NOTE: Test on LCD / sample-and-hold. This effect doesn't occur on impulse-driven displays (CRTs, ULMB, LightBoost, impulsed OLED, or other strobe/flicker technologies)
This animation creates a persistence-of-vision effect by panning an image behind tiny slits, like walking along a picket fence and staring through, or scanning through through the crack of a door. This is an enhanced version of the Eye Tracking Demo. It clearly demonstrates the limitation of low refresh rate on any display, including CRT. This effect looks very pixellated on 60 Hz displays. This image becomes progressively sharper, the higher refresh rate you go. including 240 Hz LCD gaming monitors in non-strobed mode. This effect is noticeably clearer on 1ms TN displays than on IPS/VA LCD panels. Optical Illusion Invented by Mark D. Rejhon of Blur Busters.
Did you know? Blur Busters is the world's first site to test a genuine 480 Hz display. This animation demonstrates the limitations of even 120 Hz and 240 Hz displays. Using this test, it is easy to tell apart 120Hz, 240Hz and 480Hz. You need 480Hz+ to easily read the street name labels in the Panning Map Through Slits animation at 960 pixels per second. Laboratory displays (1000Hz+) have already confirmed it is still beneficial to keep increasing Hertz to quadruple digits.
This effect also applies to random holes instead of vertical lines, so this also applies to gaming in dense foilage such as jungles & forests, moving sideways behind lattice fences, and tilting head to scan behind door cracks. The faster the pixels modulate (120Hz, 240Hz, 480Hz), the more detailed persistence of vision becomes. Good full-readability (zero stroboscopic effect & no motion blur) with rapid occulsion effects, can require quadruple-digit display/VR refresh rates to match real-life in this test.
Spinning LED clocks, LED bike wheel effects, and old mechanical TVs (Nipikow wheels) use the same persistence-of-vision technique (very high Hz for individual flickering light sources). Higher Hz increases the resolution of persistence-of-vision effects.