Description
Designed to measure Anisophoria which is the change in the phoria away from the primary position.
Small Aperture Maddox Phoria Measure combines large 25mm aperture, a red maddox mounted perpendicular to the handle in a 10PD prism in a rotating disc with knurled edge. Small indicator in the periphery of the disc to indicate the effective prism power from 0PD to 10PD.