E Ink

E Ink

(E Ink Corporation, Cambridge, MA, www.eink.com) Founded in 1997, E Ink makes electronic paper display (EPD) subsystems for handheld devices using E Ink Vizplex Imaging Film. Initially only monochrome, color E Ink displays were introduced in 2010. Products include seven-segment display film for smart cards, shelf labels and the like and partially complete substrates for e-books.

Long Battery Life, High Resolution and Flexible
EPD screens can run up to 30 times longer than LCD screens without recharging. Unlike LCDs, which need constant refreshing, once an EPD display is rewritten, it holds its content indefinitely.

The resolution of EPD devices in production is 167 dpi, compared to 96-120 dpi on LCD screens. Since EPD supports up to 400 dpi, the resolution limitation is in the device electronics.

Microcapsules Filled with Fluid and Particles
The E Ink Vizplex film is made of microcapsules filled with fluid and many charged black and white particles composed of ink pigments. The microcapsules are coated on the film and laminated to the top electrode. Row and column drivers are attached, and the module is shipped to customers who add the bottom electrode. Sandwiched between the electrodes, the black and white particles are drawn to the viewing surface when the opposite charge is applied.

The EPD technology stems from the early 1990s when Dr. Joseph Jacobson of MIT Media Labs improved upon an earlier approach from Xerox PARC that used larger beads and more power. E Ink Corporation was founded to refine the MIT technology. See electronic paper and electrophoresis.

Opposites Attract
The charged particles are attracted to the opposite charge on the electrodes, drawing them to the appropriate side. Up to 16 shades of gray are produced by switching the field with varying durations at the pixel location, causing the black and white particles to mix.

In Bright Light
Unlike LCD displays, such as in the smartphone on the left, E Ink screens are readable on a bright sunlit day at the beach.

How Can It Tell You It's Empty?
Because the last drop of power in this E Ink-based Kindle reader was used to display this screen, and once the pixels were changed, no more power was required to keep it current.

Animated Magazine Cover
In 2008, Esquire's 75th Anniversary limited edition was printed with an animated E Ink cover.

As Sharp as Paper
In 2008, Epson demonstrated a super-high-resolution E Ink prototype. At 385 pixels per inch (ppi), this 13.4" display provided an outstanding 3104x4128 resolution. (Image courtesy of Seiko Epson Corporation.)