JP2008234719A - Recording power correction method, recording method, program, recording medium, optical disc apparatus, information processing apparatus, and optical disc - Google Patents

Abstract

A recording power for recording information on an optical disk is corrected to an appropriate recording power.
When recording on an optical disc is performed on continuous tracks, a plurality of continuous tracks including boundaries between recorded tracks and unrecorded tracks in a plurality of tracks are set as an evaluation region, and reflection from the evaluation region is performed. The reflectance is obtained for each track with light (step S415). Then, information on the deviation of the recording power from the appropriate recording power when information is recorded on the recorded track is obtained from the reflectance of each track (steps S417 and S419), and recording is performed based on the information on the deviation. The power is corrected (step S421). Here, the recording power is corrected using information from multiple continuous tracks near the boundary between the recorded and unrecorded tracks, so the recording power when recording information on the optical disk is corrected to an appropriate recording power. It becomes possible to do.
[Selection] Figure 11

Description

  The present invention relates to a recording power correction method, a recording method, a program, a recording medium, an optical disc apparatus, an information processing apparatus, and an optical disc, and more particularly, corrects recording power when information is recorded on an optical disc having a plurality of tracks. Recording power correction method, recording method for recording information on an optical disc having a plurality of tracks, an optical disc apparatus capable of recording information on the optical disc, an information processing apparatus including the optical disc apparatus, a program used in the optical disc apparatus, and the program The present invention relates to a recorded recording medium and an optical disc having a plurality of tracks on which information can be recorded.

  In recent years, with the advancement of digital technology and the improvement of data compression technology, as a medium for recording information (hereinafter also referred to as “content”) such as music, movies, photos, and computer software, DVD (Digital Versatile Disc), etc. Optical discs have attracted attention, and along with the reduction in price, optical disc apparatuses that use optical discs as information recording media have become widespread.

  The optical disc device is provided with an optical pickup device for irradiating the recording surface of the optical disc with laser light and receiving reflected light from the recording surface.

  Usually, the optical pickup device includes an objective lens, and guides the light emitted from the light source to the recording surface of the optical disc and guides the return light reflected by the recording surface to a predetermined light receiving position, which is disposed at the light receiving position. Lens driving device for driving the optical detector and the objective lens in the optical axis direction (hereinafter also referred to as “focus direction”) and the direction orthogonal to the tangential direction of the track (hereinafter also referred to as “tracking direction”) Etc. From the photodetector, a signal including not only reproduction information of data recorded on the recording surface but also information (servo information) necessary for position control of the objective lens is output.

  By the way, information is recorded on the optical disc by the lengths and combinations of marks and spaces having different reflectivities.

  Therefore, in the optical disk apparatus, a mark and a space of a target length are formed on the optical disk at the time of recording, and a test writing area called PCA (Power Calibration Area) is set in advance before recording information. Trial writing is performed to obtain the optimum recording power. This process is called an OPC (Optimum Power Control) process.

  In Patent Document 1, test recording is performed in a specified test recording area on an optical information recording medium while recording power is sequentially changed, the test recorded area is reproduced, and the reproduced signal is evaluated. Prior to the operation, there is disclosed an optimum recording power setting method for an optical information recording medium, which is characterized by irradiating and scanning all or a part of a test recording area with light whose intensity is modulated in a pulse shape.

  Patent Document 2 discloses an optical disk recording method in which a signal is recorded by irradiating an optical beam with an optical beam. The optical disk is irradiated with a light beam having a changed power level, the signal is recorded, and the signal is reproduced and modulated. Measure the degree of power, determine the target power level related to the target degree of modulation from the degree of modulation, record the signal by irradiating the optical disk with a light beam with a power level within the specified range from the target power level, and reproduce and modulate the signal The power level is determined by approximating the relationship between the power level of the predetermined range and the product of the power level of the predetermined range and the modulation degree by a linear function and irradiating the optical disk with the light beam of the power level. An optical disc recording method characterized by recording the above is disclosed.

  In Patent Document 3, in an optical disk recording method for recording information by gradually increasing the rotational speed of the optical disk from the inner circumference side to the outer circumference side, the recording operation is temporarily stopped when the rotation speed of the optical disk is switched. Then, the β value at this point is measured, the measured β value is compared with the target β value, the β value is corrected, and the recording power of the laser beam is adjusted in accordance with the correction of the β value to obtain information. A recording power control method characterized in that recording is performed is disclosed.

JP 2006-85879 A JP-A-2005-149538 JP 2005-92950 A

  Incidentally, in recent years, the density of optical discs has been increasing. Along with this, a further increase in writing speed is expected. However, as the density and the speed increase, the margin of the appropriate value of the recording power becomes narrow, and the recording power obtained by the OPC process may not necessarily be an appropriate recording power.

  The present invention has been made under such circumstances, and a first object thereof is to provide a recording power correction method capable of correcting the recording power when recording information on an optical disk to an appropriate recording power. It is in.

  A second object of the present invention is to provide a recording method capable of recording on an optical disc with stable recording quality.

