Computer glasses differ from regular eyeglasses or reading glasses in a number of ways to optimize your eyesight when viewing your computer screen. Computer screens usually are positioned 20 to 26 inches from the user’s eyes. This is considered the intermediate zone of vision — closer than driving (“distance”) vision, but farther away than reading (“near”) vision.
Children and young adults who need prescription eyeglasses usually are prescribed single vision lenses. These lenses correct the wearer’s nearsightedness, farsightedness and/or astigmatism, and the shape of the lens inside the eye automatically adjusts to provide the extra magnifying power required for computer vision and near vision.
When a person’s close-up vision becomes less clear due to presbyopia after age 40, this age-related loss of natural focusing power affects reading and seeing a smartphone or computer vision clearly and comfortably. Bifocals can provide clear distance and near vision, but intermediate vision (needed for computer use and seeing your smartphone) often remains a problem. And progressive lenses or trifocals, though they offer some help for intermediate vision, often don’t have a large enough intermediate zone for comfortable computer work.
Without computer eyeglasses, many computer users often end up with blurred vision, eye strain, and headaches — the hallmark symptoms of computer vision syndrome. Worse still, many people try to compensate for their blurred vision by leaning forward, or by tipping their head to look through the bottom portion of their glasses. Both of these actions can result in a sore neck, sore shoulders and a sore back.
Though they sometimes are called “computer reading glasses,” it’s best to call eyewear designed specifically for computer use “computer glasses” or “computer eyeglasses” to distinguish them from conventional reading glasses. Generally, computer glasses have about 60 percent the magnifying power of reading glasses. But the optimal magnification depends on how far you prefer to sit from your computer screen and how close you like to hold your digital devices.
Computer glasses also should accurately correct any astigmatism you might have, and precise measurements should be taken to insure the optical center of each lens is directly in front of your pupils when you are using your preferred working distance.
For these reasons, computer glasses should be customized to your individual needs. Using weaker, non-prescription reading glasses for computer work and seeing your digital devices typically won’t provide the accurate vision correction you need for sustained clarity and comfort.
Computer glasses put the optimum lens power for viewing your computer screen right where you need it for a clear, wide field of view without the need for excessive focusing effort or unhealthful postures. University research also shows custom computer eyewear can significantly increase worker productivity.
Stay Tuned for Part Three
For more helpful eye care and vision care tips, please visit our main blog page.