A spectacle prescription can look like a row of unfamiliar abbreviations. Each value describes an optical correction, but the numbers are only one part of comfortable vision.
Sphere and the sign
Sphere describes the main focusing power in dioptres. A minus sign commonly indicates short-sighted correction and a plus sign commonly indicates long-sighted correction. Right and left eyes may have different values.
Cylinder and axis
Cylinder describes the amount of astigmatism correction. Axis, measured from 1 to 180 degrees, states its orientation; it is not a strength. If no cylinder is required, an axis may not be listed.
Add and other measurements
An add value supplies extra plus power for near tasks in multifocal or reading lenses. Prism, pupillary distance and fitting measurements may also appear. Do not compare prescriptions without considering the examination, visual needs and lens design.
A clear next step
Write down what you have noticed, when it began and which activities are affected. That simple record can make a professional conversation more focused and useful.