公开(公告)号：JP2001118273A

公开(公告)日：2001-04-27

申请号：JP29830499

申请日：1999-10-20

Applicant: SONY CORP

Inventor： FUJITA GORO

IPC: G11B7/095

Abstract: PROBLEM TO BE SOLVED: To quickly and precisely detect a tilt amount without an exclusive sensor. SOLUTION: An optical disk reproducing device 10 is provided with an optical pickup 11 reading out the digital data recorded on an optical disk an amplitude detection circuit 18 detecting the amplitude of a wobble component signal passed by a band-pass filter 14 and a tilt detection circuit 24 detecting the tilt amount. The optical disk reproducing device 10 irradiates the optical disk, with a laser beam forming a main beam spot and two sub-beam spots, and detects the amplitude of respective wobble component signals based on return beams from a signal information recording side wall by two objective beam spots among the main beam spot and two sub-beam spots and obtains the difference values of the amplitude of respective wobble component signals as a tilt instruction value.

公开(公告)号：JP2000090437A

公开(公告)日：2000-03-31

申请号：JP26147898

申请日：1998-09-16

Applicant: SONY CORP

Inventor： FUJITA GORO

IPC: G11B7/125 ,  G11B7/00 ,  G11B7/0045 ,  G11B11/10 ,  G11B11/105

Abstract: PROBLEM TO BE SOLVED: To stably and repeatedly record data. SOLUTION: When an optical disk is loaded in ST1, optimum resolution data is read out and stored. Optimum recording power is set in ST2. Specific pattern data PTD is written with optimum recording power in ST3. Specific pattern data is reproduced, and optimum reproducing power optimum in resolution is set in ST4. A recording unit for recording data is reproduced, and optimum reproducing power is discriminated for every recording unit in ST5. The ratio of optimum reproducing power to optimum reproducing power discriminated for every recording unit is calculated in ST6. Optimum recording power is compensated by using the ratio in ST7. Data is recorded with compensated recording power in accordance with respective recording units in ST8. Even if sensitivity is different from each recording unit, the recording power of a laser beam is controlled in accordance with respective recording unit, thus the data can be recorded stably and repeatedly.

公开(公告)号：JPH11273176A

公开(公告)日：1999-10-08

申请号：JP7073898

申请日：1998-03-19

Applicant: Sony Corp ,  ソニー株式会社

Inventor： FUJITA GORO ,  HIDA MINORU

IPC: G11B11/105 ,  G11B11/10

Abstract: PROBLEM TO BE SOLVED: To correctly reproduce recorded data by performing a highly accurate positioning control in a magneto-optical disk reproducing device reproducing data from a magneto-optical disk having a magnetic domain expanding layer.
SOLUTION: A reproducing magnetic field impressing means 1 impresses a reproducing magnetic field for reading the data copied on the magnetic domain exanding layer of a magneto-optical disk 2 by driving the magnetic coil 3a of a magnetic head 3 in accordance with a reference clock. As a result, recorded data can be read out with a pickup 3b. On the other hand, reference marks 2b are preliminarily provided in respective sectors 2a of the disk 2. When the magnetic head 3 comes to these sectors 2a, a reference mark reading means 4 reads out reference marks 2b and an edge detecting means 5 detects the rising and falling edges of reproduced pluses of the read reference marks 2b. A phase error detecting means 6 detects the phase error between the phase of the edge and the phase of the reproducing magnetic field and a phase correcting means 7 corrects the phase of the clock of the reproducing magnetic field based on this phase error.
COPYRIGHT: (C)1999,JPO

Abstract translation: 要解决的问题：通过在具有磁畴扩展层的磁光盘再现数据的磁光盘再现装置中执行高精度的定位控制来正确地再现记录的数据。 解决方案：再现磁场施加装置1通过根据参考时钟驱动磁头3的磁性线圈3a，印刷用于读取复制在磁光盘2的磁畴上的层上的数据的再现磁场。 结果，记录数据可以用拾取器3b读出。 另一方面，参考标记2b预先设置在盘2的相应扇区2a中。当磁头3到达这些扇区2a时，参考标记读取装置4读出参考标记2b，边缘检测装置5检测 读取的参考标记2b的再现的上升和下降沿。 相位误差检测装置6检测边缘相位与再现磁场的相位之间的相位误差，并且相位校正装置7基于该相位误差校正再现磁场的时钟的相位。

