E-paper is a thin, flexible polymer sheet with the look of paper. But e-paper is a bit thicker than regular paper and weighs more because it contains microscopic electronic ink particles sandwiched between two polymer sheets that display as either white or black in response to an electrical charge.

E-paper is reflective, like real paper, so it can be read in any light. E-paper is also bi-stable, which means that the display uses power only to change the content.

Those two main characteristics are what give a paperlike display its good qualities—it's comfortable to read because it's reflective, and the bi-stable aspect allows you to have low power and lightweight batteries so the whole device could be extremely thin and lightweight.

E Ink and Gyricon both offer e-paper products. The basic technology the vendors use is the same, but each takes a slightly different approach.

E Ink's e-ink consists of millions of microcapsules about the diameter of a human hair. These clear capsules contain a clear fluid, as well as tiny black and white particles. The two colors each carry opposite charges. When an electrical field is applied, the particles move up and down within the capsules. A negative electric field makes the white particles move to the top of the microcapsule, where they are visible to the user. A positive charge pulls the black particles to the bottom of the microcapsules, hiding them. The technology is used for e-paper and can be embedded in electronic displays.

SmartPaper, an e-paper technology from Gyricon LLC, a wholly owned subsidiary of Xerox Corp, consists of two sheets of thin plastic with millions of tiny beads embedded between them. Each bead, smaller than a grain of sand, has a different color on each side. The hemispheres also carry opposite charges. Each bead resides in its own oil-filled cavity within the flexible sheet, and under the influence of a voltage applied to the surface, it rotates to present one side or the other to the viewer. The image stays in place until a new voltage pattern is applied, which erases the previous image and generates a new one.

Several companies are developing commercial applications of e-paper technology. SmartPaper is used in an e-paper pricing-sign system for retail stores. The sign is controlled by software that links it wirelessly to in-store pricing databases. So the price on the sign can be updated instantly. And it's always the same as the price in the point-of-sale database.

Gyricon also offers SmartPaper in a line of dynamic message boards, which it sells to hotels, conference centers and large campuses. The message boards sell for $1,295 each.

In April, E Ink Corp., Royal Philips Electronics and Sony Corp. together launched their first-generation e-ink display in Sony's e-book reader, the Librie, in Japan. The e-book incorporates the e-ink technology used in e-paper into a traditional display.

Fujitsu Laboratories Ltd. is developing a paperlike display that it says could be used with a terminal for reading business documents downloaded from a PC. The paper should be in production by 2006, and Fujitsu is bullish on its prospects. This invention may pave the way to a paperless office and reduce paper consumption.

Although e-paper technology is progressing, there are some downsides. One is that e-paper lacks color. And while e-ink has been incorporated into displays, the bi-stable e-paper technology can't support full-motion video because updating or rewriting a page takes too long.

Today, e-paper is still looking for a killer application. While a few retailers are experimenting with e-paper pricing labels, the technology has yet to catch on. But that could change.

In three to five years, we'll see second-generation technologies will probably have better characteristics, reduce costs and add flexibility to the mix.

時(shí)文選讀

電子紙

電子紙是一張柔軟的聚酯薄片，看上去像紙。但電子紙比普通的紙厚一些，也重一些，因?yàn)樗袏A在兩層聚酯薄片之間的電子墨水微粒，它們根據(jù)被加載的電荷顯示出白或黑。

電子紙像真正的紙那樣也能反光，因而能在任何光線下閱讀。電子紙還是雙穩(wěn)態(tài)的，這意味著此種顯示只在改變內(nèi)容時(shí)耗電。

這兩個(gè)主要的特性使這種像紙一樣的顯示器擁有很好的品質(zhì)——由于它是反光的，所以閱讀起來(lái)很舒服，而它的雙穩(wěn)態(tài)讓你擁有低功率的輕型電池，從而整個(gè)系統(tǒng)可以做得非常薄、非常輕。

