Chicken vision is substantially different from ours. Understanding the hows and whys can help explain some unique chicken behaviors. Daniel Johnson explains their monocular vision, separated eye functions, third eyelid, perception of ultraviolet light and more.
. . . each eye sees different views and is designed for different uses . . the left eye excels at focusing on distant objects while the right eye is good at close focus . . . they can look at and observe two different things at once.”
Source: Hobby Farms, February 8, 2023. Link. Chickens don’t rely much on eye movements tending to move their heads in a rather quick, jerking fashion.