Understanding Your Eye Prescription

Understanding Your Eye Prescription


Understanding your eye prescription can be challenging. Here, at Bellevue Eye Specialists, we want to clarify any inquiries you have regarding your eye prescription, to make your glasses/contacts lens experience the best it can possibly be.


Sample Prescription:











Where To Start

Your prescription consists of a few measurements that collaboratively help our lab to create the right lens for you. Here is a brief explanation on what each one of those measurements mean:

  1. Sphere: The Length of Your Eyes
    • Myopia (-): The negative sign in front of the spherical measurement signifies the individual’s eye is longer than a normal eye. As a result of this, a myopic person can see clearly near them, but cannot see clearly at a distance.
    • Hyperopia (+): The positive sign in front of the spherical measurement signifies the individual’s eye is shorter than a normal eye. As a result of this, a hyperopic person can see clearly at a distance, but might have trouble seeing at near distances.

2. Cylinder: The Shape of Your Eyes

Our eyes are normally shaped to be evenly spherical in all directions. Sometimes over time, due to genetic reasons or other medical reasons, our eyes can change in shape.

Typically with astigmatism, our eyes turn from being an even spherical shape to an oval “football” shaped eyeball. Astigmatism is common and can be easily corrected through proper corrective vision.


3. Axis: The Direction the Corrective Power Is Adjusted To

The axis measurement is the direction that the corrective vision power is adjusted to.

4. ADD: Optional Reading Power

The ADD power determines if you need a pair of single vision (SV) or progressive/bifocals, in addition to your corrective distance power. As we age, it is common for many individuals to need a pair of bifocals/progressives to aid for reading, regardless of their distance vision. Ask your doctor if you have any questions regarding using or switching to a pair of bifocals/progressives.


These are some basic explanations on how your eye prescription works. Eye prescriptions are independently catered to a specific individual and should be updated every 1-2 years with an optometrist. If you have any specific questions, please feel free to schedule an appointment with one of our experienced doctors.

If you need any glasses adjustments, we at Bellevue Eye Specialists are more than willing to help you adjust your glasses properly. Call us today to schedule an appointment!


Cited Sources:

Boyd, K., & Edmond, J. (2018, September 07). What Is Astigmatism? Retrieved June 27, 2020, from https://www.aao.org/eye-health/diseases/what-is-astigmatism

Boyd, K., & Satterfield, D., MD. (2018, April 04). Farsightedness: What Is Hyperopia? Retrieved June 27, 2020, from https://www.aao.org/eye-health/diseases/hyperopia-farsightedness

Tubert, D., & Pagan-Duran, B., MD. (2020, May 15). Nearsightedness: What Is Myopia? Retrieved June 27, 2020, from https://www.aao.org/eye-health/diseases/myopia-nearsightedness