Electronic paper, also called e-paper, is a display technology designed to mimic the appearance of ordinary ink on paper. Unlike a conventional flat panel display, which uses a backlight to illuminate its pixels, electronic paper reflects light like ordinary paper and is capable of holding text and images indefinitely without drawing electricity, while allowing the image to be changed later.

To build e-paper, several different technologies exist, some using plastic substrate and electronics so that the display is flexible. E-paper is considered more comfortable to read than conventional displays. This is due to the stable image, which does not need to be refreshed constantly, the wider viewing angle, and the fact that it uses reflected ambient light. While it is lightweight and durable, it still lacks good color reproduction. The contrast ratio in common devices as of 2008 might be described as similar to dirty newspaper, though newly-developed implementations are slightly better.

Applications include e-book readers capable of displaying digital versions of books and e-paper magazines, electronic pricing labels in retail shops, time tables at bus stations electronic billboards, and the mobile phone Motorola FONE F3. Electronic paper should not be confused with digital paper, which is a pad to create handwritten digital documents with a digital pen.

Applications

Several companies are simultaneously developing electronic paper and ink. While the technologies used by each company provide many of the same features, each has its own distinct technological advantages. All electronic paper technologies face the following general challenges:

• A method for encapsulation

• An ink or active material to fill the encapsulation

• Electronics to activate the ink

Electronic ink can be applied to flexible or rigid materials. For flexible displays, the base requires a thin, flexible material tough enough to withstand considerable wear, such as extremely thin plastic. The method of how the inks are encapsulated and then applied to the substrate is what distinguishes each company from others. These processes are complex and are carefully guarded industry secrets. Nevertheless, making electronic paper is less complex and costly than LCDs.

There are many approaches to electronic paper, with many companies developing technology in this area. Other technologies being applied to electronic paper include modifications of liquid crystal displays, electrochromic displays, and the electronic equivalent of an Etch A Sketch at Kyushu University. Advantages of electronic paper includes low power usage (power is only drawn when the display is updated), flexibility and better readability than most displays.

Electronic ink can be printed on any surface, including walls, billboards, product labels and T- shirts. The ink's flexibility would also make it possible to develop rollable displays for electronic devices.

ADVANTAGES OF ELETONIC PAPER:

1.E-paper makes a flexible display that consumes power only when updated. The design is inspired by a regular tourist map where you get good overview, good level of detail, and quick access combined with the advantages of GPS navigation. Store your images from your digital camera on the internal drive and sync them to the GPS log. Now you can see exactly where your photos were taken. Share this information directly by using WiFi or piggyback your phone with Bluetooth.

2.The manufacture of electronic paper promises to be less complicated and less costly than traditional LCD manufacture.

3. . The ideal electronic paper product is a digital book that can typeset itself and could be read as if it were made of regular paper, yet programmed to download and display the text from any book. Another possible use is in the distribution of an electronic version of a daily paper.

DISADVANTAGES OF ELECTRONIC PAPER:

1. Electronic paper technologies have a very low refresh rate comparing with other low-power display technologies, such as LCD.

2. Another limitation is that an imprint of an image may be visible after refreshing parts of the screen. Those imprints are known as "ghost images", and the effect is known as "ghosting".