Once you have your specific contact lens prescription* from your ophthalmologist or optometrist, buying contact lenses online at Lenstore.ie is very simple — just enter the parameters from your prescription after selecting your lenses.
Please note that contact lens prescriptions and glasses prescriptions are not the same.
What prescription parameters do I need to enter at Lenstore.ie?
Depending on the type of product, your contact lens prescription may contain between 3 and 7 values.
As you can see in the image below, the 3 most common values (in addition to the expiry date) are:
- The Sphere or Power (SPH / PWR): Sphere or Power is a measure of the optical strength of a contact lens, equivalent to the reciprocal of one metre. It can be positive (longsightedness / hyperopia), negative (shortsightedness / myopia), or 0.00 (no correction, also known as ‘Plano’ or ‘neutral’).
- The Base Curve (BC): The base curve is the internal curvature of the contact lens, typically between 8.3 and 9.0 mm.
- The Diameter (DIA): The diameter indicates the size of the lens in millimetres. Common values range from 13.8 to 14.5 mm.
For astigmatism correction, are there additional parameters to enter?
For toric lenses (used to correct astigmatism), your prescription will also include the following values, as shown in the image below:
- The Cylinder (CYL): The cylinder, always expressed as a negative value, indicates the degree of astigmatism.
- The Axis (AX / AXIS): The axis indicates the angle at which the lens corrects the astigmatism, with a value between 0° and 180°.
For multifocal (progressive) lenses, what additional parameters are required?
- Addition (ADD): The Addition is the extra correction needed for near vision.
- Dominant (DOM): The Dominant value appears only in some multifocal lens types and indicates which is the dominant eye.
What type of contact lenses do I need?
Everyone has different characteristics and needs. To find out which lenses are most suitable for your specific situation, an eye examination is absolutely necessary. Your ophthalmologist or optometrist will be able to advise you on which type of lenses to use and will issue a prescription with all the parameters you need to order.
How do I get a contact lens prescription?
If you are buying contact lenses for the first time, you will need a prescription that provides the essential parameters to complete your order on Lenstore.ie. The prescription is issued by your ophthalmologist or optometrist following an eye examination.
If you already wear contact lenses, you can simply copy the parameters from the side of your lens box and proceed directly to purchase.
* It is important to note that contact lens prescriptions and glasses prescriptions are not the same. The values on a glasses prescription are not compatible with contact lens parameters and cannot be used interchangeably.
Also please note that your prescription should not be more than one year old, as your parameters may change over time.