Optical MathQuestion 91 of 100
Using Prentice's rule, how much prism is induced when a +4.00 D lens is decentered 5 mm?
a.1.0 prism diopter
b.2.0 prism diopters
c.20 prism diopters
d.0.5 prism diopters
Explanation
Prentice's rule: prism (prism diopters) = decentration (cm) x power (D). 5 mm = 0.5 cm; 0.5 x 4.00 = 2.0 prism diopters.
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