Eyes (lenses/retina) are spherical with roughly (slightly more than) 100deg field of view each and a little more than 20deg left/right overlap at the nose. That

Eyes (lenses/retina) are spherical with roughly (slightly more than) 100deg field of view each and a little more than 20deg left/right overlap at the nose. That gives a total range of almost 180deg horizontal-yaw and 100deg vertical-pitch. You don't even notice most eye motion... if you did then every time you moved 2.5deg you'ld think about it. Apparent field of view is made up of many saccades that allow your much higher high resolution fovea to cover the interesting parts as it moves/scans/jumps around. By the time you're +/- 10deg from center, you've lost 5x in resolution. If you're like most people and the horizontal field is close to max, you'll do better stacking monitors than putting them side/side. Inter pupillary distance is a bit over 2in (~65mm), but that's usually small compared to screen distance, which is why I say roughly square (~16:14). https://en.wikipedia.org/wiki/Fovea_centralis https://en.wikipedia.org/wiki/Fovea_centralis