If you wear glasses, it’s likely that you’ve been given a prescription with a number of different measurements and abbreviations. One of these measurements is the “plano sphere,” which is used to correct for nearsightedness or farsightedness. But what is a plano sphere for glasses refers to, and how does it affect your vision? Here’s what you need to know.
What is the Plano Sphere?
The plano sphere, also known as the dioptrical power of a lens, is a measurement that tells your optometrist how strong your prescription needs to be. This measurement is given in units of diopters (D), which is the inverse of the focal length in meters. In other words, the higher the number of diopters, the stronger the lens will be.
What is plano sphere lenses?
Plano Sphere Lenses are custom-made progressive nearsightedness, hyperopia or heterophoria (reading errors) corrective lenses. They provide unlimited reading power and eliminate the need to switch back and forth between two different pairs of glasses.
The vast majority of people who need corrective lenses have either nearsightedness or farsightedness. Nearsightedness, or myopia, is caused by an elongated eyeball or a cornea that is too curved. This results in light being focused in front of the retina rather than on it, which causes distant objects to appear blurred. On the other hand, farsightedness, or hyperopia, is caused by a shortened eyeball or a cornea that isn’t curved enough. This causes light to be focused behind the retina, resulting in close objects appearing blurry.
How Does the Plano Sphere Affect My Vision?
The plano sphere measures the curvature of your eye and determines how much correction is needed in order to give you 20/20 vision. If you have nearsightedness, you will need a negative prescription (-), whereas if you have farsightedness, you will need a positive prescription (+).
For example, let’s say that you have a plano sphere measurement of -2.00D. This means that your eyeball is 2 meters longer than average or that your cornea has too much curve. As a result, you will need a corrective lens that is 2 diopters weaker than average in order to see clearly. On the other hand, if you have a plano sphere measurement of +2.00D, this means your eyeball is 2 meters shorter than average or that your cornea doesn’t have enough curve. As a result, you will need a corrective lens that is 2 diopters stronger than average in order to see clearly.
The final thoughts
A negative plano sphere indicates nearsightedness while a positive plano sphere indicates farsightedness. Most people fall somewhere within the range of -6.00D to +6.00D; however, some people may require stronger or weaker corrective lenses depending on their individual situation. If you have any questions about your plano sphere reading or what it means for your vision, be sure to ask your optometrist during your next appointment!