Presbyopia degree changes in a regular pattern with age!
Reading glasses have a prescription, and the prescription changes in a regular pattern, increasing with age. Generally, it increases by 50 degrees every five years, and the prescription usually doesn't change much after age 60. You can refer to the image above for the changes in prescription.
Easy self-test for presbyopia!
Want to know the approximate prescription of your reading glasses? All you need are: reading glasses, a piece of cardboard, a ruler, and sunlight.
Instructions: Hold the lenses perpendicular to the sunlight, and place the cardboard behind the glasses.
Focusing: Move the cardboard to find the smallest, brightest point of light. Measurement: Measure the distance from the point of light to the center of the lens. This equals the focal length (in meters).
Calculation: Presbyopia prescription ~ 100 ÷ focal length (meters) (This method provides an approximate value; for a precise eye exam, please visit a professional optician!)
Wear your glasses when you need to! Don't tough it out on your eyes.
If you already have presbyopia, forcing yourself not to wear reading glasses will definitely worsen your ciliary muscle's strain, making reading difficult, causing fatigue and an inability to adjust your vision, as well as many symptoms such as dizziness and eye strain, affecting your life and work. This is very unwise. Therefore, get reading glasses as soon as you need them; don't delay. Also, replace your original reading glasses when the prescription becomes insufficient as you age.
We will attend the 2026 MIDO Optical Fair on Jan.31~Feb.2 ,welcome to our booth. You can know our products first, please check which items you are interested in and contact us freely. Now Summer is coming, Our photochromic lenses are hot sale , please find more details form our website. we also have RX preceitpion lens and so on.
Post time: Dec-19-2025