公开(公告)号：JPH11149679A

公开(公告)日：1999-06-02

申请号：JP31743897

申请日：1997-11-18

Applicant: SONY CORP

Inventor： HIDA MINORU ,  FUJITA GORO

IPC: G11B11/10 ,  G11B11/105 ,  G11B20/18

Abstract: PROBLEM TO BE SOLVED: To verify recorded data simultaneously with the recording of an over-writable optical disk being. SOLUTION: This device has a DSP 16 and a laser driver 6 controlling and a driving an optical pickup 3 and laser emission of an optical pickup 3, a magnetic super-resolution or a magnetic expansion optical disk 1, an encode/PRML decoding circuit 18 generating a recording signal, and a verifying processing circuit 21 comparing a recording signal and a reproduced signal MO from an I-V matrix 1c 5 and verifying it. In this constitution, when recording is performed, a laser beam is emitted in a pulse state, a recording pit in accordance with a recording signal is formed, at the same time, simultaneous verifying is performed by comparing a value to which a reproduced signal MO of a recording pit formed by the recording signal is sampled with the prescribed timing and a recording signal at the time by verifying processing circuit 21.

公开(公告)号：JPH1196580A

公开(公告)日：1999-04-09

申请号：JP25952097

申请日：1997-09-25

Applicant: SONY CORP

Inventor： FUJITA GORO ,  HIDA MINORU ,  WATANABE SATORU

IPC: G11B7/13

Abstract: PROBLEM TO BE SOLVED: To perform correct tracking control without lowering a light quantity by using a differential push-pull signal of a fixed spot and generating a tracking error signal canceling an offset component. SOLUTION: Although an intensity distribution of reflection light on a photodetector 27-2 becomes equal rate in upper/lower areas when the spot 31 traces a normal position, when the spot 31 traces the shifted position shown by a solid line, in the intensity distribution of the reflection light on the photodetector 27-2, respectively different area sides become stronger, and a radial push-pull signal RPP becomes smaller than zero on X1, and becomes larger than zero on X2 when the position of the spot 31 exists on the X1 on a clock mark and when it exists on the X2 on a data area. Even when the reflection optical axis of the photodetector 27-2 is shifted due to a tilt, etc., of a disk, and the offset occur on respective RPPs, these offset amounts become the same, and the offset in the tracking error signal is canceled.

公开(公告)号：JPH1125475A

公开(公告)日：1999-01-29

申请号：JP12510198

申请日：1998-05-07

Applicant: SONY CORP

Inventor： FUJITA GORO

IPC: G11B11/10 ,  G11B7/00 ,  G11B7/0045 ,  G11B7/085 ,  G11B7/09 ,  G11B11/105

Abstract: PROBLEM TO BE SOLVED: To easily discriminate whether a laser beam is located on a land part or on a groove part. SOLUTION: A land part and a groove part composing a recording track are alternately formed in the radial direction in an optical disk and a mark having phase information is recorded in the land part or the groove part. The mark CM is composed of a pair of projected parts 4a, 4b formed so as to protrude to the inside from the both end faces of the groove part 12G and the reproducing signal is obtained by reversing the polarity at the time when a laser beam PPB scans the land part 12L to the polarity at the time (SG) of scanning the groove part 12G. By the polarity of the reproducing signal, it is discriminated whether the laser beam PPB for scanning the optical disk is located in the land part 12L or in the groove part 12G. Whether the laser beam PPB is located in the land part 12L or in the groove part 12G is easily discriminated.

