Measuring White Light ```Name: Unknown Status: other Age: 20s Location: N/A Country: N/A Date: 1999 ``` Question: can white light be measured in wavelengths? Or is this the wrong type of question for this site? Replies: White light is a mixture of light of wavelengths between 400 and 800 nm. So it can certainly be reported as the distribution of the number of photons at each wavelength (this will usually be a smooth curve). But no single wavelength will characterize or specify white light. Richard E. Barrans Jr., Ph.D Assistant Director PG Research Foundation, Darien, Illinois White light contains many different wavelengths, all around .5 micron. Tim Mooney "White" light is a mixture of all colors of light. As such it does not have a wavelength. You can separate the white light into its component colors and each color would have a wavelength associated with it. Asking for the wavelength of white light is like asking for the height of a forest. The forest has trees of many different heights. To assign a single number to the height requires selecting a single tree and measuring it. But that doesn't really tell you much about the forest overall. Dr. Bradburn white light can be separated by a prism into a whole rainbow of different wavelengths. So its really a mixture of lots single colors. So white light could be said to have a RANGE of wavelengths, say from 0.4 microns to 0.7 microns. And of course in the end, these are just the wavelengths of light that a human eye is sensitive to. Dr. Ross Click here to return to the Physics Archives

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