E Ink Waveforms are a closely guarded secret • Hacker News Board

Re: E Ink Waveforms are a closely guarded secret

#51

Post by mikekchar » Sat, Sep 15, 2018, 11:00 AM UTC

tigershark wrote: post #22

chaoxu wrote: post #17

Recently, I brought a Dasung paperlike HD to use as a monitor. (crazy expensive, prob should've spend money elsewhere...) I thought some things were impossible with eink, but it proved me wrong. (video in a reasonable fps) It has a few different ways of display. For example: Floyd–Steinberg dithering: essentially only black and white with dithering, and the speed pretty good. A16: uses 16 shades of grey, but the spee…

Why would you use an e-ink display for videos? The main advantage is the low power consumption because it needs power only to refresh, using it for a video it will negate that advantage and draw much more power than a traditional display with an awful image quality...

Not the OP, but the main reason I want an e-ink display (for programming, which may include animations) is so that I can do it in full sunlight. I work remotely and often work in public places. Working on a park bench, for example, is normally impossible, unless it happens to be cloudy and I'm in a shady place. I'm just hoping e-ink becomes a mainstream thing before I retire.

Re: E Ink Waveforms are a closely guarded secret

#52

Post by dukoid » Sat, Sep 15, 2018, 11:07 AM UTC

chaoxu wrote: post #17

Recently, I brought a Dasung paperlike HD to use as a monitor. (crazy expensive, prob should've spend money elsewhere...) I thought some things were impossible with eink, but it proved me wrong. (video in a reasonable fps) It has a few different ways of display. For example: Floyd–Steinberg dithering: essentially only black and white with dithering, and the speed pretty good. A16: uses 16 shades of grey, but the spee…

I have done software screen mirroring for RTL languages on an Atari ST ages ago. There I had both full images available and I'd just compare source and target rows, skipping 8 rows (IIRC) until detecting change, in which case I'd swap the local area. The start row was incremented after every scan, so I'd be sure to not have missed any pixel after 8 scans. This allowed to track the mouse quickly and also to respond to local changes (text editing) without letting the mirroring thread fully lock up the computer.

For your case, it seems more reasonable to divide the screen into some kind of rectangular cells, keep checksums for the cells and switch them to A16 if the checksum stays constant for two visits? This would avoid the need for a full extra frame buffer while still being relatively accurate. I think one main problem will be that you'd need to modify the screen firmware to do something like that. Probably would make sense to code a software emulation on a regular screen to see what it would look like...

Re: E Ink Waveforms are a closely guarded secret

#53

Post by etaioinshrdlu » Sat, Sep 15, 2018, 11:14 AM UTC

Seems like a good use case for PID loops -- drive the pixel really hard for a brief moment to bring it to the target value faster than might otherwise be possible.

Seems limited only by the voltages that just end up frying parts.

Re: E Ink Waveforms are a closely guarded secret

#54

Post by amelius » Sat, Sep 15, 2018, 11:15 AM UTC

sofon wrote: post #42

userbinator wrote: post #3

Is it really "closely guarded", or "worst guarded"? Anyone with a logic analyser and a few hours can probably figure it out easily enough... and some have even gone beyond what the official controllers can do: https://hackaday.io/project/11537-nekocal-an-e-ink-calendar/... (previously discussed at https://news.ycombinator.com/item?id=16140284 ) More research from others: http://essentialscrap.com/eink/ https://news.y…

The waveforms will all likely be disclosed in their patents too: https://patents.google.com/?assignee=E+Ink+Corp Certainly a number of drive waveforms and the basic concepts are presented. There are likely implementation subtleties or specific configurations that are not explicitly disclosed. You can probably figure out a lot about both the implementation, and motivation by digging through the patents.

Yes, it would be quite stupid to guard the secret and not patent it. So the title of the article doesn't make much sense.

Re: E Ink Waveforms are a closely guarded secret

#55

Post by petercooper » Sat, Sep 15, 2018, 11:19 AM UTC

chaoxu wrote: post #28

vackosar wrote: post #23

Earlier quoted context omitted.

What fps do u get on those modes?

