Optical MathCâu 96 / 100
A patient is refracted at a 12 mm vertex with -10.00 D, but the frame sits at 16 mm. Which way does the effective power change, requiring compensation?
a.Toward more minus, so less minus is ordered
b.The lens must gain minus power
c.No change occurs
d.It becomes plus power
Giải thích
Moving a minus lens farther from the eye (12 to 16 mm) increases its effective minus power, so a slightly weaker (less minus) lens is ordered to keep the correction accurate at the new vertex distance.
Luyện miễn phí toàn bộ 100 câu hỏi — không cần đăng ký.
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