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公开(公告)号：JP2001266364A
公开(公告)日：2001-09-28
申请号：JP2001045919
申请日：2001-02-22
Applicant: ST MICROELECTRONICS SA
Inventor： GRAFFOULIERE PHILIPPE
Abstract: PROBLEM TO BE SOLVED: To provide the method for controlling the positioning of a light beam incident on a track of an optical disk. SOLUTION: The beam reflected by the disk is detected by using an optical pickup furnished with a photodetector, and basic signals A, B, C, D are respectively outputted from the photodetector. The positioning error of the beam with respect to the track is obtained from the basic signal. To be more specific, two sampled secondary signals (A+C, B+D) are produced from the basic signals, and the time difference between them represents the positioning error of the beam with respect to the track. A continuous latest value of the time difference (T) between them is obtained by a sampling frequency in such a manner that a maximum value MAX of a continuous latest correlation function between two sampled secondary signals is searched.
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公开(公告)号：DE60139287D1
公开(公告)日：2009-09-03
申请号：DE60139287
申请日：2001-02-14
Applicant: ST MICROELECTRONICS SA
Inventor： GRAFFOULIERE PHILIPPE
Abstract: From elementary signals, two secondary signals (A+C;B+D) are formed, whose spacing (T) represents of a positioning error (TE) of the beam in relation to the track. From the sampling frequency, successive current values of the spacing (T) is determined during searching for the current maximum (MAX) related to the sampling frequency, for determining inter-interrelationship between the two sampled secondary signals. Independent claims are included for: (a) a device for controlling positioning of an optical beam on a data track (b) a DVD reader
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公开(公告)号：FR2825827A1
公开(公告)日：2002-12-13
申请号：FR0107446
申请日：2001-06-07
Applicant: ST MICROELECTRONICS SA
Inventor： GRAFFOULIERE PHILIPPE
IPC: G11B7/007 , G11B20/10 , G11B20/12 , G11B20/14 , G11B27/19 , G11B27/24 , G11B27/30 , G11B7/0037 , G11B7/013 , H01L27/00
Abstract: The method for indicating a sector on an optical disc (9) uses a reference (16) of M multiplets, each comprising L bits. A succession of multiplets is engraved locally at this sector on the disc. Engraving may be effected by either modifying the amplitude of the wave period of a 'groove' on the information support or by multiplying by three an initial wave frequency over the total period of the initial alternation. The method for indicating a sector on a data medium such as an optical disc (9) uses a reference (16) which consists of M multiplets, each comprising L bits. Locally at this sector on the disc a succession of multiplets is engraved. These each correspond to a first multiplet, and a second multiplet which is equal to a vector of N components, each of value +1 or -1, such that N = 2L-1, and also such that the scalar product of the vector by any other vector which is equal to another second multiplet, is not more than a+1. One of the +1 or -1 values is engraved by modifying the amplitude of the wave period of a 'groove' on the information support. One of the +1 or -1 values may be engraved by multiplying by three an initial wave frequency over the total period of the initial alternation.
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公开(公告)号：FR2833795B1
公开(公告)日：2004-04-02
申请号：FR0116380
申请日：2001-12-18
Applicant: ST MICROELECTRONICS SA
Inventor： GRAFFOULIERE PHILIPPE
Abstract: Phase errors are computed (23,37) for two states: a first dependent on phase error where symbol length is not corrected, and a second dependent on phase error where symbol length is corrected. Uncorrected length is retained if the first error minimizes a condition to pass from the first state, and corrected value retained if the second error minimizes a condition to pass from the second state.
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Patent Agency Ranking
公开(公告)号：FR2805381B1
公开(公告)日：2003-09-05
申请号：FR0002263
申请日：2000-02-23
Applicant: ST MICROELECTRONICS SA
Inventor： GRAFFOULIERE PHILIPPE
Abstract: From elementary signals, two secondary signals (A+C;B+D) are formed, whose spacing (T) represents of a positioning error (TE) of the beam in relation to the track. From the sampling frequency, successive current values of the spacing (T) is determined during searching for the current maximum (MAX) related to the sampling frequency, for determining inter-interrelationship between the two sampled secondary signals. Independent claims are included for: (a) a device for controlling positioning of an optical beam on a data track (b) a DVD reader
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公开(公告)号：FR2805382B1
公开(公告)日：2003-07-04
申请号：FR0002264
申请日：2000-02-23
Applicant: ST MICROELECTRONICS SA
Inventor： GRAFFOULIERE PHILIPPE
Abstract: the system uses application of adjustable delays in successive sampling periods to eliminate time differences. Two photodetectors are used in the positioning of a laser spot on a DVD track. The procedure for the elimination of time difference between two photodetector signals which are time-shifted includes sampling each signal (xb, yb). Each sampled signal element is delayed (xa, ya) by an adjustable delay. Working at the sampling frequency, at least one of the adjustable delays (RT1, RT2) is adjusted until there is a null time difference between the delayed signals. The final adjustable delay which is applied then provides the required indication of the time difference between the two signals.
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公开(公告)号：FR2833795A1
公开(公告)日：2003-06-20
申请号：FR0116380
申请日：2001-12-18
Applicant: ST MICROELECTRONICS SA
Inventor： GRAFFOULIERE PHILIPPE
Abstract: Phase errors are computed (23,37) for two states: a first dependent on phase error where symbol length is not corrected, and a second dependent on phase error where symbol length is corrected. Uncorrected length is retained if the first error minimizes a condition to pass from the first state, and corrected value retained if the second error minimizes a condition to pass from the second state.
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公开(公告)号：FR2805382A1
公开(公告)日：2001-08-24
申请号：FR0002264
申请日：2000-02-23
Applicant: ST MICROELECTRONICS SA
Inventor： GRAFFOULIERE PHILIPPE
Abstract: the system uses application of adjustable delays in successive sampling periods to eliminate time differences. Two photodetectors are used in the positioning of a laser spot on a DVD track. The procedure for the elimination of time difference between two photodetector signals which are time-shifted includes sampling each signal (xb, yb). Each sampled signal element is delayed (xa, ya) by an adjustable delay. Working at the sampling frequency, at least one of the adjustable delays (RT1, RT2) is adjusted until there is a null time difference between the delayed signals. The final adjustable delay which is applied then provides the required indication of the time difference between the two signals.
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公开(公告)号：FR2805381A1
公开(公告)日：2001-08-24
申请号：FR0002263
申请日：2000-02-23
Applicant: ST MICROELECTRONICS SA
Inventor： GRAFFOULIERE PHILIPPE
Abstract: From elementary signals, two secondary signals (A+C;B+D) are formed, whose spacing (T) represents of a positioning error (TE) of the beam in relation to the track. From the sampling frequency, successive current values of the spacing (T) is determined during searching for the current maximum (MAX) related to the sampling frequency, for determining inter-interrelationship between the two sampled secondary signals. Independent claims are included for: (a) a device for controlling positioning of an optical beam on a data track (b) a DVD reader
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