I don't have an easy way to measure the FPS, but here is a video I just took. https://www.youtube.com/watch?v=xW-gatdEC7w It is reasonable enough to see what's happening, but obviously, I'm not going to watch a movie on that.

I measured 5 fps in that video - surprisingly good from what I understood of eink :-)

Re: E Ink Waveforms are a closely guarded secret

#56

Post by Avamander » Sat, Sep 15, 2018, 11:27 AM UTC

ehead wrote: post #48

robin_reala wrote: post #20

Earlier quoted context omitted.

I’ve never seen one in real life. How are the display characteristics compared to eInk?

If you’ve ever seen an OG Pebble, you’ve seen that display. It looks like a better resolution gameboy display. Very little space between pixels. Some models are different, though, and basically turn into a mirror when their pixels are turned on, rather than become matte black. Adafruit sells a dev board for 25 bucks. Perfect for low power wearables, much better than E Ink.

I disagree that memory LCD is better than e-ink. Although, mLCD can do colors and better refresh rates but the colors are washed out, in sunlight grayscale e-ink is much much more readable in my opinion. mLCD also consumes more power in certain cases which isn't ideal.

Re: E Ink Waveforms are a closely guarded secret

#57

Post by wingspar » Sat, Sep 15, 2018, 11:32 AM UTC

amelius wrote: post #54

sofon wrote: post #42

Earlier quoted context omitted.

The waveforms will all likely be disclosed in their patents too: https://patents.google.com/?assignee=E+Ink+Corp Certainly a number of drive waveforms and the basic concepts are presented. There are likely implementation subtleties or specific configurations that are not explicitly disclosed. You can probably figure out a lot about both the implementation, and motivation by digging through the patents.

Yes, it would be quite stupid to guard the secret and not patent it. So the title of the article doesn't make much sense.

That’s done all the time. Called a trade secret. https://wikipedia.org/wiki/Trade_secret

Re: E Ink Waveforms are a closely guarded secret

#58

Post by bonzini » Sat, Sep 15, 2018, 11:36 AM UTC

mrob wrote: post #37

chaoxu wrote: post #25

Earlier quoted context omitted.

1. Currently, I use it for writing code and reading papers. However, I still want the monitor to be a good enough drop-in monitor for things I need to occasionally do. For example, I need to switch to a browser window to check what was that error I'm getting. 2. Visual snow syndrome: Many had their first experience of visual snow after staring into the screen for too long. People who believe in that is the cause of v…

What exactly about emitted light is a problem? Light doesn't carry a memory of how it was generated, so it must be some difference in some measurable property, e.g. brightness/contrast/color spectrum/flicker/polarization, or the way these change at different viewing angles. If you know which attributes are important then you might be able to match them with an emissive display.

Staring directly at a light source strains the eyes more than watching reflected light.

Re: E Ink Waveforms are a closely guarded secret

#59

Post by amelius » Sat, Sep 15, 2018, 11:42 AM UTC

wingspar wrote: post #57

amelius wrote: post #54

Earlier quoted context omitted.

Yes, it would be quite stupid to guard the secret and not patent it. So the title of the article doesn't make much sense.

That’s done all the time. Called a trade secret. https://wikipedia.org/wiki/Trade_secret

As others said, it's quite easy to measure these waveforms, and they have a patent. So "closely guarded secret" just doesn't make sense in this case.

Re: E Ink Waveforms are a closely guarded secret

#60

Post by mrob » Sat, Sep 15, 2018, 11:50 AM UTC

bonzini wrote: post #58

mrob wrote: post #37

Earlier quoted context omitted.

What exactly about emitted light is a problem? Light doesn't carry a memory of how it was generated, so it must be some difference in some measurable property, e.g. brightness/contrast/color spectrum/flicker/polarization, or the way these change at different viewing angles. If you know which attributes are important then you might be able to match them with an emissive display.

Staring directly at a light source strains the eyes more than watching reflected light.

By what mechanism of action? It can't possibly be true in general: e.g. staring at the reflection of the sun in a mirror strains the eyes more than staring at a candle.