Ranges of measurement: 0 to 25D, minimum: 0.125D graduation up to 5D, 0.25D graduation over 5D to 25D.
Cylinder axis range: 0º ~180º step 1.
Prismatic power range: prism diopter of pattern A: at 1º interval in the range of 0º~5º; prism diopter of pattern B: at 1ºinterval in the range of 0º~20º.
Prism base angle : at 50 intervals in the range of 0º ~180º.
