公开(公告)号：EP0838041A1

公开(公告)日：1998-04-29

申请号：EP97923593.0

申请日：1997-05-07

申请人： QUANTUM CORPORATION

发明人： HAYS, Nathan, J. ,  HENSON, James, A. ,  CARPENTER, Christopher, M. ,  AKIN, William, R., Jr. ,  EHRLICH, Richard, M. ,  BEAZLEY, Lance, D.

IPC分类号： G03H1 ,  G11B7 ,  G11C13

CPC分类号： G11B7/00781 ,  G03H1/28 ,  G11B7/0065

摘要： A method of holographic recording in a photorefractive medium wherein stored holograms may be retrieved with maximum signal to noise ratio (SNR) is disclosed. A plurality of servo blocks containing position feedback information is recorded in the crystal (200) and made non-erasable by heating the crystal (300). The servo blocks are recorded at specific increments, either angular or frequency, depending whether wavelength or angular multiplexing is applied, and each servo block is defined by one of five patterns. Data pages are then recorded at positions or wavelengths enabling each data page to be subsequently reconstructed with servo patterns which provide position feedback information. The method of recording data pages and servo blocks is consistent with conventional practices. In addition, the recording system also includes components (e.g. voice coil motor) which respond to position feedback information and adjust the angular position of the reference angle of a reference beam to maximize SNR by reducing crosstalk, thereby improving storage capacity.

公开(公告)号：EP0804846A1

公开(公告)日：1997-11-05

申请号：EP96936732.0

申请日：1996-10-17

申请人： QUANTUM CORPORATION

发明人： LEIS, Michael, D. ,  PATAPOUTIAN, Ara ,  VEA, Mathew, P. ,  EHRLICH, Richard, M. ,  FISHER, Kevin, D. ,  HENSON, James, A. ,  AKIN, William, R., Jr.

IPC分类号： G11B20 ,  G11B5 ,  G11B21 ,  G11B27 ,  H03M13 ,  H04L25

CPC分类号： G11B20/10009 ,  G11B5/5526 ,  G11B5/59627 ,  G11B5/5965 ,  G11B5/59655 ,  G11B5/59688 ,  G11B20/1833 ,  G11B21/083 ,  G11B27/3027 ,  G11B2220/20 ,  H04L25/4904

摘要： A magnetic disk drive (10) data storage disk (16) defines recording tracks divided into data sectors by narrow servo spokes. A data sector lying between servo spokes is recorded with user data encoded in accordance with a code having a predetermined distance and user data code rate. Each servo spoke of the recording area has at least one servo information field encoded in a wide bi-phase code pattern. The disk drive (10) further includes a synchronous sampling data detection channel having a data transducer head (26) positioned by a servo-controlled actuator (67) over the recording track, a preamplifier (28) for receiving electrical analog signals magnetically induced by the data transducer head (26) from flux transitions present in at least the servo information field, a digital sampler (46) for synchronously sampling the electrical analog signals to produce digital samples, and wide bi-phase decoding circuitry (52) coupled to receive digital samples from the synchronous sampling data detection channel for decoding the wide bi-phase code pattern.