Narrator: It's 1:00 a.m. You should be sleeping but you're glued to your smartphone, catching up on the latest news, Facebook updates and tweets. It turns out that the smartphones and tablets that keep you connected and organized may also be keeping you awake.
See, our eyes perceive light in a range of wavelengths. Different wavelengths produce different color sensations and those sensations help tune your internal clock. Here's sleep researcher Brian Zoltowski.
Go back to the ancient art of reading a "real" book before bed.