With all the arguing over light sources one crucial fact has escaped mention. Common to all sources is that light intensity obeys the inverse-square law. Intensity 10 feet from a source is consequently a hundredth that at one foot away. At 30 feet away, intensity is reduced by a factor of 900.
Based on this relationship, a person is likely exposed to a lot more blue light from computer or television use, even from LED headlights of oncoming motorists, than from an LED lamppost.
Len Mansky
Roslyn
