Reading glasses are being sold in shops and even pharmacies. The important question is, what are the long-term effects of using these glasses? Can you use them safely and without damaging your vision?
The answer will surprise you. Reading glasses magnify images and text by linear magnification. No correction takes place since the lens only magnifies the image. Many people have a form of corrective error, especially the elderly. If the prescription glasses don’t incorporate this error, the uncorrected error will be magnified by linear magnification. This would in turn cause eye strain. It could even lead to accelerated deterioration of vision.
Everybody who needs reading glasses does not have the same prescription. Some reading spectacles may offer very high magnification while others, weak. Just because the reading spectacles you bought from over the shelf magnifies text and images that does not mean that it is the correct one for you. The reading correction has to be balanced for both the eyes and the magnification rendered must be exact so that it does not damage vision.
Off the shelf glasses cannot be compared in clarity to those prescribed by an optometrist. They may be used for the short term but they are not the answer to your vision problems.
Particularly, after you are well into your 40’s you should have your eyes checked every 2 years. After this age, many people develop vision problems and their eyes’ start losing the ability to focus. This condition is called presbyopia. You might be tempted to buy a readymade pair of reading glasses but this is the time to visit an eye specialist. The doctor will diagnose your problem correctly and suggest corrective measures to preserve your vision. You can even invest in prescription sunglasses that offer both style and functionality.