Is sph the same as power for contacts? This is a question that often arises when people are shopping for contact lenses. The confusion is understandable, as both terms are used to describe the curvature of the lenses. However, they are not synonymous and have distinct meanings. In this article, we will delve into the differences between sph and power for contacts, helping you make an informed decision when selecting your next pair of lenses.
Sph, which stands for sphere, refers to the curvature of the contact lens. It is measured in diopters (D) and determines how the lens fits over the cornea of your eye. The sph value can be positive or negative, indicating whether you have myopia (nearsightedness), hyperopia (farsightedness), or astigmatism. A positive sph value is used to correct myopia, while a negative sph value is used to correct hyperopia. Astigmatism requires a different type of correction, which is achieved through the use of toric lenses.
Power, on the other hand, is a measure of the corrective strength of the lens. It is also expressed in diopters and is used to describe the strength of the prescription. When you visit an eye care professional for a contact lens fitting, they will measure your vision and provide you with a prescription that includes both the sph and power values. The power value is used to determine the thickness and shape of the lens, ensuring that it provides the correct amount of correction for your vision.
While sph and power are related, they are not the same thing. The sph value is a measure of the curvature of the lens, while the power value is a measure of the corrective strength. It is essential to understand this distinction when shopping for contact lenses, as the wrong combination of sph and power can lead to discomfort, blurred vision, or even eye damage.
When you receive your contact lens prescription, make sure to pay attention to both the sph and power values. If you are unsure about the correct values to choose, consult with your eye care professional. They can provide guidance based on your specific vision needs and ensure that you receive the appropriate lenses for your eyes.
In conclusion, sph and power for contacts are not the same. Sph refers to the curvature of the lens, while power refers to the corrective strength. Understanding the difference between these two terms is crucial when selecting contact lenses, as the wrong combination can lead to adverse effects on your vision. Always consult with a professional to ensure that you receive the best possible fit and correction for your eyes.
