How many curves does a spherical lens contain?

A spherical lens contains one curve, which is consistent across the entire lens surface. This single curvature allows light to converge or diverge uniformly across the lens, providing consistent optical power for vision correction. Spherical lenses are designed to correct spherical aberrations and overall refractive errors in patients' vision.

In contrast, other types of lenses, such as toric lenses, feature multiple curves to address astigmatism, while other designs may incorporate additional complex curvatures. However, a basic spherical lens retains that singular characteristic of having just one curve, making it a fundamental element in optics and contact lens design.