What’s the Difference Between a Contact Lens and a Spectacle Prescription?

You’ve had your eyes tested and need glasses but want the freedom of contact lenses. You want to order some lenses, you’ve got your spectacle prescription in hand so can just jump on and order some lenses, right? Wrong!

To wear contact lenses, you MUST be fitted with them by a qualified eye care practitioner.

Why?  There are many reasons for this, one being that a contact lens sits on the actual surface of your eye and not a distance away, as your glasses do, so the power of the lens you require can be different, but there are many other reasons…

What happens at a contact lens fitting appointment?

During your contact lens fitting appointments your eyes will be checked to make sure they are suitable for contact lenses, don’t worry, almost everyone can wear contact lenses, whether you have dry eyes, need to correct an astigmatism or even normally wear varifocal glasses, there is a lens available for you.

There are also various other checks that your eye care professional will carry out during a contact lens fitting and you will be shown how to handle your lenses, apply and remove them.

Once your optician is happy, you will be sent home with some lenses to trial and then asked to return to the practice to complete your fitting. Once you have had this second appointment, and completed your fitting, you are then issued with your contact lens prescription. Also known as a contact lens specification.

You may find that your contact lens prescription looks quite a bit different to your prescription from your eye exam. This is due to extra information being on your contact lens prescription and the numbers, are likely to be different too. This then enables you to purchase your lenses.

What are the differences between a spectacle prescription and contact lens prescription?

You will probably be familiar with the below, this is an example of what your spectacle prescription will look like…

A contact lens prescription is ever so slightly different. Yes, it will have some of your personal information on, like your name, address, date of birth, but from the example below you can see that there are some differences…

The first difference you will notice is that the lens type you have been fitted with will be shown on here. It may be that it tells you the name of the lens or even go into more details to give you such information as to the brand or manufacturer too.

It will show you the power or sphere of the lens you require to wear and some other information that you may not be familiar with, lets de-bunk these for you: –

Base Curve – This is one of the lens measurements and is the curvature of the lens.

Diameter – yes, as in a circle, this is the width of the lens.

Both the base curve and the diameter maybe shown together, or separate and may even be covered in the specification part of your prescription with the lens power or could even be called parameters, depending on your opticians.

Similarly, to your spectacle prescription your contact lens prescription will be dated and there will be an expiry date too. This is when you will need to visit your optician to have an aftercare appointment/check-up. And finally, your opticians’ details will also be on your contact lens prescription.

So now you know the difference between your glasses and contact lens prescriptions and why you need to be fitted by an eye care professional with contact lenses to purchase them.

How can Superdrug support you?

If you are new to contact lenses you can always find out more on our dedicated contact lens online page on how to become a contact lens wearer. Not sure if they are for you? Find out how out customer, Tanya, got on when she tried contact lenses in: A Diary of First Time Contact Lens Wearer. 

For more information on ordering contact lenses and contact lens aftercare, visit Superdrug Contact Lenses Online.

We look forward to seeing you and your contact lens prescription soon.

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