[1] Chosun Univ, Coll Engn, Dept Photon Engn, Kwangju 501759, South Korea
[2] Honam Univ, Dept Elect & Photon Engn, Kwangju 506714, South Korea
[3] Nambu Univ, Dept Biomed Engn, Kwangju 506824, South Korea
[4] Nambu Univ, Inst Photoelect Technol, Kwangju 506824, South Korea
[5] Korea Inst Sci & Technol Informat, Seoul 130741, South Korea