Here is a typical contact lens prescription:
Eye | Power (sphere) |
BC | Dia | Brand |
OD (Right) | -2.25 | 8.8 | 14.0 | Freshlook Colorblends |
OS (Left) | -3.00 | 8.8 | 14.0 | Freshlook Colorblends |
Eye
OD – Right Eye
OS – Left Eye
OU – Both Eyes
Power, SPH or PWR
A number that measures near or far-sightedness
BC
BC or Base Curve measures the general shape of the lens, the radius of the sphere of the back of the lens.
DIA
Dia or Diameter measures the width of the lens
BRAND
The manufacturer and brand name of the contact lenses being prescribed. The color of lens does not need to be specified.
Toric (Astigmatism correcting) lenses will also contain two additional numbers:
CYL
Cyl or Cylinder is a measurement for astigmatism
AXIS, X
Direction of a cylindrical lens, a measurement for astigmatism
Bifocal contact lenses generally contain one additional number which is the add power. A special field will be given for this number.
Things to remember about your prescription:
A contact lens prescription is not the same as an eyeglass prescription. In addition to the lens power, your contact lens prescription contains several other pieces of information related to the size of the lens.
Your prescription also contains an expiration date a minimum of one year, or the minimum required by state law, whichever is greater, from the date that the contact lenses were fitted.
BC (base curve) values range from about 8.0 to 9.5. The doctor fits the lens with the curvature most appropriate for your eye. Most lenses come in several different BC values. If your prescription does not contain a BC value, this is likely because your brand of lens only comes in one base curve.
BC values are a bit like clothes sizes – just because you are a BC 8.6 in one brand doesn’t mean you will be in another.
If you are in a toric lens your prescription will contain two additional columns entitled cylinder and axis. These numbers related to the correction of your astigmatism.
The power of a contact lens prescription is generally not the same as an eyeglass prescription. This is because the contact lens sits on the surface of your eye, while your eyeglasses sit about 12 mm in front of your eye