Here are two ways you can measure your PD:
Remember you can always go to an eye care specialist locally and for a small fee have them measure your pupillary distance for you.Or you can ask for your PD measurement at the time of your eye test, new measurements may require a charge, old measurements can be given out to you as your records that you have paid for.
The Federal Trade Commission (FTC) has issued a rule regarding the handling of spectacle prescriptions. The latest iteration is often referred to as, "Eyeglass II" (CFR 456). The text of that rule states, "The prescription shall contain all of the information necessary to permit the buyer to obtain the necessary ophthalmic goods from the seller of his choice. the accuracy of the ophthalmic goods and services dispensed by another seller."
These rules may be different state to state some have stated that the PD is part of the RX, generally opticians and ophthalmologists(M.D.'s) may charge while OD's (optometrists) may not.
Your Pupillary Distance (PD):
This is the measurement between the
center point of your pupils.
This measurement is easily taken by looking at your reflection in the mirror; or by asking a friend /relative to measure for you if it's not included on your prescription.
Why is your pupillary distance measurement so important?
The pupillary distance is the optimal space on your eyeglasses that gives you the best and truest vision. It is the "optical center" of your prescription lens, and which is found right in the front of you with both eyes looking forward. The optical lab needs this information so that when making your custom lens they can know where "your" optical center would be.
You can also measure your PD using this method:
- Wear your glasses. (Or any glasses if you don't have your own. A pair of sunglasses will do fine.)
- Using a felt tip marker or some sticky dots/scotch tape.
- Focus on a single object in the far distance (anything farther than 20 feet works, but farther is better).
- Raise the marker to your right lens and precisely put a dot on it directly over the distant object; you can also make crosshairs on the scotch tape
- Repeat for your left eye. If done correctly, with both eyes open the two dots should overlap into a single dot over the distant object. If not repeat making the markings until they do form a single dot/crosshairs.
- Measure the distance between the two dots on your lenses with a millimeter ruler.
- That's your distance PD.
- If you need a near PD for reading or computer glasses, just do the same procedure but focus instead on the object you will be looking at, either reading material (at a comfortable reading distance )or computer monitor which is usually about 17" - 20" away from your face.