What is the diameter of my contact lenses?
The diameter of a contact lens is the width of the lens from edge to edge. It is also expressed in millimetres. This number is usually between 13 mm and 15 mm, though it can be as small as 9mm if a rigid gas-permeable lens, and it determines where the lens will sit in your eye.
What is the difference between 8.4 and 8.6 base curve?
Studies show that a single base curve of 8.4mm managed a “good or better” fit in approximately 90% of individuals,1 and base curves of 8.4mm and 8.6mm together encompassed 98% of individuals….
| LENS | BASE CURVES AVAILABLE (mm) | DIAMETERS AVAILABLE (mm) |
|---|---|---|
| 3 | 8.6 | 14.2 |
| 4 | 8.4, 8.6 | 13.8 |
| 5 | 8.6 | 14.0 |
| 6 | 8.5, 9.0 | 14.2 |
What is BC and DIA in contacts?
BC – Base Curve (usually a number between 8 and 10) DIA – Diameter (usually a number between 13 and 15) Brand – The brand/type of contact lens that your doctor has fitted you for.
What happens if you wear the wrong base curve?
If your lenses have the wrong diameter or base curve, you’ll likely feel that something is always in your eye. If the lenses are too flat, your eyelids will tend to dislodge them when you blink. The wrong size lenses can even cause an abrasion of your cornea.
What is the smallest contact lens diameter?
The smallest sclerals are approximately 14.5 mm in diameter, and the largest can be up to 24 mm. Lenses that are 18 mm or smaller are subcategorized as mini-sclerals.
What is the smallest diameter for contact lenses?
How do I know my contacts are too big?
If your eye is shaped flat like a plate, and you wear a contact lens that is shaped like a bowl, the lens is going to fit too tight. You will feel the edge of the lens where it rests on your eye, your eye may become red as the day progresses, and you may develop inflammation.
