What is the shape of a lens when focusing on objects far away and objects up close?

The ciliary muscle, responsible for changing the shape of the lens, adjusts its tension to focus on different distances. When focusing on objects far away, the lens needs a large focal length, so the muscle is relaxed in order to make the lens relatively flat. When an object is closer to the eye, however, a shorter focal length is needed. The ciliary muscle contracts, reducing the focal length of the lens by making it more spherical. The process of adjusting the shape of the lens to focus in on objects is called “accommodation.”


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