HUGE E-Ink Tablets!

[Sil_liS]

Originally Posted by toronado

To my understanding that is not a full refresh, and will eventually cause ghosting issues unless a full refresh is done periodically. Please correct me if I'm wrong.

Full refresh means flashing to inverse. How else are you going to refresh a white pixel between lines of text?

[rkomar]

Originally Posted by Sil_liS

Full refresh means flashing to inverse. How else are you going to refresh a white pixel between lines of text?

I don't follow. Why does it matter what adjacent pixels are set to? I always figured there was some kind of resistance in the rotating cells that made small changes difficult to control, so a flash to inverse was required for better control of the final position. But that was just a guess. I vaguely recall that you had taken movies of the display with a microscope in the past, so you probably have a good idea of what it's doing. Can you give more details?

[Sil_liS]

Originally Posted by rkomar

I don't follow. Why does it matter what adjacent pixels are set to? I always figured there was some kind of resistance in the rotating cells that made small changes difficult to control, so a flash to inverse was required for better control of the final position. But that was just a guess. I vaguely recall that you had taken movies of the display with a microscope in the past, so you probably have a good idea of what it's doing. Can you give more details?

You know this kind of diagram:


But I think that this is more accurate from the point of view of the distribution of the particles (but wrong on the point about the charge of the black particles, as the black particles are positive charged, not neutral):

But it still isn't accurate enough. The charged pigments would also be under the influence of voltage applied to the adjacent pixel, and not just the one directly under the capsule. So naturally the distribution of pigments in the middle of the capsule would be more homogenous for the capsules at the edge of the pixel.

If in the image above you apply negative voltage under the right two capsules the pigments are going to migrate, but there won't be a big difference in the adjacent capsule (second from the left) since the white particles on top are not going to move and the black particles in the middle are going to be shielded to some extent by the positive charges of the black particles that are already at the bottom.

In this way what you see on the screen (if you zoom in) will be white circles surrounded by grey as at the top of the capsules there will be white particles but you would also see around them the middle distribution. The capsules that have been directly adjacent to previously black pixels are going to be white on top but surrounded by darker grey. And this will be the ghost that will show the contour of whatever black shape was on the screen and then turned white.

Someone made a video of this where the screen doesn't flash to reverse:


How much ghosting one sees will be dependent on the choice of font, size of text, whether the text is anti-aliased or not.

[rkomar]

Thanks! It works quite differently from what I thought I understood from old cartoons. I was under the impression that the pigment was more or less fixed in the gel with the black and white on opposite sides, and that the gel spun around as a whole within the cell. Clearly, that's not what is happening.

I'm also still not clear about why the ghosting remains. Even if there is some gray in the white cells next to black ones in the original image, why don't they just become white when the next image is displayed? Does the display not try to change pixels whose value hasn't changed? Or, as I mentioned in my last message, is it a case of some kind of internal resistance not allowing such fine-grained control?

[JSWolf]

That's why you have a flash after so many screen refreshes with no flash in order not to have ghosting that's too noticeable.

[toronado]

Originally Posted by Sil_liS

The capsules that have been directly adjacent to previously black pixels are going to be white on top but surrounded by darker grey.

Wow, thanks for posting that video. It explains a lot. At the end of the video (around 0:44) you can see a swelling and contracting of the edge of the shape (font/character) being displayed. The amount of size fluctuation seems roughly equivalent to the width of the "ghost" outlines that appear when they are running that number counter.

Appears something is "bleeding" around the edges there that is not being controlled. If the technology could be developed that would control this more precisely, perhaps the ghosting could be completely eliminated.

As it is, this technology seems fundamentally flawed. Sorry if I'm being too much of a perfectionist, but that's just the way it seems to me.

[Sil_liS]

Originally Posted by rkomar

Thanks! It works quite differently from what I thought I understood from old cartoons. I was under the impression that the pigment was more or less fixed in the gel with the black and white on opposite sides, and that the gel spun around as a whole within the cell. Clearly, that's not what is happening.

