600 ppi this year or next? Good ereader speculates

[fjtorres]

Originally Posted by Barty

OLED has delivered on the hype.

OLED was supposed to be so cheap it could be used on disposable displays.
It was supposed to be manufacturable via inkjet style deposition in sizes up to wall widths.
Instead it has turned out to be a premium tech with marginal improvement on brightness vs ever improving LCD and not particularly suitable for large displays.

MicroLED faces the same scaling issues which is why I expect it's niche will be small displays where pixel density is critical: watches, phones, and small tablets. If power consumption proves to be as low as projected it will hit eink levels but with color and animation.

[HLS]

Originally Posted by AnotherCat

I don't really know why either but I would think it is likely mainly because of the poor contrast of eink displays, that due to both the current display technology and their being reflective. Increasing the "pixel" density will help blacken the blacks and that will in turn make the fonts denser and appear "crisper" against the background.

EDIT: On a reread maybe you mean the Aura was crisper? If so I could only imagine it would be a better font or a better contrast display compared to the others. But, in the general case, my original comments stands in that I would expect for eink higher ppi would likely enable darker fonts.

My lower ppi Aura from Walmart has a better display than my higher ppi ereaders. I think it may be the lighting of the device perhaps.

[Shad Plante]

Originally Posted by kcladyz

My lower ppi Aura from Walmart has a better display than my higher ppi ereaders. I think it may be the lighting of the device perhaps.

It could be either be the quality of the lighting or the contrast in the screen itself. I would take a very high contrast 212 ppi screen over a 300 ppi screen with the typical contrast you see now. Easier to read and better battery life.

[k1sh]

Originally Posted by sydmalicious

Will We See 500 or 600 PPI e-Paper Displays in 2019 or 2020?

I don’t know if it is necessary but the commenters suggested that it is contrast that needs to improve not the resolution. A guy in the comments argued you can’t really discern the difference in resolution from 300 ppi to 600 ppi as the human eye isn’t capable of seeing those details. Perhaps, but I have the iPhone XS Max and latest iPad Pro and it seems much of those displays are noticeably crisper than my 1st gen iPad Pro and iPhone 8 Plus.

What do you think?


Sent from my iPad using Tapatalk

Above 300-350 DPI and at reading distance, the average person can barely tell the difference. You may notice that the image gets sharper as the DPI goes up (especially if you have very high visual acuity), but for the purpose of reading or even images, it's unlikely that a density higher than the above can give you any more useful "information."

In simple words, you may tell the difference in sharpness, but it wouldn't really matter in reading. Bear in mind that the density of most print materials (like story books and newspaper) is below 300 DPI, but you can read them without any issues, can't you?

What I'm waiting to see is large (9" and above) e-readers with 300 DPI. I read professional PDF from scientific journals and books for my work, and most of them are in 2-columns and small font, so it would be nice to be able to have the entire page on the screen and be able to read it.

Originally Posted by k1sh

What I'm waiting to see is large (9" and above) e-readers with 300 DPI. I read professional PDF from scientific journals and books for my work, and most of them are in 2-columns and small font, so it would be nice to be able to have the entire page on the screen and be able to read it.

My brother-in-law is a professor of engineering and has mentioned the same issue. I'm curious what is the minimum size screen that you find necessary to read those comfortably? For me it'd be more like 12 inches, from the few that I've seen.

[haertig]

Higher resolutions are a marketing technique more than anything. There comes a point where higher resolutions are totally wasted, because the human eye cannot resolve them. Of course, there are many humans who claim they can (???).

A parallel example is TV sets. We have a 4K 70" set. I would have been perfectly happy buying a 720 one, because our couch is 12.5 feet from the screen. At that distance (for a 70" screen) the human eye is just starting to be able to barely resolve the difference between 720 and 1080. Totally forget about 4K. But finding even a 1080 large screen set is getting tougher these days since marketing is all about 4K. Yeah, I can tell a major difference with 4K if I feed the TV with a high resolution video source, AND position myself about one foot from the screen. But that's not the way I normally watch TV. The couch is much more comfortable.

