JP4501934B2 - Optical disc recording / reproducing apparatus and recording / reproducing method thereof - Google Patents

Description

  The present invention relates to an optical disc recording / reproducing apparatus for recording / reproducing information on both the land track and the groove track of an optical disc having a land track and a groove track, and a recording / reproducing method thereof.

An optical disc recording / reproducing apparatus for recording / reproducing information on / from an optical disc in which groove tracks and land tracks are alternately formed in a spiral shape or a concentric shape is described in Patent Document 1.
In Patent Document 1, land tracks and groove tracks are alternately formed, and an address wobble in which auxiliary information such as address information is provided on one side wall of each of the land track and the groove track is shifted in the track direction to meander or An optical disk is described in which a wobble for synchronization having a constant period is formed on the side walls other than those formed by unevenness and having address wobbles. Information can be recorded on both land tracks and groove tracks.
Furthermore, an optical disc recording / reproducing apparatus is described in which auxiliary information such as address information and synchronization signals can be easily recognized by an address wobble and a constant period wobble, and a stable periodic clock can be extracted.

JP 2003-178464 A

  However, there are cases where the wobble signal obtained from each wobble is easily affected by the recording state of the land track or groove track on the inner circumference side of the trace (scanning) and the adjacent land track, and accurate auxiliary information cannot be obtained. there were.

This will be described in detail with reference to FIGS.
FIG. 5 is a plan view showing recorded and unrecorded areas of land tracks and groove tracks. In FIG. 5, the hatched portion is the recorded area, the vertical direction in the figure indicates the radial direction of the optical disk, and the horizontal direction in the figure indicates the track direction of the optical disk.

  6A shows the address wobble signal Wa obtained when recording the address wobble of the groove track with the recording laser beam, and FIG. 6A shows the groove with the reproduction laser beam. Address wobble signals obtained when reproducing the track address wobble are shown.

  FIG. 6A shows an address wobble signal obtained when recording / reproducing the address wobble of the groove track by the recording / reproducing laser beam, and FIG. 6B shows a binary signal obtained by binarizing the address wobble signal. FIG. 6C shows the design value of the binarized address wobble signal.

  (A) of the same figure is an example in the case where recording is performed on both adjacent tracks, and (b) is an example in the case where recording is performed on only one adjacent track. Even if the address wobble is the same, there is a drop in the amount of light depending on the recording state. If this wobble signal is binarized with a certain threshold value, the actual measurement value is different from the design value as shown in (b) of FIGS. Become.

  As shown in FIG. 5, an address wobble provided with address information of the groove track is formed on a part of one side (one side wall) of the groove track, and an address of the land track is formed on a part of one side of the land track. An address wobble with information is formed. In addition to the address wobbles of the groove track and land track, wobbles having a fixed period are formed.

  When reproducing the address wobble signal from the address wobble formed on the side wall of the groove track while scanning the groove track of the optical disk with the recording / reproducing laser beam, the reproduced laser beam is applied to the land tracks on both sides of the groove track. Irradiated to straddle.

  The land track and groove track have a recorded area and an unrecorded area, but the reflectance of the recording / reproducing laser beam is lower in the recorded area than in the unrecorded area. For this reason, the amount of reflected light reflected by the recorded area is smaller than the amount of reflected light reflected by the unrecorded area.

  When the address wobble signal obtained from the address wobble is binarized with a constant threshold L, as shown in FIG. 6A, the binarized signal indicates whether the groove track or the adjacent land track has been recorded or not recorded. Since the level of the light amount changes depending on the above, the value as designed as shown in FIG. 6C cannot be obtained, which causes a problem that erroneous detection occurs and auxiliary information such as address information cannot be obtained accurately. The same applies to the case where the address wobble of the land track is reproduced.

  Therefore, the present invention has been made to solve the above-described problems, and it is stable regardless of whether the track adjacent to the track scanned by the recording / reproducing laser beam is an unrecorded region or a recorded region. An object of the present invention is to provide an optical disc recording / reproducing apparatus and a recording / reproducing method thereof which can obtain auxiliary information accurately.

