1. Guangdong Provincial Key Laboratory of Optical Information Materials and Technology and Institute of Electronic Paper Displays South China Academy of Advanced Optoelectronics, South China Normal University Guangzhou 510006 P. R. China
2. Shenzhen Guohua Optoelectronics Tech. Co. Ltd. Shenzhen 518110 China
3. Academy of Shenzhen Guohua Optoelectronics Shenzhen 518110 China
4. National Center for International Research on Green Optoelectronics South China Normal University Guangzhou 510006 P. R. China