Feeds

back to article Ricoh reveals paper-bright colour e-paper

Here's a snap of Ricoh's colour e-paper, which, the company claims, is two-and-a-half times brighter than anyone else's colour e-paper. There's not much colour e-paper out there at the moment, you may have noticed, so Ricoh's boast is a mite hollow. Ricoh e-paper It also reckons its offering has "about four" times as wide a …

COMMENTS

This topic is closed for new posts.
Thumb Up

CMYK

It makes perfect sense for this type of display. Hopefully some Ricoh boffins are enjoying a big pay rise for this one.

0
0

Sensible

Using CMY instead of RGB makes a lot of sense. There's a reason people use it for printing. Full CMYK would make even more sense, and would probably be fairly easy to add.

1
0
Silver badge

RGB v CMY

Although I've sort of followed the development of e-ink/e-paper with some interest, I've never really looked at the underlying technology.

This article has surprised me in that existing colour e-ink/e-paper is using RGB while Ricohs new offering is CMY.

Since e-ink/e-paper relies on reflective not emitted light I'd have assumed they were all using CMY colours. Ir's the difference between additive and subtractive colour mixing.

Of course, I may be making incorrect assumptions here. No doubt a master printer will be reading and correct me if I'm wrong ;-)

Whatever the whys and wherefores of the underlying technology, it's still another step forward to the day when I can walk into the local DIY shop and buy some rolls of active wallpaper and decorate for the very last time. Next time the wife changes her mind over the colour scheme, she can push the damned button and change it.

0
0

Re: RGB v CMY

I think the picture explains this one. Their system uses subtractive colour mixing (CMY) because there's a reflector at the back, so the reflected light is being filtered by the active layers (presumably in both directions). Other systems use additive colour mixing (RGB) because it's the active layers that are doing the reflecting - the background is dark. I can only assume that others have found it easier to reflect light rather than filter it up until now.

0
0
Thumb Up

"Ricoh's boast is a mite hollow."

No it isn't. If other techs exist and this beats them then that's progress and the developer has every right to boast.

5
0

Page speed?

How long do page changes take?

1
0
Anonymous Coward

Can you say Contrast Ratio..

Its white is whiter than white, but is its black white too?

All well and good boasting about its reflectivity.. but how about the opposite??

2
0
Silver badge

Indeed.

When I read it was CMY, my initial though was, "Other's aren't?", followed by, "where's the K"?

0
0
Silver badge
WTF?

Woah, you mean colour E-paper wasn't CMY before?

Glory be, those guys with the RGB one are superlative idiots.

When was the last time you saw an RGB printer? Colouring a surface *does not work that way*.

I hereby claim the idea of "CMYK" E-paper.

I also claim CcMmYyK (Light and dark of each secondary colour) and any combination thereof which would give different gamuts at various price points.

This is now my idea, and I release it for free because I want every e-paper manufacturer to use it, unencumbered by stupid patent trolls trying to claim the bleeding obvious.

4
0
Happy

Remember when lasers were laughed at?

... as the solution waiting for a problem?

e-paper seems to be in that that situation now. I'm happy for them One day it'll be as iniquitous as lasers are now and we'll be wondering how we ever lived without it.

Just wish they'd get a move on.

1
0
Bronze badge
Headmaster

The word you're looking for...

...is 'ubiquitous'.

That is all.

2
0
Terminator

maby not

mabny it is Innocuous and he knows somthing you don't?

0
0
Silver badge

Well lasers are pretty wicked.

And cool.

But only in a metaphorical sense.

0
0

Obvious

So...just the same as colour printing then, albeit with the absence of a pure black key.

How did everyone else get it so wrong? Presumably they were trying to reuse existing LCD screens designed for backlit displays.

0
0
Silver badge

Subtractive coloring...

Actually, a rather novel but sensible approach to the E-ink problem since that's the same color system printers (of all sorts) use. The catch is that most color picture files today use additive coloring (RGB), so some conversion will be necessary for color e-books to appear correctly on a Ricoh screen. There's also the matter of refresh rate. Something tell me this is strictly an e-book material and not one that refreshes quickly enough for multimedia uses.

0
0
Silver badge

Don't think the processing will be that hard.

I've done some pretty good approximations for RGB->CMYK->RGB conversions in Javascript before now. As the screen itself is probably going to have an awful refresh rate anyway, you could probably get away with some cheapo embedded microcontroller that costs about 5p when bought in bulk.

0
0
Silver badge
Boffin

No catch, RGB to CMY is a solved problem.

You can get a reasonable approximation by using Cyan = Not Red, Magenta = Not Green, Yellow = Not Blue.

The better algorithms take account of the particular bandwidth of each of the specific CMY filters in use.

You'll find the algorithm in your printer driver. Even the really good ones are trivial to process.

That's even before you realise that almost all the imagery this is intended to be used with is stored in CMYK format already, as that's what was used to make the 'real' book!

0
0

no black?

Surely having a K to make up CMYK would yield a better black. That picture doesn't look that fantastic contrast wise.

1
0
Bronze badge
Thumb Up

CMY

Seems so obvious given that the display is subtractive, without a Key (Black), layer though text is going to look a bit ropy.

Overall I'm impressed with this tech, hard to imagine just how interactive my kids future is going to be when this stuff is made into cereal boxes.

