1. Department of Electronics Engineering, National Chiao Tung University, Hsinchu City 30010, Taiwan
2. Department of Electro-Physics, National Chiao Tung University, Hsinchu City 30010, Taiwan
3. Department of Mechatronic Engineering, National Taiwan Normal University, Taipei, 106, Taiwan
4. Himax Technologies, Inc., Tainan City 74148, Taiwan