Most people nowadays need some sort of vision correction to see properly. Only in the US, about 61% of the 177 million people need glasses. This makes perfect sense considering all the people that are naturally born with poor vision, age-related deterioration in older people, and all the time we spend using phones and other gadgets, straining our eyes.
Now the problem with glasses is that they are expensive to get, especially in the states, they can range from a couple of hundred dollars to even thousands. And adding the cost of getting a prescription can make getting a new pair of glasses quite expensive. You can save a few bucks by using an older prescription and buying prescription glasses online or in person directly, but how do you use an older prescription to buy new glasses? Is the prescription still valid? Or will a prescription from another country work in the states? We’ll cater to all these questions.
Is there a standard for Eyeglass prescription?
The answer to that question is yes. There is a standard and all optometrists use this when issuing a prescription. No matter where you get your eyeglass prescription from, it can be used to get new glasses but there are a few things you need to know
- You are not required to pay anything extra for the prescription.
- You are not required to buy contact lenses or eyewear with the prescription.
- You are not required to sign anything (such as a release or a waiver) to get the prescription. Although they might ask you to sign a confirmation that they gave you a copy of the prescription.
- Some optometrists tend to leave out some important details (like pupillary distance) from the prescription so that you can only get the pair from them even if you want a new one. Make sure you check whether they mentioned that in the prescription and if not, it’s your right to ask them to add that too.
How long before an eyewear prescription expires?
Even if you have the right prescription, it’s only a matter of time until the prescription cannot be considered valid. If you think your last pair of glasses isn’t right anymore, you should get your eyesight examined, as wearing the wrong glasses can put excessive strain on your eyes.
But other than that, the standard validity period for an eyewear prescription is two years for adults and one year for the rest. Still, it’s always a great idea to get your eyes checked so there’s no chance of you spending money on the wrong pair of glasses.
Can I use an old prescription to get glasses?
Yes and no, the answer is a bit complicated. If you have rather standard eyes with standard corrections required, you can use an older prescription to get a new pair of glasses from a physical shop or online. But sometimes there are far too many variables involved, like your head size and the distance between your pupils, which is used to align the optical center of the lenses to your pupil. This can complicate a few things and it might be hard to find a shop that will use your older prescription and fit the glasses to your head. Buying a non-standard pair of glasses online is even trickier.
Can I use my contact lens prescription for eyewear and vice versa?
The answer is no, contact lens and glasses are completely different as one sits right on your eye and the other is slightly away from your eyes. Hence there are two different tests and measurements involving these two prescriptions.
Understanding an eyewear prescription
Now if you have a proper prescription and it’s fairly standard. You will still need to understand it to buy glasses online as you cannot just show your prescription here like you would at a physical store.
Most stores use the standard terms and the list below should be enough for you to order a pair from most online shops. If your prescription includes anything that’s not mentioned here, you might want some professional to take a look, as you might need some special correction.
Here we have mentioned a few terms and abbreviations that you should know
Oculus Dexter (OD) – Relating to the right eye.
Oculus Sinister (OS) – Relating to left eye.
Sphere (SPH) – power of the lens, a minus sign (-) indicates that it’s for correcting nearsightedness and a plus sign (+) indicates that it’s for farsightedness.
ADD (for bifocals) – if you have presbyopia, then to correct that there is a second focus on the bottom of your lens, this is the lens power for that.
Cylinder (CYL) – relating to astigmatism.
Axis – is the angle of cylindrical power.