JP4458014B2 - Optical disc recording method and optical disc apparatus - Google Patents

Description

  The present invention relates to an optical disc recording method and an optical disc apparatus for recording information on an optical disc by an optical pickup.

  Optical disk devices are actively being developed for various applications and high performance. In particular, recently, with the widespread use of rewritable optical discs, the demand for rewritable optical discs has increased, and the requirement for overwriting recording quality is one of them.

  Here, the configuration of a conventional optical disc apparatus will be described with reference to the drawings.

  FIG. 7 is a block diagram of an optical pickup control unit in a conventional optical disc apparatus. In FIG. 7, 501 is a laser diode, 502 is an optical pickup, 503 is a light receiving circuit, 504 is a photodiode, 505 is a motor driver circuit, 506 is a laser driver circuit, 507 is a servo signal generation circuit, 508 is an analog signal generation circuit, 509 is a recording pattern generation circuit, 510 is a laser power control circuit, 511 is an A / D converter, 512 is a controller, 513 is a ROM, 514 is a RAM, 515 is a storage unit, 21 is an optical disk, and 22 is a spindle motor.

  The operation of the optical pickup control unit in the conventional technology configured as described above will be described.

  The laser diode 501 emits a recording or reproduction laser to the optical disc 21. The laser diode 501 is driven by a laser driver circuit 506 that supplies current to the laser diode 501, and the laser driver circuit 506 controls a timing of an output current of the laser driver circuit 506 and a light emission pattern of laser power. And a laser power control circuit 510 that provides a voltage for controlling the output current of the laser driver circuit 506. The recording pattern generation circuit 509 and the laser power control circuit 510 are respectively connected to the controller 512, and transmit / receive signals for controlling the optical pickup 502.

  On the other hand, the laser light emitted from the laser diode 501 passes through the optical pickup 502 and is refracted, condensed and diffracted, and reaches the optical disc 21. The laser light reaching the optical disc 21 is reflected, passes through the optical pickup 502 again, and reaches the light receiving circuit 503. The light receiving circuit 503 receives the reflected light from the optical disc 21 and converts it into an electrical signal. The converted electrical signal is sent to an analog signal generation circuit 508, where an analog signal such as an RF signal is generated and sent to the A / D converter 511, the controller 512, and the servo signal generation circuit 507. Here, the analog signal sent to the A / D converter 511 is measured for the magnitude of the analog signal, and the information is sent to the controller 512. The controller 512 stores the OPC (Optimum Power) stored in the storage unit 515 of the ROM 513 in advance. The optimum recording power is determined using the parameter of the (Control) parameter. Further, the servo signal generation circuit 507 sends a control signal that rotates at an appropriate rotation number to the motor driver circuit 505 based on the signal received from the analog signal generation circuit 508. The motor driver circuit 505 receives the control signal, generates a voltage for rotating the spindle motor 22, and rotates the spindle motor 22.

  A part of the laser light emitted from the laser diode 501 is received by the photodiode 504, converted into an electric signal, sent to the laser power control circuit 510, and used for feedback of the laser power control circuit 510.

  Next, a method for determining the optimum recording power in a rewritable optical disc will be described taking the case where the optical disc is a CD-RW as an example.

  FIG. 8 is a flowchart showing a conventional optical disc recording method.

  When the optical disk 21 is inserted, the optical disk apparatus first rotates the spindle motor 22 and applies focus servo and tracking servo to determine the type of optical disk (S101). Next, in order to obtain the optimum recording power for recording on the optical disc 21, the disc information such as the manufacturer name and grade embedded in the optical disc 21 in advance is read (S102). Then, OPC parameters are selected based on the read information (S103), and the recording power is determined by OPC (S104).

  Determination of the recording power by OPC is performed by first performing test writing in a test writing area provided on the optical disc 21 and reproducing the test writing portion after a certain amount of test writing has been completed. The reflected light returned from the optical disk 21 when the test writing portion is reproduced is received by the light receiving circuit 503, converted into an electric signal, and sent to the controller 512 via the analog signal generation circuit 508 and the A / D converter 511. The controller 512 records the data requested by the user using the determined recording power (S105).

