Which of the following materials will yield the greatest front surface power when made with the same radius of curvature on the front surface?

• A. Polycarbonate
• B. Flint glass
• C. CR-39 plastic
• D. Acrylic

Answer: (B)

Flint glass is known for having a higher refractive index compared to other materials listed. The refractive index is a crucial factor in determining the front surface power of a lens. When two lenses have the same radius of curvature, the lens with the higher refractive index will have greater optical power. This means it can bend light more effectively, resulting in a stronger lens for correcting vision.

In the case of the materials provided, flint glass typically has a refractive index in the range of 1.58 to 1.65, which is significantly higher than the refractive indices for the other materials mentioned. Polycarbonate, CR-39 plastic, and acrylic have lower refractive indices, meaning they do not bend light as effectively given the same curvature. Consequently, the power generated from the same radius of curvature will be maximized with flint glass due to its superior refractive properties.