fantastic plastic

Nikkei Electronics Asia has a cover story on the growing market for electronic ink applications.
Apparently E Ink has solved the ‘after-image’ or ‘ghosting’ problem seen in early applications, such as the Sony Librie. Two of the products available (in Japan) since January 2006 are the Seiko E Ink Watch and the Ishida shelf price tag system using SiPix. Electronic ink is ideally suited for such applications with very low refresh rates (e.g. 1 update per second), but in the longer run, we can expect to see it used in more demanding applications such as notebook screens:

In March 2005, Intel Corp of the US disclosed that Intel Capital Corp of the US had invested into E Ink. A source at Intel explained: “About a third to a half of power used in today’s notebook PCs is used by the display. If notebooks could use E-paper it would mean a significant reduction in power consumption, and at the same time provide a big improvement in readability outdoors.”

Regarding the different technologies,

the E-papers expected to reach the practical level in 2006 to 2007 can be broadly divided into the particle-based type from firms like E Ink, SiPix Imaging and Bridgestone Corp of Japan, and the cholesteric liquid crystal type from companies including Asahi Glass, Fuji Xerox Co Ltd of Japan and Fujitsu. Even under a single type category, though, the implementation technology may be widely different, with each manufacturer stressing the unique advantages of its own approach (Table 1).

Particle-based E-paper uses an electric field to move black and white particles up and down to change the image. The E Ink method of handling black and white particles is probably the best-known of the microcapsule liquid approaches, but the Bridgestone approach, for example, moves the particles up and down in air for an extremely fast response speed of only 0.2ms. Unlike E Ink’s device, which is designed for dot display with active drive, the Bridgestone design offers high-definition dot displays even with a passive drive. Dr Hiroaki Wada, general manager, Dept of High Performance Product Development, Research & Development Div, Bridgestone, pointed out: “We have already prototyped a high-definition E-paper using the cheap and simple passive-drive design, achieving XGA resolution (1,024 x 768 pixels) on a 7.5-inch screen.”

Cholesteric liquid crystal E-paper is stable in both transparent and reflective states, making use of the unique properties of liquid crystal. Fujitsu stacked three cholesteric liquid crystal layers, each selectively reflecting a different wavelength, to prototype a 4,096-color design. The firm’s Hashimoto commented, “We will also develop a 260,000-color model before the end of fiscal 2005.” Asahi Glass’s Satoshi Niiyama, unit leader, Research Center, said, “We have built in a technology to eliminate the ‘burning in’ that can occur with cholesteric liquid crystal.”

The article discusses optically rewritable e-paper, where

new data can be projected onto the paper from the rear to rewrite the displayed image. This is possible because of a unique structure, with a photosensitive layer positioned under the cholesteric liquid crystal film. When irradiated by light from the side opposite the liquid crystal, the resistance of the photosensitive layer changes in proportion to optical intensity. The liquid crystal film, connected in series to the photosensitive layer, changes the displayed image because the voltage input changes in relation to that resistance.

This principle of operation makes it possible to eliminate electrode patterning, for pixels. In fact, the only drive electrode is the single one covering the entire plane. Because of this, explained Fuji Xerox’s Mita, “Our approach is not limited by the drive electrodes, making it a lot easier to drop costs and fabricate larger screen sizes.”

In the future, the firm hopes to make it possible to just press this E-paper against a computer monitor in the office to automatically write the screen image to the E-paper. At present, however, a dedicated writer is required to provide the high optical intensity and directional light beams required.

Color and flexibility of the display are also addressed:

The most aggressive player in this field is E Ink, which displayed a prototype E-paper full of original technology at FPD International 2005, in October 2005. The prototypes included a 4,096-color model made using color filters developed by Toppan Printing Co, Ltd of Japan; a model with improved display performance, such as reflectivity, made with an improved ink which retains brightness even when used with color filters; and a flexible model using thin-film transistors (TFT) on a stainless steel substrate, developed jointly with LG Philips LCD Co, Ltd of Korea and others. At present these characteristics are implemented in independent products, but the firm plans to bring all of the constituent technologies together into one E-paper product in about 2007.

