发明授权
US5844872A Method and apparatus for high speed data recovery from CD-ROMS or like
disks of varying qualities
失效
用于从CD-ROM或类似不同质量的磁盘高速数据恢复的方法和装置
- 专利标题: Method and apparatus for high speed data recovery from CD-ROMS or like disks of varying qualities
- 专利标题(中): 用于从CD-ROM或类似不同质量的磁盘高速数据恢复的方法和装置
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申请号: US880910申请日: 1997-06-23
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公开(公告)号: US5844872A公开(公告)日: 1998-12-01
- 发明人: Mitsumasa Kubo , Yuichi Sakamoto , Masashi Tanaka
- 申请人: Mitsumasa Kubo , Yuichi Sakamoto , Masashi Tanaka
- 申请人地址: JPX Tokyo
- 专利权人: TEAC Corporation
- 当前专利权人: TEAC Corporation
- 当前专利权人地址: JPX Tokyo
- 优先权: JPX8-199717 19960710; JPX8-327746 19961122
- 主分类号: G11B19/28
- IPC分类号: G11B19/28 ; G11B7/0037 ; G11B7/095 ; G11B19/02 ; G11B7/00
摘要:
CD-ROMS of poor quality, such as those having eccentric center holes or uneven weight distributions circumferentially, tend to overload b tracking and focusing servos and to invite read errors and retries. Each CD-ROM on being loaded into a CD-ROM drive is therefore checked as to its quality preparatory to reading. The disk is first rotated at eight times the standard audio CD speed, with both tracking and focusing servo gains set at matching values. If then at least either servo malfunctions, the disk is of poor quality, fit for reading at four or two times the standard audio CD speed. If both servos function normally, on the other hand, then the disk quality is rechecked at the same speed as before but with the servo gains lowered six decibels. A malfunctioning of at least either servo at this time indicates that the disk is of intermediate quality, to be read at eight times the standard audio CD speed. On the other hand, if both servos still function normally, the disk Is of good quality, suitable for reading at 12 times the standard audio CD speed.
公开/授权文献
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