Question

Explain why objects are seen more dearly at night by not looking directly at them?

Answer 1

When looking directly at an object, light reflected from it passes along the optical axis of the eye and strikes the retina at the fovea which contains cones only. During day light this will produce a detailed image in the brain due to the high light intensity activating the cones. At night the light intensity would be too low to activate the cones. By looking slightly to one side of the object the reflected light from it will not strike the fovea but a point on the retina to the side of it where there are rods. At night these will be activated by the low light intensity and an image will be produced in the brain.