It determines the angle of view that is how close and how wide you can get with the lens. Increasing the focal length makes your subject appear closer and larger. More subject area fits in the frame if shorter the focal length.

How do lens help us?

Light passes through the front of the eye (cornea) to the lens. The cornea and the lens help to focus the light rays onto the back of the eye (retina). ... The lens of the eye helps us to focus but sometimes needs some additional help in order to focus clearly.

What is eye lens and its function?

The lens is located in the eye. By changing its shape, the lens changes the focal distance of the eye. In other words, it focuses the light rays that pass through it (and onto the retina) in order to create clear images of objects that are positioned at various distances.