What is the Phi Phenomenon?
The phi phenomenon (sometimes called the phi effect or phi movement) is a psychological term for the illusion of motion upon seeing two nearby lights fired in rapid succession. More importantly, the phi phenomenon is related to the ability of viewers to perceive motion from a series of still images projected onto a screen at 24 frames per second (or any speed if fast enough). It was chosen as the name of this web site to reflect the webmaster’s off-line training as a psychologist and because he fell in love with the alliteration in the Phi Phenomenon Philosophy.