As a prior example, there is (Patent Document 1) and the like.
JP-A-9-198661

  When data is recorded on a rewritable optical disc, an OPC operation is performed in consideration of the manufacturer and grade of the rewritable optical disc to be used. In the OPC operation, when the manufacturer and grade of the rewritable optical disk to be used are the same, the same OPC parameter is selected, and trial writing is performed using the OPC parameter. Then, the optimum recording power is determined by reproducing the test writing portion. Here, in the trial writing performed, when the rewritable optical disk to be used is the same, the optimum recording power is the same regardless of the number of data recordings.

  However, when overwriting is performed on a rewritable optical disk that has already been used, if overwriting is performed with a recording power equal to or lower than the recording power used for the first recording of the rewritable optical disk, 1 The second recording cannot be completely rewritten, and the recording quality is deteriorated.

  Hereinafter, a case where two recording marks having the same length are recorded on a rewritable optical disk (hereinafter simply referred to as “optical disk”) will be described.

  FIG. 9 is a diagram showing a relationship between a recording waveform and a recording mark on the optical disk surface in a conventional optical disk recording method. FIG. 9A shows the first data recording frequency of the optical disc used, and FIG. 9B shows the second data recording frequency of the optical disc used. FIG. 9 (c) shows the third data recording frequency of the optical disk to be used. 9 (a), 9 (b), and 9 (c), a recording waveform when recording on the optical disk from above, a recording state on the optical disk surface based on the recording waveform, and on the optical disk surface An RF signal based on a recording state and a binarized signal based on the RF signal are shown. FIG. 10 is a diagram showing the number of optical disk recordings and the error rate in the conventional optical disk recording method, where the horizontal axis represents the number of recordings and the vertical axis represents the error rate. FIG. 11 is a diagram showing the number of optical disc recordings and jitters in a conventional optical disc recording method, where the horizontal axis shows the number of recordings and the vertical axis shows the jitter. In FIG. 9, 201 is a recording pulse, 202 is a recording track, 211, 212, 221, 222, 231, 232 are recording marks.

  FIG. 9A shows a case where the number of times of data recording on the optical disk 21 is the first time, that is, a case where recording is first performed on an unused optical disk 21. In this case, since there are no recording marks already recorded on the recording track 202, the recording marks 211 and 212 having the same length can be recorded without being affected by the recording marks already recorded. The RF signal when reproducing the recording marks 211 and 212 recorded in this way and the binarized signal based on the RF signal are as shown in FIG. 9 (a). can do.

  FIG. 9B shows a case where two recording marks 221 and 222 having the same recording length as those in FIG. 9A that have already been recorded are overwritten. The recording mark 221 has already been recorded. The case where overwrite recording is performed from the middle of the recording mark 211 is shown, and the case where the recording mark 222 is overwritten at the same position as the recording mark 212 already recorded is shown. Since the recording mark 222 is overwritten and recorded at the same position as the recording mark 212 already recorded, the recording of the recording mark 222 is equivalent to the case where recording is first performed on the unused optical disk 21.

  Further, since the recording mark 221 is overwritten and recorded from the middle of the recording mark 211 that has already been recorded, it is necessary to newly record the recording mark 221 while erasing the recording mark 211 that has already been recorded. Therefore, the RF signal when reproducing the recording marks 221 and 222 recorded in this way and the binarized signal based on the RF signal are as shown in FIG. The recording mark 221 to be overwritten from the middle of 211 and the recording mark 222 to be overwritten at the same position as the already recorded recording mark 212 cannot be reproduced with the same length.

  FIG. 9 (c) shows a case where two recording marks 231 and 232 having the same recording length as those in FIG. 9 (b) which have already been recorded are overwritten. Both recording marks 231 and 232 have already been recorded. A case where overwriting is performed from the middle of the recorded recording marks 221 and 222 is shown. Since the recording marks 231 and 232 are overwritten and recorded in the middle of the already recorded recording marks 221 and 222, respectively, the recording marks 231 and 232 are newly erased while erasing the already recorded recording marks 221 and 222. Need to record. In this case, the RF signal when reproducing the recording marks 231 and 232 recorded in this way and the binarized signal based on the RF signal are as shown in FIG. Can be played back with the same length.

  As shown in FIG. 9B, when the recording marks 221 and 222 having the same length are recorded but cannot be reproduced as the recording marks 221 and 222 having the same length at the time of reproduction, the recording marks 221 and 222 shown in FIG. As shown, the recording quality deteriorates such that the number of times of recording data on the optical disk 21 to be used has a peak at the second time. As a cause of this, when the number of times of data recording on the optical disk 21 to be used is the second time, when a recording mark is overwritten on a recording mark already recorded and when a recording mark is recorded on an unrecorded portion This is because there is a large variation in the data length of the binarized signal based on the RF signal.

