>I thought the harmful thing with leds were the refresh rate that you subconsciously notice the flicker. Thanks to the AC power system, even incandescent light bulbs flicker at 60 Hz (or 50 Hz for you chaps across the pond). All AC powered lights flicker by the very nature of AC current. Your TV screen, your phone screen, your computer monitors and your smartwatch screens all flicker too. If these flickering devices were causing harm, I think we'd have an awful lot of proof of it due to how long we've had AC powered lighting and TV (including CRT television) in our lives. Hell, even film projection flickers so even longer than any of these "modern" devices on that one.