Regarding available technologies for the TFT backplane on a flexible substrate the article states:

Organic TFT and other materials are not expected to be ready for commercial use by around 2007, though, meaning that the firm [E Ink] could lose the business window of opportunity. It identified TFT on stainless steel substrate as a strong candidate; it can be manufactured on the same equipment used to make amorphous Si TFT, leading Kuwada to believe that it “…is the technology for TFT on a flexible substrate likely to be brought to the practical level first.” […]
[There] are a number of competitors for TFT on flexible substrate. Seiko Epson has a proprietary technology to transfer TFT from a glass substrate to a plastic one, using Surface Free Technology by Laser Ablation/Annealing (SUFTLA). The firm is applying SUFTLA in the development of peripheral technologies such as microprocessors and memory, in addition to E-paper (Fig 4).

BusinessWeek has a story on electronic ink applications, such as Hitachi’s electronic paper advertisement displays, updated via wireless connection.
They remind us of the fact that modern information technoloy has not led to the once envisioned paper-free office.

But the fact is, paper hasn’t gone away. The spread of the Internet and the rise of the PC have made information ever more accessible, leading not to the death of paper but to its proliferation. In 2004, worldwide paper production was roughly 400 million tons, compared with about 300 million in 1995, according to Japan Pulp & Paper statistics.

It remains to be seen whether or how soon e-paper will replace real paper. Applications such as rewritable shop price tags and billboards, where e-paper can provide added functionality, compared with traditional paper,

could help the market for e-paper surge to nearly $900 million by 2011, from $2 million last year, according to Tokyo-based market watcher Techno System Research.

The article goes on to mention colour electronic paper and printable OLEDs.
It’s cleary a business article, so we can forgive them for confusing some of the technical details:

Despite their differences, LCDs and OLEDs share two important traits: They can quickly change what they display and don’t need a backlight, so the only time they use power is when text or images change.

Of course LCDs and OLEDs are fast compared to most e-paper types, but, unlike bistable e-paper, constantly require power. Also, most LCDs do need a backlight (or frontlight), at least for low-light situations.

MobileRead compares the specs of the recently announced iRex Iliad (December 2005) and the Sony Reader (January 2006, successor to the Librie):

Dimensions:
Sony: 6.9″ by 4.9″ by .5″
iRex: 6.1″ by 8.5″ by .63″

Weight:
Sony: 8.8 ounces
iRex: 13.7 ounces

Screen:
Sony: 6-inch SVGA 800X600 4 grey scales (same like the Sony Librie)
iRex: 8.1-inch XGA 1024×768 16 grey scales

Internal memory:
Sony: ? “approximately 80 unillustrated books”
iRex: 64MB RAM, 224MB FLASH

Expansion slots:
Sony: SD, Memory Stick
iRex: SD, CF II

Support e-book formats:
Sony: BBeB Book (Sony Librie), Adobe PDF, JPEG, MP3
iRex: Adobe PDF, XHTML, TXT, MP3, others in near future

Others interfaces:
Sony: headphone jack
iRex: headphone jack, WiFi 802.11b, 10/100Mb Ethernet

Price:
Sony: USD $299-$399
iRex: ?

The iRex packs more features into a slightly larger device and supports more formats. Seeing as it has WiFi and can render HTML, I hope they include a web browser. E Ink will be perfectly adequate for mainly text-based pages, such as news sites or webmail. Animations or scrolling are not really essential anyway…

Note: iRex is a Philips spin-out. The first electronic ink ebook reader, the Librie, was a collaboration between Philips, Sony, and E Ink.

___________________________

UPDATE: the iRex Iliad went on sale in June 2006 for EUR 650; the more affordable/basic Sony reader in September 2006 for USD 350.

This USB flash memory drive features an E Ink storage capacity indicator, made possible by the bistability of the display medium.

E Ink and Toppan Printing (supplier of LCD colour filters) have announced a full colour electronic ink display, that

achieves 12-bit color in a 400×300 pixel format with resolution of 83 pixels per inch, using a custom color filter from strategic partner Toppan. The color filter design has a high-brightness layout (RGBW) that preserves the paper-like whiteness of the background page while enabling deep blacks for text and a range of colors and tones for images. A smart algorithm uses color sub-pixels to smooth black and white text, for enhanced legibility equivalent to a printer. The display diagonal is 6 inches, similar to a paperback book in size. […]
Mass production of color electronic paper displays is expected to start at the end of 2006, with future plans for flexible versions.

