E Ink is a display technology used by many standalone e-reader manufacturers. We have an article here that explains exactly what E Ink is, who developed it and the technical details behind how the technology works, but these are the bullet points in terms of why it has been the display technology of choice for e-reader many manufacturers:
- E Ink displays are bi-stable, which means that they require no power to maintain a text display. This is a huge advantage for e- readers because battery power is used only when the user turns a page or navigates (as opposed to a backlit LCD display which consumes power the entire time the device is turned on, regardless of whether images are static or not). Many E Ink equipped e-readers allow you to choose a photo or image to display on the screen when the device is sleeping.
- Devices using E Ink displays have much lower power consumption and tend to offer battery life measured in weeks, compared to hours for e-readers equipped with backlit LCD displays.
- Text on E Ink displays tends to be more crisp than on LCD displays.
- E Ink displays reflect light in a manner similar to real paper, so E Ink displays are not only readable outdoors, they often look even better under sunlight (unlike LCDs that are prone to glare, become washed out and are basically unusable in direct sunlight).
- E Ink displays have no viewing angle issues. An LCD display will offer varying quality of view depending on the angle it's viewed at, while you can hold an E Ink display at any angle without any degradation -just like printed paper.
- Backlit LCD displays can cause eye fatigue and reading them in bed has been linked to sleep issues; since E Ink displays are not illuminated, there is no adjustment to display brightness, with no resulting eye fatigue or sleep issues.
What is E Ink Pearl?
Officially announced in July, 2010, E Ink Pearl is the second generation of E Ink technology displays. It has been incorporated into the current generation of leading e-readers, including the Kindle lineup (the Kindle DX was the first e-reader released with a new E Ink Pearl display), the Sony Reader Touch (PRS-650), Reader Pocket (PRS-350) and Reader Daily Edition (PRS-950SC). Several of the more popular e-readers available today including the Kobo Wireless and Barnes & Noble's NOOK have not yet adopted E Ink's Pearl technology. As befits the second generation of a product, E Ink Pearl is not a re-invention of the technology, but a represents a series of improvements that make for a better user experience. The primary advantages of E ink Pearl, as compared to the first generation E Ink displays are:
- Increased contrast ratio (now at 10:1), making the contrast of an E Ink Pearl display (in other words, the way text stands out against the background) even more book-like.
- Standard 16 levels of gray.
- Improved page refresh speed from just under a second with original E Ink technology to 120 milliseconds.
- Lower power consumption.
- E Ink Pearl includes support for localized animation (a feature which comes into play more with e-textbooks than typical e-books).
For those who might be interested in learning more, the full technical specification is here.
For someone looking to buy an e-reader that uses E Ink technology, the difference between a model that uses a first generation E Ink display and one that uses a newer E Ink Pearl display boils to a slightly better user experience with the latest technology. Depending on your sensitivity to nuances, the difference may not amount to much. But in general, you can expect an e-reader equipped with an E Ink Pearl display to provide text that looks crisper and blacker with a background that's slightly closer to white and page turns that are significantly faster. If you're on the fence as to whether this newer technology is a must have, your best bet is to try out different e-readers in a store so you can see the difference for yourself.