12 THINGS YOU NEED TO KNOW ABOUT EPAPER

As most people are familiar with the use of E Ink material – epaper – in e-readers the professional display market is more and more aware of its advantages. This listy is meant to give a brief update or information of ePaper, how it works and what it is used for in professional environments and products.

1 ) ePaper – this is how it works – is bistable

Eink or epaper displays use bistable technology. The pixels are tiny capsules with negatively charged black particles and white particles that are positively charged. Applying positive charge to the top and negative to the bottom, the black particles are drawn into view and white ones out of sight, creating the dark areas on the display. A negative charge to the top and positive on the bottom enable white areas. Important is that once the particles are in position, they remain there for years, untill changed with a negative or positive charge.

2) ePaper is ideal for low power signage, beating ‘noisy’ TFT LCD

As TFT LCD has to refresh 50 times per second regardless of the change of image. Compare this to ePaper that only uses power when changed, the math is easily done. Although for making best use infrequent updates provide obviously best results.

Designers and architects also like the calmness of the (black and white) epaper displays compared to the ‘light noisy’ LCD. Nice example is the epaper wall or ‘eWall’ in UN’s delegate lounge in New York – designed by Dutch architect Rem Koolhaas – watch the video .

3 ) EInk material is ideal for solar powered, of-the-grid applications, enabling no battery change – even in winter

A current ‘hot’ application of e-paper is the use for realtime passenger information like at busstops. In this way the advantages of epaper are fully used. Solar powered units, maybe fed by GTFS data can be placed anywhere, and when power fails last information will be shown, or even a message.
Issue that needed to be solved though is the change of battery in winter time. MpicoSys managed to develop a solar unit that does require less than 25% of regular battery management systems (BMS). In previous years there were examples of a BMS taking all the power of the solar unit in winter time.

4) EInk material is ideal for no battery products – NFC updated

Due to its low power consumption and its bistability (the image remaind visible) more and more applications with EInk material appear like NFC updated visitor badges, nametags and doorsigns. Nice application is the chair numbering system of Casala in the Netherlands, Zifra .

5) ePaper is like regular paper, what is printed or displayed, remains visible for years.

The bistability of ePaper enables a paperlike experience. It only used power when it changes. So even if you lose a power source, the last image will remain visible.

6) ePaper can display readable barcodes and QR codes like normal paper.

E Ink displays are ideal in fast changing areas like logistics and warehousing, where for years regular paper is used. Now more and more companies tend to investigate the change to ePaper displays. Greener and easier to update. An example is a car manufacturer that changes the A4 picking list with a 13.3” E Ink display.
Which not only saves the walk of 30-50 metres to the printer in the corner, the printer will never run out of paper anymore..

7) e-Paper is way better readable in sunlight than LCD.

The backlight of LCD (enabling the image to be visible) will be impacted by the sun. Something that is not the case with e-paper. In fact epaper will be as readable as regular paper, use in sun is perfect as they are reflective. Sunlight absorbing dark areas and reflecting light areas enable a good visible image.

8) ePaper has a viewing angle than regular paper that can be close to 180°.

The reflectiveness of the E Ink material enables better viewing angles than regular paper, which can be close to 180°. Even if you are not in front of the display the message can be read or image seen properly.

9) E-paper can be updated in below zero temperatures.

Though E Ink warranty for years only covered 0° and 50°C. This has changed, as in 2014 MpicoSys introduced updates upto -15° C. Now E Ink has not only added below zero temperatures to its warranty, but also developed a complete product range for cold environments, aimed at operating in temperatures from –25°C to 10°C. Typical markets for those are ESL, retail freezers signage and IoT devices.

10) Partial updates is possible with ePaper – enabling speedy updates with reduced data sent.

In the early years updating e-paper displays meant refreshing the entire content, like obe experiences with e-readers.
Using partial updates, like MpicoSys uses for fast updating realtime busstop passenger information, enables lower power and lower sized packets of data sent. Not only cheaper (as costs for sending data will be lower) but also faster, enabling multiple updates per minute. Ideal for this specific purpose.
Key in this is the caching of data and sending only little changes.

11) Color is possible with E Ink displays.

Most of the (now) implemented displays are black and white. In the ESL (Electronic Shelf Labeling) market more and more the third color red is used in smaller labels.
E ink already introduced the 31.2” and 42” in full color. E Ink will also introduce products using their Advanced Color ePaper (ACeP) technology in 2019 (see image below).

12) Most ePaper displays are available as development kits and not all sizes on website manufacturer.

Experimenting with ePaper is a good thing to do. Not only display manufacturers enable development kits but also development companies like MpicoSys. E Inks website offers kits, Pervasive as well via http://www.pervasivedisplays.com/kits and Plastic Logic via https://www.plasticlogic.com/products/evaluation-kits/.

Note that some sizes will not be om the manufacturers website, as they have been custom developed for one or more customers. But might be available when used for other purposes than the the use the original development was intended. Like for a sportswatch, luggage tag or digital license plate.