A predator first needs to be able to locate their prey. Both cats and raptors have developed incredible eyes to do just that.
The first thing you might notice is that both sets of eyes are particularly large. Relative to their body size, cats have some of the largest eyes of any local mammal. If humans had proportionate eyes to an owl, our eyes would be as big as grapefruits. These large eyes provide better vision because they can focus a large image on the retina at the back of the eye.
The size is also critically important for hunting in low light conditions. A larger eye can gather more light to make the image clearer. As crepuscular and nocturnal hunters (active at dawn/dusk or at night), both cats and owls can dilate their pupils to allow more light to enter the eye. They also have a higher proportion of rod cells at the back of the eye. These cells specialize in low-light vision. Humans, on the other hand, have more cone cells, which specialize in color vision.
Cats have an additional adaptation that aids their vision in low-light. The tapetum lucidum is a reflective layer at the back of the eye that bounces light back to the retina, giving rods and cones a second chance to be stimulated. A tapetum is common through many different animal groups, but interestingly is rare in birds and completely absent in owls.
Finally, these eyes have a classic predator orientation. Forward-facing eyes provide binocular vision where the same object can be seen with both eyes. That means the brain can calculate depth and give the predator extreme accuracy when reaching out to grab lunch. Contrast that with prey species who have sideways-facing eyes, a large field of vision, and limited depth perception.
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