I'm also still not clear about why the ghosting remains. Even if there is some gray in the white cells next to black ones in the original image, why don't they just become white when the next image is displayed? Does the display not try to change pixels whose value hasn't changed? Or, as I mentioned in my last message, is it a case of some kind of internal resistance not allowing such fine-grained control?

If you apply a voltage between two plates and place a charged particle between them the particle would move towards the plate with the opposite charge with a constant acceleration which is proportional with the strength of the electrical field between the plates. For example you would have negative charges on one plate, a negatively charged particle and positive charges on the other plate so the particle moves away from the negative charges on one plate and towards the positive charges on the other plate. In the case of eink you have many charged particles between the plates and they will have an effect on the strength of the field.

In the case of ghosts you had the charges move between the plates so if you apply the same voltage you have negative charges on a plate, positive charged particles inside the capsule on that side of the plate, a mixture of positive and negative charged particles in the middle, negative charged particles on the other side of the capsule then the positive charges on the other plate. The particles in the middle are going to move very slowly towards the plates with the opposite charge because in effect the electric field is lower.

If you apply voltage with the opposite sign, then the charged particles on the side of the plates will have the the same signs as the charges on the plates and the charged particles will be under a stronger field and move faster.

Originally Posted by toronado

Wow, thanks for posting that video. It explains a lot. At the end of the video (around 0:44) you can see a swelling and contracting of the edge of the shape (font/character) being displayed. The amount of size fluctuation seems roughly equivalent to the width of the "ghost" outlines that appear when they are running that number counter.

Appears something is "bleeding" around the edges there that is not being controlled. If the technology could be developed that would control this more precisely, perhaps the ghosting could be completely eliminated.

As it is, this technology seems fundamentally flawed. Sorry if I'm being too much of a perfectionist, but that's just the way it seems to me.

It is flawed now, but it can be improved.

[rkomar]

Originally Posted by Sil_liS

If you apply a voltage between two plates and place a charged particle between them the particle would move towards the plate with the opposite charge with a constant acceleration which is proportional with the strength of the electrical field between the plates. For example you would have negative charges on one plate, a negatively charged particle and positive charges on the other plate so the particle moves away from the negative charges on one plate and towards the positive charges on the other plate. In the case of eink you have many charged particles between the plates and they will have an effect on the strength of the field.

In the case of ghosts you had the charges move between the plates so if you apply the same voltage you have negative charges on a plate, positive charged particles inside the capsule on that side of the plate, a mixture of positive and negative charged particles in the middle, negative charged particles on the other side of the capsule then the positive charges on the other plate. The particles in the middle are going to move very slowly towards the plates with the opposite charge because in effect the electric field is lower.

If you apply voltage with the opposite sign, then the charged particles on the side of the plates will have the the same signs as the charges on the plates and the charged particles will be under a stronger field and move faster.

I guess this makes sense if you assume that they apply some voltage for some specific amount of time that is tailored to shift a pixel from one grayscale value to another. If the pixel is actually displaying a different grayscale colour to start with than the driver thinks it should be (like in the ghosted regions), then the resulting pixel colour will be wrong. A full refresh means driving each pixel to full black or full white (i.e. a known state), and then applying the fine-tuned electric field to produce the final desired grayscale colour value. Does that sound right?

[rkomar]

Originally Posted by Sil_liS

If you apply a voltage between two plates and place a charged particle between them the particle would move towards the plate with the opposite charge with a constant acceleration which is proportional with the strength of the electrical field between the plates. For example you would have negative charges on one plate, a negatively charged particle and positive charges on the other plate so the particle moves away from the negative charges on one plate and towards the positive charges on the other plate. In the case of eink you have many charged particles between the plates and they will have an effect on the strength of the field.