  A third object of the present invention is a program that can be executed by a control computer of an optical disc apparatus and can correct the recording power when recording information on the optical disc to an appropriate recording power, and the program is recorded. Is to provide a recorded recording medium.

  A fourth object of the present invention is to provide an optical disc apparatus capable of recording on an optical disc with stable recording quality.

  A fifth object of the present invention is to provide an information processing apparatus capable of performing stable access to an optical disc.

  A sixth object of the present invention is to provide an optical disc capable of recording information with stable recording quality.

  The present invention, from a first viewpoint, is a recording power correction method for correcting recording power when recording information on an optical disc having a plurality of tracks on which information can be recorded. Evaluation information that is performed on continuous tracks and that includes a plurality of continuous tracks including boundaries between recorded and unrecorded tracks in the plurality of tracks as an evaluation region, and that depends on recording power by reflected light from the evaluation region For each track; and a step for correcting the recording power when information is recorded on the recorded track from the evaluation information for each track.

  According to this, when recording on an optical disc is performed on continuous tracks, a plurality of continuous tracks including boundaries between recorded tracks and unrecorded tracks in a plurality of tracks are set as an evaluation region, and from the evaluation region Evaluation information depending on the recording power is obtained for each track by the reflected light. Then, the recording power when information is recorded on the recorded track is corrected from the evaluation information for each track. That is, the recording power is corrected using information from a plurality of continuous tracks near the boundary between the recorded track and the unrecorded track. Therefore, it is possible to correct the recording power when recording information on the optical disc to an appropriate recording power.

  From a second point of view, the present invention is a recording method for recording information on an optical disc having a plurality of tracks on which information can be recorded, using the recording power corrected by the recording power correction method of the present invention. A recording method including a step of recording information.

  According to this, since the recording power corrected by the recording power correction method of the present invention is used, it becomes possible to perform recording on the optical disc with stable recording quality.

  From a third aspect, the present invention is a program used in an optical disc apparatus capable of recording information on an optical disc having a plurality of tracks on which information can be recorded, wherein recording on the optical disc is a continuous track. A procedure in which a plurality of continuous tracks including boundaries between recorded tracks and unrecorded tracks in the plurality of tracks are used as the evaluation region; depending on the recording power due to the reflected light from the evaluation region A program for causing a control computer of the optical disc apparatus to execute a procedure for obtaining evaluation information for each track; and a procedure for correcting recording power when information is recorded on the recorded track from the evaluation information for each track. It is.

  According to this, when the program of the present invention is loaded into a predetermined memory and the start address is set in the program counter, the control computer of the optical disc apparatus performs the recording on the optical disc continuously. In this case, a plurality of continuous tracks including the boundary between the recorded track and the unrecorded track in a plurality of tracks are set as an evaluation region, and evaluation information depending on the recording power is obtained for each track by reflected light from the evaluation region, From the evaluation information for each track, the recording power when information is recorded on the recorded track is corrected. That is, the recording power is corrected using information from a plurality of continuous tracks near the boundary between the recorded track and the unrecorded track. Therefore, it is possible to correct the recording power when recording information on the optical disc to an appropriate recording power.

  From the fourth viewpoint, the present invention is a computer-readable recording medium on which the program of the present invention is recorded.

  According to this, since the program of the present invention is recorded, the recording power when information is recorded on the optical disc can be corrected to an appropriate recording power by causing the computer to execute the program.

  From a fifth aspect, the present invention is an optical disc apparatus capable of recording information on an optical disc having a plurality of tracks on which information can be recorded, and irradiates the optical disc with light and receives reflected light. An optical pickup device; and a plurality of continuous tracks including boundaries between recorded and unrecorded tracks in the plurality of tracks when the recording on the optical disc is performed on the continuous tracks, and the optical pickup Using the photoelectric conversion signal of the reflected light from the evaluation area obtained through the apparatus, the evaluation information depending on the recording power is obtained for each track, and the information on the recorded track is obtained from the evaluation information for each track. And a processing device that corrects recording power when recording is performed.

  According to this, when the recording on the optical disc is performed on the continuous track, the processing device removes from the evaluation area composed of the continuous plural tracks including the boundary between the recorded track and the unrecorded track in the plural tracks. Using the photoelectric conversion signal of the reflected light, evaluation information depending on the recording power is obtained for each track, and the recording power when information is recorded on the recorded track is corrected from the evaluation information for each track. That is, the recording power is corrected using information from a plurality of continuous tracks near the boundary between the recorded track and the unrecorded track. Therefore, it is possible to perform recording on the optical disc with stable recording quality.

  From a sixth aspect, the present invention is an information processing apparatus comprising: the optical disc device of the present invention; and a control device that controls the optical disc device.

  According to this, since the optical disk device of the present invention is provided, as a result, stable access to the optical disk can be performed.

  According to a seventh aspect of the present invention, in an optical disc having a plurality of tracks on which information can be recorded, when information is recorded on successive tracks of the plurality of tracks, the recorded tracks and unrecorded tracks are recorded. The optical disc is characterized in that information dependent on recording power obtained from a plurality of continuous tracks including boundaries is preformatted for each of a plurality of different recording powers including appropriate recording power.

