After completing a minimum of 3 Vision Tests, depending on the confidence level and consistency of your results, you will receive your EyeGlass Numbers (EGN). These are a set of numbers that contain parameters defining refractive error needed for ordering eye glasses.
An example of an EyeGlass Number record looks like:
|PD:||NV Add +2.00|
The EGN may seem familiar to you because they are written in the same format as your eye doctor's prescriptions. Note that Cylinders are expressed in negative Cylinder notation.
- Spherical & Cylindrical values are measured in Diopters and represent components of your Refraction Correction
- Axis represents the angle of the Cylindrical component makes with respect to an imaginary horizontal line through your eye.
- PD corresponds to the Pupillary Distance in millimeters (mm). This is the distance between your two eyes.
- NV ADD is called the near vision add and is needed for persons with Presbyopia.