eInk

E Ink, or electronic ink, refers to electrophoretic display technology developed for portable devices and now produced by E Ink Holdings. The display consists of tiny microcapsules embedded in a thin film between two substrates. Each capsule contains white and black pigment particles, and sometimes color particles, suspended in a clear fluid. When a voltage is applied to electrodes, the particles migrate to the surface to form text and imagery. The display is bistable, meaning it can retain a static image without continuous power.

E Ink displays are reflective and designed for outdoor readability, relying on ambient light rather than a backlight. They offer wide viewing angles, high contrast in daylight, and low eye strain. Updates to the display are relatively slow compared with LCDs, which can limit video or fast animation. Color capability exists through additional layers or filters, such as Kaleido or ACeP, but full-color performance remains less vivid than LCD or OLED.

Origins and manufacturing: The technology was developed in the 1990s and early 2000s and commercialized as E Ink Corporation. In 2009, Prime View International acquired E Ink and renamed it E Ink Holdings, expanding production and global sales. Over the years, the company has released display generations such as Pearl and Carta (with improved contrast and resolution), as well as color options like Kaleido and ACeP, and flexible formats for curved or foldable surfaces.

Applications include consumer e-readers such as Kindle and Kobo, electronic shelf labels, signage, and some wearables. Advantages include very low power consumption, bistable image retention, and readability in bright light. Limitations involve slower refresh rates, less saturated color, and the need for external lighting in some contexts. Ongoing research aims to improve refresh speed, color gamut, and flexibility to broaden use in mobile and embedded devices.