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Comment by sparker72678 | Hacker News Reader

Yes, modern e-ink capsules are not precise. In fact, they're not intended to be.

If you look at an e-ink display under a microscope you'll see that the "pixels" are more like "shards" of variously-shaped cells.

https://twitter.com/sqfmi/status/1178018736684580865

The "pixels" are made of the actual addressing grid that creates the currents that attract the pigment in the capsules.

This is part of what ends up giving the appearance of a higher-resolution display when rendering text, as you get some softer edges "for free." (And it's what makes the display look 'blurry' for some viewers.)

So, to your question, there's currently no attempt with the technology to precisely place the colors on the display. The capsules are just spread all over, and the grid does the work.

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This makes me sad. Based on what you're describing it's sounding like my dream of having eReaders that are anywhere near sharp enough to do visually rich, full color, documents justice (e.g. nature photography, comic books and graphic novels, well illuminated manuscripts) will never come to fruition. Barring some kind of transformative breakthrough, of course.

colour printing is often made from randomised dot screens, so long as they are small enough its fine.

https://upload.wikimedia.org/wikipedia/commons/thumb/a/a6/Co...

Rods in eyes aren't on a regular grid anyway, why should it matter how the pixels are distributed as long as they cover the plane and are mostly uniform?

Because of what was mentioned way up in the original question: The capsules not being precisely arranged means that they can't be individually addressable. Meaning that you can't use the trick that non-epaper screens typically use where each "pixel" is actually a tightly packed cluster of individual red, green and blue sources that are individually controlled.

So instead, each cell is capable of displaying any color, and they've got a more complicated refresh mechanism that they use to "write" to them.

And the upshot of that is listed in the specifications from the linked page: The refresh time on this display is 15 seconds. Which is far, far away from where it would need to be in order to be a practical option for color e-readers.

Except you can do multiple colors, by introducing differently charged pigments inside the capsules:

- https://www.eink.com/assets/img/technology/GIF_Cup_E.gif

- https://www.eink.com/assets/img/technology/GIF_ACeP_E.gif

Refresh rate was always an issue, but it is gradually improving. For static reading it's not a problem.

> Meaning that you can't use the trick that non-epaper screens typically use where each "pixel" is actually a tightly packed cluster of individual red, green and blue sources that are individually controlled

If there was a way to mix the inks and have them 100% separate by the grid on demand, it could be possible.

I have the 2.7” 3 color (b) hat, and it is very slow with stock code. As far as I know, and from the looks of the Python code, 2 full buffers are transferred for the colors and then a process of wave stimulating the fluids into arrangement are how it works, very conservatively and slow. There has been work done to the firmware to allow partial updates fast enough for animation, but they should be used sparingly to avoid temporary or permanent burn-in, they say.

Who designed these ‘eye’ things anyway, sounds like they took a lot of engineering shortcuts and amassed a metric boat-ton of technical debt

Let it thus be observed that a truly intelligent designer understands how to live comfortably with technical debt.

If I was all-knowing and omnipotent, I'd be OK with that in my code as well.

Isn't tech debt a sign of not being all knowing and omnipotent?

I don't know.

There's always tech debt. It starts to day you build something and ends when it stops being used. How many thousands of python 2.7 programs had "no" tech debt when developed bit now have tons. Tech debt isn't binary, it's a sliding scale.

If you were "all knowing", you would've known that Python 3000 would not be backwards compatible and waited until it is released (assuming that you don't have a deadline, such as 7 days).

Even if you had a deadline, you'd know all tech debt and could anticipate it beforehand.

You mean all the Python programs started before 2008, right? Because that's when it was announced that they were sunsetting Py2.

So any projects started since 2008 that were written without Py3 compatibility had known tech debt they were choosing to take on.

