iot: Explained: What is electronic paper display technology and how can it enhance IoT applications

Electronic display technology or ePaper displays can imitate the appearance of paper on a device’s display. EPDs or ePaper displays were made popular by Amazon Kindle. The bi-stable nature of this display technology allows it to be used in devices that don’t have the power budget of a traditional LCD. Recently, there were reports about Apple planning to use EPD technology in foldable iPhones and iPads. Here we will discuss how EPDs work and how these displays can help in enhancing IoT applications.
How do EPDs work?
ePaper displays or EPDs are equipped with tiny capsules filled with charged ink particles that use the same inks as the traditional printing industry. EPDs create highly detailed images with the contrast ratio and readability of printed material when the proper charge is applied.
How are EPDs different from traditional LCDs?
As discussed above, these displays have a bi-stable nature. A bi-stable display, also known as the zero power display, has a unique property that allows an image placed on the display to stay indefinitely without refreshing. However, screen refreshing is essential in traditional LCDs — both active matrix display like TFT LCD and passive matrix display like monochrome character LCDs. EPDs consume power only when the screen is refreshed whereas reflective LCDs continue consuming power to keep the image on the screen.
How can EPDs help in the advancement of IoT?
EPDs can function with extremely low power input, thanks to the bi-stable property of the display. These displays don’t need extra power to maintain the image displayed once the text and images of an EPD have been rendered. ePaper displays operate on such low power that the extra energy can be harvested to make updates. This extra energy enables the use of RFID or NFC devices with the batteryless EPDs.
EPDs can be used to enhance many IoT applications including — logistics, manufacturing and retail. Manufacturers can add these thin, light, highly-readable ePaper displays to extremely power-constrained devices.
EPDs can be wirelessly connected to electronic shelf labels in retail locations. This will allow remote or central management to adjust the prices for dynamic pricing strategies.
ePapers can also improve logistics and manufacturing applications of IoT devices as it offers at-a-glance visibility into RFID/NFC tag data.
Moreover, EPDs can also improve the usability of several battery-powered IoT devices like — utility meters, cold-chain temperature data loggers and environmental sensors.
Other advantages of using EPDs
Some of the advantages of using ePaper displays like — ultra-low power consumption, bi-stable property and NFC/RFID energy-harvesting capability have already been mentioned above. Apart from this, EPDs also serve other purposes. These displays offer high readability even outdoors which makes it an apt display technology for eBook purposes. EPDs can also be used in devices that have a thin and lightweight form factor, which is one of the reasons why Apple might use these displays on foldable iPhones and iPads. Moreover, ePaper displays are available in three colours for manufacturers to experiment with their device display.