The vision of an eagle is considered to be a type of sharp and keen eyesight known as "far-sighted vision" or "distance vision". Eagles have a very high concentration of light-sensitive cells in their eyes, called cones, which enables them to see with great clarity and detail over long distances. They also have a wide field of vision, which allows them to detect even the slightest movement from prey or potential threats. Additionally, eagles have a special protective structure on their eyes called the nictitating membrane, which helps to protect their eyes while hunting and flying at high speeds.