yeutterg Thanks for the answer and links.
Reading the second link, i stay with the impression that regulation and studys about led lightning and flickering
is really in the begining. Compared with the problems that are related here.
It seems that LED's displays are much more complex than led lightning, because there are other factors. LED backlight, Dithering, flickering due to inversion or other technics. All of them on the Flicker perceived unconsciously. Also PWM that can go from 120hz to several khz.
There can be flickering operating on slower frequencies, < 70hz, but at a pixel size, too small to be detected visually, but photoreceptors can detect it.
Also some of the problems usually associated with blue light can actually be related to flickering plus blue light. Since blue light is used for many things in the body, other that regulate the circadian mechanism. There are lots of photoreceptors sensitive to blue light and any of those can be affected by flicker at different frequencies or modulations.
Also color flickering might be relevant, like dithering, or other causes.
Just some lines of tought.