Description
Amber Light vs. White Light
White light from standard flashlights can span a wide range of wavelengths from 400 – 600 nanometers (nm). The blue-green component between 400 – 535 nm can wake you up and keep you awake even after your turn off the flashlight.
By restricting the wavelengths to above 550 nm, peaking at about 590 nm, you avoid this hazard.