In order to achieve the above object, the present invention provides the following (1) and (2).
(1) Recording of information on both the groove track and the land track of the optical disk in which the groove track and the land track are alternately formed and auxiliary information is formed by wobble on the side wall of the groove track or the land track, or In an optical disc recording / reproducing apparatus for reproducing recorded information,
When the track is scanned by the recording or reproduction light is the groove track, and records information on the groove track, the optical pickup for generating a wobble reproduction signal of the groove track,
An address wobble detection unit for detecting an address wobble signal related to an address wobble on a side wall of the groove track from a reproduction signal of the wobble of the groove track generated by the optical pickup;
An adjacent address acquisition unit that calculates the address of the land track adjacent to the groove track in the same phase as the next address wobble of the groove track with respect to the auxiliary information obtained immediately before from the format of the optical disc;
A recording information storage unit for storing unrecorded data indicating whether the groove track and the land track adjacent to the groove track are in an unrecorded state or a recorded state;
A recording state measuring unit for measuring a recording state or an unrecorded state while scanning the groove track and the land track adjacent to the groove track;
From the acquired defect management information, a defect information acquisition unit that acquires defect information in the scanned address portion of the land track adjacent to the groove track and the groove track;
For the address portion determined to have defect information by the defect information acquisition unit, actually recorded unrecorded information selected by the recording state measurement unit is selected, and when it is determined that there is no defect, the recorded information storage unit A recorded information acquisition means switching unit for selecting stored unrecorded data; and
Information on the recording state corresponding to the address of the land track adjacent to the groove track calculated by the adjacent address acquisition unit is acquired from the recorded unrecorded information or recorded unrecorded data selected by the recorded information acquisition unit switching unit. An adjacent recording state acquisition unit,
A threshold setting unit that obtains a threshold so as to be at the center position of the amplitude of the address wobble signal based on the recording state information of the land track acquired by the adjacent recording state acquisition unit;
A binarization setting unit that binarizes the address wobble signal based on the threshold set by the threshold setting unit for the address wobble signal detected by the address wobble detection unit;
An address information reproducing unit for reproducing the auxiliary information from the address wobble signal binarized by the binarization setting unit;
Optical disc recording and reproducing apparatus characterized by Ru with a.
(2) Recording information on both the groove track and the land track of the optical disk in which the groove track and the land track are alternately formed and auxiliary information is formed by wobble on the side wall of the groove track or the land track, or In an optical disc recording / reproducing method for reproducing recorded information,
When the track is scanned by the recording or reproduction light is the groove track, by using the optical pickup, records the information on the groove track, and the reproduction signal generation step of generating a wobble reproduction signal of the groove track,
An address wobble detection step of detecting an address wobble signal related to an address wobble on the side wall of the groove track from the reproduction signal of the wobble of the groove track generated in the reproduction signal generation step;
An adjacent address acquisition step for calculating the address of the land track adjacent to the groove track in the same phase as the next address wobble of the groove track with respect to the auxiliary information obtained immediately before from the format of the optical disc;
A recording information storage step of storing recorded unrecorded data indicating whether the groove track and the land track adjacent to the groove track are in an unrecorded state or a recorded state;
A recording information measuring step for measuring a recorded state or an unrecorded state while scanning the groove track and the land track adjacent to the groove track;
From the acquired defect management information, a defect information acquisition step of acquiring defect information in the scanned address portion of the land track adjacent to the groove track and the groove track;
Wherein for the address portion that is determined to be defective information by the defect information acquisition step to select whether or not recording information measured by said recording information measurement step, if it is determined that there is no defect in the record information storage step A recording information acquisition means switching step for selecting stored unrecorded data; and
Information on the recording state corresponding to the address of the land track adjacent to the groove track calculated in the adjacent address acquisition step is acquired from the unrecorded information or unrecorded data selected in the recording information acquisition means switching step. An adjacent recording state acquisition step,
A threshold setting step for obtaining a threshold so as to be at the center position of the amplitude of the address wobble signal, based on the information on the recording state of the land track acquired in the adjacent recording state acquisition step ;
A binarization setting step for binarizing the address wobble signal based on the threshold value for the address wobble signal detected in the address wobble detection step ;
An address information reproduction step of reproducing the auxiliary information from the address wobble signal binarized in the binarization setting step ;
Optical disc recording and reproducing method characterized by comprising a.

  According to the present invention, the recording state data of the track to be traced and the adjacent track is acquired in advance, and the defect management information is used to acquire an unrecorded recording in an area that is considered to be low in reliability of the acquired information, Since the threshold value for binarization of the address wobble signal detected by the address wobble detection unit is set based on the information, whether the track adjacent to the track scanned by the recording / reproducing laser beam is an unrecorded area or a recorded area Therefore, it is possible to provide an optical disc recording / reproducing apparatus capable of obtaining auxiliary information stably and accurately regardless of whether or not.