  This is the so-called jitter deterioration, which causes the error rate, which is an indicator of recording quality, to deteriorate. When the number of times of data recording on the optical disk 21 to be used is the third or later, the unrecorded portion in the recording track of the optical disk to be used decreases, so that the variation in the recording mark length is reduced and the recording quality is stabilized.

  The present invention solves such a conventional problem, and provides an optical disc recording method and an optical disc apparatus capable of improving the overwrite recording quality of a rewritable optical disc and reducing the probability of recording failure. The purpose is to provide.

  The present invention has been made to solve the above-described problem, and is an optical disc recording method characterized in that the recording power for recording data on the optical disc is switched according to the number of times of data recording on the rewritable optical disc to be used. is there.

  An optical pickup for recording data on the optical disc, a recording power control unit for controlling the recording power of the optical pickup, and a control unit for determining the recording power and controlling the recording power control unit are provided. The optical disc apparatus is characterized in that the recording power for recording data is switched according to the number of times of data recording of the rewritable optical disc to be used.

According to the present invention, the recording power for the first recording on the rewritable optical disk is made smaller than the recording power for the second and subsequent recordings on the rewritable optical disk. The optimum recording power can be set accordingly.

  Therefore, it is possible to improve the overwrite recording quality of the rewritable optical disc, and to realize an optical disc recording method and an optical disc apparatus capable of reducing the probability of recording failure.

According to a first aspect of the present invention, there is provided a light source that emits laser light, an optical pickup that records data on a rewritable optical disk using the laser light, current supply means that supplies current to the light source, and the current supply means. A laser power control means for operating and controlling the recording power of the optical pickup; and a control means for determining the recording power of the optical pickup; and the control means for the first recording on the rewritable optical disc A recording power for recording on the rewritable optical disk for the second time or later, and a test writing area which is a non-user data recording area of the rewritable optical disk by moving the optical pickup, Check the presence or absence of data or signals in the data management area and lead-in area. Is determined to be the first recording on the rewritable optical disk when none of the signals are in the respective areas, and the second time is recorded on the rewritable optical disk when at least one of the data or the signal is present. At the same time, it is determined that the data is recorded in the non-user data recording area, and the detection operation is performed in the order of the test writing area, the data area, and the lead-in area. If it exists, the rewritable optical disc is immediately judged as the second or later recording. Thereby, the optimum recording power can be set according to the recording state of the rewritable optical disk. Therefore, the overwrite recording quality of the rewritable optical disk can be improved, and an optical disk device capable of reducing the probability of recording failure can be realized. In addition, it is possible to improve the recording quality of the second data recording number that the recording quality is the lowest among the rewritable allowable number of times of the rewritable optical disc. Furthermore, it is possible to grasp whether the recording status of the rewritable optical disk to be used is unused or already used without recording new information indicating the number of times of data recording in the rewritable optical disk.

According to a second aspect of the invention, there is provided an optical disk recording method for recording on a rewritable optical disc while changing the recording power of the optical pickup, the recording power at the time of first recording on the rewritable optical disc in the rewritable optical disk On the other hand, it is a non-user data recording area of the rewritable optical disc when it is made smaller than the recording power at the time of recording for the second time or later and when it is determined whether or not the rewritable optical disc is recorded first. The presence or absence of data or signals in the test writing area, data management area, and lead-in area is confirmed, and when there is no data or signals, it is determined as the first recording on the rewritable optical disc, and the data or If there is at least one of the signals, the rewritable optical disc In the detection of data or signals in the non-user data recording area, a detection operation is performed in the order of the test writing area, the data area, and the lead-in area, and the test writing is performed. If there is data in the area, the rewritable optical disc is immediately judged as the second or subsequent recording. Thereby, the optimum recording power can be set according to the recording state of the rewritable optical disk. Therefore, the overwrite recording quality of the rewritable optical disk can be improved, and an optical disk recording method capable of reducing the probability of recording failure can be realized. In addition, it is possible to improve the recording quality of the second data recording number that the recording quality is the lowest among the rewritable allowable number of times of the rewritable optical disc.

(Embodiment 1)
Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

  FIG. 1 is a block diagram of an optical pickup control unit of an optical disc apparatus according to an embodiment of the present invention. In FIG. 1, 1 is a laser diode, 2 is an optical pickup, 3 is a light receiving means, 4 is a photodiode, 5 is a motor driver means, 6 is a laser driver means, 7 is a servo signal generating means, 8 is an analog signal generating means, 9 is a recording pattern generation means, 10 is a laser power control means, 11 is an A / D converter, 12 is a controller, 13 is ROM, 14 is RAM, 15 and 16 are storage units, 21 is an optical disk, and 22 is a spindle motor. .

  The operation of the optical pickup control unit configured as described above will be described.

  The laser diode 1 emits a recording or reproducing laser to the optical disk 21. The laser diode 1 is driven by laser driver means 6 for supplying a current to the laser diode 1, and the laser driver means 6 is a recording pattern generating means 9 for controlling the timing of the output current of the laser driver means 6 and the light emission pattern of the laser power. And the laser power control means 10 for applying a voltage for controlling the output current of the laser driver means 6. The recording pattern generation means 9 and the laser power control means 10 are respectively connected to the controller 12 and transmit / receive signals for controlling the optical pickup 2.

  On the other hand, the laser light emitted from the laser diode 1 passes through the optical pickup 2, is refracted, condensed and diffracted, and reaches the optical disk 21. The laser light that has reached the optical disk 21 is reflected, passes through the optical pickup 2 again, and reaches the light receiving means 3. The light receiving means 3 receives the reflected light from the optical disk 21 and converts it into an electrical signal. The converted electric signal is sent to the analog signal generation means 8, which generates an analog signal such as an RF signal and sends it to the A / D converter 11, the controller 12 and the servo signal generation means 7. The analog signal sent to the A / D converter 11 is measured for the magnitude of the analog signal, and the information is sent to the controller 12. The controller 12 stores the OPC (Optimum Power) stored in the storage unit 15 of the ROM 13 in advance. The optimum recording power is determined using the Control parameter.

  The servo signal generation means 7 sends a control signal that rotates at a desired rotational speed to the motor driver means 5 based on the signal received from the analog signal generation means 8. The motor driver means 5 receives the control signal, generates a voltage for rotating the spindle motor 22, and rotates the spindle motor 22.

  Part of the laser light emitted from the laser diode 1 is received by the photodiode 4, converted into an electrical signal, sent to the laser power control means 10, and used for feedback of the laser power control means 10.

  Here, the controller 12 constitutes a control unit of the present invention. The controller 12 includes at least an arithmetic processing unit, and includes a motor driver unit 5, a laser driver unit 6, a servo signal generation unit 7, an analog signal generation unit 8, and a recording pattern generation. Signals sent from means 9, laser power control means 10, A / D converter 11, ROM 13, and RAM 14 are input, calculation processing of these signals is performed, and the result (signal) of this calculation processing is sent to each part. Then, each part is driven and processed, and each part is controlled.

  Next, the case of CD-RW will be described as an example of the data area configuration of a rewritable optical disc (hereinafter simply referred to as “optical disc”).

  FIG. 2 is a diagram showing a data recording area configuration of the CD-RW disc. In FIG. 2, 301 is a center hole, 302 is a non-user data recording area, 302a is a test writing area (PCA area), 302b is a data management area (PMA area), 302c is a lead-in area (LeadIn area), and 303 is a user. This is a data recording area.

  The optical disk 21 is arranged in the order of a non-user data recording area 302 and a user data recording area 303 from the center hole 21 provided in the center of the disk toward the outer periphery in the radial direction. The non-user data recording area 302 includes a test writing area 302a, a data management area 302b, and a lead-in area 302c. In the trial writing area 302a, trial writing used for an OPC operation for obtaining the optimum recording power for recording on the surface of the optical disk 21 is performed, and in the data management area 302b, provisional disk management information is written in a state that allows additional writing. In the lead-in area 302c, final disc information such as TOC (Table Of Contents) is written. The user use area 303 is an area where writing is performed according to a user instruction.

  Since the trial writing area 302a is an area where an OPC operation for obtaining the optimum recording power for recording is performed, in the case of an unused optical disk 21, nothing is recorded. Similarly, since the data management area 302b is an area where temporary disk management information is written, in the case of an unused optical disk 21, nothing is recorded. Similarly, since the lead-in area 302c is an area where final disc information is written, in the case of an unused optical disc 21, nothing is recorded.

