(a) Pupil: It controls and regulates the amount of light entering the eye.
(b) Ciliary muscles: These muscles help to modify the curvature and there by the focal length of eye lens to focus the image of the object on the retina.
(c) Iris: It controls the size of the pupil.
(d) Retina: A real, inverted and diminished image of the object is formed on it.
