Which statement is true about the relation between base curve steepness and magnification in high plus lenses?

• A. Steeper base curve results in thinner lens and greater magnification
• B. Steeper base curve results in thicker lens and greater magnification
• C. Base curve steepness does not affect magnification
• D. Base curve less steep reduces thickness

Answer: (B)

In high plus lenses, how steep the base curve is on the back surface directly affects how thick the lens becomes. A steeper base curve means the lens needs more material toward the center to achieve the same overall power, so the lens is thicker. This increased center thickness, combined with the large positive power, leads to greater optical magnification of objects viewed through the lens. So the statement that a steeper base curve results in a thicker lens and greater magnification is the best descriptor of how base curve and magnification are related in these lenses. A flatter (less steep) base curve would yield a thinner lens and less magnification, and magnification does indeed depend on thickness in thick-plus lenses.