Peripherally located CRTs: color perception limitations

Colors on a peripherally located CRT (cathode ray tube) may be misperceived. Subjects wrongly identified the color of a peripherally located, 1.3° circle displayed on a CRT 5% of the time if it was blue, 63% of the time if red, and 62% of the time if green. Blue could not be seen further than 83.1° off of the fovea (along the x-axis). Red had to be closer than 76.3° and green nearer than 74.3° before the subjects reported seeing the colors. These average color field dimensions changed with differing subject psychological states due to the observed visual field narrowing (i.e., reduction of the subject´s peripheral field of view) in both the relaxed and stressed states. A significant degree of visual field narrowing was noted for the relaxed states (8%), with a trend noted for the stressed state (2%). It is concluded that these color perception limitations must be kept in mind when designing CRT color formats for aircraft cockpits