Brief History of The Pulfrich Effect

In 1922, Carl Pulfrich wrote a paper of the now called Pulfrich effect. In his paper, he gave credit to others for their contribution towards the Pulfrich effect. Pulfrich stated the phenomenon was brought to his attention pior to writing his paper by Professor Max Wolfe. Professor Wolf describe " a noteworthy steroeffect which now and then disturbingly confronted him during rapid movement of a pair of plates in the sterocomparator." (Christianson & Hofstetter, 1972)

Pulfrich also gave full credit to a techical assistant, F. Fertsh, for the findings that the "difference in brightness of the view in front of the two eyes elicited the (Pulfrich) effect." (Christianson & Hofsetter, 1972) Fertsh was also credited for his explanation of the phenomenon in terms of perceptual latency.

Pulfrich's son, Hans, a doctor of Philosophy, was also given due credit for coming up with the theoretical analysis of the "path of apparent movement based on an assumed perceptual latency" ( Christianson & Hofstetter, 1972). Pulfrich only credited himself for the notion of the pulfrich phenomenon could be used in heterochromatic photometry.

In 1922, Pulfrich demonstration apparatus did not include a pendulum as it is usually stated in description of the pulfrich effects. Instead, blocks of square apectures were used. Below are the designs of Pulfrich's earlier models.( Figure 1 and 2)

(Christianson & Hoffsetter,1973)