E Ink公司和Gyricon公司都提供電子紙產(chǎn)品。兩家供應(yīng)商使用的基礎(chǔ)技術(shù)是相同的，但每家各自采用了稍微不同的方法。

E Ink公司的電子墨水由數(shù)以百萬(wàn)計(jì)直徑為人頭發(fā)那樣的微型膠囊組成。這些清晰透明的膠囊包含了透明液體和細(xì)微的黑白兩種顆粒。這兩種顏色的微粒各自帶有相反的電荷。當(dāng)加上一個(gè)電場(chǎng)時(shí)，這些微粒上下移動(dòng)。負(fù)電場(chǎng)使白色微粒移到膠囊的頂部，用戶(hù)就能看見(jiàn)它們。而正電荷把黑色的微粒拉到膠囊的底部藏起來(lái)。此技術(shù)用于電子紙，能嵌入電子顯示器。

施樂(lè)的全資子公司Gyricon公司的SmartPaper電子紙技術(shù)，由兩層塑料薄片組成，它們之間嵌入了數(shù)以百萬(wàn)計(jì)的細(xì)微珠子。每個(gè)比沙粒還要小的珠子在兩端有不同的顏色。珠子的兩個(gè)半球帶有相反的電荷。這些珠子都裝在柔軟薄片中充滿(mǎn)油的腔體內(nèi)。在加在表面的電壓的作用下，珠子轉(zhuǎn)動(dòng)，不是這個(gè)半球就是另外一個(gè)半球?qū)χ^察者。圖像保持不變，直到新的電壓加載，才擦去以前的圖像，生成新的圖像。

有幾家公司正在開(kāi)發(fā)電子紙技術(shù)的商業(yè)應(yīng)用。SmartPaper用于零售商店的電子紙定價(jià)標(biāo)簽系統(tǒng)。這種標(biāo)簽由軟件控制，通過(guò)無(wú)線與店內(nèi)的定價(jià)數(shù)據(jù)庫(kù)相連。因此，標(biāo)簽上的價(jià)格能即時(shí)更新，而且它始終與銷(xiāo)售點(diǎn)(POS機(jī))數(shù)據(jù)庫(kù)中的價(jià)格相同。

Gyricon公司還在動(dòng)態(tài)信息牌的產(chǎn)品線中提供SmartPaper,該產(chǎn)品賣(mài)給旅館、會(huì)議中心和大型園區(qū)。每個(gè)信息牌賣(mài)1295美元。

(2004年)4月，E Ink公司、皇家飛利浦電子公司和索尼公司聯(lián)合推出了用于索尼的電子書(shū)閱讀器的第一代電子墨水顯示器。該電子書(shū)將用于電子紙的電子墨水技術(shù)引進(jìn)傳統(tǒng)的顯示器。

富士通公司正在開(kāi)發(fā)像紙一樣的顯示器，該公司稱(chēng)，它將用于終端，供閱讀從PC機(jī)下載的商業(yè)文檔。這種“紙”將在2006年投產(chǎn)，富士通公司看好其前景。此項(xiàng)發(fā)明可能為無(wú)紙辦公和減少紙的消耗鋪平道路。

雖然電子紙技術(shù)在不斷進(jìn)步，但它也有不足之處。其中一個(gè)就是電子紙缺少顏色。雖然電子墨水已經(jīng)進(jìn)入顯示器，但雙穩(wěn)態(tài)電子紙技術(shù)不支持全動(dòng)感視頻，因?yàn)楦禄蛑貙?xiě)一頁(yè)的時(shí)間太長(zhǎng)。

今天，電子紙仍在尋找殺手級(jí)應(yīng)用。雖然有些零售商正在試驗(yàn)電子紙定價(jià)標(biāo)簽，但此技術(shù)還需抓住機(jī)會(huì)。情況可能會(huì)有變化的。

在今后的三至五年中，我們將看到第二代技術(shù)可能有更好的性能、更低的成本以及更靈活。