The race for brightness considered harmful :)
The problem that LCDs have and CRTs didn't is that you lose color reproduction/contrast if you turn down the brightness to healthy levels.
Hopefull OLED fixes that and becomes affordable. But I'm afraid manufacturers will still race for brightness even on a technology that doesn't need it.
> E-ink has the advantage that it automatically shows the correct brightness for the lighting conditions
Tbh I find eink very readable in bright sunlight and it's all downhill from there, to the point that i prefer reading on a tablet with brightness way down and the lights off to eink with a lamp on. But that may be a consequence of staring into LCDs most of my life.
For me, the screens I use are always at the brightness where white regions are as comfortable as a piece of paper. Sure, colors aren't reproduced "as the artist/developer wanted" at those values, but neither do I need that, nor do we have e-ink screens that can reproduce color more accurately.
I just want to create software, research stuff on the internet, arrange my music etc. and if I feel like doing that for 10 hours straight, I only want the screen to tire my eyes as little as possible.
I also read a lot of books and research material, both on Kindle and paper. My eyes get tired after hours of doing that as well. Light is not the only factor.
So although it's good to try to be optimal about the light that gets in your eyes over large periods of time, it's best to also try periodic rest and moving some activities to non-screen mediums instead of fretting endlessly over the last 5% of screen light optimization.
It doesn't because e-ink is a non-light-emitting technology so has no concept of brightness. Ambient light is what lights it up usually (unless one turns an entirely optional backlight on to read in the dark). So you don't need to adjusts as there's nothing to adjust, it's literally ambient light bouncing back, so is the same brightness by virtue of being the same light source.
Conversely, typical displays (TN, IPS, OLED, CRT even...) being a light emitting technology, one needs to turn backlight up as ambient light increases as both compete. (That is, unless it's a transflective LCD, but even then it's quite dim in ambient light).
> there's nothing inherently less tiring about it
e-ink really is more like paper, while typical displays are like turning a flashlight straight towards your eyes.
e-ink doesn't flicker.
I know that past a certain number of Hz our brain just mushes the images together and we magically perceive that the motions on the screen are fluid, just like we believe our electric lights are completely on all of the time. But even though our final perception might be continuous, maybe there are steps in the image processing pipeline in our brain where something gets overloaded by the discrete refreshing of the screen.
Refresh rate is the rate at which new information is displayed. Flicker is things turning on and off.
As the parent mentioned, some screens use fast cycles of turning on/off to modulate perceived brightness, but this is not always the case.
All LCDs "flicker" in the same way all movies "flicker". The technology simply displays or flashes a series of still images quick enough to be perceived as fluid motion or video.
(And in fact, some of the e-ink readers with optional display lighting will use PWM to modulate its brightness, and then exhibit flicker. This is a super dumb engineering choice, though, so it's not very common. The Kobo Forma was an offender.)
As an aside, I'd love a secondary e-ink monitor. Hopefully the technology improves so prices come down.
No, e-ink displays and controllers support partial updates.
of course it has a refresh rate when there is a change in the image, but if I'm reading something completely static then literally nothing changes whereas an LCD screen still does things in the background
When the image is not static, because an LCD updates line by line, if you don't coordinate your data updates to the refresh rate you can get artifacts such as "tearing", where different sections of the monitor show different data that doesn't fit together. However, e-ink displays doing differential or fast partial updates have similar problems (and some exciting new ones, making refresh overall quite bad). You just usually don't try to display fast moving imagery on them.
e-ink displays are what is known as "bi-stable", meaning you don't need to apply a voltage to keep a pixel in a particular state, only when you want to change that state. This is not true for LCD, where you do need to keep supplying a voltage. This however doesn't result in any visual change if the voltage isn't changing.
The real difference here is that LCDs aren't reflective, unlike e-ink. So you need a backlight, and that light shining at your eyes is more tiring than how things work with an e-ink display. That either doesn't need a backlight (in a bright ambiance), or the LED lighting isn't behind the display and doesn't shine directly at you, but rather bounces through the display surface. This is a nice quality.
actually they kinda are
Blue light from close distance screens is the enemy of your eyes and has many other side effects.
https://health.ucdavis.edu/blog/cultivating-health/blue-ligh...
https://en.wikipedia.org/wiki/Redshift_(software)
E-ink reflects light over a broad spectrum, so the amount of blue depends on the amount of blue it's illuminated with. It can be higher than the LCD in some conditions.
Besides, in the last 2 years people reported many more cases of eye strain and blurred vision (at least in my country), because "home" is not really the best work environment for 95% of the people.
There's a reason why offices are always well illuminated.
e-inks are usually used with lights turned off and when ate not I use the red light because it's better for reading.
LCD typically has higher maximum contrast than e-ink.
What you're describing happens when lowering the brightness through software (either Gamma adjustments or a dark overlay) because in that case you're only changing the software pixels to be darker.
Although even in that case, newer miniLED/quantumDot LCD screens also lower the LED brightness when pixels get darker, because they have more granular control and dimming an LED doesn't cause shadows over a large area of the screen anymore.