16-10-2010, 02:22 PM
for more details, please visit
http://doc.ic.ac.uk/~frk/frank/da/hci/tu...0paper.pdf
It is a term that has been used rather loosely for a long time, but broadly speaking it is a display technology that has all the attributes of paper but can be written to and erased electronically. We can list some of these basic attributes as follows:
• High resolution (150dpi or better).
• High contrast, equal to that of print on paper (about 10:1 or better).
• Readable in any ambient light conditions
• Readable at any viewing angle
• Excellent ergonomic features, easy to hold, carry, and use.
• Light weight, at most comparable to an equal sized sheet of card.
• Robust, will withstand being dropped, hit, etc.
• Flexible, or at least bendable.
• Cheap, maybe not as cheap as paper, but easily affordable by everyone.
• Reasonable large area, preferably A4 (298x212mm)
• Bistable, once a display is written it will stay displayed even when power is switched off.
A display that meets all of these attributes can be referred to as an e-paper display suitable for use in an e-publication reader, since it is, in virtually all aspects, an electronic replacement for a sheet of paper. Indeed such display technologies are sometimes referred to as paper replacement technologies.
Flexible, bendable or rigid?
Although a lot of emphasis is placed upon e-paper being either bendable or flexible these are in many ways some of the least important attributes of e-paper. However, what is important about these attributes as opposed to a rigid glass based display like an LCD panel, is that their flexibility makes them much more robust and durable.
A rigid glass substrate LCD display will break if dropped on a hard surface, trodden on, sat upon, etc. A bendable display will probably survive most of those accidents. A bendable display panel can also be made much thinner and lighter than a rigid one since it needs no strong physical support to protect it, and so if it is bent when shoved into a briefcase it will survive.
Because it needs no rigid backing a flexible display panel is thin and light weight, and hence it is both highly portable and ergonomically much easier to use.
