What characterizes biconvex lenses?

Biconvex lenses are characterized by being thicker at the center compared to the edges. This shape causes light rays that pass through the lens to converge towards a focal point on the other side. The curvature of the lens surfaces allows it to bend incoming parallel light rays inward, making them converge at a specific focal distance. This is a fundamental property of converging lenses, and biconvex lenses are a common example used in various optical applications, such as magnifying glasses and cameras.

In contrast, options that describe a lens as thinner at the center (which would result in light diverging) or having uniform thickness or flat surfaces do not accurately depict the properties of biconvex lenses. Such characteristics are associated with other types of lenses, like concave lenses (which diverge light) or plano-convex lenses (which may have a flat side). Understanding the properties of biconvex lenses helps in grasping how they function to focus light and form images.