  Further, according to the present invention, the recording state data of the track to be traced and the adjacent track are acquired in advance, and the unrecorded recording is acquired by actual measurement for an area considered to be low in reliability of the acquired information by the defect management information. Since the binarization threshold value of the address wobble signal detected based on the information is set, it is determined whether the track adjacent to the track scanned by the recording / reproducing laser beam is an unrecorded area or a recorded area. It is possible to provide an optical disc recording / reproducing method capable of obtaining auxiliary information stably and accurately regardless of the method.

Example 1
An optical disk recording / reproducing apparatus according to a first embodiment of the present invention will be described below with reference to FIGS.
FIG. 1 is a diagram showing an optical disc recording / reproducing apparatus according to an embodiment of the present invention, FIG. 2 is a diagram for explaining binarization of an address wobble signal, and FIG. 3 is an enlarged view of a groove track and a land track of an optical disc.
FIG. 4 is a diagram showing recorded and unrecorded areas of land tracks and groove tracks.

  Hereinafter, as an example when recording / reproducing on the groove track, description of a laser driving circuit, a recording pulse generation circuit, and the like other than the circuit for detecting auxiliary information is omitted.

  As shown in FIGS. 1 and 3, the optical disc recording / reproducing apparatus 1 includes a laser element that emits a laser beam for recording or reproduction, and outputs a recording signal for recording information on the groove track of the optical disc D, or An optical pickup 2 for photoelectrically converting the wobble reproduction signal of the groove track, detecting the amount of reflected light from the groove track and land track, and the address of the side wall of the groove track from the reproduction signal of the wobble of the groove track obtained by the optical pickup 2 An address wobble detection unit 3 that detects wobbles and generates an address wobble signal, an adjacent address acquisition unit 5 that calculates addresses of land tracks adjacent to both sides of a groove track scanned with a recording / reproducing laser beam, and a groove track When the recording / reproducing laser beam is scanned, the groove track A recording information storage unit 4 that stores recorded information in a minimum unit (ECC block); a recording state measurement unit 12 that measures a recording unrecorded state while tracing a groove track and a land track adjacent to the groove track; The defect information acquisition unit 11 that acquires defect information at a predetermined address of the groove track and the land track adjacent to the groove track from the defect management information, and the portion that is determined to be defective by the defect information acquisition unit 11 are recorded. Recording information acquisition means switching unit 13 for selecting recorded unrecorded information selected by the state measuring unit 12 and selecting recorded unrecorded data stored in the recorded information storage unit 4 when it is determined that there is no defect; The land track adjacent to the groove track calculated by the track and adjacent address acquisition unit 5 Recording information corresponding to a dress is acquired by means selected by the recording information acquisition means switching unit 13, and information on the recording state of the groove track and land track acquired by the adjacent recording state acquisition unit 6 is acquired. And a threshold value setting unit 7 for obtaining a threshold value for binarizing the address wobble signal.

  Further, the optical disc recording / reproducing apparatus 1 includes a binarization unit 8 that binarizes the address wobble signal generated by the address wobble detection unit 3 based on the threshold set by the threshold setting unit 7, and the binarization unit 8. Based on the address information reproducing unit 9 that reproduces auxiliary information such as address information from the binarized address wobble signal and the auxiliary information such as address information reproduced by the address information reproducing unit 9, recording and reproduction processing is performed. It is comprised from the control part 10. FIG.

  Next, the operation will be described with reference to FIG. 1, FIG. 3, and FIG.

  As shown in FIG. 3, a laser beam for recording / reproduction is emitted from a laser element built in the optical pip-up 2 and irradiated so as to straddle a land track adjacent to the groove track.

  The reflected light reflected by the groove track and the land track is photoelectrically converted by a photodetector (not shown) in the optical pickup 2 to generate a recording / reproducing signal of information recorded on the groove track, and the wobble signal of the groove track. Is generated.

  The address wobble signal is detected by the address wobble detector 3 from the generated wobble signal and output to the binarizer 8.

  On the other hand, the recording information storage unit 4 updates recording information data indicating whether recording has been performed or not recorded for each recording unit (ECC block) indicated by a bitmap at the time of recording.

  The defect information acquisition unit 11 acquires defect information at a predetermined address of a groove track and a land track adjacent to the groove track from defect management information or the like. In the defect area obtained by the defect information acquisition unit 11, recording is performed due to the presence of a defect or the like as shown in FIG. 4 in addition to a portion where the data is recorded but the error rate is poor and the data is not reliable. This includes cases where the recording is incomplete and unrecorded.

  Therefore, it is expected that there is a case where the actual state does not coincide with the unrecorded information stored in the recorded information storage unit 4 in a defective part. Therefore, it is effective to confirm unrecorded recording by actual measurement for the defective portion.

