Prescription Analysis第 40 / 100 题
A binocular distance PD of 64 mm typically corresponds to what near PD range?
a.66 to 68 mm
b.60 to 62 mm
c.64 mm exactly
d.70 mm
解析
Because the eyes converge for near tasks, the near PD is smaller than the distance PD, usually by about 3 to 4 mm total. A 64 mm distance PD is roughly 60 to 61 mm at near.
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