A plano-convex lens is made of a material with a refractive index of 1.5 . If the radius of curvature of its curved surface is 25 cm , what is the power of the lens?

Step-by-step solution

According to the Lens Maker's formula, the focal length f is given by: 1 f = ( - 1) ( 1 R₁ - 1 R₂ ) For a plano-convex lens, the radius of curvature of the curved surface is R₁ = +25 cm = +0.25 m , and the plane surface has an infinite radius of curvature, so R₂ = . Substituting the given values: 1 f = (1.5 - 1) ( 1 0.25 - 1 ) 1 f = 0.5 4 = 2 m ⁻¹ The power of the lens is P = 1 f (with f in meters). Therefore, P = +2 D . Answer: +2 D