Active matrix electronic ink comes to life

E Ink Corporation has demonstrated what it claims is the world’s first active matrix electronic ink display capable of producing high-resolution illustrations and text.

The display prototype is 12.1 inches diagonally with the resolution of a typical laptop computer monitor and is capable of creating high quality images, including illustrations. To make the electronic ink easily compatible with the necessary electronics, E Ink scientists developed a new version of electronic ink that changes ten times faster than the previous version.

Contrast was also improved by switching the ink from blue to deep black. IBM Research provided some of the electronics used in their laptop displays to E Ink for the research prototype. Starting with the active matrix from IBM, E Ink engineers added the electronic ink and modified the circuitry to complete a working device.

This new display provides three main benefits over traditional and emerging display technologies such as liquid crystal displays (LCDs), cathode ray tubes (CRTs), light emitting displays (LEDs) and organic light emitting diodes (OLEDs):

Because electronic ink contains the same colouring agents as ink on paper, the display demonstrated by E Ink is three to six times brighter than reflective liquid crystal displays (LCDs), exceeds newspapers in contrast ratio and is easily read in both dim light and full sunlight. Like paper, the E Ink display has a clear image that can be seen at any angle without a change in contrast. In addition, special properties of the ink enable smoother text characters than many displays used today.

Electronic ink allows a fixed image to remain on the screen even after the power source is shut off, leading to longer battery life. The bright paper-white background of electronic ink also eliminates the need for a backlight in most applications. For example, E Ink’s display draws less than 1/1000th the power required by a standard notebook computer screen when used for normal reading. Portable devices incorporating E Ink displays could have far smaller batteries making them less expensive and more portable.

Electronic ink displays are 30 percent thinner and lighter than traditional LCD displays. Because electronic ink displays read like ink on paper, they should cause less eyestrain than most other displays that typically emit or transmit light.

IBM and E Ink will jointly deliver a paper describing the display prototype at the Society for Information Display Conference in San Jose, California in June 2001.

On the web