The researchers have developed various colored inks, including cyan, magenta, yellow and black inks, which can yield any combination colour when stacked on top of each other in a layered structure.
Based on electrowetting, a coarse resolution (32x32 pixels over a 1cm 2 each) 40x40cm tiled e-paper outdoor billboard was demonstrated running at a refresh rate of 50Hz, exhibiting a variety of colours and coloured video content.
According to Professor Alex Henzen, the core member of the SCNU team and technical leader on e-paper, outdoor billboards made of such an electrowetting based reflective e-paper technology would take up less than 1% of the power consumption of LED and TFT-LCD displays of a similar size, making the new technology very attractive for a large signage market.
The researchers have also developed higher resolution electrowetting-based monochrome video e-paper displays on an a-Si TFT substrate, including a 4.2-inch version manufactured on the institute's proprietary Gen2.5 pilot line.
The display used a prototype spacer between the cover plate and the baseplate so as to improve its display performance.
All the materials and processes for enabling the samples/products, including front-panel related colour inks, functional films, fabrication process, multilayer coupling, driving waveform and the final integration have been secured with hundreds of patents, the researchers note.
South China Normal University - http://www.csc.edu.cn