Introduction - What is E Ink and E-Paper?
Electronic paper (or e-paper) is a collective name for display technologies that resembles real paper - in terms of display clarity (contrast), sunlight readability, thickness and flexibility. The most popular e-readers (such as Amazon's Kindle) use E Ink display for example.
While it's possible to fabricate flexible e-paper displays, such displays aren't available on the market today as companies are still perfecting the technology and developing ways to actually commercialize it.
The term e-paper is quite confusing, as actually there are several different technologies trying to achieve the same goal: a flexible, thin, sunlight-readable efficient paper-like display. Here is a list of the leading technologies around:
There are also some other technologies, which offers low-power reflective displays. While these aren't really e-paper technologies, they do compete with e-paper displays for sunlight readability and power consumption:
E Ink is currently the clear leader in e-paper displays. E Ink screens are made by E Ink Inc and are used by Amazon, Sony, Samsung, Barnes & Noble and others in their e-readers and other products.
E Ink displays are Electrophoretic (a science which was actually discovered back in 1807 and deals with particle motion as influenced by electric field): they are made of tiny capsules (0.04mm in diameter) that contain two kinds of particles: black and white. Using electricity you can choose whether the white or black particles will rise to the top of the capsule - and so change the color of the pixel. Those particles remain in place when no electricity is used - and so the displays do not need power when the image does not change. E Ink also offers color e-paper which uses color filters on top of the black and white display (these aren't available commercially yet).
Where can I find e-paper displays?
The most popular application for e-paper displays today is an e-reader. Popular readers include Amazon's Kindle, Sony Readers and the Barnes & Noble Nook. Those e-readers feature great sunlight readability and long battery life (a few weeks usually) - all thanks to the E Ink display.
Other products include mobile phones (for example the Motorola Motofone which uses an E Ink as the main display and Samsung's Zeal which uses small E Ink displays on the keyboard), wrist watches, hard-disks and more.