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The biggest difference between human vision and cat vision is in the retina.
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Cats cannot perceive colors as well as humans and cannot see far.
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However, cats have a superior ability to see in the dark compared to humans.
What do cats see behind those reflective eyes?
About a decade ago, artist Nickolay Lamm consulted three animal vision experts to visually represent how cats see the world compared to humans.
The biggest difference between human vision and cat vision is in the retina, a layer of tissue at the back of the eye that contains cells called photoreceptors. Photoreceptors convert light rays into electrical signals that are processed by nerve cells, sent to the brain and translated into the images we see.
The two types of photoreceptor cells are known as rods and cones. Rods are responsible for peripheral and night vision. They detect brightness and shades of gray. Cones are responsible for daytime vision and color perception.
Both cats and dogs have a high concentration of rod receptors and a low concentration of cone receptors. Humans have the opposite, so we can’t see well at night, but we can perceive colors better.
But Lamm wanted to give people the chance to see the world through the eyes of their favorite pets. In the images below, the human view is at the top and the cat view is below.
visual field
Visual field refers to the area that can be seen when the eyes focus on a single point. It includes what can be seen from the front, from above, from below and from the side. Cats have a slightly wider field of view of 200 degrees compared to the average human field of vision of 180 degrees.
visual acuity
Visual acuity refers to the clarity of vision. The average person’s visual acuity is 20/20. A cat’s visual acuity ranges from 20/100 to 20/200 which means a cat has to be at 20 feet to see what the average human can see at 100 or 200 feet. That’s why the bottom picture is so blurry.
color vision
There is a common misconception that cats cannot see any color and only see the world in shades of gray. Humans are known as trichromats, meaning they have three types of cones that allow them to see red, green and blue. Cats are also thought to be trichromats, but not like humans. A cat’s vision is similar to that of a colorblind person. They can see hues of blue and green, but reds and pinks can be confusing. These might look greener, while purple might look like another shade of blue.
Cats also don’t see the richness and saturation of hues that we can see.
Distance
Experts believe that cats are nearsighted, which means they can’t see far. However, their ability to see close objects makes them well suited for hunting and catching prey.
Night vision
Cats cannot see fine detail or rich colors, but they have superior vision in the dark because their retinas have many dim light-sensitive rods. As a result, cats can see using about one-sixth the light that humans need.
Cats also have a structure behind the retina called the tapetum, which is thought to improve night vision. The cells in the tapetum act like a mirror, reflecting light passing through the rods and cones back to the photoreceptors, giving them another chance to pick up the small amount of light available at night. This is what makes cats’ eyes glow in the dark.
Nickolay Lamm, DVM of All Animal Eye Clinic, Kerry L. Ketring of DACVO, Dr. He consulted with DJ Haeussler and the Ophthalmology group at Penn Vet.
This article was originally published on October 16, 2013.
Read the original article on Business Insider
