, and as the eye muscles weaken further, presbyopia usually becomes more and more severe.
Bifocals have two different corrective areas on each lens: a top half that compensates for nearsightedness, and a bottom half that compensates for farsightedness. With these types of glasses, you can simply look downward to bring close-up objects into focus. In more severe cases of presbyopia, the eye muscles may weaken so much that they can’t focus on objects at middle distances like televisions and computer screens. Trifocals, which have a third lens strip between the two corrective areas, can treat this issue.
Not everyone is a fan of bifocals and trifocals. For some people, the immediate transition between eye prescriptions is too abrupt and/or distracting. Progressive lenses work in essentially the same way as traditional bifocals and trifocals, but the power level of the vision correction changes gradually along a gradient. This makes it so that wearers can focus at any distance by tilting their heads, all without the jarring jump of more traditional lenses that treat presbyopia. The main drawback of progressive lenses is that the bottom corners of the wearer’s field of vision are blurred. However, with developments in lens technology and design, this issue has improved in recent years.
Bifocals, trifocals, and progressive lenses usually take some time to get used to, but they’re extremely effective. If you’ve noticed that you’re having a harder time focusing on nearby objects or text, it’s likely that one of these solutions can help. If you’re interested in these or any of the many services we offer, contact Georgia Eye Physicians & Surgeons to schedule an appointment today. Be sure to follow Dr. William Segal and Dr. Marc Lay on Facebook and Twitter for more eyecare information, fun facts, and the latest news and updates about eye health.