E-paper, or electronic paper display (EPD), is a optoelectronic display technology designed to mimic the appearance of ink on paper. Unlike traditional backlit displays like LCDs or OLEDs, e-paper reflects ambient light, making it highly readable even in direct sunlight. This characteristic, along with its low power consumption, has made e-paper displays popular in devices like e-readers and digital signage. E-paper is bi-stable, meaning that once an image is displayed, it can remain without additional power, contributing to its energy efficiency.

The technology behind e-paper involves tiny capsules filled with charged ink particles. These particles, typically black and white, move within the capsules when an electric field is applied, creating text or images on the display. Full-colour e-paper has also been developed, though it remains more niche due to challenges with colour vibrancy and response times. E-paper’s primary advantage is its long battery life and the ability to hold a static image without draining power, making it ideal for applications where updates are infrequent.

E-paper is expanding beyond e-readers into other applications like digital price tags in retail, low-power smartwatches, and even electronic shelf labels in supermarkets. Its reflective display, which reduces eye strain compared to conventional screens, has spurred interest in using e-paper for portable devices that require prolonged reading or display times. As sustainability becomes a growing concern, e-paper’s low energy consumption and potential for being built into recyclable packaging and signage make it a promising option for eco-friendly display solutions.