the standard that for a uniformly aroused retinal region peripheral to the fovea, the threshold for luminance is inversely proportional to the square root of the region aroused.

PIPER'S LAW: "Ricco's Law and Piper's Law are often interchanged when they should not be, as they are different."
Cite this page: N., Pam M.S., "PIPER'S LAW," in PsychologyDictionary.org, April 7, 2013, https://psychologydictionary.org/pipers-law/ (accessed September 20, 2021).