The main strength. Minus means short-sighted (distance is blurry). Plus means long-sighted.
Correction for astigmatism. CYL is the strength, AXIS is the angle from 1 to 180. If CYL is blank, you have no astigmatism to correct.
Extra reading power for varifocals, bifocals or reading glasses. Your reading strength is roughly your SPH plus the ADD.
The distance between your pupils in millimetres, usually 54 to 74 for adults. It is often not written on the prescription, but you can ask your optician or measure it with a ruler and a mirror.
No. Contact lens prescriptions are different and cannot be used for glasses.
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