Editing Visible spectrum (section)

===Non-visual light detection===
In addition to the photopic and scotopic systems, humans have other systems for detecting light that do not contribute to the primary [[visual system]]. For example, [[melanopsin]] has an absorption range of 420–540&nbsp;nm and regulates [[circadian rhythm]] and other reflexive processes.<ref name="Enezi-2011">{{cite journal | vauthors = Enezi J, Revell V, Brown T, Wynne J, Schlangen L, Lucas R | title = A "melanopic" spectral efficiency function predicts the sensitivity of melanopsin photoreceptors to polychromatic lights | journal = Journal of Biological Rhythms | volume = 26 | issue = 4 | pages = 314–323 | date = August 2011 | pmid = 21775290 | doi = 10.1177/0748730411409719 | s2cid = 22369861 | doi-access = free }}</ref> Since the melanopsin system does not form images, it is not strictly considered [[Visual perception|vision]] and does not contribute to the visible range.