  According to this, the optical disc apparatus in which the optical disc of the present invention is set can easily correct the recording power when recording information to an appropriate recording power, and as a result, information can be recorded with stable recording quality. It becomes possible to do.

  Hereinafter, an embodiment of the present invention will be described with reference to FIGS. FIG. 1 shows a schematic configuration of an optical disc apparatus 20 according to an embodiment of the present invention.

  An optical disk device 20 shown in FIG. 1 includes a spindle motor 22 that rotates and drives an optical disk 15 according to an embodiment of the present invention, an optical pickup device 23, a seek motor 21 that drives the optical pickup device 23 in a sledge direction, and a laser. A control circuit 24, an encoder 25, a drive control circuit 26, a reproduction signal processing circuit 28, a buffer RAM 34, a buffer manager 37, an interface 38, a flash memory 39, a CPU 40, a RAM 41, and the like are provided. Note that the arrows in FIG. 1 indicate the flow of typical signals and information, and do not represent the entire connection relationship of each block.

  The optical disc 15 is a write-once disc (BD-R: Blu-ray Disc Recordable) that has a recording layer mainly composed of an oxide of bismuth (Bi) and conforms to the standard of the blue ray disc. A spiral groove (groove) is formed on the optical disk 15. Information is recorded in the groove. That is, the groove is a so-called information track. This information track is divided into a plurality of tracks that are continuous in the spiral direction, and each track is assigned a track number that continuously increases from the inner circumference side of the disc toward the outer circumference side.

<Recording strategy information>
The recording strategy information includes various parameters that define the light emission waveform according to the mark length nT (n = 2 to 9, T is the period of the recording channel clock). Here, as an example, as shown in FIGS. 2 (A) to 4 (B), a recording strategy employed in an 8 × DVD-R or a 16 × DVD + R is used. 2A shows a light emission waveform when the 2T mark is formed, FIG. 2B shows a light emission waveform when the 3T mark is formed, and FIG. 2C shows the light emission waveform. Shows a light emission waveform when a 4T mark is formed. 3A shows a light emission waveform when a 5T mark is formed, FIG. 3B shows a light emission waveform when a 6T mark is formed, and FIG. 3C shows the light emission waveform. Shows a light emission waveform when a 7T mark is formed. Further, FIG. 4A shows a light emission waveform when the 8T mark is formed, and FIG. 4B shows a light emission waveform when the 9T mark is formed.

  Parameters (Ttop, dTop, Tlp, dTlp, dTs) that define the pulse width of the light emission waveform can be set uniquely for each of the 2T to 9T marks. An example of specific values of each parameter is shown in FIG.

  The irradiation power is set to any one of Pw (recording power or recording level), Pm (intermediate power or intermediate level), Ps (space power or space level), or Pb (base power or base level). Is done. These are in a relationship of Pw> Pm> Ps> Pb. These ratios are generally fixed, but can be set individually. It is not preferable to set these individually according to the mark length because the power setting becomes complicated.

<Evaluation of optical disc>
The optical disk 15 was evaluated by a method based on the international standard for BD-R, except for the recording strategy. The writing speed was quadruple speed, and information was recorded using 2L, 3T,..., 9T marks and spaces with RLL (1, 7). For recording and signal measurement after recording, ODU1000 (manufactured by Pulstec), which is a commercially available recording signal evaluation apparatus for BD-R, was used.

  Pm / Pw = 0.82, Ps / Pw = 0.18, Pb = 0.1 mW, information is recorded on 11 consecutive tracks, and the reflectance and jitter of the center track (sixth track) are measured. did. The measurement results are shown in FIG. R8H in FIG. 6 is the reflectance of the 8T space portion. According to the BD-R standard specifications, the reflectance R8H is set to 11 to 24%, and the jitter is set to 6.5% or less. The optical disk 15 sufficiently satisfies the standards for both the reflectance R8H and the jitter in the vicinity of 7.8 mW which is the optimum recording power.

  By the way, the relationship between the reflectivity R8H and Pw at the center track when recording on 11 tracks continuously, and the relationship between the reflectivity R8H and Pw at this track when recording only on one track are shown in FIG. 7. According to this, the reflectivity R8H at the center track when recording on 11 tracks continuously decreases as Pw increases. On the other hand, the reflectivity R8H on the track when recording is performed on only one track does not decrease so much even if Pw increases. This is presumably because the recording mark width increases due to an increase in Pw, which affects adjacent tracks.

  Therefore, when recording is performed on a plurality of continuous tracks, the reflectance R8H depends on Pw.

<Correction of recording power>
Information is recorded sequentially from the inner circumference side to the outer circumference side of the disc. Therefore, FIG. 8A shows the situation when recording is stopped at the track number N (hereinafter also referred to as “track N”). In FIG. 8A, the left side is the disc inner periphery side, and the right side is the disc outer periphery side. The reflectance at each track at this time is shown in FIG. The reflectance of the recorded track is R8H. The reflectance is standardized with a maximum value (here, Rgv (refer to the BD-R standard)) being 1. Then, f (n) in FIG. 8B is a function indicating the curve when the relationship between the reflectance and the track number n is fitted to the curve. In the vicinity of the track N, the reflectance changes greatly.

