The Lens is about 16-20D of power and is layered like onion. It adds layers as we age.
There is no nerve or blood supply so it can transmit light without interruption. It’s the size of a large pea.
Responsible for adjusting its focus, much like a camera lens. The process is called accommodation. During accommodation the lens can increase the plus (+) power of the eye up to 10 D or more by becoming more convex.
Its ability accommodate decreases with age. When accommodation no longer allows easy reading or near vision the condition is called Presbyopia.