1. School of Electronic and Electrical Engineering Kyungpook National University Daegu 41566 South Korea
2. LG Display Co. Ltd. Paju Gyeonggi-do 10845 South Korea
3. Department of Sensor and Display Engineering Kyungpook National University Daegu 41566 South Korea
4. College of Art & Design Ewha Womans University Seoul 03760 South Korea
5. School of Electronics Engineering Kyungpook National University Daegu 41566 South Korea