cat eye

[mark_lansch]

how can cats see in dark?

[potterfan3]

they have things in the back of they eyes that reflect light like a mirror and it reflects light from faw away, thats why there eyes glow, it is they same for a lot of noctornul animals

[drgnrdr]

Potterfan3 has almost got it, here's better details: Cats have both rods and cones in the retina. Rods are the receptors that the eye uses for night time viewing and sudden movement. Cones are used during the daytime, and process color information. Cats have more rods than cones, as compared with humans, making cat night and motion vision superior to humans.
In low light, like night, color and hue are not perceived, only black, white and shades of gray.
Cats have an elliptical pupil which opens and closes much faster than round types and allows for a much larger pupil size. This allows more light to enter the eye. Cats also have a mirror like membrane on the back of their eyes called a Tapetum. It reflects the light passing through the rods... back through the rods a second time, this time in the opposite direction.
The result is a double exposure of the light, which permit cats to see well in near darkness.
Although a cat cannot see in total darkness, a partly cloudy night sky with some stars will provide enough light for cats to hunt and see movement, even in the cover of most brush. At night, a cat relies on it's extremely sensitive hearing and directional ear movement to locate the general position of prey, then targets and captures the prey using it's keen eyesight.
The yellowish glow you see when you shine a light into cat eyes at night, is really your light reflecting off the Tapetum membrane.

From video for cats. com