0
0
Anonymous Coward

@jubtastic1

I strongly suspect you'll just get Ocean Finance adverts on your breakfast table.

It might revitalise the adult art pamphlet market though.

0
0
Silver badge

Needs a K layer

While it is sensible to use CMY instead of RGB for a reflective medium, they really need to add a K layer, or black print is going to look rather muddy.

Early colour inkjet printers (Canon, I think), didn't have any black ink and produced blacks by blending CMY. The result was text that looked a sort of muddy brown, which is just what you don't want for an eBook where the clarity of the text is the biggest advantage eInk has over LCD.

1
0

K?

The reason for using K is because of impurities in the inks, as well as registration issues. If the colors are close to perfect, then theoretically a nice black (and greys) would be possible without using anything other than CMY, and of course registration isn't a problem here.

1
0
Gold badge

Sub-pixels

I like the way that this looks like the sub pixels are all on top of each other instead of next to each other as for normal colour displays. I suspect that could make the biggest difference as to how easy on the eye colour e-ink displays are compared to "normals". I think that seeing a full single colour pixel instead of 3 different brigtness RGB sub-pixels near each other will really help.

As for CMY instead of RGB, it all depends on how their layers work. Obviously the RGB boys have layers that reflect that colour when activated, so even though the display is reflective, the different bits that are reflected add, hence RGB. Ricoh's layers obviously attenuate when activated and so are subtractive.

As far as black is concerned, it all depends on how attenuative their layers are, like my LCD TV which despite having a claimed contrast of 100000000000:1, can't do black unless I turn it off.

1
0
Silver badge
Headmaster

Subtractive vs Additive

LCDs are clear or Black. So don't work in three layers of CYM. Hence they have to have additive dots side by side. Each dot has to block entirely cyan (leaving red), magenta (leaving green) and yellow (leaving blue) wasting at least 2/3rds of the backlight. Real LED displays (like fill a wall) are Red, Green and Blue LED dots. AMOLED are really yellow or UV/Violet (with phosphor to get white), Most have LCD style RGB filters.

To use CYM you need a display that each element is coloured or transparent. The mono eInk in kindle etc uses tiny balls that are black on one pair of faces and white on the other, so they have to to use RGB filter additive side by side for colour which makes them VERY dim.

They must be using a liquid dye type display, each cell is empty (clear) or filled with cyan, yellow or magenta liquid. Parallax is an issue unless the cells are very much thinner than they are wide and high. OTH each cell can be 3x bigger than the RGB additive technique. Or twice as big for additive RGB arranged

RG

GB

for 2 x2 subpixel instead of older 3 x1 RGB stripes.

2
0
tas

So when do I get my Kindle Color?

I may actually be tempted to buy an e-reader if it supported color e-Paper/e-Ink, as long as it also had full support for reading PDFs, e.g. re-flow and font scaling on sub-A4 displays and a fast enough page refresh/turn that didn't kill my visual cortex after ten minutes.

Actually, bugger that for a lark, I'll take any e-Ink/e-Paper reader that actually has full PDF support, even if it is just black and white. Yes, I'm in Europe, so even the next best thing, a Sony PRS-950, is out of the question ...

0
0
Big Brother

We dont need no stinkin' title!

Unless the reader software can reflow the PDF to comfortably fit the display area of the reader (and I've not yet seen one that can) then they are intrinsically unsuited to each other. IMO and it is just an opinion albeit based on experience I would say if PDFs are much better viewed on a <Insert favourite tablet here>

0
0
Silver badge

Kindles support PDF's

Not sure how 'full' the support is though - but I haven't had any problems reading the ones I have tried.

0
0
Silver badge
Boffin

The whole idea behind PDF

was the elimination of the very end-user orthogonality you're talking about. Back in the 90s, HTML was designed to be orthogonal to the user - that is, the user had control over the text flow, colours, layout and so on. If the page author created his page in 8 pt black Arial with images floating to the left and you wanted to view it in 72 pt pink Garamond with non-floating images, there was nothing he could do about that. Consequently it was difficult for designers who wanted fixed-format, predictable document layouts to achieve that in HTML. Adobe, seeing a market for a fixed-layout document format that removed any end-user control over presentation, invented PDF for that very reason.

So PDF is not designed to appear any way other than the author intended it to. Ironically, HTML, which is a format that would have lent itself perfectly to ebook formatting back in the 90s, is becoming, in its current designer-oriented incarnation of HTML 5 and CSS 3, more restrictive of end-user orthogonality than PDF is!

0
0
Go

Digital Photos

Can't wait for this to make it to digital photo frames. It would be great to be able to just plug it in when you want to change the picture - or even better - run it for 6 month from a button cell.

0
0

colour, schmolour

one of the reasons I haven't got me a Kindle-type device yet is the GREYness of it all. The contrast in the new Ricoh display looks much better, colour or not.

0
0

Ricoh

Just a fast word about Ricoh, who ALWAYS go against the tide, against the grain, and usually end up with something niche, and utterly cool, such as their compact but pro quality cameras. I have no stock, no affiliation, but I just LOVE a company that can find niches and work to exploit them against their bigger rivals. Ricoh has guts...they ought to relocate to Silicon Valley...

0
0
This topic is closed for new posts.