Barrel distortion is most commonly associated with which sign of spectacle lens power?

Barrel distortion is most commonly associated with which sign of spectacle lens power?

• A. Minus
• B. Plus
• C. Neutral
• D. Unknown

Answer: (A)

Barrel distortion describes straight lines appearing to bow outward toward the edges of the field. This effect is most tied to minus spectacle powers. Diverging lenses tend to magnify the periphery more than the center, so lines bend outward at the edges as the negative power increases. In contrast, plus powers tend to cause pincushion distortion, where lines bow inward. Neutral lenses usually show little distortion.

Barrel distortion describes straight lines appearing to bow outward toward the edges of the field. This effect is most tied to minus spectacle powers. Diverging lenses tend to magnify the periphery more than the center, so lines bend outward at the edges as the negative power increases. In contrast, plus powers tend to cause pincushion distortion, where lines bow inward. Neutral lenses usually show little distortion.