How To measure PD Pupillary Distance?

What is Pupillary Distance (PD)?

Pupillary Distance (PD) is the measurement (in millimeters) between the centers of your pupils. It ensures that your prescription lenses are perfectly aligned with your eyes, improving visual clarity and comfort. An accurate PD measurement is crucial for single-vision, bifocal, and progressive lenses.

How to Measure Your PD at Home

You can measure your PD easily using a mirror and a millimeter ruler. Follow these simple steps:

Method 1: Using a Mirror

1. Stand in front of a mirror – About 8 inches (20 cm) away.
2. Hold a millimeter ruler – Place it on the bridge of your nose, aligning it with your eyes.
3. Close your right eye – Align the 0 mm mark with the center of your left pupil.
4. Close your left eye and open your right eye – Read the measurement at the center of your right pupil.
5. Repeat the process – To ensure accuracy, measure 2–3 times and take the average.

Method 2: With a Friend’s Help

1. Sit still and look straight ahead.
2. Your friend should align a ruler across your eyes, resting on your nose bridge.
3. Measure from the center of one pupil to the center of the other.
4. Confirm the accuracy by measuring multiple times.

How to Get Your PD from Your Prescription?

Your optometrist may include your PD in your prescription. It is usually written as a single number (e.g., 62 mm) or two numbers (e.g., 30/32 mm) for each eye.

• Single PD: One measurement for both eyes.
• Dual PD: Separate measurements for each eye (useful for progressive lenses).

Why is PD Important?

• Proper lens alignment for clear vision.
• Essential for progressive & bifocal lenses.
• Prevents eye strain and discomfort.

At HAIOP, we ensure your lenses are crafted with precision. If you need assistance with your PD measurement, feel free to contact us!