E Ink is the creator of electronic ink — the optical component of a film used in Electronic Paper Displays. Although futuristic-sounding, electronic ink is actually a straightforward fusion of existing knowledge of chemistry, physics and electronics to create this new material. It’s so much like paper, it actually utilizes the same pigments used in the printing industry today.
Electronic ink is made up of millions of tiny microcapsules, about the diameter of a human hair. Each microcapsule contains positively charged white particles and negatively charged black particles suspended in a clear fluid. When a positive or negative electric field is applied, corresponding particles move to the top of the microcapsule where they become visible to the user. This makes the surface appear white or black at that spot.
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