The distance between the two eyes.
You have found the perfect pair of eyeglasses online, but you can’t order them because you don’t know your pupillary distance, a very important prescription parameter. With the following instructions you can easily measure the distance from home.
What is pupillary distance?
The distance between the two pupils from center to center and it is measured in millimeters.
If you want to order a pair of glasses that are only for near distance and you are over 40 years old use the pupillary distance for near vision, which is easily found if you remove 3mm from the pupillary distance for long vision.
Why is the pupillary distance important in the making of glasses?
Each lens that you place in a pair of eyeglasses has an optical center that is defined by the distance between the two pupils of the eyes.
Calculation of pupillary distance
Your prescription may write your pupillary distance, if not, ask a friend for help or use a mirror to calculate it.
- What you will need: ruler & mirror
- Stand 20cm in front of the mirror
- With your face straight, hold the ruler along your eyebrows
- Close your right eye and place the zero in the center of your left pupil
- Looking straight, close the left eye and open the right
- The millimeters that coincide with the center of the pupil of your right eye is your pupillary distance.
Some additional information
- Measure the pupillary distance 3-4 times to reduce the chance of error
- The range of an adult’s pupillary distance ranges from 54mm to 74mm
- The range of a child’s pupillary distance ranges from 43mm to 53mm
Using a friend to measure the pupillary distance
If a friend is measuring your pupillary distance, keep both eyes open and hand the ruler to them to place it along your eyebrows and place the zero in the center of one pupil. The pupillary distance is found by reading the millimeters that are above the center of the other pupil of the eye.
- Keep your eyes still as much as possible
- Don’t look at the person measuring you
- Focus on an object above his/her head about 3-6 m away
- Make sure during the process that your eyes are at the same height
With the pupillary distance and the correct prescription, you can purchase eyeglasses through a valid online optical store Lenshop.eu, saving time and money.