  The recording state measuring unit 12 measures the unrecorded state while tracing the groove track and the land track adjacent to the groove track.

  The recorded information acquisition means switching unit 13 selects actually recorded unrecorded information by the recording state measuring unit 12 for the portion determined to be defective by the defect information acquiring unit 11, and if it is determined that there is no defect The non-recorded data stored in the recorded information storage unit 4 is selected.

  The adjacent recording state acquisition unit 6 acquires the recording information corresponding to the address of the land track obtained by the groove track and the adjacent address acquisition unit 5 from the information selected by the recording information acquisition means switching unit 13, and this recording information Is output to the threshold setting unit 7.

  The threshold setting unit 7 selects an optimum threshold based on the recording information of the recording state of the land track adjacent to the groove track and the adjacent recording state acquisition unit 6 and outputs it to the binarization unit 8.

  The threshold selected by the threshold setting unit 7 is determined by the reflected light amount level of the address wobble signal as shown in FIG. The amount of reflected light varies depending on the combination of the recording state of the groove track and the land track adjacent thereto, but the relationship between the reflected light amount and the recording state or unrecorded state of the groove track and the land track adjacent thereto is previously stored in a data table. The threshold value can be determined using this data table. Further, the relationship between the reflected light amount and the unrecorded state of the track may be acquired by learning when the optical disk is loaded instead of the data table and stored in a storage unit (not shown).

  The binarization unit 8 binarizes the address wobble signal based on the threshold set by the threshold setting unit 7 based on the address wobble signal detected by the address wobble detection unit. As shown in FIG. 2B, the binarized address wobble signal can have a value as the design value shown in FIG. 2C even when the levels are different.

  The address information reproducing unit 9 reproduces auxiliary information such as address information from the address wobble signal binarized by the binarizing unit 8.

  In the adjacent address acquisition unit 5, land tracks adjacent to both sides of the groove track in phase with the next wobble address of the wobble address next to the address wobble of the groove track from the auxiliary information obtained by the address information reproducing unit 9 based on the format of the optical disk. It is calculated using the address.

  The control unit 10 can perform recording and reproduction by processing information based on the auxiliary information reproduced by the address information reproducing unit 9 and the address obtained by the adjacent address obtaining unit 5.

  As described above, the optical disc recording / reproducing apparatus 1 according to the first embodiment of the present invention acquires in advance the recording state data of the track to be traced and the adjacent track, and the reliability of the acquired information is low by the defect management information. In the region considered to be unrecorded, a record-unrecorded laser beam is obtained by actual measurement, and the threshold value for binarization of the address wobble signal detected by the address wobble detection unit 9 is set based on the information. The auxiliary information can be obtained stably and accurately regardless of whether the track adjacent to the track to be scanned is an unrecorded area or a recorded area.

  In the first embodiment of the present invention, the case where the track to be recorded / reproduced is a groove track has been described as an example, but the same applies to the case where the track to be recorded / reproduced is a land track.

(Second embodiment)
In the reproduction of the optical disc recording / reproducing apparatus 1 of the second embodiment of the present invention, it is considered that the recording state data of the track to be traced and the adjacent track is acquired in advance, and the reliability of the acquired information is low by the defect management information As for the area, a record unrecorded is obtained by actual measurement, and the threshold value for binarization of the address wobble signal detected by the address wobble detection unit 9 is set based on the information. The auxiliary information can be obtained stably and accurately regardless of whether the track adjacent to the unrecorded area or the recorded area.

  In the second embodiment of the present invention, the case where the track to be reproduced is a groove track has been described as an example, but the same applies to the case where the track to be reproduced is a land track.

It is a figure which shows the optical disk recording / reproducing apparatus in embodiment of this invention. It is a figure for demonstrating binarization of an address wobble signal. It is the figure which expanded the groove track and land track of the optical disk. It is a figure which shows the recorded area | region and unrecorded area | region of a land track and a groove track when there exists a defect. It is a figure which shows the recorded area | region and unrecorded area | region of a land track and a groove track. When recording / reproducing an address wobble of a groove track with a recording / reproducing laser beam, an address wobble signal obtained and a binarized signal obtained by binarizing the address wobble signal are shown. FIG. The address wobble signal obtained when recording / reproducing the address wobble of the groove track by the laser beam, FIG. 5B is a binary signal obtained by binarizing the address wobble signal, and FIG. This is the designed value of the address wobble signal.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Optical disk recording / reproducing apparatus 2 ... Optical pick-up 3 ... Address wobble detection part 4 ... Recording information storage part 5 ... Adjacent address acquisition part 6 ... Adjacent recording state acquisition part 7 ... Threshold setting part 8 ... Binarization setting part 9 ... Address Information reproduction unit 10 ... control unit 11 ... defect information acquisition unit 12 ... recording state measurement unit 13 ... recording information acquisition means switching unit D ... optical disc

