How do I figure out my contact lens prescription?

How do I figure out my contact lens prescription?

You can find your prescription on the piece of paper given to you by your optician during a check-up, on the end/side of your contact lens box or on the blister packs that contain your contact lenses.

What is the cylinder on a contact lens prescription?

Cylinder (CYL) – This indicates the amount of lens power for astigmatism and represents the difference in the greatest and weakest powers of the eye, usually separated by 90 degrees.

What does cylinder DS mean in eye prescription?

DS is short for “Diopter Sphere” and should only be seen in your CYL column. It means there is no CYL correction needed, or in other words, no astigmatism correction.

What is BC and DIA for contacts?

Abbreviated “BC,” the base curve of a lens indicates the curvature on the inside of a lens. Abbreviated “DIA” the diameter of a lens measures the width of a lens in millimeters, from end to end. The average size of a contact lens is between 13.5 and 15 millimeters.

What does the D and CYL mean on contacts?

Diameter (DIA): The diameter of the contact lens is also written in millimeters and determines the width that best fits your eye. Cylinder (CYL): If you require toric lenses to correct for astigmatism, your prescription will include values for Cylinder and Axis.

What is the difference between SPH and CYL?

‘Sphere’ is basically a measure of how strong your prescription needs to be. The number marked ‘axis’ describes the orientation of astigmatism. It will be a number between 1 and 180. The number under ‘cylinder’ provides the lens power needed to correct the astigmatism.

What number is a bad astigmatism?

75 and 2 diopters is considered mild astigmatism. Between 2 and 4 diopters is moderate astigmatism, and 4 or more diopters is considered significant or “bad” astigmatism. Generally, eyes with 1.5 diopters of astigmatism or more require correction.

What is the difference between glasses prescription and contact lens prescription?

So a -4.00 glasses prescription is roughly equal to a -3.75 contact lens prescription. You can do the same for astigmatism correction, though it only becomes relevant if the glasses astigmatism is at least -0.75 to -1 diopters (otherwise combine cylinder and spherical from the glasses prescription for the contact lens).

What is the cylinder for contact lenses for astigmatism?

Contact lenses for astigmatism only become available at ‘Cylinder’ values of -0.75 or higher. So what happens when the Cylinder on your glasses prescription is -0.25 or -0.50?

Why is there no cylinder in my Prescription for glasses?

Either 1 of 2 things… Generally, if the glasses ‘Cylinder’ is -0.25, it is not included in the contact lens prescription. If the cylinder is -0.50, it is still dropped from the contact lens prescription, but in order to compensate for the missing ‘Cylinder’ eye doctors will adjust the ‘Sphere’ number.

What is the CYL value for contact lenses?

But in most cases depending on the contact lenses, you would choose the CYL value will be available in -1.25 or -1.75 diopters instead of 1.50D. my recommendation for the lower value. With the axis things can get a little tricky even though you made no mistake during the conversion.