Another example: Several years ago my wife bought a high end professional Nikon. I believe the sensor has only 8 (10?) megapixels. But that camera absolutely blows away the consumer and budget grade offerings that come in 12, 16 and probably even 20 megapixels these days. It totally annihilates them - the differences in picture quality are truly laughable.

After a point, higher resolutions are meaningless, unless you are marketing your devices to hawks, eagles and other raptors. Is that point 300dpi (or even less?) for eReaders - I don't know. I have not tried to research resolution, screen size, normal reading distance, and human eye limitations yet. But my gut tells me we are moving away from a practical/functional discussion into a marketing discussion.

[GeoffR]

Originally Posted by haertig

Higher resolutions are a marketing technique more than anything. There comes a point where higher resolutions are totally wasted, because the human eye cannot resolve them. Of course, there are many humans who claim they can (???).

The human eye can see things that are much smaller than what it can resolve. You don't need to be able to resolve the individual dots on a screen to be able to see the difference that a higher DPI screen makes.

The "resolution" of the human eye is often given as one minute of arc, which corresponds to about 344 DPI at a distance of ten inches.

However anyone with normal eyesight can easily see Mars, which has an apparant size of 25 seconds of arc at its closest approach, equivalent to one dot on a 825 DPI display at ten inches.

[j.p.s]

Originally Posted by GeoffR

The human eye can see things that are much smaller than what it can resolve. You don't need to be able to resolve the individual dots on a screen to be able to see the difference that a higher DPI screen makes.

Correct. Being able to resolve individual pixels is a sure sign that the resolution is too low or the display too close.

Originally Posted by GeoffR

The "resolution" of the human eye is often given as one minute of arc, which corresponds to about 344 DPI at a distance of ten inches.

However anyone with normal eyesight can easily see Mars, which has an apparant size of 25 seconds of arc at its closest approach, equivalent to one dot on a 825 DPI display at ten inches.

It is a bit more complicated than that. All but the closest stars can not be resolved even by a powerful telescope, But individual stars thousands of light years away are easily seen with the unaided eye because they are so bright.

But even high brightness is not required for this effect. High altitude digital photography can show roads significantly narrower than a single pixel because they affect the color and brightness of the pixels they are in.

You can do the same thing taking pictures of narrow black lines on white paper, but with today's camera resolutions, it might not be trivial to get far enough away from the paper.

[Barty]

Originally Posted by sydmalicious

I have the iPhone XS Max and latest iPad Pro and it seems much of those displays are noticeably crisper than my 1st gen iPad Pro and iPhone 8 Plus.

The xs max has an OLED screen, which has much better contrast. You just proved their point.

[haertig]

Originally Posted by GeoffR

The human eye can see things that are much smaller than what it can resolve.

The human eye can detect photons hitting the retina, given a high enough quantity of photons. The source of the photon(s) can be infinitesimally small, as in a star many light-years away. This is not "seeing a photon" however. In order to be able to distinguish something from a different something sitting right next to it, you have to be able to resolve the somethings. Otherwise you are merely observing one somethings effect on the other somethings in its vicinity. Cramming more and smaller somethings into the vicinity will not change what your eye can discern.

None-the-less, it appears there is indeed a market of people who will buy 600dpi eReaders. And then 1200dpi after that. And on and on.

[j.p.s]

Originally Posted by haertig

The human eye can detect photons hitting the retina, given a high enough quantity of photons. The source of the photon(s) can be infinitesimally small, as in a star many light-years away. This is not "seeing a photon" however. In order to be able to distinguish something from a different something sitting right next to it, you have to be able to resolve the somethings. Otherwise you are merely observing one somethings effect on the other somethings in its vicinity. Cramming more and smaller somethings into the vicinity will not change what your eye can discern.

None-the-less, it appears there is indeed a market of people who will buy 600dpi eReaders. And then 1200dpi after that. And on and on.

This morning, you were going on about 720p being plenty for large TVs. But hook a computer to 1080p TV and bring up a text document in whatever app you like. There is no way a typical 8.5" x 11" PDF page is going to be comfortable to read. Just imagine how much worse 702p would be.

