CHINA– For several years reading in digital form already far exceeded the reading on paper: newspapers, information, news and news items. Recently, Guangzhou OED Technologies, a Chinese company, has specialized in manufacturing electronic paper.

What is electronic paper? 

The electronic paper is flexible support on a display technique that mimics the appearance of an ordinary sheet of paper and do not require energy to leave a text or a displayed image. Unlike conventional display techniques that require a backlight, electronic paper reflects ambient light in the same manner as the usual paper.

How it works ? 

Several technologies can realize electronic paper, two main: electrophoresis and liquid crystal bistable. The electrophoresis technique, which we are only concerned in this article is based on the principle of ion displacement under the effect of an electric field induced by the potential difference between two electrodes. Cations, positively charged, moving toward the cathode while anions, negatively charged, moving toward the anode. Using this technique, microcapsules of the size of a hair are filled with white particles and positively charged black negatively charged particles and then applying an electric field, the particles move towards the respective ends of the capsule that attract. By having million capsules on a surface and using electric fields may generate an image in two colors. This system has the advantage of being very energy efficient (consumes only when changing page and remains as such without energy consumption) and to have flexible screens.  It is even possible to obtain a full-color electronic paper by applying an overlay of colored optical filters on monochrome electronic paper.

Where do we use it? 

Electronic paper is used in a wide range of areas: digital books, electronic labeling, signage, smartphones and now it invites even in the fashion world including Sony planning to work on a watch made with this material.