Prescription AnalysisQuestion 53 of 100
When both eyes require decentration for a smaller PD than the frame, the optical centers are moved which way?
a.Temporally (outward)
b.Vertically only
c.Nasally (inward)
d.Not at all
Explanation
When the patient's PD is smaller than the frame's distance between lens centers, the optical centers must be decentered inward (nasally) to line up with the pupils and avoid unwanted prism.
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