Diopters are a unit of measurement used to quantify the optical power of a lens or curved mirror. A positive diopter value corrects farsightedness, while a negative value corrects nearsightedness.
Your eyeglass prescription will include a sphere (SPH) value measured in diopters. The higher the number, the stronger the correction needed.
Your prescription may also include a cylinder (CYL) value which corrects astigmatism, and an axis value indicating the angle of the correction.
As you age, you may need an ADD (addition) value for reading, typically required after age 40 due to presbyopia.
Understanding your diopter measurements can help you make informed decisions about your eyewear. Your optometrist at Central Optical can help you choose the best lens options.