Yes. Why does it matter than the particular example I chose had a cutoff date 2008? It's the same issue with any language, program, platform, OS, etc. Even if you implement the latest stable version of any of these things for any project, tech debt begins immediately. In fact if you're dealing with established enterprise software, you know right away what the roadmap & minimum end-of-life is from the day it's released. (as side topic, that's part of why mediocre enterprise software is often chosen over newer better options: because predictability is valued over the newest/best/fastest that may be subject to disruption if the vendor goes away or gets acquired-- something I've seen happen a few times. A vendor gets acquired, we get a "Hey Great News!" message from them along with an "Oh by the way our new parent company is transitioning everyone off our platform to their own completely different offering over the next 6 months, hope you have the capacity/bandwidth to deal it #sorry-not-sorry"

> over the next 6 months

My point is this is a very different situation from the Python 2->3 transition.

If you have 12 years' notice to make some changes, I don't consider that technical debt: that's the normal price of maintaining software in a changing world. It's not "debt" that costs "extra interest" to pay back for questionable choices made previously.

The joke is (and it is a joke, mind you) that an omnipotent and omniscient entity could have written a perfect program in, say, 2005, and it would have no tech debt now, because it's never needed to change since it was written to anticipate every need for the program in the first place.

Hell, since the writer was omnipotent and omniscient, the code was even built with the ability to perfectly modify itself when the company changed the DB on September 12, 2011 at 3:24 in the morning.

Seems like a classic-style omnipotent god could write anything conceivable in some eternal Lisp dialect that he maintains personally. If he’s really capable of violating thermodynamics he should be able use knowledge of the future to ultra-waterfall the design and implement it flawlessly thereby completely avoiding accumulation of technical debt.

It’s fun to imagine Jesus returning in 30xx AD but this time instead of absolving the world of its accumulated sin he wipes away the accumulated technical debt of 1.5 millennia worth of corporate IT

Let me introduce you to the fall of man.

No. Tech debt, like money debt, can be taken on in purpose to be able to take advantage of a short term business opportunity.

The joke is (and it is a joke, mind you) that if you're all knowing and omnipotent, there's no such need to take on tech debt. Because you will have already known about the short term business opportunity and coded it (without tech debt since you also know all of the requirements, pitfalls, and corner cases perfectly) before it was needed.

"How did we justify this whole 'cancer' thing being SEV-1? I really don't see the urgency."

It's what happens when your rookie engineer leans too heavily on generative design instead of doing their homework. :P

Product management kept changing the requirements!

I think the solution is a dual eink and oled display. Overlay a “transparent” oled on top of an epaper screen and use the oled to display colour images and video while using the epaper for static monochrome regions.

I’m not sure that current “transparent” oled technology is transparent and thin enough though.

This sounds really similar to https://www.mobvoi.com/us/pages/ticwatchpro which is a Smartwatch with a dual layer display, one of them is e-ink, the other is an AMOLED display.

Do a search for hybrid eink LCD display; Apple and others were looking into this 10 years ago; the Pixel Qi's 3qi displays were apparently manufactured and used in at least some products, then Apple applied for a more complex patent as well. As far as I can tell, both systems seem to use a layered display.

https://www.pcworld.com/article/165724/bye_bye_kindle_netboo...

https://arstechnica.com/gadgets/2011/04/apple-exploring-hybr...

eink should die already. There are other options rather than eink, microLED and some of the newer low refresh LCDs (Clearilk comes to mind) should be much better. https://www.displaydaily.com/article/press-releases/clearink... Lenovo is interested and made a thinkpad with eink so it shouldn't come from a weird no name company in the future.

Do the others ones not consume power when you don’t need to change the display, are legible in daylight, or otherwise not emit light?

These are unique advantages to e-ink as far as I’m aware.

It doesn't matter for a stationary screen

It certainly does depending on your application. Grocery stores use them for prices where you wouldn't want a glow and low power means you can run off a battery. If I integrated into my walls as a smart device I would want a subtle design without a glow. These are just two examples off the top of my head. The application matters.

Also where did this stationary context come from?

People are asking about using it as a monitor in the comments. Grocery stores can do wireless power but the comments are complaining about them being too big or small.

You can easily have a non backlit black and white display, like the one on an f91w or LCD clock.

The contrast ratio will never make it good for text. I have used the so called high res ones and I would take a 720p LCD any day. They are trash.

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