What's the mechanism of action behind the reduced eye strain, and why is e-ink needed to achieve it? Lack of flicker? True of any non-PWMed monitor. Reduced b

What's the mechanism of action behind the reduced eye strain, and why is e-ink needed to achieve it? Lack of flicker? True of any non-PWMed monitor. Reduced brightness or contrast? Conventional displays can be turned down to match e-ink. Lack of subpixels? High DPI displays make subpixels invisible under normal circumstances. Smoother spectrum white? I doubt this makes a difference, but it's not completely implausible, because the eye does have some chromatic aberration. But greyscale LCDs are available. Lack of polarization? Polarization is visible (see https://en.wikipedia.org/wiki/Haidinger's_brush https://en.wikipedia.org/wiki/Haidinger's_brush ), but it's a very minor effect. It seems unlikely that something so difficult to see could cause eye strain. OLED displays don't show this effect.