Some people say that dogs can't see at night. Is it true?/You don't say.

The dog's eye adjustment ability is only 1/5~ 1/3 of human's, and it can't be seen clearly beyond this distance, but the moving target can see the distance of 825m, with a wide field of vision, and the left and right field of vision of one eye ranges from 100 to 125.

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The dog can only see 25 degrees with one eye, so it can't see the nearest distance ahead. The lens of a dog's eyeball is relatively large and deformed like a horse's eyeball, so it is impossible to adjust the sense of distance. Twenty or thirty meters is probably its limit. Dogs have a special ability to detect moving objects; They can detect images that move 70 lines per second, while ordinary TV images move about 60 lines per second.

Dogs have better eyesight than people in dim light. Dogs are natural carnivores and live by hunting, so they also have considerable vision in the dark. Dogs' eyes can see short-wavelength colors. In addition, the dog's cornea is bigger, which allows more light to enter the eyes, so it is easier to see things in dim light.

The difference between human vision and dog vision lies in the reaction to light. The human eye reacts to the three primary colors (red, green and blue) that cause various colors. Dr DennisBrooks, associate professor of ophthalmology at the College of Veterinary Medicine, University of Florida, said that dog vision is different from human vision. Dogs can't distinguish colors like people.

Dogs can distinguish different shades of blue, indigo and purple, but they are not particularly sensitive to high chroma colors such as red and green in the spectrum. Dr. Brooks' research shows that red is dark for dogs and green is white for dogs, so the green lawn is white for dogs.

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