The writing is on the wall: Digital paper is on the way to becoming a reality in public displays.
Originally conceived as the next step in the evolution of portable information in the age-old tradition of rolled scrolls and bound books, digital paper is now moving into the realm of signage. Real-world uses of digital paper, which is sometimes referred to as “digital ink,” are only now starting to trickle in, but the future of this quickly maturing technology already looks bright to architects and other professionals involved in the design of public spaces.
“For informational display in commercial and institutional environments, its potential is phenomenal,” says David Gales, principal at Vantage Technology Consulting Group (www.vantagetcg.com), an architectural design support consulting firm. “We do a lot of work in the academic marketplace - colleges and universities - and if you start to think about having this kind of technology for presenting information in conjunction with motion video display, it’s pretty amazing. It could be used as an artistic medium, signage, entertainment, general information display, environmental graphics, decorative applications, and for retail merchandising.
As for a timeline, Gales says: “It’s still quite a few years off on a regular basis, to the point of seeing it in our environment to the extent that we see plasma screens today, for example. We use this phrase: ‘Technology isn’t revolutionary. It’s evolutionary.’ By the time we see a particular technology at work in these environments it has to be reliable, the production yields have to be sufficiently high to generate cost efficiencies, and certain standards associated with processing the signal side of things have to evolve.”
Although the concepts behind it can be traced to the early 1970s, digital paper really only started making waves in the last few years when the first applications started showing up as e-books - electronic tablets that can be read like books, but whose content can be swapped in and out by the user. As e-book technology continues to search for a market, companies like E-Ink (www.eink.com) and Gyricon L.L.C. (www.gyriconmedia.com) are making public displays a big part of their push.
Meanwhile, architects, system integrators, and design consultants are eager to get a handle on what digital paper is and how it works.
“There is an emerging area of technologies loosely being grouped as electronic displays, and the definition of what allows something to be called an electronic paper display is somewhat subjective,” says Darren Bischoff, senior marketing manager at
E-Ink Corp. “The quick definition of electronic paper display has three main attributes: 1) easy to read, 2) ultra low-power, necessitating power only when it needs to change an image - not to display it, and 3) thin, light, and ideally flexible. So ultimately, electronic paper is something that looks like paper visually, but also has the feel of paper, and in the future can be rolled or even folded.”
While the term “digital paper” is starting to emerge as the everyday moniker, the heart of the system lies in a substance that has much in common with ink.
“We look at electronic ink as the core of what we do,” Bischoff says, “creating a liquid that’s made of many of the same materials that many high-quality inks and toners are made out of. But ultimately I think it’s easier for people to understand from the electronic or digital paper perspective. So in the display world, there’s a new category of displays which is starting to be called ‘electronic paper displays,’ or EPD, as opposed to LCD.”
Gyricon LLC’s presence in public displays is dominated by its SyncroSign Message Board, a dynamic information display marketed for corporate, educational, hospitality, and government applications. Gyricon calls its solution eSignage. The product can be network-controlled via a standard 802.11 WiFi interface or over a wired Ethernet port, using the company’s proprietary SignSync software to schedule and manage dynamic sign content. Another Gyricon product, the SyncroSign Merchandiser FreeStyle, targets Point-of-Sale (POS) integration for retail environments.
Technical details differ from manufacturer to manufacturer, but the basic operating principles of digital paper are similar. Electronic ink starts as a proprietary material that is processed, through a fusion of chemistry, physics, and electronics, into a film that can be integrated into electronic displays. The principal components of electronic ink are millions of tiny microcapsules, about the diameter of a human hair.
“Encapsulation is a pretty well-defined field that’s used in many industries, from pharmaceuticals to paint,” says Bischoff. “Remember Scratch ’n’ Sniff, for example, which encapsulates something and then, when you scratch, you break the capsule? Pharmaceutical time-release capsules are another example. But we don’t want our capsule to break. It’s almost a miniature display in a system, and it’s our ability to control what goes on in that capsule that allows us to achieve really high resolution.”
Each microcapsule contains positively charged white particles and negatively charged black particles suspended in a clear fluid. Apply a negative electric field, and the white particles move to the top of the microcapsule where they become visible to the user, which makes the surface appear white at that spot. Meanwhile, an opposite electric field pulls the black particles to the bottom of the microcapsules where they are hidden. Reverse the process, and the black particles appear at the top of the capsule, which now makes the surface appear dark at that spot. In aggregate, the capsules are basically like a liquid that then gets applied to a sheet of plastic to create an imaging film. The film is laminated and connected to the electronics that control it.
“In lay terms, this is called a back plane, or a rear electrode,” Bischoff says. “When you make a display you have a top electrode and a back electrode, which allows an electrical field. By making that field, we can move the particles in our capsule up and down to create a display.”
As digital paper progresses, architects will have at their disposal a display that can be programmed to change content once every second, once a minute, or once a day, while drawing relatively low battery power. The lack of a need for electrical wiring or, in the case of the WiFi version, a control cable invites innovative implementations, as does digital paper’s thin and potentially flexible form factor.
“Architects could implement this anywhere that you would use a fabric,” says Phil Crompton, principal at Vantage. “You can put it on a surface without impacting the surface. Plasma screens are 4 inches thick, while this is about a quarter of an inch. In addition, practically every other digital signage technology, like plasma and LCD, is fixed and static; you can’t change that surface once it’s built. You could in theory build a cylindrical (plasma) screen, but you couldn’t change that into a cone, whereas with digital paper you can. It also can be used for shading, since just like fabric, you can put it up there and it blocks the sun. We’ve talked with Rice University about using digital paper as shading in an outdoor area for their cafeteria, running it around as a ticker providing information.”
Digital paper signage also has interesting possibilities for working in conjunction with or even replacing audio-based PA systems, although to Crompton, it’s just one of many options that fit into future plans.
“We’re trying to get rid of audio PA’s because of noise pollution,” Crompton says. “Typically, public address is aimed at a few people in a space, but it’s all or nothing. In hospitals, for instance, everyone has to hear an announcement meant for one family. The problem is you need to attract people to it, so we’re finding better technologies to supplement public address, such as digital phones or tracking systems, almost like restaurant paging.”
As with most budding technologies, it’s still too early to say what the budget impact will be for specifying digital paper displays.
“On the active matrix side, for high-resolution displays on hand-held devices, the price story there is that it costs about the same price as any active matrix display of similar specs,” Bischoff says. “But when you start to talk about signs, there’s really not as clear of a picture. There are lots of different technologies right now, and the total system cost or operating cost needs to be looked at. Whether it’s saving power, maintenance, or installation costs, the advantages make it compelling taken all at once, but it’s not clear on a direct comparison.”
Digital paper is continuing to progress, and once it clears a few more hurdles, it could very well evolve into a solution that makes sense in many places.
“For the mainstream, people will expect the same HD quality as a plasma screen,” Crompton predicts. “If it can’t get there, that will make it just a niche technology. The key is coming up with a product that’s reliable, color as well as the current black and white, good resolution, and relatively price competitive. If they hit those four things - and they should - I think it’s an exciting technology that will take very quickly.”
David Weiss is a New York-based journalist who specializes in writing about entertainment technologies. He can be reached at (firstname.lastname@example.org).