Blue Light Affects Sleep (and here's why)
We know that night-time exposure to blue light keeps people up late. We believe that f.lux adjusts colors in a way that greatly reduces the stimulating effects of blue light at night.
To understand the effects of f.lux on sleep, we've spoken with some researchers, and we've read a whole lot of papers.
The science that explains why blue light keeps you up was begun many years ago in the study of bird migration, and it continued in humans with the discovery of a new photoreceptor in the eye, called
Melanopsin. Many are familiar with the "rods and cones" that provide our visual capabilities, but it was only about 15 years ago that retinal ganglion cells containing melanopsin, which are sensitive to a narrow band of blue light in the 460-480nm range, were discovered, and their unique effect on sleep was investigated.
The experimental research suggests that
an average person reading on a tablet for a couple hours before bed may find that their sleep is delayed by about an hour. Clearly, the details are complicated, but that's why we get to cite so many very interesting papers.