Now that I’ve gotten my Oculus Rift DK2 (mostly) working with Vrui under Linux, I’ve encountered the dreaded artifact often referred to as “black smear.” While pixels on OLED screens have very fast switching times — orders of magnitude faster than LCD pixels — they still can’t switch from on to off and back instantaneously. This leads to a problem that’s hardly visible when viewing a normal screen, but very visible in a head-mounted display due to a phenomenon called “vestibulo-ocular reflex.”
Basically, our eyes have built-in image stabilizers: if we move our head, this motion is detected by the vestibular apparatus in the inner ear (our “sense of equilibrium”), and our eyes automatically move the opposite way to keep our gaze fixed on a fixed point in space (interestingly, this even happens with the eyes closed, or in total darkness).
Figure 1: Black smear. It’s kinda like that.
