1. Department of Intelligent Systems Engineering, Ibaraki University, Nakanarusawa 4-12-1, Hitachi 316-8511, Japan
2. Product Development Div.7, SMC Corp., Akihabara UDX15F, 4-14-1, Sotokanda, Chiyoda-ku 101-0021, Japan
3. Imaging Products Business Unit, Tamron Co., Ltd., 1385 Hasunuma, Minuma-ku, Saitama, Saitama City, 337-8556, Japan