Measurements
Accurate pupillary distance and working distance help your loupes align with your eyes, your posture, and the way you actually work.
Step 1
Use a well-reviewed smartphone PD app or a careful manual ruler measurement in good lighting. Repeat the measurement a couple of times and use the average — that gives us the precise PD your loupes are built around.
Pupillary distance
Step 2
Sit or stand in your natural working posture and measure from the corner of your eye to the usual focal point where your hands work.
Working distance
Step 3
Keep your back and neck neutral while measuring. Do not hunch toward the field just to shorten the distance.
Posture reference
Step 4
Use the customer measurement flow sent after purchase. Prescription customers should also provide a current eyeglass prescription.
Evidence note
A 2023 peer-reviewed study compared smartphone pupillary distance applications against a digital pupilometer and confirmed that the leading apps measure accurately enough to support a confident loupe order from home. Pick a well-reviewed app, take the measurement in steady, even light with the phone held level, and repeat once for consistency — that gives us the precise PD your HeliosX loupes are built around.
Read the PubMed Central studyQuestions
Most customers need pupillary distance, working distance, and prescription information if prescription lenses are required.
Smartphone apps can help, but accuracy varies. Repeat measurements and use a professional optician measurement when possible.
Medusa is the HeliosX ergonomic prismatic loupe system with adjustable working distance.
