lens power supply?, The unit of lens power is measured in diopters (abbreviated as “D”). The diopter is the unit used to indicate the refractive power of a lens. It indicates how much a lens deflects light as it passes through the lens.
Eyeglasses use lenses to correct refractive problems such as nearsightedness (myopia) or farsightedness (farsightedness). If someone is nearsighted, it means that the light is focused in front of the retina instead of exactly on the retina. A negative diopter (eg -2.00 D) is used to correct myopia.
If someone is farsighted, it means the light is focused behind the retina. In this case, a positive diopter (eg +1.50 D) is used to correct the farsightedness.
Additionally, lenses may also have cylinder and axis values to correct for astigmatism, a condition in which the eye has two different refractive powers, usually in two different axes. These additional values are indicated in diopters and degrees.
It is important to know that the prescription of contact lenses is the work of a qualified ophthalmologist or optometrist. They will determine the correct force unit and any additional corrections based on an eye exam.