Electronic Bifocals
About ninety percent of people over age 45 suffer from presbyopia. This is the condition in which the crystalline lens of our eyes loses its flexibility. As a result, as we get older, it’s harder for us to focus on close objects. This loss of flexibility actually takes place over a number of years. However, typically we don’t notice it until our mid-40s. Presbyopia is a natural part of the aging process of our eyes.
So far, scientists know of no way to prevent presbyopia. Fortunately, however, optometrists can take care of the problem by prescribing reading glasses, bifocals, or trifocals. In fact, the majority of people in the U. S. over 55 wear some type of bifocals (or trifocals).
Although regular bifocals are an adequate remedy, they do have their drawbacks. Typically, they don’t handle the mid-range focus area very well. I myself wear bifocals, which work adequately for reading and for distance vision. However, I often have to keep switching my line of sight when I’m engaged in certain activities, like board games.
Furthermore, neither the close-up lenses or the distance lenses in my bifocals work right for using my computer. So I use a separate pair of glasses for my computer and for other mid-range work. This means I’m constantly switching back-and-forth from my bifocals and my computer glasses.
I’ve tried using trifocals and progressive lenses. Unfortunately, they both made me dizzy. My eyes were never able to totally adjust to them. Many other people experience the same problem.
Electronic Bifocals: The Answer
In the past five years, researchers at the University of Arizona have come up with a new answer: electronic bifocals. Each lens in these electronic glasses is composed of two plates with a razor-thin layer of shape-shifting liquid crystals sandwiched between them. One of these plates is covered with tiny, transparent electrodes. When a current runs through the electrodes, it causes the liquid crystals to rearrange themselves, thereby imitating the focusing of the human eye. All this takes place in less than a second.
A tiny battery within the frames of the electronic bifocals powers the electronics. When the battery is turned on, its focusing power allows the user to be able to read and perform other close-up tasks. When the switch is turned off, the glasses either become normal glass (for people with 20/20 distance vision) or they return to the focal strength required by that person for distance vision.
The exciting thing is that electronic glasses are not some far-distant scientific solution. Rather, electronic bifocals are due to hit the market in late 2010.