The retina of our eye has a large number of light-sensitive cells. There are two kinds of light-sensitive cells on the retina : rods and cones. (i) Rods are the rod-shaped cells present in the retina of an eye which are sensitive to dim light. Rods are the most important for vision in dim light … Read more
The iris controls the amount of light entering the eyes. The iris automatically adjusts the size of the pupil according to the intensity of light received by the eye. If the amount of light received by the eye is large (as during the day time), then the iris contracts the pupil (makes the pupil small) … Read more
The optical instruments such as cameras, microscopes, telescopes, film projectors and spectacles, etc., work on the refraction of light through various types of artificial lenses (man-made lenses) made of transparent glass. The human eye works on the refraction of light through a natural convex lens made of transparent living material and enables us to see … Read more
