E Ink

Developed by the MIT Media Lab, E Ink technology is proprietary to E Ink Corporation and allows for a new generation of battery-powered portable e-book readers to display text and graphics with a high resolution, while not consuming power to maintain the display. Tiny black particles represent the pixels by their proximity to the surface of the screen. Near the screen, they are seen as a small black dot, much like the screen process for printing black and white photographs. This technology allows portable readers, such as the Hanlin V2 and Sony Portable Reader PRS-500 (Early pioneering products), to consume power only when advancing pages, or zooming in or out.

How it works

E Ink, uses tiny liquid filled bubbles that contain both white and black "ink". Each bubble represents a pixel on the screen display. Electronic charges are applied to the bubble to bring either the white ink or the black ink to the surface. Once the charge is removed the ink will stay at the surface so it can been seen without any power applied. The bubbles are the same size as a pixel on the screen and the connection of all these bubbles can form text characters and images on the surface of the screen. A positive charge will cause white ink to appear while a negative charge will cause black to appear. A charge can be applied to affect a small portion of the bubble instead of the whole bubble. This can be used to cause a mix of white and black (gray) to appear.

Once the electronic ink microcapsules have been created, the ink is laminated onto a sheet of plastic film that can be cut into different shapes and sizes. These cut parts are then affixed to layer of circuitry that can create an electric field across the microcapsule. It is this electric field that causes the ink to move within the microcapsules and switch from white to black. For E Ink's Active Matrix displays, the circuitry is a thin film transistor (TFT) array of dots or pixels that allows for very high resolution images and text.

The E Ink plastic film can be applied onto virtually any surface, including glass, plastic, fabric and even paper. However, the TFT layer is usually on a glass substrate.

Modules

Modules consist of a TFT (thin film transistor), Ink layer and Protective Sheet. In addition, product designers can include a touch solution, which is incorporated into the module stack. E Ink currently offers digitizer and capacitive touch solutions. Digitizer touch technology utilizes a stylus to update the display, with the touch sensor sitting under the TFT. Capacitive touch technology utilizes finger swipes, and is placed on top of the display module. E Ink's touch solutions will not affect the reflectivity of the display. The touchscreen layer can utilize glass or flexible plastic surface.

A Module can also include a frontlight layer. The frontlight page shows a diagram of how the layers are stacked. The larger screen displays do not offer a frontlight option.

For more information

• E Ink display specifications - covers the Vizplex display with 7:1 contrast
• E-paper general technology
• E Ink Pearl main stream display with 10:1 contrast replaced the Vizplex
• E Ink Triton Color E Ink technology and E Ink color
• E Ink Mobius large screen flexible display. Works with either Pearl or Carta screens
• E Ink Fina thin lightweight
• Front light E Ink screen lighting
• E Ink Carta offers 50% more contrast 15:1
• E Ink Spectra A three Ink system
• PocketBook CAD Reader shows off the new E Ink Fina display.

Available e-book products

Currently available products that incorporate E Ink High Resolution Displays include:

• Amazon's Kindle, Wireless Reading Device and the Kindle DX
• Amazon's Kindle paperwhite 2 display uses the latest Carta screen technology.
• ARINC's eFlyBook, General Aviation eReader
• BeBook's BeBook
• Bookeeen's CyBook Gen3
• Emano Tec's Medtab 100
• iRex Technologies' iLiad and Digital Reader
• Jinke's Hanlin V Series eReader
• Polymervision's Readius
• Sony's Personal Reader (PRS-505) and the Personal Reader (PRS-700)
• NeRD - Naval reading device for submarines.

Other E Ink-display based products (non necessarily "High Resolution") can be found at EBook Reader Matrix.

Samsung Electronics achieved a world's first at the SID event with a largest-ever high resolution E Ink Vizplex imaging film at 40" diagonal - the size of a large flat-screen TV, which consumes very little power: 300mW at one frame per minute, or 1/500 that of a conventional LCD display. Such a display using electronic ink would be appropriate for digital signage and office information applications.

Available products (other than e-book readers)

Currently available products featuring E Ink Segmented Displays include:

• ART Technologies, Ltd., Phosphor Innovation Electronic Ink Watch
• Lexar's Jumpdrive Mercury and Secure Plus II USB memory sticks
• Funkwerk Information Technologies Karlsfeld GmbH's Pariflex DRFID (bar code Display on a RFID tag) Smartlabel
• Motorola's MOTOFONE F3, GSM Mobile Phone
• Seiko G300, Ladies Electronic Ink Fashion Watch
• Earl is a GPS and survival camping product that could also serve as an eBook Reader and even a Tablet.
• InkCase is a case for a Smartphone that includes a display on the back.
• Visionect V Tablet is a 6" Wi-Fi enabled waterproof Tablet that runs web-based applications. Platform is open to everybody.

Available development kits

Currently available development tools:

• E Ink AM200 Prototyping Kit in 5", 6", 8", 9.7" panel sizes
• Seiko-Epson, Segmented Display EPD Evaluation Board
• Prime View International, High Resolution Prototype Development Kits
• http://www.pervasivedisplays.com/ Pervasive displays sells I Ink displays with available controllers for designing you own device. 1.44" to 10.2" displays available.

Roadmap

During the Society of Information Display (SID) 2007 E Ink demonstrated their latest advances in e-paper.

"Our research team is demonstrating here an ultra-bright ink that is approaching 50 percent reflectance of ambient light compared to 35 percent in shipping monochrome products," said Dr. Michael McCreary, vice president of Research and Advanced Development at E Ink. "Moreover, the advanced ink is capable of high switching speeds. We have put it all together and today we are unveiling our first-ever color research prototype that can play smooth color video."

The increased contrast screen, 10:1, is now available using the name "E Ink Pearl" to describe the display. More recently E Ink Carta achieves 15:1 or better contrast ratio.

E Ink has a color video prototype with a 6-inch diagonal display with 300x400 resolution and RGBW sub-pixels that is capable of switching at up to 30 frames per second. It is expected that the video switching capability may require several years to reach the market, however the color technology is available now.

E Ink displays can also be in applications with little or no light through the integration of a front light solution. A front light use a very thin light guide material to uniformly disperse light over the entire display. The light source is usually in the form of LEDs mounted in the sides of the display module. E Ink can manufacture the entire display module including the front light.