This sensation may be caused by the flickering as the phosphor fades towards black before the screen is retraced. There are CRT monitors with long persistence p

This sensation may be caused by the flickering as the phosphor fades towards black before the screen is retraced. There are CRT monitors with long persistence phosphor that mitigate this, but it makes them unsuitable for motion video. My favorite concept is that of the Tektronix vector terminals. They trace the image to a long persistence phosphor as necessary and then retain the image without retracing it by constantly bombarding the whole screen with just enough electrons for the already lit phosphor to stay lit. As a result, once the image is drawn the screen may have a little brighter black than a "normal" CRT monitor, but no flickering. I've never seen one in real life, but it seems like it would be great for ergonomics.