Bifocal lenses are lenses that contain two lens powers which can help you to see correctly at all distances. When you look at a pair of glasses, you can perhaps see a bifocal lens. It will look like there is a small lens inside another or perhaps up to half of the lens is different. Most people chose to have progressive lenses that eliminate this line where you can see the distinct change in lens, but there are advantages in keeping your bifocal lens, in particular having a wider lens for reading.
Bifocal lenses are used for people who are both nearsighted and farsighted. It is common for people who are over the age of 40 to begin to notice a change in their vision and require the need for bifocals. As we age, our eyes begin to have trouble focusing on objects at different distances away. Some people manage to get away with progressive lenses for some time, they get used to the delay as the vision focuses. These are symptoms of presbyopia, and like I said, are common to those over the age of 40.
However bifocals are not limited to those ‘over the hill’. Children can benefit from bifocal lenses if they have problems focusing or have eye strain from reading. Reducing this demand of focusing from reading and writing work can help reduce myopia in young people. Also astigmatisms can be corrected when wearing bifocals if the wearer has other eye defects as well.
You can be prescribed one of several types of bifocal lenses. There is the flat top bifocal lens, where the nearsighted lens is located in a segment in the lower portion of the glasses with a straight line along the top, curving into a D shape down to the bottom of the frame. The near sighted lens can also take on a round shape, a narrow rectangular shape, also known as a ribbon lens, or take up half of the lens. The upper half of the lens is dedicated to the distant sighted lens. The lens is typically placed along the line of your lower eyelid.
With the demand to be using computers more and more often these days, there is a demand for the change in eyewear technology. People using bifocal lenses complain that the need to use the lower lens or near sight lens is difficult when working on a computer. We generally look straight at a computer, unlike looking down to read and write. Motorists may also find difficulties in finding that sweet spot when driving and consulting a map or checking gauges on the dashboard.
Bifocal contact lenses are an option, and you should consult your eye doctor whether they are an option for you. Consider comfort and your lifestyle when deciding whether to use contact lenses or glasses. Get your eyes checked at least every two years as most people find that they needed bifocal lenses long before they got them.
If you need to make an appointment with an optometrist contact Innovations in Eyecare today