Question

What is power of accommodation of the eye of a person?

Answer 1

Step 1: Functioning of the eye lens

1. The ciliary muscles help to keep the crystalline double convex lens in place. The ciliary muscles, together with the suspensory ligaments, may change the curvature of the eye lens, and hence the focal length required to focus objects on the retina which are placed at distinct distances.
2. It is the adjustment of the focal length of the eye lens with the help of ciliary muscles which enables us to focus on objects situated at distinct distances.

Step 2: Power of accommodation

1. One of the remarkable properties of the eye is the ability to observe distinctly the objects located anywhere from about 25 cm to a large distance. When the lens focuses light from an object to form a real and inverted image (of the object) on the retina, we are able to see that object.
2. The focal length of the eye lens is 'adjustable' as it can be changed to some extent by the ciliary muscles.
3. Thus, the power of accommodation refers to the ability of the eye lens to alter its focal length in order to see objects placed at different distances.