Haiyan Gu

Threshold and grayscale stability of Microcup® electronic paper

Plastic passive matrix (PM) and active matrix (AM) electronic paper displays (EPDs) have been prepared by SiPix’s Microcup roll-to-roll manufacturing processes using ITO/PET films. The Microcup displays have shown outstanding environmental stability and excellent physico-mechanical properties such as scratch, impact and flexure resistances even in high temperature and humidity conditions. A PMEPD recently prepared on inexpensive row-and-column patterned ITO/PET films has shown a contrast ratio of ≥10, ton ≤30 msec at ≤40 V, and a threshold voltage of ≥15 V. More than 8 levels of grayscale with outstanding bistability have been demonstrated by either pulse width or pulse count modulation. No noticeable degradation of the mid-tone images has been observed even after the power was turned off for more than 5 days. Moreover, the electro-optical responses, particularly the threshold voltage and gamma of the PMEPDs remain essentially the same within a wide range (20-60°C) of operation temperature.