Prescription AnalysisQuestion 36 of 100
A lens is decentered 4 mm from the optical center for a +5.00 D lens. How much prism results (Prentice's rule)?
a.1.0 prism diopter
b.2.0 prism diopters
c.5.0 prism diopters
d.0.4 prism diopters
Explanation
Prentice's rule: prism = decentration in cm x power. 4 mm = 0.4 cm; 0.4 x 5.00 = 2.0 prism diopters.
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