A bit mapped font optimized for screen readability might look OK at 60ish lines of text per screen on 1080p, but those fonts are long gone from general use and toolbars and such take up a lot of vertical space. Text can be more demanding than images because a low res image might look OK until you see it next to a high res image. But rough looking text looks bad without needing anything for comparison.

Also, e-ink displays can benefit from another aspect of high resolution. E-ink can only show 16 shades of gray. High res displays have effectively more shades via dithering without looking noisy as a result.

[rvcjew]

Originally Posted by haertig

The human eye can detect photons hitting the retina, given a high enough quantity of photons. The source of the photon(s) can be infinitesimally small, as in a star many light-years away. This is not "seeing a photon" however. In order to be able to distinguish something from a different something sitting right next to it, you have to be able to resolve the somethings. Otherwise you are merely observing one somethings effect on the other somethings in its vicinity. Cramming more and smaller somethings into the vicinity will not change what your eye can discern.

None-the-less, it appears there is indeed a market of people who will buy 600dpi eReaders. And then 1200dpi after that. And on and on.

It also depends on the size of the device for sure. A 450DPI on the 8 inch devices would be be much better as being so near sighted I can see the pixels easily on these devices, but if they just raised the resolution that would just be better but then it would take more battery ect. The more pixels the smaller they become.
Malcolm

[DuckieTigger]

Originally Posted by haertig

The human eye can detect photons hitting the retina, given a high enough quantity of photons. The source of the photon(s) can be infinitesimally small, [...]

That, of course, is oversimplifying it a little bit too much. You almost make it sound as if the eye (or rather the retina) is just a dumb sensor. The retina is technically part of the brain unlike all the other senses which are merely sending signals to be interpreted by the brain. The visual cortex still plays an important role in interpreting, especially coordinating and mixing the signals from both eyes, but a lot of image processing, pattern recognition, and data compression already happens in the retina before it ever hits the visual cortex. The optic nerve simply does not have enough bandwidth. Comparing the retina with a sensor in a camera is not doing the retina any justice.

Or in short: increasing the resolution higher than the "native resolution" of the retina can make the image look better even past the point of being able to resolve individual pixels.

[haertig]

Originally Posted by j.p.s

This morning, you were going on about 720p being plenty for large TVs.

Actually, I was going on about 720p being right at the edge of human eye resolution for a 70" screen, when viewed from 12.5' away.

To set the record straight, I should have said 65". That was my mistake. We used to have a 70" 1080p TV, but replaced that with a 65" 4K TV. Not because we wanted the higher resolution, since that is totally wasted at our viewing distance. But there are more choices for TV's today (feature-wise) in the 4K arena.

Do you have a screen larger than 65"? Do you sit closer than 12.5'? If so, then the human eye can indeed resolve more than 720p. You have to look at screen resolution, ... and screen size, ... and viewing distance. I was stating the resolution limits of the human eye for my specific viewing setup.

[j.p.s]

Originally Posted by haertig

Actually, I was going on about 720p being right at the edge of human eye resolution for a 70" screen, when viewed from 12.5' away.

To set the record straight, I should have said 65". That was my mistake. We used to have a 70" 1080p TV, but replaced that with a 65" 4K TV. Not because we wanted the higher resolution, since that is totally wasted at our viewing distance. But there are more choices for TV's today (feature-wise) in the 4K arena.

Do you have a screen larger than 65"? Do you sit closer than 12.5'? If so, then the human eye can indeed resolve more than 720p. You have to look at screen resolution, ... and screen size, ... and viewing distance. I was stating the resolution limits of the human eye for my specific viewing setup.

55", eyes about 4' from screen.

The point GeoffR and I were making is that picture quality is barely no longer seriously degraded when pixels have just become unresolvable. PQ continues to improve as pixel size decreases. For example, a 1 pixel wide black line on a white background will be black if it is registered with a line of pixels, but it will be mid-gray and double width if its midpoint is between two lines of pixels. But on a display with twice the resolution of your "limit of usefulness", the line will be black and the proper width.