Human Eye
The human eye is a spherical ball with a diameter of approximately 2.3 cm. The outer covering of the eye is called the sclera. Light enters the eye through the cornea, which forms a transparent bulge on the front surface of the eyeball. The function of the cornea is to refract the light rays entering the eye and to adjust the focal length. Behind the cornea, there is a muscular diaphragm that controls the size of the pupil, known as the iris. The amount of light entering the eye is regulated by the pupil. The retina consists of a large number of light-sensitive cells that get activated upon illumination and generate electric signals. The optic nerve sends these signals to the brain, which interprets and processes the information so that we perceive the objects the way they are. The eye lens forms the real and inverted image on the retina. Optic nerves are of two types:
- Cones: These cells are more sensitive to bright light. They help in central and color vision.
- Rods: These cells are more sensitive to dim light. They help in peripheral vision.
Difference Between Human Eye and Camera
Human Eye and a camera have many similarities that allow both to capture daily life moments, though in different ways. While the human eye is a sensitive sense organ, a camera appears to be a robotic eye with a cornea-like lens and retina-like film. Both aim to focus on the image that is real and inverted.