  For example, (1) recording condition 1: Pw = 7.8 mW (optimum recording power), (2) recording condition 2: Pw = 8.6 mW, (3) recording condition 3: Pw = 9.4 mW, continuous When recording was performed on 20 tracks, recording was stopped (N = 20), and reflectance was measured on tracks (N-5) to tracks (N + 5). The measurement results are shown in FIG.

Here, a function indicating the curve when the relationship between the measured reflectance (standardized value) and the track number n is fitted to the curve under the recording condition 1 is represented by f ₁ (n), When the relationship between the measured reflectance (standardized value) and the track number n is fitted to the curve under the recording condition _{2, the} function indicating the curve is represented by f ₂ (n), and the recording condition 3 In this case, let f ₃ (n) be a function indicating the curve when the relationship between the measured reflectance (normalized value) and the track number n is fitted to the curve. Each function is assumed to be a polynomial represented by a ₀ + a ₁ n + a ₂ n ² +.

In this case, the difference between the parameter specifying the function f ₁ (n) (here, a ₀ , a ₁ , a ₂ ,...) And the parameter specifying the function f ₂ (n) is the recording power. Is 10% over the optimum recording power, and the difference between the parameter for specifying the function f ₁ (n) and the parameter for specifying the function f ₃ (n) is the recording with the optimum recording power. It shows that the power is over 20%.

Therefore, when recording is performed with a certain recording power X, a function f _x (n) indicating the curve when the relationship between the measured reflectance (standardized value) and the track number n is fitted to the curve. Is obtained from the difference between the parameter for specifying the function f ₁ (n) and the parameter for specifying the function f _x (n).

  Then, the recording power can be set to an appropriate recording power by adjusting the driving current of the light source according to the shift amount with respect to the optimum recording power.

  Returning to FIG. 1, the optical pickup device 23 is a device for condensing light on the recording layer of the optical disc 15 and receiving reflected light from the optical disc 15. As shown in FIG. 10 as an example, the optical pickup device 23 includes a light source unit 51, a coupling lens 52, a polarizing beam splitter 54, a quarter wavelength plate 55, an objective lens 60, a condenser lens 58, and a photodetector. And a driving system AC for driving the objective lens 60, and the like.

  The light source unit 51 includes a semiconductor laser LD as a light source that emits laser light having a wavelength (here, about 404 nm) corresponding to the optical disk 15. In the present embodiment, the maximum intensity emission direction of the laser light emitted from the light source unit 51 is the + X direction. As an example, it is assumed that P-polarized light is emitted from the light source unit 51.

  A coupling lens 52 is disposed on the + X side of the light source unit 51, and the light emitted from the light source unit 51 is made to be substantially parallel light.

  The polarization beam splitter 54 is disposed on the + X side of the coupling lens 52. The polarization beam splitter 54 has a different reflectance depending on the polarization state of incident light. Here, for example, the polarization beam splitter 54 is set so that the reflectance with respect to the P-polarized light is small and the reflectance with respect to the S-polarized light is large. That is, most of the light emitted from the light source unit 51 can pass through the polarization beam splitter 54. A quarter wavelength plate 55 is disposed on the + X side of the polarization beam splitter 54.

  The quarter wavelength plate 55 gives an optical phase difference of a quarter wavelength to incident light. An objective lens 60 is disposed on the + X side of the quarter wavelength plate 55, and condenses the light that has passed through the quarter wavelength plate 55 on the recording layer.

  The detection lens 58 is disposed on the −Z side of the polarization beam splitter 54, and condenses the return light branched in the −Z direction by the polarization beam splitter 54 on the light receiving surface of the light receiver 59. The light receiver 59 includes a plurality of light receiving elements (or light receiving regions) for generating a signal (photoelectric conversion signal) optimal for detecting an RF signal, a wobble signal, a servo signal, and the like in the reproduction signal processing circuit 28. It is configured to include.

  The drive system AC includes a focusing actuator for minutely driving the objective lens 60 in the focus direction, which is the optical axis direction of the objective lens 60, and a tracking actuator for minutely driving the objective lens 60 in the tracking direction.

  Returning to FIG. 1, the reproduction signal processing circuit 28 is based on the output signal (a plurality of photoelectric conversion signals) of the light receiver PD, servo signals (focus error signal, track error signal, etc.), reflectance information, address information, synchronization Information and RF signals are acquired. The servo signal obtained here is output to the drive control circuit 26, the reflectance information and the address information are output to the CPU 40, and the synchronization signal is output to the encoder 25, the drive control circuit 26, and the like. Further, the reproduction signal processing circuit 28 performs a decoding process and an error detection process on the RF signal. When an error is detected, the reproduction signal processing circuit 28 performs an error correction process and then stores the reproduction data in the buffer RAM 34 via the buffer manager 37. Store. The address information included in the reproduction data is output to the CPU 40.

