How eyes make sense of the world

Human eyes can’t decipher individual pixels from far away—this video shows why.

How does the eye work exactly? In the latest video from Decoder, learn some of the extraordinary science behind how your eyes and brain work together to perceive the world around you.

For more, read ‘How Eyes Make Sense of Pixels’ in the October 2018 issue of National Geographic Magazine.

How eyes make sense of the world

Human eyes can’t decipher individual pixels from far away—this video shows why.

How does the eye work exactly? In the latest video from Decoder, learn some of the extraordinary science behind how your eyes and brain work together to perceive the world around you.

For more, read ‘How Eyes Make Sense of Pixels’ in the October 2018 issue of National Geographic Magazine.
A version of this story appears in the October 2018 issue of National Geographic magazine.

Short for “picture element,” a pixel is one of many tiny, illuminated squares on a digital display. A smartphone screen contains thousands of pixels, so densely packed that they seem to disappear inside a smooth, vivid image. But packing pixels is necessary only for up-close viewing. A digital billboard can have fewer pixels than a smartphone yet still appear seamless from afar because the human eye can’t perceive individual pixels from great distances.