发明名称 Method of and device for recording and playing back an optical disk having a test playback region utilizing pits of minimum size for controlling the power of the laser
摘要 In a method of reproducing information from an optical disk, the disk is scanned with a laser beam forming a light spot on the disk, at least some of the recording pits being smaller in size than the light spot, the laser beam heating the disk so that effective detection area being formed at only part of the light spot, a sequence of preformatted pits of a minimum size are formed, playback signals are produced in accordance with a reflected light from the disk, and a power of the laser beam is so controlled so as to maximize the level of the playback signals produced from the reflected light from the sequence of pits of the minimum size. In another method using a magneto-optical disk, information is recorded by scanning the disk with a laser beam, each of the recording pits being substantially crescent-shaped, the direction of rotation during playback is opposite to the direction of rotation during playback, and the order of bits forming the information is reversed either during the playback or recording.
申请公布号 US5699342(A) 申请公布日期 1997.12.16
申请号 US19950385310 申请日期 1995.02.07
申请人 MITSUBISHI DENKI KABUSHIKI KAISHA 发明人 YAGI, KOSUKE;EGUSA, NAOYUKI;NAGASAWA, MASATO
分类号 G11B7/005;G11B7/125;G11B11/105;(IPC1-7):G11B7/00;G11B11/00 主分类号 G11B7/005
代理机构 代理人
主权项
地址
您可能感兴趣的专利