  Based on the track error signal from the reproduction signal processing circuit 28, the drive control circuit 26 generates a tracking actuator drive signal for correcting the displacement of the objective lens 60 in the tracking direction. Further, the drive control circuit 26 generates a drive signal for the focusing actuator AC for correcting the focus shift of the objective lens 60 based on the focus error signal from the reproduction signal processing circuit 28. The drive signals for the actuators generated here are output to the optical pickup device 23. Thereby, tracking control and focus control are performed. Furthermore, the drive control circuit 26 generates a drive signal for driving the seek motor 21 and a drive signal for driving the spindle motor 22 based on an instruction from the CPU 40. The drive signal of each motor is output to the seek motor 21 and the spindle motor 22, respectively.

  The buffer RAM 34 temporarily stores data to be recorded on the optical disk 15 (recording data), data reproduced from the optical disk 15 (reproduction data), and the like. Data input / output to / from the buffer RAM 34 is managed by a buffer manager 37.

  Based on an instruction from the CPU 40, the encoder 25 takes out the recording data stored in the buffer RAM 34 through the buffer manager 37, modulates the data, adds an error correction code, and the like, and outputs a write signal to the optical disc 15. Generate. The write signal generated here is output to the laser control circuit 24.

  The laser control circuit 24 controls the light emission power of the semiconductor laser LD. For example, at the time of recording, a drive signal for the semiconductor laser LD is generated by the laser control circuit 24 based on a write signal, a recording condition including a recording strategy, a light emission characteristic of the semiconductor laser LD, and the like.

  The interface 38 is a bidirectional communication interface with the host device 90 (for example, a personal computer) and conforms to standard interfaces such as ATAPI (AT Attachment Packet Interface), SCSI (Small Computer System Interface), and USB (Universal Serial Bus). is doing.

  The flash memory 39 stores various programs including a program according to an embodiment of the present invention described by a code readable by the CPU 40, recording conditions including a recording strategy, and various data such as light emission characteristics of the semiconductor laser LD. Has been.

  The CPU 40 controls the operation of each unit in accordance with the program stored in the flash memory 39 and saves data necessary for control in the RAM 41 and the buffer RAM 34.

<Recording process>
Next, processing (recording processing) in the optical disc device 20 when a recording request is received from the host device 90 will be described with reference to FIGS. The flowcharts of FIGS. 11 and 12 correspond to a series of processing algorithms executed by the CPU 40. When a recording command is received from the host device 90, the head address of a program (hereinafter referred to as “recording processing program”) corresponding to the flowcharts of FIGS. 11 and 12 stored in the flash memory 39 is set in the program counter of the CPU 40. The recording process starts.

  The optical disc 15 has a reflectance (standardized value) obtained from a plurality of continuous tracks including the boundary between the recorded track and the unrecorded track and a track number n when recorded on the continuous track. Information for specifying a function indicating the curve when the relationship is fitted to the curve (hereinafter also referred to as “function information” for convenience) is preformatted for each of a plurality of different recording powers including an appropriate recording power. . The function information is read when the optical disk 15 is loaded and stored in the RAM 41.

  Further, here, in order to verify the effect of correcting the recording power, as shown in FIG. 13 as an example, an optical disc for testing in which the optimum recording power gradually decreases as the distance from the center of rotation increases. 15 was used.

  In the first step S401, the drive control circuit 26 is instructed to rotate the optical disc 15 at a predetermined linear velocity (or angular velocity), and the reproduction signal processing circuit 28 is notified that a recording command has been received from the host device 90. .

  In the next step S403, an OPC process is performed to obtain an optimum recording power. Here, since the OPC process is performed using the PCA area provided on the inner peripheral side, the optimum recording power obtained by the OPC process is 8.8 mW.

  In the next step S405, a track number for correcting the recording power is obtained based on the recording command. Here, as an example, it is assumed that recording is performed on all tracks, and the recording power is corrected with tracks having distances from the rotation center of 24 mm, 30 mm, 40 mm, 50 mm, 55 mm, and 57 mm.

  In the next step S407, the track number for which the recording power is first corrected is set to the track number (hereinafter abbreviated as “interrupt track number”) N of the track where writing is interrupted. Here, the track number of the track at a position where the distance from the rotation center is 24 mm is set.

  In the next step S409, writing is permitted. Thereby, writing to the optical disc 15 is performed via the encoder 25, the laser control circuit 24, the optical pickup device 23, and the like.

  In the next step S411, it is determined whether or not the track number to be written is equal to the interrupted track number N. If the track number to be written is not equal to the interrupted track number N, the determination here is denied and the determination is made again after a predetermined time has elapsed. On the other hand, if the track number to be written is equal to the interrupted track number N, the determination here is affirmed and the process proceeds to step S413.

  In step S413, an interruption of writing is instructed.

  In the next step S415, the reflectance in the track (N-4) to the track (N + 4) is obtained via the reproduction signal processing circuit 28. Then, the maximum value (here, the value at the track (N + 4)) is normalized as 1.

  In the next step S417, a function indicating the curve when the relationship between the normalized reflectance and the track number n is fitted to the curve is obtained.

