ePaper

E-paper is a display technology designed to resemble ink on paper by using microcapsules containing black and white pigment particles suspended in a fluid. When an electric field is applied, the particles migrate to the surface to form text and images, and the image is bistable, meaning it can remain without power.

Most commonly, e-paper refers to electrophoretic displays (EPD), such as those marketed under the E Ink brand. Other approaches include electrochromic and electrowetting variants. Key advantages are high contrast, wide viewing angles, readability in ambient light, and very low power consumption for static content; drawbacks include slower refresh rates, limited full-color capabilities, and higher production costs compared with some LCDs.

History: Concepts dating to the 1960s–1990s culminated in the commercialization of E Ink Corporation in 1997. The first widely adopted e-readers appeared in the mid-2000s (for example, Sony’s Librie and later the Amazon Kindle in 2007). Subsequent generations introduced improved contrast, thinner form factors, and color-capable e-paper displays through Triton, Kaleido, and Advanced Color ePaper technology.

Applications extend beyond e-readers to electronic signage, public-information displays, retail price tags, and wearables. E-paper is used in libraries, signage for transportation hubs, and some educational devices due to its legibility in bright light and minimal power needs.

Environmental and practical considerations include recycling challenges and manufacturing costs, but the technology remains favored for long-usage displays that require intermittent updates. Ongoing research aims to improve color, refresh rate, flexibility, and integration with sensors and lighting.