Troubleshooting It doesn't look like a scratch...?

[geekmaster]

Originally Posted by Jessica Lares

So, in order for this NOT to happen again, what are some suggestions? Besides putting on a screen protector?

I wonder if the capsules can expand and pop if they get too hot? I would think that the glass evenly distributes low-impact force and the beads are more flexible than the glass. It seems that the glass could break long before popping a capsule. Perhaps pressing on the glass can pop them without cracking the glass though. Just guessing here.

P.S. I prefer "bead" over "capsule" because it is easier to type on my onscreen tablet keyboard. And beads are small, a capsule is something you stick on a rocket, and I love rocket-science.

@andyh2000: Thanks for the photo that shows what I was trying to describe. That "multiple pixels per bead" thing is something I hadn't seen before. Perhaps that is used on the new higher-resolution Paperwhite kindle. Awesome!

[Popup]

Originally Posted by geekmaster

@andyh2000: Thanks for the photo that shows what I was trying to describe. That "multiple pixels per bead" thing is something I hadn't seen before. Perhaps that is used on the new higher-resolution Paperwhite kindle. Awesome!

I thought it was the other way around, with multiple 'beads' per pixel, but it looks like it's rather one bead/pixel.

That eink link claims that 'Electronic ink is made up of millions of tiny microcapsules, about the diameter of a human hair.' Now, the diameter of human hair varies a lot, but 75μm seems like a reasonable estimate. The Paperwhite is supposed to have a 212ppi display, which would mean 120μm/pixel - larger, but the same order of magnitude as a hair's breadth.

[geekmaster]

Actually, macro photos show the beads as randomly placed with multiple per pixel. There is a photo I posted here in a thread comparing fonts or displays... The image you posted is a simplified diagram that may only be correct for beads sitting across a boundary, or perhaps on "high resolution" displays.

[geekmaster]

I found the image that shows many beads per pixel:

The square blocks in the image are pixels. The much smaller randomly distributed "round spots" are beads (capsules). The beads are a little hard to see because they are all the same color, but you can slightly see their edges.

Also, you can see some "snow" where some dark particles are still stuck to the front surface of some beads. Doing three full refreshes or more knocks those stuck particles loose and results in a higher contrast display.

If there were only one round bead per pixel, you would not see such sharp corners on the pixels.

However, higher resolution displays MAY use smaller pixels with the same sized beads.

I think that the simplified artistic diagram was just drawn to demonstrate how the technology works, and not to show relative scale between beads (capsules) and pixels.

P.S. The above photo also shows the visual effect of different fonts. Gray pixels can help around the edges, but letter strokes must be black "inside" to prevent poor contrast.

[Popup]

Thanks geekmaster! That confirms what I thought.

Is there any hard information as to what technology the PaperWhite uses? Is it just a scaled-down version of the Pearl screen?

[geekmaster]

The beads (capsules) just keep the charged particles (chips) from migrating around, so they stay evenly distributed. It probably does not matter whether there are multiple beads per pixel, or multiple pixels per bead. Only the pixel addressing grid on the back surface of the eink screen matters, regarding pixel placement and pixel density.