Fast update /refresh – The Best E-ink Displays for Industry & IoT

Fast Update

Enhancing the user experience of e-paper with fast update

Using fast (or partial updates) with e-paper displays can greatly enhance the user experience. These updates reduce the time required to update a display, opening up new application areas to designers. In particular, fast updates are particularly beneficial for applications where only a small part of the display needs to change regularly.

Pervasive Displays supports both Normal Update (also referred to as global update or global refresh) and Fast Update (also referred to as local update or fast refresh). A normal update affects every pixel on the display, whereas a fast update only affects the pixels that need to change in order to display the new image. With a fast update, the full image is sent to the driver IC, which compares the image data. A partial update requires an area (window) to be defined, after which the system sends only the image data specific to that area, using the same driving waveform to carry out the update.

Per our experience, the Fast Update provides the better optical quality than Partial Update which is also our highly recommendation.

The benefits of
fast update mode

IoT or industrial devices
Infotainment system, smart appliances, digital signage.
 Human machine interfaces (HMIs).
Spotlight items, alerting devices, shelf talkers
Heating, ventilation, and air conditioning (HVAC)
Touchscreen interactive devices
Meters, loggers, sensors

Fast and Partial update example

Please note that we have currently suspended support for the Partial Update feature in all model sizes. This is due to the ghosting effects are more pronounced with the Partial Update than with the Fast Update, which cannot currently be guaranteed to be absent in any EPD batch production. When performing a Partial Update, the unchanged pixels persist in an unbalanced charge state, resulting in poor optical output quality and may also shorten the display’s lifespan.

Update comparison of fast and partial update

Update type	Global Update	Fast Update	Partial Update
Initialization	Panel initialization	Panel initialization	Panel initialization
Supported colors	Multiple colors and monochrome (BW)	Monochrome (BW)	Monochrome (BW)
Image data upload	Full screen image New image buffer with all 0x00 buffer	Full screen image Previous image buffer and new image buffer	Partial window image Previous image buffer and new image buffer
Panel update	Whole screen Flashing effect	Whole screen Fast mode	Partial window Fast mode
Image quality	Optimal quality	Optimal quality & Possible ghosting	Visible ghosting (worse than fast update)
Upload image speed	Slow	Slow	Fast
Update image speed	Slow	Fast	Fast
Overall speed	Slow	Faster	A bit faster than Fast Update
Lifespan impact speed	No	No	Yes

Find out more about

As fast (partial) update mode may not be suitable for every application, it is important to understand how they are implemented and assess the potential consequences of implementing them.