993.971.1: Phoria Measure, 20th Cent.

Additional Images

993.971.1: Phoria Measure.
Image No. 2431 ; Photographer: Helen Kingsley

Object Description

Hand held ‘Monocular Maddox Phoria Measure’ designed to measure Anisophoria which is the change in the phoria away from the primary position. The measure combines a large 25mm aperture, a red Maddox rod disc mounted perpendicular to the integral handle in a 10PD prism which can be rotated from the side by an adjusting wheel. When the handle is vertical, Maddox Rods are horizontal and the patient sees a vertical streak. When the handle is horizontal, Maddox Rods are vertical and the patient sees a horizontal streak. A scale from 0 - 10 prism diopters indicates the measure of imbalance.

Object Classification

Accession Number: 993.971.1
Collection: Ophthalmology
Date: 20th Cent.

Object Dimensions

  • Length: 12.5 cm
  • Width: 4.2 cm

Object Parts

Object Materials

  • aluminium,
  • glass,
  • metal,
  • unidentified coating

Acquisition Detail