Kindle E-ink screens use millions of microscopic capsules to mimic physical ink on paper.

Electronic Paper Displays (EPD) were pioneered by the MIT Media Lab in the 1990s before being commercialized by the E Ink Corporation, founded in 1997. The core technology, known as microencapsulated electrophoretic display, involves millions of tiny capsules about the diameter of a human hair. Each capsule contains positively charged white particles and negatively charged black particles suspended in a clear fluid.When a positive or negative electric field is applied to individual electrodes, the corresponding particles move to the top of the capsule, making that spot appear black or white to the viewer. This process is highly energy-efficient because the particles are 'bistable,' meaning they stay in place without needing a constant power supply. Energy is only consumed during the 'refresh' phase when the particles physically rearrange to form a new page.Because the screen does not require a backlight to be visible, it eliminates the glare and blue light exposure associated with Liquid Crystal Displays (LCD) or Organic Light Emitting Diodes (OLED). This reflective property is why E-ink remains perfectly legible under 100,000 lux of direct sunlight, whereas traditional screens often wash out. Amazon launched the first Kindle using this technology in November 2007, forever changing the digital reading landscape.