1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

B White light vs visible spectrum

  1. Jun 17, 2017 #1
    Does white light contain only the wavelengths of visible spectrum (i.e only from 400nm to 800nm)?
  2. jcsd
  3. Jun 17, 2017 #2
    It seems that, to receive the name of white light, it may or may not contain contributions of the non visible range of the spectrum. So white light may be considered a class containing several different states of the EM field.
  4. Jun 17, 2017 #3
    There are many definitions of "white light", none are truly quantitative. For example:
    "Apparently colourless light, for example ordinary daylight. It contains all the wavelengths of the visible spectrum at equal intensity."
    "light perceived by the eye as having the same color as sunlight at noon."
    "the complete mixture of all of the wavelengths of the visible spectrum."

    Some are contradictory, e.g. sunlight at noon does not have equal intensities of all wavelengths in the visible spectrum. But none that I found excluded radiation of nonvisible wavelengths. Herschel discovered IR by noting that there was energy in "white sunlight" beyond visible red.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted