JP2008041139A - Disk recording/reproducing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a disk recording/reproducing device performing an adjustment process for optimally adjusting optical beam recording power in consideration of vibrations temporarily applied to an optical disk. <P>SOLUTION: An RFRP signal generation part 14 generates an RFRP signal on the basis of an RF signal generated by an RF signal generation part 12 when a pickup 11 reproduces data recorded in the PCA area of an optical disk 1a. A swing width detection part 15 calculates average amplitude of the RFRP signal in a predetermined time, and a difference (swing width) between maximum amplitude and minimum amplitude of the RFRP signal in the predetermined time to calculate ratio of the swing width to the average amplitude. A control part 10 determines, when the ratio of the swing width to the average amplitude is larger than a predetermined threshold value, that the optical disk 1a temporarily receives abnormal vibrations during execution of OPC processing. An OPC processing part 13 calculates β value based on the RF signal a plurality of times, and performs OPC processing for deciding optimal recording power on the basis of an average value thereof. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a disk recording / reproducing apparatus for recording data by irradiating a light beam onto a disk-shaped recording medium and reproducing the recorded data.

  An optical disc apparatus for writing information on an optical disc such as a DVD-R, a DVD-RW, a DVD + RW, a DVD-ROM, a CD-R, and a CD-RW using a laser beam as a light beam, for example, writes information on the optical disc. In order to determine the optimum recording power, OPC (Optimum Power Control) processing is performed. The OPC process is obtained by writing a test pattern to a test area provided in advance on an optical disc while changing the recording power stepwise, and reading and reproducing the written test pattern. This is a process for determining an optimum recording power based on an RF (Radio Frequency) signal. By writing to the optical disc with the optimum recording power determined by such OPC processing, variations in recording sensitivity between different optical discs, differences in characteristics between the optical disc and the optical pickup of the optical disc apparatus, ambient temperature, etc. Thus, the writing process can be performed under the optimum conditions in consideration of the above, and the reliability of the information written on the optical disk can be ensured.

  Patent Document 1 discloses an OPC that determines an optimum recording power based on a β value calculated from a maximum value and a minimum value of an RF signal obtained by reproducing a test pattern written in a test area on an optical disc. An optical disc apparatus configured to perform processing is disclosed. Further, in Patent Document 2, a randomly generated test pattern is written in a test area on an optical disc, and the test signal is reproduced based on amplitude information, jitter value, or data error rate of an RF signal obtained by reproducing the test pattern. An optical disc apparatus configured to perform OPC processing for determining optimum recording power is disclosed.

Further, the optical disc apparatus disclosed in Patent Document 1 has a configuration in which running OPC processing is performed in which the recording power is sequentially adjusted by the above-described OPC processing while performing information writing processing on the optical disc. By performing the running OPC process, it is possible to perform a writing process with an optimum recording power corresponding to various changes in writing conditions that occur sequentially when information is written on the optical disk.
JP 2003-178450 A JP 2004-199746 A

  Here, the optical disk may be subjected to vibrations based on shocks and vibrations externally received by the optical disk apparatus, and abnormal vibrations that are temporarily generated, such as vibrations received from the optical disk apparatus when information is written. However, as described above, the running OPC process enables a writing process that takes into account changes in various writing conditions that occur when information is written on the optical disk, but can handle temporary vibrations received from the optical disk apparatus. Often not. Therefore, even when the RF signal in the OPC process includes a vibration based on the vibration received from the optical disk device, only the same processing as when no vibration is received from the optical disk device is performed. Therefore, the optimum recording power obtained by the running OPC process is determined based on the RF signal including the vibration based on the vibration temporarily received by the optical disc, and the specified recording power is not optimum. Has the problem that there may be.

  The present invention has been made in view of such circumstances, and the object of the present invention is not only the characteristics of the optical disk, the characteristics of the optical disk and the disk recording / reproducing apparatus, the ambient temperature, etc., but also the optical disk is subjected temporarily. An object of the present invention is to provide a disc recording / reproducing apparatus capable of performing a write process with a more optimal recording power by performing an adjustment process of a recording power of a light beam in consideration of vibration.

  Another object of the present invention is to perform sampling processing to reduce the influence when the fluctuation temporarily added to the reproduction signal due to the vibration received temporarily by the optical disc is reduced, thereby reducing the influence of the fluctuation. An object of the present invention is to provide a disk recording / reproducing apparatus capable of determining a more optimal recording power by adjusting processing based on a reproduction signal.

  A disc recording / reproducing apparatus according to the present invention comprises a recording means for recording data by irradiating a light beam onto a disc-shaped recording medium, and a reproducing means for reproducing the data recorded by the recording means and outputting a reproduction signal. In the disk recording / reproducing apparatus, comprising: adjusting means for performing adjustment processing for optimally adjusting the recording power of the light beam when data is recorded based on the state of the reproduction signal output by the reproducing means. A difference calculating means for calculating a difference between a maximum value and a minimum value within a predetermined time of the reproduction signal output by the means; an amplitude calculating means for calculating an average value of the amplitude of the reproduction signal within the predetermined time; and the amplitude calculation A ratio calculating unit that calculates a ratio of the difference calculated by the difference calculating unit with respect to the average value of the amplitude calculated by the unit, and the adjusting unit includes: Characterized in that are configured to perform the adjustment processing according to the proportion that issued.

  According to the present invention, the recording power of the light beam when recording data is recorded on the basis of the state of the reproduction signal that is reproduced and output by the disk recording / reproducing apparatus on the data recorded on the disk-shaped recording medium. When performing the adjustment process for optimal adjustment, the difference between the maximum value and the minimum value of the reproduction signal within a predetermined time and the average value of the amplitude of the reproduction signal within the predetermined time are calculated, and the calculated average value of the amplitude is Calculate the difference ratio. Therefore, since the recording power adjustment process is performed based on the fluctuation state in the reproduction signal indicated by the ratio of the difference to the average value of the reproduction signal amplitude, the fluctuation state temporarily added to the reproduction signal is taken into consideration. It is possible to determine a more optimal recording power by the adjustment process.

  In the disk recording / reproducing apparatus according to the present invention, the adjusting means performs an adjustment process for adjusting the recording power of the light beam based on a value obtained by sampling the reproduction signal at each predetermined time, When the ratio calculated by the ratio calculation unit is larger than a preset threshold value, the adjustment process is performed based on an average value of a plurality of values obtained by sampling the reproduction signal a plurality of times at the predetermined time. It is configured as described above.

  According to the present invention, when the disc recording / reproducing apparatus has a ratio of the difference between the maximum value and the minimum value of the reproduction signal within the predetermined time with respect to the average value of the amplitude of the reproduction signal within the predetermined time being larger than the predetermined threshold value. The optical beam recording power is adjusted based on the average value of a plurality of values obtained by sampling the reproduction signal a plurality of times at the predetermined time. Therefore, the adjustment that can reduce the influence of the fluctuation temporarily added to the reproduction signal by the average value in the sampling of a plurality of times and determine the optimum recording power by the adjustment processing based on such reproduction signal. Perform processing.

  In the disk recording / reproducing apparatus according to the present invention, the adjusting means performs an adjustment process for adjusting the recording power of the light beam based on a value obtained by sampling the reproduction signal at each predetermined time, When the ratio calculated by the ratio calculation unit is greater than a preset threshold, the adjustment process is performed based on a value obtained by sampling the reproduction signal every time longer than the predetermined time. It is characterized by being.

  According to the present invention, when the ratio of the difference with respect to the calculated average value of the reproduction signal is larger than the predetermined threshold, the disk recording / reproducing apparatus outputs the reproduction signal every time longer than the predetermined time for sampling the reproduction signal. The recording power of the light beam is adjusted based on the value obtained by sampling. Therefore, by extending the sampling time, the influence of the vibration temporarily added to the reproduction signal due to the vibration temporarily received by the recording medium is reduced, and the optimum recording can be performed by the adjustment processing based on the reproduction signal. Adjustment processing capable of determining the power for use is performed.

  In the present invention, the disc recording / reproducing apparatus reproduces the data recorded on the disc-shaped recording medium and outputs the maximum value of the reproduced signal within the predetermined time with respect to the average value of the reproduced signal within the predetermined time. And the adjustment process of the recording power of the light beam is performed based on the ratio of the difference between the minimum values. Therefore, it is possible to perform an adjustment process in consideration of the vibration temporarily added to the reproduction signal due to various vibrations received from the recording medium. Therefore, a writing process with a more optimal recording power determined by such an adjustment process can be performed, and the reliability of the information written on the recording medium can be ensured more stably.

  In the present invention, when the disc recording / reproducing apparatus has a ratio of the difference between the maximum value and the minimum value of the reproduction signal within the predetermined time with respect to the average value of the amplitude of the reproduction signal within the predetermined time, that is, The recording power of the light beam based on the average value of multiple values obtained by sampling the reproduction signal multiple times when the fluctuation temporarily added to the reproduction signal due to the vibration received temporarily by the recording medium is large The adjustment process is performed. As a result, the influence of the fluctuation temporarily added to the reproduction signal can be reduced by a plurality of sampling values, and a more optimum recording power can be obtained by the adjustment process based on the reproduction signal in which the influence of the fluctuation is reduced. Can be determined.

  In the present invention, when the disc recording / reproducing apparatus has a ratio of the difference between the maximum value and the minimum value of the reproduction signal within the predetermined time with respect to the average value of the amplitude of the reproduction signal within the predetermined time, that is, When the fluctuation temporarily added to the reproduction signal due to the vibration received temporarily by the recording medium is large, the recording power of the light beam is determined based on the value obtained by sampling the reproduction signal by extending the sampling time. Perform the adjustment process. As a result, the influence of the fluctuation temporarily added to the reproduction signal can be reduced by a long sampling time, and the optimum recording power is determined by the adjustment process based on the reproduction signal in which the influence of the fluctuation is reduced. be able to.

  Hereinafter, a disk recording / reproducing apparatus according to the present invention will be described in detail with reference to the drawings showing an optical disk apparatus as an embodiment thereof. FIG. 1 is a block diagram showing a configuration example of a main part of an optical disc apparatus as a disc recording / reproducing apparatus according to the present invention. In FIG. 1, reference numeral 1 shows an optical disc apparatus as a disc recording / reproducing apparatus of the present invention.

  In the present embodiment, an optical disk apparatus 1 that performs data recording / reproduction processing on the optical disk 1a only with a laser beam (light beam) from the pickup 11 will be described as an example. However, the present invention is not limited as long as data is recorded / reproduced on / from a disk-shaped recording medium using a laser beam. For example, the present invention can also be applied to a magneto-optical disk recording / reproducing apparatus for recording / reproducing data on / from a magneto-optical disk using a laser beam from the pickup 11 and a magnetic field from a magnetic head. Therefore, as a recording medium, an optical disk such as CD-R, CD-RW, DVD-R, DVD-RW, DVD-RAM, DVD + RW, or magneto-optical disk such as MO can be used.

  The optical disc apparatus 1 of the present embodiment irradiates the surface of the optical disc 1a rotated by the rotation driving unit 16 and the rotation driving unit 16 that rotates the optical disc 1a mounted on a mounting tray (not shown) with laser light. A pickup 11 that performs data recording / reproduction processing, an RF signal generation unit 12 that generates an RF signal from an electrical signal that the pickup 11 reproduces and outputs data recorded on the optical disc 1a, and an RF signal generated by the RF signal generation unit 12 OPC processing unit 13 that performs OPC processing based on the above, RFRP signal generation unit 14 that generates an RFRP (Radio Frequency Ripple) signal from an RF signal, and amplitude that detects the amplitude of the RFRP signal generated by RFRP signal generation unit 14 The detection part 15 grade | etc., Is provided.

  Further, the optical disc apparatus 1 includes a control unit 10 constituted by a CPU (Central Processing Unit) or MPU (Micro Processor Unit) in which a ROM and a RAM are incorporated. The control unit 10 controls the operation of each hardware unit as described above, and appropriately reads and executes a control program stored in advance in a ROM built in the controller. In the ROM, various control programs necessary for operating the optical disc apparatus 1 as a disc recording / reproducing apparatus according to the present invention are stored in advance. The RAM is configured by SRAM, flash memory, or the like, and temporarily stores data generated when the control unit 10 executes the control program.

  The rotation drive unit 16 includes a motor that rotates the optical disc 1a, a motor drive circuit that drives the motor in accordance with control by the control unit 10, and the like. Such a rotation drive unit 16 rotates the optical disc 1a at a constant angular velocity (CAV) or a constant linear velocity (CLV) according to an instruction from the control unit 10.

  The pickup (recording means, reproducing means) 11 is disposed opposite to the optical disc 1a, and includes a laser diode that irradiates the surface of the optical disc 1a with laser light, a laser diode drive circuit that drives the laser diode, and the like. The pickup 11 irradiates a recording power laser beam when recording data on the optical disc 1a, and a reproducing power laser beam when reproducing data on the optical disc 1a. When the control unit 10 appropriately controls the rotation driving unit 16 and the pickup 11, the optical disc apparatus 1 records data by the pickup 11 at an appropriate address on the optical disc 1 a rotated by the rotation driving unit 16. Processing or reproduction processing can be performed.

  When the optical disc apparatus 1 reproduces data from the optical disc 1 a, the pickup 11 converts the reflected light from the optical disc 1 a of the laser beam irradiated by itself into an electrical signal and outputs it to the RF signal generator 12. Further, when the optical disc apparatus 1 records data on the optical disc 1a, the control unit 10 responds to the data to be recorded on the optical disc 1a based on the recording pulse width, recording power, and the like set in advance as optimum recording conditions. The generated recording pulse is generated and output to the pickup 11. The pickup 11 irradiates a laser beam in accordance with the recording pulse output from the control unit 10 and performs data recording processing at an appropriate address on the optical disc 1a.

  The RF signal generation unit 12 performs an amplification process on the electrical signal output from the pickup 11 and binarizes the amplified electrical signal based on a predetermined threshold voltage. The RF signal generation unit 12 performs a clock detection process using a PLL (Phase Locked Loop) circuit on the binarized signal obtained by the binarization process, and outputs the binarized signal based on the detected clock signal. By performing the decoding process, an RF signal that is a reproduction signal is generated. The RF signal obtained in this way is output to the OPC processor 13 or the RFRP signal generator 14. Further, the RF signal generation unit 12 performs a process of detecting data errors caused by noise, scratches or dirt on the optical disk 1a during the data reproduction process by the pickup 11, and the error correction is possible. The data correction process is also performed.

  The OPC processing unit 13 performs various processes in the OPC process for the pickup 11 to irradiate laser light having an optimum recording power. Specifically, the pickup 11 performs a recording process on a preset PCA (Power Calibration Area) area on the optical disc 1a while changing the recording conditions stepwise, and then is recorded in the PCA area. Based on the RF signal generated by the RF signal generation unit 12 when the data reproduction process is performed, the OPC processing unit (adjustment unit) 13 performs OPC processing (adjustment processing) for determining the optimum recording power.

  More specifically, the OPC processing unit 13 performs the maximum value A1 within a predetermined period for each recording condition with respect to the RF signal obtained by reproducing the data recorded in the PCA area on the optical disc 1a. Then, the β value is calculated by substituting the minimum value A2 into the following formula 1. In addition, a preset optimum β value is stored in a memory (not shown). Therefore, the OPC processing unit 13 can identify the optimum recording power by comparing each β value calculated for each recording condition with the optimum β value stored in the memory.

  β = (A1 + A2) / (A1-A2) (Formula 1)

  The recording power specified in this manner is the optimum recording power for the optical disc 1a, and this recording power is stored in a predetermined memory and used in the subsequent recording processing for the optical disc 1a. In the case where the optical disk apparatus 1 is configured to perform the running OPC process for sequentially adjusting the recording power as described above while performing the data writing process on the optical disk 1a, the recording power specified as described above. Is used in a recording process for a corresponding area on the optical disc 1a, that is, an area in which data is written before the next OPC process is performed.

  Further, when the pickup 11 performs the reproduction process of the PCA area on the optical disc 1a, the OPC processing unit 13 performs the binarization signal obtained by the binarization processing by the RF signal generation unit 12 and the clock by the PLL circuit. The jitter value of the RF signal may be calculated based on the phase difference from the clock signal detected by the detection process, and the optimum recording power may be determined based on the calculated jitter value. Specifically, the OPC processing unit 13 calculates a jitter value corresponding to each recording power set in stages for the OPC processing, and the calculated jitter value is, for example, a minimum value. Is determined as the optimum recording power. Note that a separate jitter measurement unit may be provided in the optical disc apparatus 1, and the jitter value may be measured by the jitter measurement unit.

  Based on the optimum recording power determined based on the β value or jitter value in the RF signal as described above, the control unit 10 generates a recording pulse corresponding to the data to be recorded on the optical disc 1a, and the pickup 11 The reliability of the data written on the optical disc 1a can be ensured by irradiating the laser beam in accordance with the recording pulse generated by the control unit 10 and performing the data recording process on the optical disc 1a.

  The optical disc apparatus 1 according to the present embodiment further includes an RFRP signal generation unit 14 and a swing width detection unit 15. The RFRP signal generation unit 14 includes a peak / bottom detection processing unit 14a, a difference calculation unit 14b, and the like. The peak / bottom detection processing unit 14a performs peak detection processing and bottom detection processing within a predetermined time of the RF signal generated by the RF signal generation unit 12 when the pickup 11 performs reproduction processing of the PCA area on the optical disc 1a. The difference calculating unit 14b calculates a difference between the peak detection signal and the bottom detection signal obtained by the peak / bottom detection processing unit 14a performing the peak detection processing and the bottom detection processing, and generates an RFRP signal. The RFRP signal generation unit 14 outputs the obtained RFRP signal to the fluctuation width detection unit 15.

  The swing width detection unit 15 includes an amplitude calculation unit 15a, a difference calculation unit 15b, a ratio calculation unit 15c, and the like. The amplitude calculator 15a calculates the average value of the amplitude of the RFRP signal generated by the RFRP signal generator 14 within a predetermined time. The difference calculation unit 15b calculates a difference between the maximum amplitude and the minimum amplitude of the RFRP signal generated by the RFRP signal generation unit 14 within a predetermined time. The ratio calculation unit 15c calculates the ratio of the difference calculated by the difference calculation unit 15b with respect to the average value of the amplitude calculated by the amplitude calculation unit 15a.

  2A and 2B are waveform diagrams of a reproduction signal in the optical disc apparatus 1 according to the present embodiment. FIG. 2A shows an RF signal generated by the RF signal generator 12, and FIG. 2B shows an RFRP signal generator 14. The RFRP signals generated by are respectively shown. In the waveform diagram of FIG. 2, the horizontal axis represents time, and the vertical axis represents voltage. The RFRP signal generator 14 generates an RFRP signal as shown in FIG. 2B from the RF signal as shown in FIG. The amplitude calculation unit 15a of the fluctuation detection unit 15 calculates the average amplitude S of the RFRP signal at the predetermined time T shown in FIG. 2B and the difference W between the maximum amplitude and the minimum amplitude of the RFRP signal at the predetermined time T. . The average amplitude S is an average value of each potential sampled at an appropriate interval within the predetermined time T of the RFRP signal, and the difference W indicates the amplitude of the RFRP signal within the predetermined time T.

  The ratio calculator 15c of the swing width detector 15 calculates a ratio P (W / S) of the swing width W with respect to the average amplitude S calculated by the amplitude calculator 15a and the difference calculator 15b. Here, the fluctuation width W of the RFRP signal is the vibration received by the optical disk 1a due to an external shock received by the optical disk apparatus 1, the abnormal vibration received by the optical disk 1a from the rotation drive unit 16 during the data recording / reproducing process, or the like. This is based on vibration that occurs temporarily. Therefore, in the optical disc apparatus 1 according to the present embodiment, when the ratio P of the fluctuation width W to the average amplitude S is larger than a predetermined threshold value, the optical disc 1a temporarily vibrates during the OPC process. In the OPC process, the OPC processing unit 13 acquires a β value or a jitter value based on the RF signal a plurality of times, and determines an optimum recording power based on the average value.

  Specifically, when the pickup 11 performs a reproduction process of data recorded in the PCA area on the optical disc 1a, the OPC processing unit 13 performs, for example, 100 msec for the RF signal generated by the RF signal generating unit 12. It is assumed that a β value based on the maximum value A1 and the minimum value A2 is calculated and an OPC process based on the β value is performed. During this time, when the ratio P of the fluctuation width W with respect to the average amplitude S of the RFRP signal becomes, for example, 0.1 or more, the OPC processing unit 13 continuously sets the β value for 100 msec to 2 for the RF signal. The average value of the three β values is calculated, and the OPC process is performed based on the calculated average value to identify the optimum recording power. Note that the predetermined threshold and the predetermined sampling time are stored in advance in the ROM of the control unit 10, for example, and the OPC processing unit 13 performs the above-described processing in accordance with an instruction from the control unit 10.

  In the following, for simplicity of explanation, the optical disc apparatus 1 configured to perform OPC processing using only the β value will be described. However, as described above, the ratio P of the fluctuation width W to the average amplitude S of the RFRP signal is determined in advance. When the predetermined threshold value is exceeded, the optical disk apparatus 1 is configured to calculate the jitter value of the RF signal within a predetermined time a plurality of times and perform OPC processing based on the average value of the calculated jitter values. It can also be configured. When the optical disc apparatus 1 has a configuration for determining the optimum recording power based on the number of errors (errors) in the RF signal, as described above, the fluctuation width with respect to the average amplitude S of the RFRP signal. When the ratio P of W becomes larger than a predetermined threshold value set in advance, the number of errors in the RF signal within a predetermined time is detected a plurality of times, and an OPC process based on the average value of the detected plurality of errors is performed. The optimum recording power may be determined.

  As described above, when abnormal vibration that occurs temporarily is added to the RF signal, the β value, jitter value, or number of errors used for the OPC process is sampled a plurality of times, and the OPC process is performed based on the average value of these values. By performing the above, it is possible to reduce the influence of abnormal fluctuations in the RF signal and perform stable OPC processing. Therefore, the reliability of the data written on the optical disc 1a can be more stably ensured by the optimum recording power determined by such OPC processing.

  Hereinafter, a process for detecting a fluctuation in the RF signal when performing the OPC process in the optical disc apparatus 1 having the above-described configuration will be described. FIG. 3 is a flowchart showing a procedure of RF signal fluctuation detection processing in the optical disc apparatus 1 according to the present invention. The following processing is executed by the control unit 10 according to a control program stored in advance in a ROM built in the control unit 10.

  In the optical disc apparatus 1, the control unit 10 performs an OPC process when recording data on the optical disc 1a by the pickup 11, and reproduces data recorded in the PCA area on the optical disc 1a by the pickup 11. The RF signal generated by the RF signal generator 12 is acquired (S1).

  Next, the control unit 10 generates an RFRP signal by the RFRP signal generation unit 14 based on the RF signal generated by the RF signal generation unit 12 (S2). The control unit 10 determines whether or not the predetermined time T has elapsed with its own timer (not shown) (S3), and if it is determined that the predetermined time T has not elapsed (S3: NO), the process proceeds to step S1. The RF signal generation processing by the RF signal generation unit 12 and the RFRP signal generation processing by the RFRP signal generation unit 14 are continued.

  When it is determined that the predetermined time T has elapsed (S3: YES), the control unit 10 calculates the average amplitude S of the RFRP signal generated by the RFRP signal generation unit 14 at the predetermined time T by the fluctuation detection unit 15 ( S4) The fluctuation width W of the RFRP signal at the predetermined time T is calculated (S5). Further, the control unit 10 calculates the ratio P of the swing width W with respect to the average amplitude S by the swing width detection unit 15 (S6), and the calculated ratio P of the swing width W is larger than a predetermined threshold value set in advance. It is determined whether it is small (S7).

  When the control unit 10 determines that the ratio P is smaller than the threshold value (S7: YES), the control unit 10 ends the above-described processing, and the OPC processing unit 13 executes normal OPC processing based on the RF signal acquired in step S1. (S8) The optimum recording power is determined. When the control unit 10 determines that the ratio P is larger than the threshold (S7: NO), the OPC processing unit 13 executes the OPC processing in which the number of samplings is increased based on the RF signal acquired in step S1 ( S9) The optimum recording power is determined. Specifically, the control unit 10 calculates the β value within the predetermined time T twice in succession by the OPC processing unit 13 with respect to the RF signal acquired in step S1, and adds three β values. OPC processing is performed based on the average value of.

  The control unit 10 stores the optimum recording power determined as described above in a predetermined memory, and should record on the optical disc 1a based on the optimum recording power in the subsequent recording processing. A recording pulse corresponding to the data is generated and output to the pickup 11. Accordingly, since the pickup 11 irradiates the laser beam with the optimum recording power according to the recording pulse output from the control unit 10, it is possible to stably ensure the reliability of the data recorded on the optical disc 1a. .

  In the embodiment described above, the β value used for the OPC process is calculated a plurality of times when the optical disk 1a is subjected to abnormal vibration and the ratio P of the fluctuation width W to the average amplitude S of the RFRP signal becomes larger than a predetermined threshold value. The optical disk apparatus 1 having the configuration for specifying the optimum recording power based on the average value has been described. However, it is also possible to extend the sampling time for calculating the β value used for the OPC process and specify the optimum recording power based on the β value at the extended sampling time. Specifically, when the OPC processing unit 13 calculates a β value based on the maximum value A1 and the minimum value A2 for 100 msec, for example, for the RF signal and performs the OPC processing based on the β value, sampling is performed. For example, the time may be 300 msec, the β value based on the maximum value A1 and the minimum value A2 during 300 msec may be calculated, and the optimum recording power may be specified based on the calculated average value.

  In the optical disc apparatus 1 configured to perform the OPC process for determining the optimum recording power based on the jitter value or the number of errors in the RF signal, similarly, the sampling time for calculating the jitter value or the number of errors is extended, An optimum recording power can be determined based on the jitter value or the number of errors in the extended sampling time.

  Further, the predetermined threshold value for determining whether or not abnormal vibration is added to the RF signal is not limited to the configuration stored in advance in the ROM of the control unit 10. For example, the optical disc 1 a is mounted on the optical disc apparatus 1. Immediately after that, the ratio P of the fluctuation width W to the average amplitude S of the RFRP signal may be detected, and the threshold value may be determined based on this detection result.

It is a block diagram which shows the principal part structural example of the optical disk apparatus as a disk recording / reproducing apparatus based on this invention. FIG. 6 is a waveform diagram of a reproduction signal in the optical disc apparatus according to the present embodiment. 5 is a flowchart showing a procedure of RF signal fluctuation detection processing in the optical disc apparatus according to the present invention.

Explanation of symbols

1. Optical disc device (disc recording / playback device)
1a Optical disc (recording medium)
10 control section 11 pickup (recording means, reproducing means)
13 OPC processor (adjustment means)
15 Swing width detector 15a Amplitude calculator (amplitude calculator)
15b Difference calculation unit (difference calculation means)
15c ratio calculation unit (ratio calculation means)

Claims (3)

Recording means for recording data by irradiating a light beam onto a disk-shaped recording medium, reproduction means for reproducing data recorded by the recording means and outputting a reproduction signal, and reproduction signal output by the reproduction means In a disk recording / reproducing apparatus comprising adjustment means for performing adjustment processing for optimally adjusting the recording power of the light beam when recording data based on the state,
Difference calculating means for calculating a difference between a maximum value and a minimum value within a predetermined time of the reproduction signal output by the reproduction means;
Amplitude calculating means for calculating an average value of the amplitude of the reproduction signal within the predetermined time;
A ratio calculating means for calculating a ratio of the difference calculated by the difference calculating means with respect to the average value of the amplitude calculated by the amplitude calculating means;
The disc recording / reproducing apparatus according to claim 1, wherein the adjusting means is configured to perform an adjustment process according to the ratio calculated by the ratio calculating means. The adjusting means includes
Performing adjustment processing for adjusting the recording power of the light beam based on a value obtained by sampling the reproduction signal at each predetermined time;
When the ratio calculated by the ratio calculation unit is larger than a preset threshold value, the adjustment process is performed based on an average value of a plurality of values obtained by sampling the reproduction signal a plurality of times at the predetermined time. 2. The disc recording / reproducing apparatus according to claim 1, wherein the disc recording / reproducing apparatus is configured as described above. The adjusting means includes
Performing adjustment processing for adjusting the recording power of the light beam based on a value obtained by sampling the reproduction signal at each predetermined time;
When the ratio calculated by the ratio calculation unit is greater than a preset threshold, the adjustment process is performed based on a value obtained by sampling the reproduction signal every time longer than the predetermined time. The disc recording / reproducing apparatus according to claim 1, wherein

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