The Eyes of a Cat

The eyes are often said to be the windows to the soul, and the eyes of a cat gleam more than most. The romantic notion that a cat's eyes gleam because they house great power or are otherwise mystical in nature is pretty, but there's actually a very scientific explanation for the mysterious luster you found in a cat's eyes.

Cats are the most efficient gleaners of light. Their pupils can dilate to a full half-inch in width or narrow to an almost-invisible slit. Their eyes can take in as much or as little light as they require to effectively see. This trait allows them to see in almost complete darkness. Contrary to popular belief, they cannot see in absolute darkness; Even their sensitive eyes need some light to make sense of the environment. But they can see their surroundings in great detail with only the smallest bit of light.

Cats are not completely color blind, though they can see red only in the emotional sense. By which I mean red is outside their visual abilities. They also can't see orange, since orange is a combination of yellow and red. They can, however, see striking shades of blue, shades we will probably never be able to appreciate.

Felines are also a little farsighted. In fact, their depth of field is in sharpest focus between 7 and 20 feet. This is not to say that they cannot see things outside this field. They can, but they'll see it in sharper detail if it's inside that range.