Question

What kind of lens is there in our eyes?
A) concave
B) convex
C) Plano-concave
D) plano-convex

Answer 1

Hint: The human eye produces real images and the cornea is in the shape of a curved surface. It focuses the light rays to the pupil and that hits the lens of the eye. This light ray focused will hit the retina at the back of the eye and form a real image.

Complete step by step answer:
The human eye acts like a convex lens and it always produces real image only. The lens of the human eye is transparent and convex in nature which helps in focusing the light along with the cornea on the retina at the back so that real images will be formed.

So, the correct answer is “Option B”.

Additional Information: The human eye is very complicated in which only a few structures in the eye are important to form a real image. The cornea is a thin, clear membrane which covers the outer part of the front eyeball. The cornea is a curved surface and acts like a convex lens. It begins to focus the light rays. The light rays then pass through the pupil and hit the end of the eye. The lens, also convex, further focuses light so that it will hit retina at the back of the eyeball. At this stage, the retina sends signals to the brain about the image and thus we can see the image.

Note: Our human eye has a size that is limited which makes us unable to gain much light gathering power. Also, the human eye has limited frequency response, since it can only see electromagnetic radiation in the visible wavelengths. The eye performance decreases when we age slowly. This is the reason old people use bifocal lenses to read and see things.