發布日期：2022-07-14 點擊率：60
E-Ink Corp和Seiko Epson Corp連手開發推出一款電子紙顯示屏控制器IC,據稱該款IC將使電子紙在交互應用中不再受速度限制,有助于推動電泳顯示屏(也稱“電子紙”)的廣泛應用。
“很多原始設備生產商(OEM)認為有源矩陣電泳顯示屏(電子紙)對觸控筆輸入或下拉菜單輸入的反應速度太慢或顯示速度比不上速度快的打字員,但這些都要歸咎于控制器芯片,”E-Ink市場部主席Sri Peruvemba稱,“Epson公司的工程師們幫助我們設計了一款控制器芯片。有了它,電子紙完全可以用于交互應用。”
這類顯示屏的最大優點是,采用反射光替代背光,使得其可在室內光線及強光下從任何角度都可以看清屏幕內容。而LCD顯示屏在強光下對比度會嚴重下降,且視角也受一定限制。
通過配置這款由Epson生產的控制器,E-Ink稱電子紙幾乎可替代各種場合所用的LCD屏,雖然電子紙只有黑色和白色(或有一定灰階)。今后電子紙可用作電子報紙、電子詞典、電子筆記,臺式計算機以及普通筆記本計算機的外部顯示屏。
電子紙(電泳型顯示屏),通過捕獲置于薄膜內部浮于透明液體中的白色或黑色的微膠囊來工作。白球帶負電,黑球帶正電,將薄膜置于可加電場的基板,就會迫使白球向正極移動,黑球向負極移動,從而使電子紙的各種像素點呈現一定顏色。可采用硬質和軟質基板,其像素密度為100~400點/英寸(dpi)。這一工作原理在E-Ink的電子紙中得到了驗證。
電子紙和液晶顯示屏不同。液晶顯示屏必須每隔15毫微秒將每個象素點刷新一次,而電子紙(電泳顯示屏)沒有這一要求。此外,控制器僅傳送電信號給需要變化的像素點,這樣,對給基板提供電荷的控制器反應速度的要求就相對要低,約250毫秒每像素變化。由E-Ink和Seiko Epson共同開發推出新款加速控制芯片可以同時刷新多達16個像素點的狀態,從而大大提高了電子紙的感知速度,刷新速率可等效LCD屏(約15 ms)。
E-Ink之前所推出的電子紙控制器不能完成多個像素的同時更新,使得電子紙存在明顯的后滯現像,特別是在需要改變整頁紙內容的情況下。E-Ink稱新款芯片可實現設計用于支持實時鍵盤輸入、基于電子筆的手寫輸入和導航菜單和指針的交互用戶界面。
“我們找來我們公司最快的打字員來進行測試,結果沒有人的輸入速度可以快過采用新控制器芯片的電子紙。”Peruvemba稱,“我們試過播放視頻,結果發現采用新控制器芯片的電子紙和LCD效果一樣,但事實上電子紙所用的電泳技術和從前一樣。
E-Ink表示已有多家OEM在開始著手設計基于E-Ink電子紙、采用硬性和柔軟基板的產品。當前最搶眼的設計包括Sony和所推出的電子書。此外,已有包括三星和LG電子在內的6家OEM宣布正著手設計采用電子紙的產品。
新款控制器芯片(Epson產品編碼:S1D13521B)將于下月開始交付OEM生產。此外還將會提供一款標準參考設計模塊---AM300電子紙。AM300由一個完整的5~9.7英寸(對角線長度)的電泳顯示屏、Epson生產的顯示屏控制器、其它必要的驅動電路和用于存儲畫面內容的小型閃卡插槽組成。
翻頁查看英文原文:
Chip gets e-paper up to speed for interactive apps
Electrophoretic "electronic paper" displays will get a speed boost next month as a result of a deal between E Ink Corp. (Cambridge, Mass.) and Seiko Epson Corp. (Tokyo). The companies have jointly developed an electronic-paper display controller that they claim breaks the speed bottleneck that has stood in the way of e-paper's use for interactive applications.
"Many original equipment manufacturers thought that active-matrix electrophoretic displays were too slow for stylus input or drop-down menus??or even to keep up with a fast typist??but the bottleneck was the controller chip," said Sri Peruvemba, vice president of marketing at E Ink. "The engineers at Epson helped us design a controller chip that proves interactive applications are possible for electrophoretic displays."
The main advantage of such displays is that they use reflected light instead of a backlight, making them easy to read at any angle in normal room lighting as well as in bright sunlight. LCDs, by contrast, are hard to read in sunlight and have a limited viewing angle.
With the faster Epson-manufactured controller, E Ink claims that electrophoretic displays can tackle nearly every application now served by LCDs, albeit only in black and white (or a limited number of gray scales). Applications include e-books, newspapers, -notebooks and -dictionaries; tablet PCs; and auxiliary displays for ordinary laptop computers.
Electrophoretic displays work by trapping microcapsules of white and black pigment??electronic ink??inside a thin film, where they float in a transparent liquid. The black microcapsules are negatively charged and the white ones positively charged. By laminating the film onto a substrate that can apply an electrical charge, either the black or the white microcapsules of electronic ink can be forced to the surface at specific pixel locations. Both rigid and flexible substrates, ranging in pixel density from 100 to 400 dots per inch (dpi), have been demonstrated with E Ink's electrophoretic displays.
Unlike a liquid-crystal display, which must refresh each pixel location about every 15 milliseconds, electrophoretic displays do not require a raster scan of the entire display. Rather, the controller only sends an electrical signal to the pixels that need to be changed. Consequently, the controller that supplies the electrical charge to the substrate can operate on a slower time scale, of about 250 milliseconds per pixel change. The new, speedier controller chip jointly developed by E Ink and Seiko Epson can change the state of up to 16 pixels simultaneously, increasing the perceived speed of the display to be on a par with that of LCDs (about 15 ms).
E Ink's previous display controller did not perform parallel pixel updates, making devices noticeably sluggish, especially when changing the state of an entire page. E Ink claims the new chip enables interactive user interfaces to be designed for e-ink displays supporting real-time keyboard entry, stylus-based sketching, and navigational menus and cursors.
"We got the fastest typists we could find in our company to try it out, and none of them could type faster than the new controller," said Peruvemba. "We have also tried displaying video and have gotten a response that looks like an LCD, when in fact it is still using the same electrophoretic technology as before."
E Ink claims dozens of OEMs are readying devices, using both rigid and flexible substrates, based on its electrophoretic displays. The most notable designs to date include e-books from Sony and , but six other OEMs have been announced, including Samsung and LG Electronics. Epson itself is readying devices using E Ink's electrophoretic displays.
The new controller chips (Epson part number S1D13521B) will be made available to OEMs next month. Also available will be a reference design module, called the AM300 Broadsheet, that will include a complete electrophoretic display measuring 5 to 9.7 inches on the diagonal, along with the Epson-manufactured display controller, other necessary drive circuitry and a compact flash card slot to hold the images to be displayed.
