eyeglass prescriptions

An eyeglass prescription indicates the specific lens power needed to correct vision. It includes several key measurements: "Sphere" (SPH) denotes the degree of nearsightedness or farsightedness; "Cylinder" (CYL) measures astigmatism; "Axis" specifies the orientation of astigmatism; and "Add" indicates additional magnifying power for reading, usually for bifocals. The prescription is tailored to each eye, with values for the right (OD) and left (OS) eyes. Understanding these components helps opticians create lenses that improve visual clarity and comfort. Always consult an eye care professional for personalized advice and accurate measurements.