  If nothing is recorded in all of the test writing area 302a, the data management area 302b, and the lead-in area 302c, the optical disk 21 is in an unused state. On the other hand, if something is recorded in any of the test writing area 302a, the data management area 302b, and the lead-in area 302c, the optical disk 21 is already in use.

  As described above, it is determined whether or not the optical disc 21 is unused or has already been used by checking whether or not any information is recorded in the test writing area 302a, the data management area 302b, and the lead-in area 302c. can do. When the optical disc 21 is not used, the data recording count of the optical disc 21 to be used is the first recording, and when it is already used, the data recording count of the optical disc 21 to be used is the second recording or later. .

  Next, a case of CD-RW will be described as an example of a rewritable optical disc (hereinafter simply referred to as “optical disc”) recording method in the present invention.

  FIG. 3 is a flowchart showing an optical disk recording method according to an embodiment of the present invention.

  When the optical disk 21 is loaded in the optical disk apparatus, the controller 12 issues a command to rotate the spindle motor 22 to the servo signal generation means 7, and the servo signal generation means 7 controls the motor driver means 5 to rotate at a desired rotational speed. Send a signal. The motor driver means 5 receives the control signal, generates a voltage for rotating the spindle motor 22, and rotates the spindle motor 22.

  Next, the controller 12 sends a command to the laser power control means 10 to emit light with reproduction power. The laser power control means 10 sets the reproduction power and gives a voltage to the laser driver means 6. The laser driver means 6 generates a current corresponding to the applied voltage and causes the laser diode 1 to emit light. A part of the light emitted from the laser diode 1 is received by the photodiode 4, and the photodiode 4 generates a voltage corresponding to the amount of light. The voltage generated in the photodiode 4 is input to the laser power control means 10, and the laser power control means 10 detects the power set by the laser power control means 10 by measuring the voltage, and if necessary, The voltage applied to the laser driver means 6 is controlled.

  Thereafter, the controller 12 instructs the servo signal generation means 7 to focus. The servo signal generation means 7 sends a signal for moving the lens in the optical pickup 2 up and down to the motor driver means 5. The motor driver means 5 generates a voltage based on the transmitted signal, and moves the lens in the optical pickup 2 up and down. The light receiving means 3 receives the reflected light from the optical disk 21 and generates a voltage. The analog signal generation unit 8 generates a focus signal from the voltage generated by the light receiving unit 3 and inputs the focus signal to the servo signal generation unit 7. Since the focus signal changes depending on the top and bottom of the lens of the optical pickup 2, the servo signal generating means 7 stops the lens in the optical pickup 2 at the optimal position when the focus signal reaches the optimal lens position. A signal is sent to the driver means 5 to bring the focus on. Then, the servo signal generation means 7 controls the signal given to the motor driver means 5 so that the lens position is always optimal based on the focus signal produced by the analog signal generation means 8.

  A servo signal such as a tracking error signal generated by the analog signal generating means 8 is input to the A / D converter 11 where the voltage of the signal is measured. Then, from the measured voltage, the controller 12 determines the type of the optical disc 21, such as DVD, CD, CD-RW, etc. (S1).

  Next, in order to obtain the optimum recording power for recording on the optical disk 21, the controller 12 reads disk information such as manufacturer name and grade embedded in the optical disk 21 in advance, and the storage section of the ROM 13 based on the information. The OPC parameters stored in 15 are taken out, and the OPC parameters are set for the servo signal generation means 7, the recording pattern generation means 9, and the laser power control means 10 (S2). For example, when the optical disk 21 loaded in the optical disk apparatus is a CD-RW, the controller 12 reads various parameters for the CD-RW in consideration of the manufacturer name and grade from the ROM 13, and based on the information, The OPC parameters stored in the storage unit 15 are taken out, and the OPC parameters are set for the servo signal generation means 7, the recording pattern generation means 9, and the laser power control means 10.

  Next, the presence / absence of information in the non-user data recording area 302 is confirmed. To confirm the presence or absence of information in the non-user data recording area 302, the controller 12 moves the optical pickup 2 to each of the test writing area 302a, the data management area 302b, and the lead-in area 302c, and reads the information of each area. Done in

  In the test writing area 302a, it is determined whether or not there is OPC start address information (S3). Here, if there is OPC start address information, confirmation of the presence or absence of the RF signal in the data management area 302b and the lead-in area 302c is omitted, and the process proceeds to step 7 (S7). If there is no OPC start address information, the presence / absence of RF signals in the data management area 302b and lead-in area 302c is continuously checked.

