I want to see an LCD with really good light sensors and a low brightness setting and see how it looks any different in uniform light.
Put a different way: when light falls on an eInk "pixel" it gets absorbed and then re-emitted, modulo intensity. That's how we see the vast majority of surfaces in the world: they absorb light and then re-emit it, possibly changing its intensity and color (frequency). Technologies like OLED directly emit light; not reacting significantly to the ambient light that falls on them. But if one we able to measure the light falling on each individual pixel of an OLED, one could adjust each pixel to mimic the behavior of a physical object. It could "simulate" eInk, so to speak. If the mimicry is close enough, then there's no fundamental difference between the two. They'd both be emitting the same frequency and intensity of light.
In fact I recall a post, mostly likely here on HN: Someone took a high quality Apple display and rigged it with an array of ambient light sensors, put it in a decorative art frame and hung it on the wall. With some software and calibration they were able to get it to look convincingly like a real piece of art, fooling many of their guests.
eInk has been around for decades now and has remained an obscure niche. It's possible we'll see a renaissance for it, with the patents hopefully expiring? But there's no reason we shouldn't also be pursuing better ambient light calibration for our existing displays.
P.S. It's not accurate to say that eInk is a "reflective" display, as it does not primarily reflect light. Otherwise it would look like a mirror. But saying "emissive" versus "reflective" is common parlance for differentiating technologies like eInk from technologies like LCDs and OLEDs. Nitpicking the terminology is not particularly helpful though.
Too bad nobody actually makes one. There's no way to buy a hypothetical, so e-ink it is.
The relevant question is whether you can buy an LCD that calibrates well enough, and the answer is not "obviously no".
There is one specific difference between the light from LED screens vs e-ink : polarization. LED displays work by adjusting the polarity of the backlighting and then passing it through a polarizing filter. An e-ink display image is unpolarized light. It's not clear whether the polarity of LED has the potential to cause eye strain or other negative effects, but it is certainly a quantifiable difference.
Are e-readers really obscure? Seems like a pretty big market.
I also saw something but couldn't find it again :)
Is "reflective" always orderly? I mean, can there be a 100% matte reflection?
I also use an e-ink reader sometimes because it looks so much better under direct sunlight, and because it's a single purpose physical device. But I'd love to see some more substantial work backing the eye and neurological disorders claims, from actual researchers in the field, with n greater than 1. Otherwise, that's how you get a snake oil market for geeks.
Frankly, I could use either tech for similar reasons.
E-ink would be superior for overall viewing and eye strain, however both have merit. The LCD would likely be faster, with a much narrower sweet spot for viewing.
And I wonder about these Vanta Black type pigmemts too. E-ink I have seen is really good, but could potentially be crazy good. Maybe that cannot be used, or is too expensive. But yeah, I wonder.
But to be more precise: both "emit" light depending on the ambient light. Of course it's comparable.
The only thing really throwing off the LCD would be the white balance, but with the right sensor that too could be fixed (e.g. a camera with fixed wight balance behind milk-glass).
(E-)Paper reflects blue light, LCD backlight emits it. The only difference is that the color balance and brightness don't change with the sunset on your screen unless you install a tool like flux.
Light is light. Looks the same = probably is the same. Bands are just a bit narrower with LEDs, but I wonder if that makes any difference biologically if it looks the same.
eink/epaper is reflecting ambient light just like every other object in the environment so your vision won't need to adjust when glancing back and forth
If you set your monitor to the same brightness that paper or a non-backlit screen would have in your room, then your vision doesn't have to adjust to the different brightness levels.
Same for TV. Don't watch TV in a dark room!
When I had a modest home theater with a projection TV (the old bulky kind, not a separate projector and screen), one of the best things I did was to light the white wall behind it with a soft neutral gray light.
The technique at the time was to use a small fluorescent desk lamp on a small table behind the TV, with the fluorescent tube wrapped in a specific color of lighting "gel" to make it a neutral gray. The lamp was aimed up at the wall behind the TV. This made everything much easier on the eyes.
The main trouble I think is that very few (any?) manufacturers are making front-lit LCD panels at typical monitor sizes and resolutions. I guess there's not really a market for it? But if such a thing exists I'd compare the heck out of it and eInk.
Viewing angle would be another pain point with them, but that also came a long way and you could chose one with good angles if needed.
This is relevant for pretty much any knowledge worker job as well.
All LCD's essentially use a similar liquid crystal pixel that serves as a variable light shutter for polarized light. It's the back- and front-planes (e.g. addition or omission of RGB color filters, different types of backlights, fully or partially reflective layers, etc.) that differentiate different types of LCDs. If you have an old LCD laying around, with many of them you can actually take the different layers apart to access the active or passive matrix LCD panel (you'll end up with a transparent LCD). I did it once with a tiny LCD, it's pretty cool. Then you can play around with adding your own layers/lighting effects.
1.) https://en.m.wikipedia.org/wiki/Transflective_liquid-crystal...
2.) https://www.winstar.com.tw/products/tft-lcd/transflective-tf...