Fujitsu has presented a flexible colour electronic paper display,

constructed of three displaying layers - red, blue, and green. Since no color filters or polarizing layers are required, it features color that is significantly more vivid than conventional reflective-type LCDs. […]
Fujitsu will conduct test marketing and practical-use testing, targeting commercialization within fiscal 2006 (April 2006 to March 2007) to promote field innovation using its new electronic paper.

According to their website, Fujitsu’s

e-paper is based on highly reflective cholesteric selective reflection technology. Cholesteric refers to the mesomorphic phase of a liquid crystal in which the molecules are aligned in a specific manner, in this case, a spiral configuration. Up to 50% of incident light in specific wavelengths and colors is reflected.

Researchers at the HP Labs in Bristol (UK) have developed a prototype bistable passive matrix LCD display (3cm x 4cm, 128 x 96 x RGB).

The development is targeted at applications such as electronic books and magazines and digital posters and photographs, rather than video displays such as TVs and computer monitors. […]

The bistability of the display is achieved using a special surface structure embossed in the plastic substrate.

In the HP Labs prototype, the ability of the pixel to remember its state is produced by tiny posts less than a thousandth of a millimeter wide, which are imprinted on to the plastic. These posts hold the liquid crystal in one of two orientations, corresponding to ‘on’ and ‘off’.

The display also has electrodes that are integrated with the printed color filters, further simplifying the device. The electrodes and color filters are made by imprinting shapes on to the plastic, and then using the shapes as templates for the color filter and electrode materials. This gives very precise control of features – such as metal lines five microns wide.

“All of the patterning in the prototype has been carried out by printing-like processes,” said Geisow. “The details of the processes are still being developed, and we expect it will take a few more years of further applied research to properly develop and assess their commercial potential.”

Coverage at The Register.

This reviewer of the recently released Sony Librie praises the screen quality (apart from the slow refresh rate), but does not like the digital rights management (DRM) system used:

Sony has opted for a DRM and distribution system for the Librie that must have been designed by the same guy who made up the guidelines for NetMD’s DRM. In other words, some dinosaur in SonyHQ who still doesn’t read his own e-mail since he can’t use a keyboard.

As of launch day, Sony’s new book rental program contains a whopping 400 books. That’s it. The convenience store down the street from my apartment has a wider and more current selection. Also, the innovative (read as idiotic) new 60-day-and-it-evaporates download service has NO periodicals! No magazines, no newspapers. The only types of documents that would lend themselves to a rental system aren’t even offered. Instead we end up with a moldy list of books that would be public domain if it weren’t for the fact that Japan doesn’t believe in giving away information for free, even if no one would want it.

Royal Philips Electronics, Sony Corporation and E Ink Corporation announced today the world’s first consumer application of an electronic paper display module in Sony’s new e-Book reader, LIBRIÉ, scheduled to go on sale in Japan in late April. […]
The Electronic Paper Display is reflective and can be easily read in bright sunlight or dimly lit environments while being able to be seen at virtually any angle - just like paper. Its black and white ink-on-paper look, combined with a resolution in excess of most portable devices at approximately 170 pixels per inch (PPI), gives an appearance similar to that of the most widely read material on the planet - newspaper. Because the display uses power only when an image is changed, a user can read more than 10,000 pages before the four AAA Alkaline batteries need to be replaced. The unique technology also results in a compact and lightweight form factor allowing it to be ideal for highly portable applications. […]
The commercialization of this revolutionary display technology is a result of a strategic collaboration started in 2001 among E Ink Corporation, Toppan Printing and Philips together with Sony. […]
E Ink Corporation supplies electronic ink to their manufacturing partner Toppan Printing, who in turn processes the ink into a thin film called frontplane laminate. Philips integrates E Ink’s frontplane laminate with an active matrix backplane and adds the driving electronics component. Philips works with Sony to co-develop and customize display solutions for innovative mobile devices.