Editing Visible spectrum (section)

=== Vision outside the visible spectrum ===
Under ideal laboratory conditions, subjects may perceive infrared light up to at least 1,064&nbsp;nm.<ref name="Sliney-1976" /> While 1,050&nbsp;nm NIR light can evoke red, suggesting direct absorption by the L-opsin, there are also reports that pulsed NIR lasers can evoke green, which suggests [[two-photon absorption]] may be enabling extended NIR sensitivity.<ref name="Sliney-1976" />

Similarly, young subjects may perceive ultraviolet wavelengths down to about 310–313&nbsp;nm,<ref name="Lynch-2001">{{cite book |last1=Lynch |first1=David K. |url=https://books.google.com/books?id=4Abp5FdhskAC&pg=PA231 |title=Color and Light in Nature |last2=Livingston |first2=William Charles |publisher=Cambridge University Press |year=2001 |isbn=978-0-521-77504-5 |edition=2nd |location=Cambridge |page=231 |quote=Limits of the eye's overall range of sensitivity extends from about 310 to 1,050 nanometers |access-date=12 October 2013 |archive-url=https://web.archive.org/web/20221008031821/https://books.google.com/books?id=4Abp5FdhskAC&pg=PA231 |archive-date=8 October 2022 |url-status=live}}</ref><ref name="Dash-2009">{{cite book |last1=Dash |first1=Madhab Chandra |url=https://books.google.com/books?id=7mW4-us4Yg8C&pg=PA213 |title=Fundamentals of Ecology 3E |last2=Dash |first2=Satya Prakash |publisher=Tata McGraw-Hill Education |year=2009 |isbn=978-1-259-08109-5 |page=213 |quote=Normally the human eye responds to light rays from 390 to 760 nm. This can be extended to a range of 310 to 1,050 nm under artificial conditions. |access-date=18 October 2013 |archive-url=https://web.archive.org/web/20221008031820/https://books.google.com/books?id=7mW4-us4Yg8C&pg=PA213 |archive-date=8 October 2022 |url-status=live}}</ref><ref name="Saidman-1933">{{cite journal |last1=Saidman |first1=Jean |date=15 May 1933 |title=Sur la visibilité de l'ultraviolet jusqu'à la longueur d'onde 3130 |trans-title=The visibility of the ultraviolet to the wave length of 3130 |url=http://visualiseur.bnf.fr/ark:/12148/bpt6k3148d |url-status=live |journal=[[Comptes rendus de l'Académie des sciences]] |language=fr |volume=196 |pages=1537–9 |archive-url=https://web.archive.org/web/20131024092515/http://visualiseur.bnf.fr/ark:/12148/bpt6k3148d |archive-date=24 October 2013 |access-date=21 October 2013}}</ref> but detection of light below 380&nbsp;nm may be due to [[fluorescence]] of the ocular media, rather than direct absorption of UV light by the opsins. As UVA light is absorbed by the ocular media (lens and cornea), it may fluoresce and be released at a lower energy (longer wavelength) that can then be absorbed by the opsins. For example, when the lens absorbs 350&nbsp;nm light, the fluorescence emission spectrum is centered on 440&nbsp;nm.<ref>{{cite book |last1=Kurzel |first1=Richard B. |last2=Wolbarsht |first2=Myron L. |last3=Yamanashi |first3=Bill S. |chapter=Ultraviolet Radiation Effects on the Human Eye |date=1977 |title=Photochemical and Photobiological Reviews |pages=133–167 |doi=10.1007/978-1-4684-2577-2_3|isbn=978-1-4684-2579-6 }}</ref>