Ow they use the pixel sorting of the OLPC XO; diagonal instead of horizontal?
The following respond I originally wrote with the thought in mind that e-ink pixels have only 2 positions: On, or off. With that in mind I wrote the following:
As for the white color pixel, I expect it to be black, since each pixel is either white or RGB (RYB)
It would make no sense to have a white pixel white in on and off position.
Also, the right color mix for passive colors (like on a paper) is Red, Yellow and Blue; as for emitted light like on a tv goes Red Green and blue.
I just tested it, and have this color palette:
1- Red
2- Red+Yellow=orange
3- Yellow
4- Yellow+blue=green
5- Blue
6- Blue+red=purple
7- Red+Yellow+Blue=grey
8- nothing = white
Each pixelgroup can be paired with an additional pixel, being either white or black, resulting in a lighter or darker overall color of the pixel. So that's 16 colors. It is possible to get white, grey and a mix of colors, but impossible to get a deep black color there, unless every RYB pixels is overlayed with a polarization filter and a LCD like screen but with only 2 modes; black or transparent.
So you'll need 2 screens, lose transparency, and contrast, or will have to do with a color ebook that can only display grey as it's closest color to black.
So I guess pixels will be:
R(ed) Y(ellow) B(lue) & W(black) (W for black, to differentiate between B from blue).
So take 2:
RYBWRYBWRYBW
BWRYBWRYBWRY } These row can be used to correct the color of the scanline on the top and/or on the bottom.
RYBWRYBWRYBW
BWRYBWRYBWRY } " " " " " " " " " " " " " " " " "
RYBWRYBWRYBW
BWRYBWRYBWRY } " " " " " " " " " " " " " " " "
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The resultant resolution for a 600x800 screen is 300x400 which is bad but not as bad as you indicated.
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You are right, IF RYBW pixels each can only have an 'ON' or 'OFF' state; meaning IF the total color of the screen is limited to 16 colors.
*Edit: If you want 256 colors either the resolution will be further cut in halve (to 200x300 pix, and I hereby correct my previous mistake of 200x150 pix), or a pixel needs more than 2 states (pref. 4).
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If you consider a 6 bit array of RGB you get 64 colors 2**6. Adding whilte provided additional shades of those 64 colors which is an additional color to the extent that White lightens the color. So if we consider the 4 values of white with the other two bits we end up with 4*64 which is still the full 256 colors. Using 2 bits per pixel takes advantage of the sub-pixel capability of a display as shown at: http://www.eink.com/technology/howitworks.html
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I have to yet find out what you mean with "6 bit array of pixels".
You mean that the technology has 3 bits per pixel instead of 2?
About the link you send:
I thought the technology on the screen of the Sony PRS-505 reader is not this technology, because the screen stays uninfluenced by strong magnetic fields. Yet it does seem to get influenced by sunlight, making it grey.
UV light seems to influence the screen, not really heat or magnetic field; something that wouldn't make sense when the e-ink technology used in the Sony reader would have been the technology displayed on the link you send.
I don't know if the link explains how e-ink works on all devices, but I suspect it is not this technology at work at the sony reader.
So, my question would be if the upcoming e-ink technology will have 3 or 2 bits per pixel. (Or perhaps more?)
2 bits would effectively set the resolution of current 6" 800x600pix models back to 400x300 effective resolution @ 16 colors, and halve that resolution even again for 8bit 256 colors.
3Bit pp. could up the colors to a 81 color, 400x300 effective res, or 243 colors on a 200x300 effective res.
3bit would mean each pixel would have:
1- 0% color (white)
2- 50% color
3- 100%color (RYB, or black)
4bit would bring 256 colors on a 400x300 effective res screen, and give:
0%, 33%, 67%, 100% of color. Each pixel need to have 4 states.
But like said, they need some sort of Calculator polarization filter with 800x600 pix. to overlay and darken the color pixels below, and create the Ebook resolution solely with RYB (leave the fourth B/W pixel).
you'll effectively need 2 layers, that need to be layered perfectly on top of eachother, which would make it harder to create flexible color e-ink screens.
Within such layers one could also create a third touchscreen layer.
I wonder when we're going to get rid of these separate layers, with touchscreen being 1mm away from the LCD, due to a bunchload of other filters, and empty space being inbetween the touch screen and the LCD glass substrate...
Why don't manuffacturers just simply not get rid of all those filters, and empty space, and just get a touchscreen glued on top of the glass substrate? Then there's no need to put an anti-glare layer on top, neither some plastic protection layers or UV/IR filters for the eye, since a touchscreen already has most of these functions built in itself (and is not even necessary for e-ink, only for CRT/LCD screen).