  In the next step S419, the function information specifying the function obtained in step S417 is compared with the function information stored in the RAM 41 to obtain the recording power deviation information.

  In the next step S421, a recording power correction is instructed based on the recording power deviation information. The relationship between the recording power deviation information and the LD driving current is obtained in advance and stored in the flash memory 39.

  In the next step S423, resumption of writing is instructed.

  In the next step S501, it is determined whether there is a track whose recording power is to be corrected next. If there is a track whose recording power is to be corrected next, the determination here is affirmed and the process proceeds to step S503.

  In step S503, the track number for correcting the recording power next is set as the interrupted track number N. Here, the track number of the track at a position where the distance from the rotation center is 30 mm is set. Then, the process returns to step S411.

  Thereafter, the processes in steps S411 to S503 are repeated until the determination in step S501 is denied.

  Next, if there is no track for correcting the recording power, the determination in step S501 is denied, and the process proceeds to step S505.

  In this step S505, it is determined whether or not all the recording data instructed from the host device 90 has been written. If all of the recording data instructed from the host device 90 has not been written, the determination here is denied and the determination is made again after a predetermined time has elapsed. If all of the recording data instructed from the higher-level device 90 has been written, the determination here is affirmed and the process proceeds to step S507.

  In step S507, the host device 90 is notified of the completion of recording. Then, the recording process ends.

  The recording power in this recording process is shown in FIG. By correcting the recording power as described above, writing can be performed with a recording power close to the optimum recording power in all tracks. As an example, as shown in FIG. 15, a jitter of 6.5% or less could be realized in all tracks.

  As is clear from the above description, in the optical disc device 20 according to the present embodiment, a processing device is configured by the CPU 40 and a program executed by the CPU 40. It should be noted that at least a part of the processing according to the program by the CPU 40 may be configured by hardware, or all may be configured by hardware.

  In the present embodiment, the program according to the present invention is executed by the programs corresponding to FIGS. 11 and 12 among the programs recorded in the flash memory 39 as the recording medium.

  In the recording process, the recording power correction method and the recording method according to the present invention are carried out.

  As described above, according to the optical disc apparatus 20 according to the present embodiment, when recording on the optical disc 15 is performed on continuous tracks, continuous recording including boundaries between recorded tracks and unrecorded tracks in a plurality of tracks is performed. The plurality of tracks are used as an evaluation area, and reflectivity (evaluation information depending on recording power) is obtained for each track by reflected light from the evaluation area. Then, information on the deviation of the recording power from the appropriate recording power when information is recorded on the recorded track is obtained from the reflectance for each track, and the recording power is corrected based on the information on the deviation. . Here, the recording power is corrected using information from multiple continuous tracks near the boundary between the recorded and unrecorded tracks, so the recording power when recording information on the optical disk is corrected to an appropriate recording power. It becomes possible to do.

  In the present embodiment, nine tracks from track (N-4) to track (N + 4) are used as the evaluation area. Thereby, the dependence of the reflectance on the track number can be obtained with high accuracy.

  Further, in the present embodiment, the measured reflectances are normalized with the maximum value among them being 1. Thereby, the influence of the dispersion | variation in a measured value can be reduced. Furthermore, the processing algorithm can be simplified and generalized.

  In this embodiment, a function indicating the curve when the relationship between the normalized reflectance and the track number n is fitted to the curve is obtained, and the function information for specifying the function is stored in the RAM 41. The deviation of the recording power is obtained by comparing with the function information. Thereby, the recording power deviation information can be quickly obtained.

  In the present embodiment, since the function information for each of a plurality of different recording powers including appropriate recording power is preformatted on the optical disc 15, the recording power can be corrected efficiently.

  In the above-described embodiment, the case where the recording power is corrected with the tracks whose distance from the rotation center is 24 mm, 30 mm, 40 mm, 50 mm, 55 mm, and 57 mm has been described, but the present invention is not limited to this. For example, the recording power may be corrected every few mm. Further, the correction timing may be determined according to the type of the optical disk.

  In the above-described embodiment, the case where the function information for each of a plurality of different recording powers including appropriate recording power is preformatted on the optical disc 15 is described. Function information for different recording powers may be stored in the flash memory 39.

  Moreover, although the said embodiment demonstrated the case where 9 track | trucks (N-4)-track (N + 4) were made into an evaluation area | region, it is not limited to this. For example, the number of tracks in the evaluation area may be changed according to the characteristics of the optical disk. Also, the number of tracks in the evaluation area may be changed according to the required accuracy. In short, it is only necessary to obtain the dependency of the reflectance on the track number.

  Moreover, although the said embodiment demonstrated the case where each measured reflectance was normalized by making the maximum value among them into 1, it is not limited to this. In short, it is only necessary to obtain the dependency of the reflectance on the track number.

  In the above embodiment, a function indicating the curve when the relationship between the normalized reflectance and the track number n is fitted to the curve is obtained, and the function information for specifying the function is stored in the RAM 41. Although the description has been given of the case where the recording power deviation information is obtained by comparing with the function information, the present invention is not limited to this. For example, when the reflectance (target value of reflectance) when the evaluation area is recorded with the optimum recording power is preformatted on the optical disc, the measured value and the target value of the reflectance in each track of the evaluation area The recording power deviation information may be obtained from the difference or the average value of the differences.

