Author Affiliations

Hirofumi Sukeda,¹ Hiroyuki Tsuchinaga,¹ Satoshi Tanaka,¹ Toshio Niihara,¹ Shigeru Nakamura,¹ Seiichi Mita,¹ Yukinori Yamada,² Norio Ohta,² and Mitsugi Fukushima³

¹Central Research Laboratory, Hitachi Ltd., 1-280 Higashi-Koigakubo, Kokubunji, Tokyo, 185 Japan, Phone : +423-23-1111, Fax. : +423-27-7705

²Tsukuba Research Laboratory, Hitachi Maxell Ltd., 6139-1 Ohnogo, Mitsukaido, Ibaraki, 300-25 Japan, Phone : +297-24-1125, Fax. : +297-24-5269

³1st Research Dept., Nippon Columbia Co., Ltd., 5-1 Minato-cho, Kawasaki-ku, Kawasaki, 210 Japan, Phone : +44-211-7909, Fax. : +44-244-2260