Question

What is normal human eye? How does eye focus nearer and far off objects?

Answer 1

The distance between the eye-lens and the retina is about 20 mm. When an object is far away from the eye (infinity), the image is located essentially at the focal point. Therefore the focal length of the cornea and the eye-lens should be about 20 mm when the muscles of the eye are relaxed

Answer 2

at the distance of 25 cm normal eye see.