公开(公告)号：JPH10199044A

公开(公告)日：1998-07-31

申请号：JP1597097

申请日：1997-01-14

Applicant: SONY CORP

Inventor： FUJITA GORO ,  TERAOKA YOSHIYUKI

IPC: G11B7/24 ,  G11B7/00 ,  G11B7/0045 ,  G11B7/007 ,  G11B7/26

Abstract: PROBLEM TO BE SOLVED: To provide a disk-like recording medium capable of stably performing recording/reproducing operation even when the track pitch of a recording medium is made narrowed, and its production method. SOLUTION: Since respective servo pits Pt1 (Pt2 ) in a servo area on a disk are formed so as to be shared between adjacent tracks, and the pit width PtW of the servo pit Pt1 (Pt2 ) in the radial direction of the disk is formed so as to become wider than a regular pit width, a sufficient tracking modulation degree is secured, and the amplitude having grade capable of generating a servo clock is obtained even when a laser beam of a recording/reproducing device passes through the position being the most away from the servo pit Pt1 (Pt2 ).

公开(公告)号：JPH0668484A

公开(公告)日：1994-03-11

申请号：JP22176492

申请日：1992-08-20

Applicant: SONY CORP

Inventor： FUJITA GORO

IPC: G11B7/085 ,  G11B7/09

Abstract: PURPOSE:To perform tracking servo operation without requiring a galvano- mirror which is used for a conventional device, to reduce the size of the optical pickup device by as much as the galvano-mirror is unnecessary, and to reduce the cost since the need for the galvano-mirror is eliminated. CONSTITUTION:A fixed part 20 radiates recording tracks of an optical disk 1 with the projection light from a laser light source through a prism 12 and an objective 11 and its reflected light is photodetected by a photodetector. Further, the fixed part 20 detects a tracking error signal. A piezoelectric element 21 is applied with a voltage based upon the tracking error signal and rotates the fixed part 20 so that the optical axis of the projection light from the laser light source moves in a radius direction of the optical disk 1. Consequently, the tracking servo operation is performed.

公开(公告)号：JPH05242486A

公开(公告)日：1993-09-21

申请号：JP7548692

申请日：1992-02-26

Applicant: SONY CORP

Inventor： FUJITA GORO

IPC: G11B7/00 ,  G11B7/004 ,  G11B7/013

Abstract: PURPOSE:To accurately decide a logic by a pit when two pieces of pit lines are formed on one track in an optical disk. CONSTITUTION:A photodetector 8 is divided into four areas of an area A to D and whose output is supplied to a decoder 11. The condition of an energy distribution corresponding to a pit pattern recorded on the optical disk 1 is stored in a ROM 12 previously, and the pattern of the output of an A/D converter 10A to 10D and the pattern stored in the ROM 12 previously are compared by a decoder 11 and the nearest pattern is selected. Then, the logic corresponding to the pattern is outputted.

公开(公告)号：JPH05234083A

公开(公告)日：1993-09-10

申请号：JP7265792

申请日：1992-02-21

Applicant: SONY CORP

Inventor： FUJITA GORO

IPC: G11B7/00 ,  G11B7/004

Abstract: PURPOSE:To improve a linear recording density by calculating the exclusive OR of logic of recording data and the logic of an immediately before information pit hourly and outputting its result as reproducing data. CONSTITUTION:In formation 101110 is inputted to a terminal 1. A switch 6 is in a contact (b) only in a first clock period. An EXOR circuit 3 obtains '1' from the contact (b), and '0' from the EXOR of '1' from terminal 1. The output of the EXOR circuit 3 is delayed by one clock by a delaying circuit 4, and switched to a contact (a). Accordingly, to the circuit 3, second recording information (o) and the previous logical arithmetic value '0' from the delaying circuit 4 are inputted, and the output of the circuit 3 becomes '0'. Thereafter, the result 001011 of the same operation is obtained. When the output of the EXOR 3 is '1', a driving circuit 7 records a pit of 1001011 in a disk 9 by the laser of a head 8. First '1' is a dummy initial pit for determining the logic of an information pit. In this regard, at the time of '0', nothing is formed in the disk 9. By such constitution, linear recording density of the disk 9 can be improved.