  In the data management area 302b, the A / D converter 11 measures the amplitude of the RF signal generated by the analog signal generation means 8 to determine the presence or absence of the RF signal (S4). If there is an RF signal, the disk information confirmation in the lead-in area 302c is omitted, and the process proceeds to step 7 (S7). If there is no RF signal, the presence or absence of the RF signal in the lead-in area 302c is continuously checked.

  In the lead-in area 302c, the A / D converter 11 measures the amplitude of the RF signal generated by the analog signal generating means 8 to determine the presence or absence of the RF signal (S5). If there is an RF signal, the process proceeds to step 7 (S7). When there is no RF signal, the controller 12 sets an initial write flag (S6).

  Next, an OPC operation is performed using the set OPC parameters to determine the recording power (S7).

  The recording power determination by the OPC operation is composed of three processes: a recording process, a reproduction process, and a determination process.

  In the recording process, the recording power is set in the laser power control means 10 in accordance with the OPC parameter acquired by the controller 12. The laser power control means 10 applies a voltage to the laser driver means 6 according to the set recording power, and causes the laser diode 1 to emit light. The recording operation is performed in the unrecorded area of the test writing area 302a. The recording power is changed by the value determined by the OPC parameter every time one sector recording is performed, and this is repeated a predetermined number of times. For example, if the predetermined number of times is 10, the recording is performed with the recording power changed by 10 steps for each of 10 sectors.

  In the reproduction process, the controller 12 moves the optical pickup 2 to the sector on which trial writing has been performed, and reproduces the portion on which the trial writing has been performed. The A / D converter 11 measures the voltage, for example, the maximum value and the minimum value of the RF signal generated by the analog signal generation means 8 during reproduction. A predetermined number of RF signal voltage values recorded with different recording powers are stored in the RAM 14.

  In the determination process, the controller 12 determines the optimum recording power based on the RF signal voltage value stored in the RAM 14 during the reproduction process.

  Next, the controller 12 confirms the presence or absence of the initial write flag (S8).

  Here, when there is no initial write flag, that is, when there is information in the trial writing area 302a, there is an RF signal in the data management area 302b, or there is an RF signal in the lead-in area 302c. Determines that the optical disk 21 has been used at least once. In this case, the controller 12 performs a recording operation using the optimum recording power determined in step 7 (S7) as it is (S10).

  Further, when there is an initial write flag, that is, when the trial writing area 302a is blank, there is no RF signal in the data management area 302b, and there is no RF signal in the lead-in area 302c, judge. In this case, the controller 12 performs a recording operation by multiplying the optimum recording power determined in Step 7 (S7) by a constant magnification (S9) and using the calculated value as the true optimum recording power (S10).

  In this way, by determining whether the optical disk 21 to be used is unused or has already been used based on the information recorded in the non-user data recording area 302 of the optical disk 21 to be used, the optical disk 21 It is possible to grasp whether the recording status of the optical disc 21 to be used is unused or already used without recording new information indicating the number of times of data recording.

  The value of the constant magnification used in step 9 (S9) is stored in the storage unit 16 of the ROM 13, and the value is smaller than 1. By doing in this way, the recording power when the optical disk to be used is not used can be made smaller than the recording power when it is already used. Moreover, it is preferable that the value of the fixed magnification used is 0.85-0.95. By doing so, the recording power when the optical disc 21 to be used is not used can be set to 85 to 95% with respect to the recording power when the optical disc 21 to be used is already used. The recording quality of the second time of data recording on the optical disc 21 can be improved efficiently.

  In the present embodiment, the constant magnification value used in step 9 (S9) has been described as one, but the present invention is not limited to this. There may be a plurality of types of constant magnification values used in step 9 (S9) in consideration of the operating temperature in the optical disk apparatus. In the present embodiment, the OPC parameter is stored in the storage unit 15 of the ROM 13 and the constant magnification value is stored in the storage unit 16 of the ROM 13. However, the present invention is not limited to this.

  Next, a case where two recording marks having the same length are recorded on an unused rewritable optical disk (hereinafter simply referred to as “optical disk”) will be described.

