The reading glasses without a prescription are similar to those prescribed by a doctor, but the crystals have some differences. Prescription, also called power (a way of estimating crystals) is usually designed in the same way in prescription and non-prescription glasses, but how crystals are made can affect how you see through them. If you know the basic differences between the two types of lenses, you can buy your reading glasses with confidence.
Calculate the fit of the frames. Look for frames that fit comfortably. Try several pairs until you have a good idea of what suits you. Frames must fit correctly over your nose and not slip. The arms, also called sideburns, should fit gently behind your ears and have enough length to prevent frames from slipping off your nose.
Calculate the graduation. Find the correct power or grade of crystals you need. If you're not sure, a good rule of thumb is to start with a + 1.00 rating (called a diopter) if you're starting to wear reading glasses. Reading crystals start with + 1.00 and increase in increments of 0.25. The general pattern of graduation according to age indicates use around 40 years of age: +1.00. From 43 to 47: +1.50. From 48 to 53: + 2.00.
Check the graduation of the crystals with some text in small letters. If you have to look at what you read from beyond a comfortable distance, the crystals are very weak. If you have to hold the reading near your face, the crystals are very strong. Try several crystal graduations until you find the one that works best for your vision.
Test the lenses for various types of reading jobs. The reading correction can be used in different ways. You can hold a book to read on your skirt, and this will require some graduation. But you can also use your computer at a different distance, and you will need a different graduation for this type of work. You can have more than one pair of reading glasses with different graduation, depending on what you wear them.
Use the lenses in the store for a few minutes before buying them to see if any distortion develops, problems to see through the lenses or a headache. Since over-the-counter reading glasses are designed as "a model for everyone" and most people have unique prescriptions, wearing nonprescription lenses can become uncomfortable and actually cause problems instead of fixing your vision disorder. Testing and measuring the lenses for a few minutes before buying them helps you avoid spending your money on something you can not use.
advice
Get a copy of the prescription for your vision spectrum made by your eye doctor, even if you do not buy the lenses through it. By law, you have the right to have a copy of your test. Check if you have the same graduation in both eyes. Over-the-counter lenses are made with the same graduation on both lenses and work best for people who have this type of prescription.
Warnings
If you have large astigmatism (any value above 0.50), reading glasses without prescription will cause eye strain. Most people have some astigmatism correction (written as CYL or cylinder in your prescription). Over-the-counter reading glasses are made only with graduation for distance and are not designed to correct astigmatism.
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