Editing Visible spectrum (section)

===Different definitions===
Regardless of actual physical and biological variance, the definition of the limits is not standard and will change depending on the industry. For example, some industries may be concerned with practical limits, so would conservatively report 420–680&nbsp;nm,<ref>{{cite book |last=Laufer |first=Gabriel |chapter=Geometrical Optics |title=Introduction to Optics and Lasers in Engineering |chapter-url=https://books.google.com/books?id=4MxLPYMS5TUC&pg=PA11 |access-date=20 October 2013 |year= 1996 |isbn=978-0-521-45233-5 |page=11|publisher=Cambridge University Press |doi=10.1017/CBO9781139174190.004 |bibcode=1996iole.book.....L }}</ref><ref name="Bradt2004">{{cite book |last=Bradt |first=Hale |title=Astronomy Methods: A Physical Approach to Astronomical Observations |url=https://books.google.com/books?id=hp7vyaGvhLMC&pg=PA26 |access-date=20 October 2013 |year=2004 |publisher=Cambridge University Press |isbn=978-0-521-53551-9 |page=26}}</ref> while others may be concerned with [[psychometrics]] and achieving the broadest spectrum would liberally report 380–750, or even 380–800&nbsp;nm.<ref name="Ohannesian-2001">{{cite book |last1=Ohannesian |first1=Lena |last2=Streeter |first2=Anthony |title=Handbook of Pharmaceutical Analysis |url=https://books.google.com/books?id=DwPb4wgqseYC&pg=PA187 |access-date=20 October 2013 |year=2001 |publisher=CRC Press |isbn=978-0-8247-4194-5 |page=187}}</ref><ref name="Ahluwalia-2000">{{cite book |last1=Ahluwalia |first1=V.K. |last2=Goyal |first2=Madhuri |title=A Textbook of Organic Chemistry |url=https://books.google.com/books?id=tJNJnn0M75MC&pg=PA110 |access-date=20 October 2013 |year= 2000 |publisher=Narosa |isbn=978-81-7319-159-6 |page=110}}</ref> The luminous efficiency function in the [[Near-infrared|NIR]] does not have a hard cutoff, but rather an exponential decay, such that the function's value (or vision sensitivity) at 1,050&nbsp;nm is about 10<sup>9</sup> times weaker than at 700&nbsp;nm; much higher intensity is therefore required to perceive 1,050&nbsp;nm light than 700&nbsp;nm light.<ref name="Sliney-1976">{{cite journal |last1=Sliney |first1=David H. |last2=Wangemann |first2=Robert T. |last3=Franks |first3=James K. |last4=Wolbarsht |first4=Myron L. |year=1976 |title=Visual sensitivity of the eye to infrared laser radiation |journal=[[Journal of the Optical Society of America]] |volume=66 |issue=4 |pages=339–341 |bibcode=1976JOSA...66..339S |doi=10.1364/JOSA.66.000339 |pmid=1262982 |quote=The foveal sensitivity to several near-infrared laser wavelengths was measured. It was found that the eye could respond to radiation at wavelengths at least as far as 1,064 nm. A continuous 1,064 nm laser source appeared red, but a 1,060 nm pulsed laser source appeared green, which suggests the presence of second harmonic generation in the retina.}}</ref>