Claims (2)

Information is recorded or recorded on both the groove track and the land track of the optical disc in which the groove track and the land track are alternately formed and auxiliary information is formed by wobble on the side wall of the groove track or the land track. In an optical disc recording / reproducing apparatus for reproducing information,
When the track is scanned by the recording or reproduction light is the groove track, and records information on the groove track, the optical pickup for generating a wobble reproduction signal of the groove track,
An address wobble detection unit for detecting an address wobble signal related to an address wobble on a side wall of the groove track from a reproduction signal of the wobble of the groove track generated by the optical pickup;
An adjacent address acquisition unit that calculates the address of the land track adjacent to the groove track in the same phase as the next address wobble of the groove track with respect to the auxiliary information obtained immediately before from the format of the optical disc;
A recording information storage unit for storing unrecorded data indicating whether the groove track and the land track adjacent to the groove track are in an unrecorded state or a recorded state;
A recording state measuring unit for measuring a recording state or an unrecorded state while scanning the groove track and the land track adjacent to the groove track;
From the acquired defect management information, a defect information acquisition unit that acquires defect information in the scanned address portion of the land track adjacent to the groove track and the groove track;
For the address portion determined to have defect information by the defect information acquisition unit, actually recorded unrecorded information selected by the recording state measurement unit is selected, and when it is determined that there is no defect, the recorded information storage unit A recorded information acquisition means switching unit for selecting stored unrecorded data; and
Information on the recording state corresponding to the address of the land track adjacent to the groove track calculated by the adjacent address acquisition unit is acquired from the recorded unrecorded information or recorded unrecorded data selected by the recorded information acquisition unit switching unit. An adjacent recording state acquisition unit,
A threshold setting unit that obtains a threshold so as to be at the center position of the amplitude of the address wobble signal based on the recording state information of the land track acquired by the adjacent recording state acquisition unit;
A binarization setting unit that binarizes the address wobble signal based on the threshold set by the threshold setting unit for the address wobble signal detected by the address wobble detection unit;
An address information reproducing unit for reproducing the auxiliary information from the address wobble signal binarized by the binarization setting unit;
Optical disc recording and reproducing apparatus characterized by Ru with a. Information is recorded or recorded on both the groove track and the land track of the optical disc in which the groove track and the land track are alternately formed and auxiliary information is formed by wobble on the side wall of the groove track or the land track. In an optical disc recording / reproducing method for reproducing information,
When the track is scanned by the recording or reproduction light is the groove track, by using the optical pickup, records the information on the groove track, and the reproduction signal generation step of generating a wobble reproduction signal of the groove track,
An address wobble detection step of detecting an address wobble signal related to an address wobble on the side wall of the groove track from the reproduction signal of the wobble of the groove track generated in the reproduction signal generation step;
An adjacent address acquisition step for calculating the address of the land track adjacent to the groove track in the same phase as the next address wobble of the groove track with respect to the auxiliary information obtained immediately before from the format of the optical disc;
A recording information storage step of storing recorded unrecorded data indicating whether the groove track and the land track adjacent to the groove track are in an unrecorded state or a recorded state;
A recording information measuring step for measuring a recorded state or an unrecorded state while scanning the groove track and the land track adjacent to the groove track;
From the acquired defect management information, a defect information acquisition step of acquiring defect information in the scanned address portion of the land track adjacent to the groove track and the groove track;
Wherein for the address portion that is determined to be defective information by the defect information acquisition step to select whether or not recording information measured by said recording information measurement step, if it is determined that there is no defect in the record information storage step A recording information acquisition means switching step for selecting stored unrecorded data; and
Information on the recording state corresponding to the address of the land track adjacent to the groove track calculated in the adjacent address acquisition step is acquired from the unrecorded information or unrecorded data selected in the recording information acquisition means switching step. An adjacent recording state acquisition step,
A threshold setting step for obtaining a threshold so as to be at the center position of the amplitude of the address wobble signal, based on the information on the recording state of the land track acquired in the adjacent recording state acquisition step ;
A binarization setting step for binarizing the address wobble signal based on the threshold value for the address wobble signal detected in the address wobble detection step ;
An address information reproduction step of reproducing the auxiliary information from the address wobble signal binarized in the binarization setting step ;
Optical disc recording and reproducing method characterized by comprising a.

Images