  In the above embodiment, instead of the reflectance R8H, the average reflectance of R8H and R8L, the degree of modulation, asymmetry, the amplitude of the wobble signal, and the SN ratio of the wobble signal may be measured. By approximating these measured values as a function of the track number n, the recording power correction accuracy can be improved as compared with the conventional technique.

  By the way, in BD-R, the recording speed has been increased, and quadruple speed recording has been put to practical use. However, in high-speed recording at quadruple speed or higher, the demand for recording power accuracy is further increased. In the above embodiment, it is possible to perform recording with an appropriate recording power even at a speed of 4 × or higher.

  Moreover, running OPC is performed in CD-R. This is a method of adjusting the recording power based on the return light (reflected light) at the time of recording, but is limited to the case of recording on a dye material using a simple recording strategy. Recent optical discs compatible with high-density and high-speed recording employ a complicated recording strategy, so that it is difficult to adjust to an appropriate recording power in running OPC.

  In the above-described embodiment, the case where the optical disk 15 is the BD-R has been described. However, the present invention is not limited to this. It may be. Also, CD-R (CD-Recordable), CD-RW (CD-Rewritable), DVD-R (DVD-Recordable), DVD + R (DVD + Recordable), DVD-RW (DVD-Rewritable), DVD + RW (DVD + Rewriteable) Also good. However, in these cases, it is necessary to replace the light source with a corresponding light source.

  Moreover, although the said embodiment demonstrated the case where an optical disk had one recording layer, it is not restricted to this, The optical disk may have a some recording layer.

  In the above embodiment, the program according to the present invention is recorded in the flash memory 39, but is recorded in another recording medium (CD, magneto-optical disk, DVD, memory card, USB memory, flexible disk, etc.). May be. In this case, the program according to the present invention is loaded into the flash memory 39 via the playback device (or dedicated interface) corresponding to each recording medium. Further, the program according to the present invention may be transferred to the flash memory 39 via a network (LAN, intranet, Internet, etc.). In short, the program according to the present invention may be loaded into the flash memory 39.

  In the above embodiment, the case where the optical pickup device includes one semiconductor laser has been described. However, the present invention is not limited thereto, and for example, a plurality of semiconductor lasers that emit light having different wavelengths may be included. That is, the optical disk apparatus may be an optical disk apparatus that supports a plurality of types of optical disks that conform to different standards.

《Information processing device》
Next, an information processing apparatus according to an embodiment of the present invention will be described with reference to FIG.

  The information processing apparatus 10 includes a main control device 92, the optical disk device 20, a hard disk device (HDD) 94, an input device 95, a display device 96, a drive interface 97, and the like.

  The HDD 94 includes a hard disk 94b and a drive device 94a for driving the hard disk 94b.

  The display device 96 includes a display unit (not shown) using, for example, a CRT, a liquid crystal display (LCD), a plasma display panel (PDP), and the like, and displays various information instructed from the main control device 92.

  The input device 95 includes at least one input medium (not shown) of, for example, a keyboard, a mouse, a tablet, a light pen, a touch panel, and the like, and notifies the main control device 92 of various information input by the user. Note that information from the input medium may be input in a wireless manner. In addition, an example in which the display device 96 and the input device 95 are integrated includes an LCD with a touch panel.

  The drive interface 97 is a bidirectional interface between the main control device 92, the optical disc device 20, and the HDD 94, and conforms to the same standard interface as the interface 38 of the optical disc device 20.

  In the information processing apparatus 10 configured as described above, when a user inputs a recording request for the optical disc 15 via the input device 95, the main control device 92 transmits a recording command and recording data to the optical disc device 20. .

  When receiving the recording command, the optical disc apparatus 20 performs the recording process.

  The main controller 92 displays the recording result of the optical disc device 20 on the display unit of the display device 96.

  As described above, according to the information processing apparatus 10 according to the present embodiment, since the optical disc apparatus 20 that can perform recording with stable recording quality is provided on the optical disc, as a result, the optical disc is stable with respect to the optical disc. Access can be made.

  In the information processing apparatus 10, the optical disk device 20 may be a so-called built-in type or a so-called external type.

  As described above, the recording power correction method of the present invention is suitable for correcting the recording power when recording information on the optical disc to an appropriate recording power. The recording method of the present invention is suitable for recording on an optical disc with stable recording quality. The program and the recording medium of the present invention are suitable for causing the control computer of the optical disk apparatus to correct the recording power when recording information on the optical disk to an appropriate recording power. Moreover, the optical disc apparatus of the present invention is suitable for recording on an optical disc with stable recording quality. The information processing apparatus according to the present invention is suitable for performing stable access to the optical disc. The optical disc of the present invention is suitable for recording information with stable recording quality.

