What Makes the Human Eye Separate Close Objects?

The eyes are our most important sensory organ, as we rely on our sight more than any other sense. The eyes can see things far away and can focus in on minuscule objects. They can also differentiate between very small objects, even when they are close together. Learning about the basic anatomy of the eye can help you better understand this phenomenon.

Eye Design

• The eye consists of many small parts that help create "vision." These include the iris, the lens, the pupil, the cornea and the retina.

Eye Function

• The eye "sees" as light rays reflect off an object and then enter through the cornea. These rays then pass through the lens, which is pliant and capable of changing shape so it can "bend" the rays. The lens then imprints the rays on the retina, located at the back of the eye, and the light is converted to images by the brain via millions of nerve cells called rods and cones.

Rods and Cones

• Rods are located around the perimeter of the inside of your eyeball and allow for peripheral vision, motion detection and night vision. Cones are in the center and help us focus and create clear images.

Focus

• When we need to focus on something near or small, the ciliary muscles around the eye tense, which causes the lens to become more rounded and reflects the light rays onto the cones of the eyes. This limits peripheral vision but increases clarity.

Clarity

• Increased clarity helps us delineate the specific details that allow us to tell close objects apart.