Are you looking for a portable device for reading books, magazines, or the daily news? When it comes to reading, there are two leading display technologies: ePaper and LCDs. LCDs are typically found on smartphones and tablets, while ePaper or e-ink displays are often used on e-readers and ePaper tablets. Although both displays are perfectly capable of producing clear text and graphics, their mechanism of displaying such imagery are very different and will impact the way you read.
What Is LCD?
LCD is a flat-panel display commonly used in small and large displays such as smartwatches, smartphones, tablets, computer monitors, and televisions.
LCD panels are often favored for their high refresh rates, great color reproduction, fair power efficiency, and excellent performance in low-light environments.
Modern smartphone/tablet displays such as AMOLED and LTPO enhance LCD capabilities by adding extra filters and full-array LEDs, resulting in higher refresh rates, better color accuracy, wide viewing angles, and pixel-level dimming.
How LCD Works
LCD is a blanket term for displays using liquid crystal display technology. In its most basic form, an LCD panel comprises a backlight, a vertical and horizontal polarizer, a color filter, and a liquid crystal display.
At the very back of the panel is a backlight. The backlight provides the necessary amount of photons/light, which can be manipulated to produce all the shapes and colors you see on the display.
To shape the light, an LCD is placed in front of the backlight. The LCD is composed of two polarizing films that encase a liquid crystal panel. By electrically controlling the liquid crystal panel, photons can be adjusted to align with either the horizontal or the vertical polarizer, forming an image.
What Is ePaper?
Electronic Paper (ePaper) is a type of display that mimics paper. As such, ePaper is often the preferred display for e-readers like the Amazon Kindle, Kobo Nia, and Onyx Boox. They are also known to be used in digital signages, tablets, note-taking devices, and wearable technology.
Unlike LCD, ePaper doesn’t have a backlight. Instead, ePaper uses its transparent display to bounce ambient light on the screen, illuminating text and graphics like how actual paper behaves. This dramatically reduces glare, provides excellent viewing angles, and makes reading much less straining on the eyes.
Also, ePaper panels do not require power to maintain the displayed text and images. The only time ePaper uses power is when it partially or fully refreshes the screen to change the imagery being displayed. This makes e-readers very power efficient, often lasting 2-6 weeks (depending on usage) on a single charge.
If you’re looking to read comics and other colored media, getting an e-ink tablet instead of an e-reader might be the better device for you. These tablets use ePaper panels that display colors and are usually paired with electromagnetic resonance (EMR) layers, allowing you to use a stylus for writing notes and drawing.
How ePaper Works
In its simplest form, ePaper displays make use of a thin film of micro-capsules backed by an electrode panel. Each micro-capsule is as light as a human hair and houses millions of electrically charged ink particles suspended on clear fluid.
When the electrode applies a positive charge, all the negatively charged ink particle in the micro-capsule get attracted toward the bottom and causes the positively charged ink particles to surface. In contrast, applying a negative charge on the microcapsule will cause the positively charged ink particles to move to the bottom and let the negatively charged ink to surface.
Many ePapers also have the capability to display half-black and half-white dots by applying both positive and negative charges on the same microcapsule. This makes the ePaper provide more precise details, which is always a plus when it comes to reading.
What’s Better for Reading?
Both LCDs and ePaper panels are perfectly capable reading displays. However, specifically for reading purposes, ePaper is arguably the better panel. But why?
When it comes to more general-purpose devices like smartphones and tablets, LCDs are the best choice. It provides beautiful images, doesn’t flicker when changing graphics, and is generally more inexpensive to produce. However, for a reading device, most LCD features do not necessarily translate to a better reading experience.
In contrast, most features on an ePaper display make reading much more enjoyable. With an ePaper display, readers won’t have to worry about glare, eye strain, and battery life. Furthermore, e-readers equipped with ePaper often have higher water resistance than LCD, making them the better option when reading near the pool, by the beach, and during fishing trips.