In the case of ghosts you had the charges move between the plates so if you apply the same voltage you have negative charges on a plate, positive charged particles inside the capsule on that side of the plate, a mixture of positive and negative charged particles in the middle, negative charged particles on the other side of the capsule then the positive charges on the other plate. The particles in the middle are going to move very slowly towards the plates with the opposite charge because in effect the electric field is lower.

If you apply voltage with the opposite sign, then the charged particles on the side of the plates will have the the same signs as the charges on the plates and the charged particles will be under a stronger field and move faster.

I guess this makes sense if you assume that they apply some voltage for some specific amount of time that is tailored to shift a pixel from one grayscale value to another. If the pixel is actually displaying a different grayscale colour to start with than the driver thinks it should be (like in the ghosted regions), then the resulting pixel colour will be wrong. A full refresh means driving each pixel to full black or full white (i.e. a known state), and then applying the fine-tuned electric field to produce the final desired grayscale colour value. Does that sound right?

[Sil_liS]

Originally Posted by rkomar

I guess this makes sense if you assume that they apply some voltage for some specific amount of time that is tailored to shift a pixel from one grayscale value to another. If the pixel is actually displaying a different grayscale colour to start with than the driver thinks it should be (like in the ghosted regions), then the resulting pixel colour will be wrong. A full refresh means driving each pixel to full black or full white (i.e. a known state), and then applying the fine-tuned electric field to produce the final desired grayscale colour value. Does that sound right?

They do apply some voltage for some specific amount of time that is tailored to shift a pixel from one grayscale value to another. That is why the screen only uses energy when there is a page turn.

One thing is that a pixel is more than one capsule, and the other is that the image in the video is supposed to be black and white, not grayscale. The fact that the pixels are gray on the edge is due to being adjacent to a pixel that had been black. It is faster to make everything white by applying the reverse voltage first and then the correct voltage than if you would wait for the ghost to disappear.

[Sil_liS]

[rem736]

with the price of the sony 13.3" being over $1K, i may actually consider the samsung galaxy note pro 12.2". the intention is to read pdfs full screen with little or no reduction in the size of the page. i think the samsung 12.2 fits the bill. this will not be for pleasure reading, but for research/technical reading. pleasure reading will remain on a smaller e-ink device. but i think i will wait til december to decide to take the plunge. prices will drop. we just don't know by how much.

[toronado]

Originally Posted by Sil_liS

YouTube video

$20-$50 million loss per quarter? Is it just a matter of time before this technology goes bye bye, or will they be able to stay afloat doing commercial signage etc?

[Sil_liS]

Originally Posted by toronado

$20-$50 million loss per quarter? Is it just a matter of time before this technology goes bye bye, or will they be able to stay afloat doing commercial signage etc?

I'm hoping it's the latter.

[rem736]

i actually purchased the samsung galaxy tab pro 12.2 from the local costco and tried it out for just one afternoon before i finally decided that it wasn't up to par and returned it the next day.

for some reason, they have the home button programmed to bring up google search every time it's touched. and with the home button slightly raised from the main surface, i ended up touching it a lot with my thumb when holding it portrait mode for viewing. not only that, it also seems that the unit has been programmed to bring up google search every time you shake it. that's fine, but i swear i wasn't shaking it. every time i move it around, google search pops up, hindering whatever i was trying to do. putting it on a table, if i happened to bump against the table, google search would pop up. and as far as i could see, there's no way to change the behavior of the home button. and shouldn't it just go to the home screen by default? to get to the home screen, you have to touch the home button twice.

the other thing that infuriated me and had me deciding to return it was that when i was scrolling up and down the sd cards directory to open up a book via the aldiko app, it would close every time i try to open up a directory. it would also close every time my scrolling reached the bottom of the list.

i got so frustrated that i never actually opened up an ebook to see what it would look like. i just reset it, charged it overnight, and returned it the next day.

google, if you are listening (or crawling this web page), please make a 12-13 inch version of the nexus tablet.