A Method to Improve the Lifetime of Microcapsule Electrophoretic Display Modules

Microcapsule electrophoretic display (MED) is a kind of display with the properties of reflectivity and low power consumption. It is widely used in electronic book readers, but some new applications have appeared in the Internet of Things (IoT) products. Long working time is required in IoT products because it is not easy to replace or install such displays. The main failure phenomenon is the mura that will appear after about 1 to 2 years of use. The root cause of the failure is analyzed, and the lifetime prediction models for MED are introduced. The high temperature and high humidity (HTHH) test is used to evaluate the protective effect of the packaging structure. The HTHH test result is reported for the new MED structure; it shows that the MED with the new structure involves a longer working time.

Review of Driving Waveform for Electrowetting Displays

Electrowetting display (EWD) is the most potential technology among new electronic paper technologies. It not only has the advantages of electrophoretic display (EPD) technology but also can realize color video playback. Therefore, this technology has been widely studied in recent years. Driving waveform is a voltage sequence which can drive pixels to display gray scales in EWDs. As one of the key technologies, it directly affects the display effect of pixels. In this paper, we give a review of the display principle of EWDs and the research status of driving waveforms. At the same time, the contact angle hysteresis, charge trapping, and oil splitting are also reviewed, which can provide a reference value for designing driving waveforms.

An Electrophoretic Display Driving Waveform Design for Reducing a Flicker and a Driving Time Based on the Fusion Optimization of Driving Stages

The speed of updating an image is very important for an electrophoretic display (EPD) application, but the flicker which can be produced among the process of updating an image is a main factor of affecting reading comfort for human eyes. In this paper, a new driving waveform, which was based on DC balance, was proposed to reduce the number of flicker and decrease the driving time for updating an image. Firstly, we studied properties of particles in the EPD, and the stages in the driving waveform were fused according to the driving properties of the particles. Secondly, an accurate reference was formed in the driving waveform for writing a new image, and the particle activity was guaranteed at the same time. Lastly, the driving waveform was downloaded to a real EPD waveform look-up table and the performance was compared with traditional driving waveforms. Experimental results showed that the proposed driving waveform could reduce flicker effectively and shorten the driving time by 25%, and an accurate white reference gray scale was obtained for displaying high quality images.

Blue nanocomposites coated with an ionic liquid polymer for electrophoretic displays

Electrophoretic display (EPD) is a type of flexible display which has attracted wide attention.