1. Department of Photonics and Graduate Institute of Electro-Optical Engineering, College of Electrical and Computer Engineering, National Yang Ming Chiao Tung University, Hsinchu, Taiwan
2. Philips Electronics Ltd., Shatin, Hong Kong
3. Department of Photonics, Feng Chia University, Taichung, Taiwan
4. Industrial Technology Research Institute, Zhudong, Hsinchu County, Taiwan