1 is a block diagram showing a schematic configuration of an optical disc apparatus according to an embodiment of the present invention. FIGS. 2A to 2C are diagrams (part 1) for explaining the recording strategy. FIGS. 3A to 3C are diagrams (part 2) for explaining the recording strategy, respectively. FIG. 4A and FIG. 4B are diagrams (part 3) for explaining the recording strategy, respectively. It is a figure for demonstrating the specific example of each parameter in FIG. 2 (A)-FIG. 4 (B). It is a figure for demonstrating the relationship between reflectance R8H when recording on a continuous track | truck, jitter, and recording power. It is a figure for demonstrating the relationship between reflectivity R8H and recording power when recording on a continuous track and when recording on only one track. FIG. 8A is a diagram for explaining an evaluation area including a plurality of continuous tracks including a boundary between a recorded track and an unrecorded track, and FIG. 8B is a diagram for explaining reflectance in the evaluation area. FIG. It is a figure for demonstrating the difference in the reflectance in the evaluation area | region by recording conditions. It is a figure for demonstrating the optical pick-up apparatus in FIG. 5 is a flowchart (part 1) for describing a recording process in the optical disc apparatus. 12 is a flowchart (part 2) for describing a recording process in the optical disc apparatus. It is a figure for demonstrating the optical disk for a test used by the recording process. It is a figure for demonstrating the recording power correct | amended by the recording process. It is a figure for demonstrating the jitter after a recording process. It is a block diagram which shows schematic structure of the information processing apparatus which concerns on one Embodiment of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Information processing apparatus, 15 ... Optical disk, 20 ... Optical disk apparatus, 23 ... Optical pick-up apparatus, 39 ... Flash memory (recording medium), 40 ... CPU (processing apparatus), 92 ... Main control apparatus (control apparatus).

Claims (13)

A recording power correction method for correcting recording power when recording information on an optical disc having a plurality of tracks on which information can be recorded,
Recording on the optical disc is performed on continuous tracks,
Obtaining a plurality of continuous tracks including boundaries between recorded and unrecorded tracks in the plurality of tracks as an evaluation area, and obtaining evaluation information depending on recording power for each track by reflected light from the evaluation area;
Correcting the recording power when information is recorded on the recorded track from the evaluation information for each track.   The recording power correction method according to claim 1, wherein the evaluation area includes at least five recorded tracks and at least four unrecorded tracks. The step of correcting the recording power includes:
Obtaining a function that fits the evaluation information for each track;
Obtaining information relating to a difference between the function and a function obtained when recording with an appropriate recording power obtained in advance;
The recording power correction method according to claim 1, further comprising: correcting the recording power based on the information regarding the difference.   The recording power correction method according to claim 1, wherein the evaluation information is standardized.   The recording power correction according to claim 1, wherein the evaluation information is any one of reflectance, modulation degree, asymmetry, amplitude of a wobble signal, and an SN ratio of the wobble signal. Method. A recording method for recording information on an optical disc having a plurality of tracks capable of recording information,
A recording method comprising a step of recording information with a recording power corrected by the recording power correction method according to claim 1. A program used in an optical disc apparatus capable of recording information on an optical disc having a plurality of tracks capable of recording information,
When recording on the optical disc is performed on continuous tracks,
A procedure in which a plurality of continuous tracks including a boundary between a recorded track and an unrecorded track in the plurality of tracks are set as an evaluation area;
A procedure for obtaining, for each track, evaluation information depending on recording power by reflected light from the evaluation area;
A program for causing the control computer of the optical disc apparatus to execute a procedure for correcting recording power when information is recorded on the recorded track from the evaluation information for each track. As a procedure for correcting the recording power,
Obtaining a function that fits the evaluation information for each track;
A procedure for obtaining information relating to a difference between the function and a function when the recording is performed with an appropriate recording power obtained in advance;
8. The program according to claim 7, further comprising: causing the control computer to execute a procedure for correcting a recording power based on the information relating to the difference.   A computer-readable recording medium on which the program according to claim 7 or 8 is recorded. An optical disc apparatus capable of recording information on an optical disc having a plurality of tracks capable of recording information,
An optical pickup device for irradiating the optical disc with light and receiving reflected light;
When recording on the optical disk is performed on continuous tracks, a plurality of continuous tracks including boundaries between the recorded tracks and the unrecorded tracks in the plurality of tracks are set as an evaluation area, and obtained through the optical pickup device. Using the photoelectric conversion signal of the reflected light from the evaluation area, the evaluation information depending on the recording power is obtained for each track, and the information when the information is recorded on the recorded track from the evaluation information for each track And a processing device for correcting the recording power.   The processing device obtains a function that fits the evaluation information for each track, and calculates a recording power based on information on a difference between the function and a function that is recorded in advance with an appropriate recording power. The optical disk apparatus according to claim 10, wherein correction is performed. An optical disc device according to claim 10 or 11, and
An information processing apparatus comprising: a control device that controls the optical disk device. In an optical disc having a plurality of tracks on which information can be recorded,
When information is recorded on successive tracks of the plurality of tracks, the information depending on the recording power obtained from a plurality of continuous tracks including the boundary between the recorded track and the unrecorded track includes a plurality of information including appropriate recording power. An optical disc characterized by being preformatted for each of different recording powers.

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