There are two main differences between reading glasses and computer glasses. The latter are designed to work over a longer distance. They also often contain a material designed to reduce screen glare. An alternative to buying separate glasses for reading and computer use is to purchase specially designed bifocals.
Reading glasses can be purchased at a pharmacy.
Keep in mind that there is a big difference between generic reading and computer glasses and those prescribed by an ophthalmologist or optician. Prescription eyeglasses will have custom lenses to meet the wearer’s specific eye disabilities. Generic eyeglasses often simply contain magnifying lenses similar to those found in a magnifying glass. While they may be right for many people, they are not a one-size-fits-all solution and may even do more harm than good.
Reading and computer glasses often meet different needs.
Dedicated computer and reading glasses often aim to meet different needs, especially in terms of distance. This is easy to observe in practice. Most people read books with their arms slightly bent, which means the book is about 18 inches from their eyes. For both visual and ergonomic reasons, the most common advice is that a computer screen should be at arm’s length from the reader, which can be up to twice the reading distance of a book. This requires a radically different level of magnification and point of focus.
Computer glasses are usually made to counteract glare from the computer screen.
Another difference from computer glasses is the need to counteract the effects of glare and reflection from a computer screen. This is a particular problem with older CRT screens, but it’s still a problem with modern flat panel monitors. This can be addressed with a slight tint to the lenses or a special anti-glare coating.
Specially designed bifocals can be used as reading and computer glasses.
Computer glasses may also need to be specially designed to deal with the fact that the eye focuses differently with the screen. This is because, compared to the printed page, the contrast of characters against the background of a screen is much less defined. The lower definition causes the eye to need continuous refocusing, even when looking at the same character.
There are several solutions to these differences, other than simply buying reading and computer glasses separately. One is to have special bifocals, with one part of the lens dedicated to reading the printed page and the other part customized for use on the computer screen. This is not an ideal situation for all users as, unlike reading a page from top to bottom, the eye is more likely to need to move rapidly when using a screen, which may require head movement when wearing glasses bifocals A more sophisticated solution is progressive addition lenses which, instead of simply splitting into two lens powers, gradually increase the power moving from the top of the lens to the bottom. This allows for easier adjustment to different types of visual material.
Glasses that are only used for reading are usually made of cheaper materials.
