Pervasive Displays (PDi), a world leader in e-paper displays today announced the availability of partial update display driving technology across its range of electronic ink e-paper displays (EPD). E-paper is a bistable technology, which means that energy is only consumed when the display is changing. Once it has changed, the display consumes no energy and continues to show information, even when disconnected from its power source. Rather than update the whole display image when part of it changes, known as a global or full update, a partial update (or local update) only refreshes the pixels that need to be changed. This approach greatly enhances the user’s visual experience since it does not create the blinking effect typically associated with a global update when all pixels are refreshed. In addition, this method of update takes less time and consumes much less power, further improving the user’s visual interaction with the display. A partial update cycle takes around 300 – 600 ms which is a quarter of the time typically required for a global update on a similar monochrome display. The partial update uses two data buffers to contain the current and new images, and by comparing these, the pixels that require updating are identified.
The partial update display driving technology has been integrated into the graphics libraries of the semiconductor vendors supported, these including Texas Instruments (TI) and Microchip. Examples of application areas for this type of technology are smart home devices such as thermostats and home appliances; Internet of Things (IoT) applications like alarm systems, sensor devices and public information boards; and personal devices such as name badges, healthcare devices and electronic bag tags.
A video example of the partial update being used on a variety of different display sizes with external timing controllers (eTCs) from PDi is available on the Pervasive Displays website together with the source code for use with the new EPD Extension Kit.
PDi has also implemented partial update with the TITM TivaWare Graphics Library (grlib) for its internal timing controllers (iTC) driver displays. Demo videos are available on the website for thermostat, human machine interface (HMI) and smart home applications. Developers can obtain the new EXT2 Kit from Pervasive Displays to preview the partial update effect on full images using displays with iTCs.
For further details: