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by nybble41 1520 days ago
> because you aren't staring into a bright light source that refreshes 60 times a second

LCDs update 60 times per second (or more… 120 Hz displays are becoming more common) but they don't flicker the way CRTs used to, so there's no reason to think this would contribute to eye strain. Brightness could be an issue but you can just lower the brightness of the screen to match the surroundings.

As I see it the advantages of e-ink displays lie mainly in their visibility in direct sunlight and minimal idle power consumption.

1 comments

This isn't entirely true. It's not the same intensity of flicker, but LCDs do have a small amount of flicker at about half their refresh rate to flip voltage and reduce the chance of burn-in. Also, the backlight itself may flicker depending on what kind of light source is used (especially if it's not an LED backlight, but cheap LED lights do flicker -- see christmas lights -- so it's possible some cheaper LED panels might have this effect too?).
Cheap LED christmas lights flicker because they don't have a bridge rectifier, so half of the input waveform is zero, at 60Hz. You're not going to see that kind of flicker in anything that requires real DC power (PWM frequencies for brightness control are generally way higher than 60Hz).

Some displays do this as a feature though (known as backlight strobing, motion blur reduction, etc.): LCDs take time to transition, so if you keep the backlight on at all times, you'll potentially see blurring from persistence of vision while the display is mid-transition. Instead, you can turn the backlight off until the screen has transitioned and then turn it back on so that you never show a partially transitioned image.