What is curvature and focal length in eye lens?

Curvature in the eye lens means how much the surface of the lens is curved, and focal length is the distance where light rays come together to form a clear image.

The human eye works like a camera. The lens inside the eye bends (refracts) light so it can fall on the retina. The amount of bending depends on the curvature of the lens. A lens with high curvature bends light more strongly and has a shorter focal length. A lens with less curvature bends light less and has a longer focal length.

• Curvature: How round or flat the lens surface is.
• Focal length: The distance between the lens and the point where parallel rays of light meet.

In the eye, the ciliary muscles change the curvature of the lens to adjust the focal length. This process is called accommodation. For near objects, the curvature increases and focal length decreases. For far objects, curvature decreases and focal length increases.

So, curvature and focal length in the eye lens are related to how the eye focuses light to form clear images on the retina.