unit force lenses?, Lens power is measured in diopters (D). This is the unit used to indicate the refraction of light from a lens. The lenses are used to correct various eye defects, such as nearsightedness (myopia), farsightedness (farsightedness), and astigmatism.
Myopia is measured with a negative diopter value, for example -2.00 D, while farsightedness is measured with a positive diopter value, for example +1.50 D. The higher the number in diopters, the stronger the lens and the more correction it offers for the particular eye defect.
It is important to note that lens power can vary between left and right eye, and an optometrist or ophthalmologist should perform an accurate eye measurement to determine the correct power for each eye. Wearing the correct prescription lenses is essential for good vision correction and eye health.