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What is the radius of curvature of a one diopter lens?

  1. two plus surfaces

  2. 530 mm

  3. a biconvex lens

  4. +1.75

The correct answer is: 530 mm

A diopter is a unit of measurement for the refractive power of a lens. It is equal to the inverse of the focal length in meters. The formula for calculating the radius of curvature of a lens is r = 1 / P, where r is the radius of curvature and P is the power of the lens in diopters. Therefore, for a one diopter lens, the radius of curvature would be 1 meter or 1000 mm. The other options do not provide the correct measurement for the radius of curvature. Option A refers to the number of surfaces on the lens, rather than the radius of curvature. Option C describes the shape of the lens, not the measurement. Option D provides a different measurement of power, not the radius of curvature. Therefore, option B is the correct answer as it accurately measures the radius of curvature of a one diopter lens.