  FIG. 4 is a diagram showing the relationship between the recording waveform of the optical disk recording method and the recording marks on the optical disk surface in one embodiment of the present invention. FIG. 4A shows the first data recording frequency of the optical disc used, and FIG. 4B shows the second data recording frequency of the optical disc used. FIG. 4 (c) shows the third recording of data on the optical disk to be used. 4 (a), 4 (b), and 4 (c), a recording waveform when recording on the optical disk from above, a recording state on the optical disk surface based on the recording waveform, and on the optical disk surface An RF signal based on a recording state and a binarized signal based on the RF signal are shown. In FIG. 4, 101 and 201 are recording pulses, 202 is a recording track, and 111, 112, 221, 222, 231 and 232 are recording marks.

  FIG. 4A shows a case where the number of times data is recorded on the optical disk 21 to be used is the first time, that is, the first recording is performed on the unused optical disk 21. When recording marks are recorded on an unused optical disk 21 for the first time, recording power for recording recording powers 111 and 112 is used, and recording power for recording recording marks 221, 222, 231, and 232 recorded later. The recording power for recording the recording powers 111 and 112 is set to be smaller than the recording power for recording the recording marks 221, 222, 231, and 232 recorded later. In this way, it is possible to set optimum recording conditions depending on the case where the optical disk 21 to be used is unused and when it is already used. Among them, it is possible to improve the recording quality of the second data recording frequency at which the recording quality is most deteriorated.

  Furthermore, the recording power for recording the recording marks 111 and 112 is preferably 85 to 95% of the recording power for recording the recording marks 221, 222, 231 and 232 recorded later. By doing in this way, the recording quality of the data recording frequency of the optical disk 21 to be used can be improved efficiently. In the present embodiment, when the recording power for recording the recording marks 221, 222, 231, 232 to be recorded later is about 40 mW, the recording power for recording the recording marks 111, 112 is about 35 mW.

  When the number of times of data recording on the optical disk 21 to be used is the first time, there is no recording mark recorded on the recording track 202, so that there is no influence of the recording mark already recorded. Therefore, the recording power for recording the recording marks 111 and 112 may be 85 to 95% of the value calculated when the optimum recording power is determined.

  The RF signal when reproducing the recording marks 111 and 112 recorded in this way, and the binarized signal based on the RF signal are as shown in FIG. 4A, and when the recording marks 111 and 112 are recorded. The same length can be used for playback in the same way.

  FIG. 4B shows a case where two recording marks 111 and 112 having the same recording length as those in FIG. 4A already recorded are overwritten, and the recording mark 221 is already recorded. In this case, the recording mark 111 is recorded from the middle, and the recording mark 222 is recorded at the same position as the recording mark 112 already recorded. Since the recording mark 222 is recorded at the same position as the recording mark 112 that has already been recorded, the recording of the recording mark 222 is equivalent to the case where recording is first performed on the unused optical disk 21. Further, since the recording mark 221 is recorded from the middle of the already recorded recording mark 111, it is necessary to newly record the recording mark 221 while erasing the already recorded recording mark 111.

  When the recording mark 221 is recorded from the middle of the already recorded recording mark 111, the recording power for recording the recording power 111, 112 is recorded, and the recording marks 221, 222, 231, 232 recorded later are recorded. As different from the recording power, the recording power for recording the recording powers 111 and 112 is set to be smaller than the recording power for recording the recording marks 221, 222, 231 and 232 to be recorded later. Compared to the conventional case where the first and second and subsequent data recording times are recorded with the same recording power, the erasure of the recording mark 111 can be made closer to an ideal state.

  This is because the recording power for recording the recording marks 221, 222, 231, and 232 is larger than the recording power for recording the recording marks 111 and 112 that have already been recorded. This is because the recording mark 111 can be erased more reliably.

  FIG. 4B shows an RF signal when reproducing the recording marks 221 and 222 recorded in this way, and a binarized signal based on the RF signal. The recording mark 221 recorded from the middle of the already recorded recording mark 111 and the recording mark 222 recorded at the same position as the already recorded recording mark 112 are compared with the conventional case shown in FIG. As a result, the offset amount when reproduced is reduced, and the difference between the two binarized data is also reduced.

  FIG. 4 (c) shows a case where two recording marks 231 and 232 having the same recording length as those in FIG. 4 (b) which have already been recorded are overwritten and recorded. The case of recording from the middle of the recorded recording marks 221 and 222 is shown. Since the recording marks 231 and 232 are recorded from the middle of the already recorded recording marks 221 and 222, new recording marks 231 and 232 are recorded while erasing the recording marks 221 and 222 already recorded. There is a need to. In this case, the RF signal for reproducing the recording marks 231 and 232 recorded in this way and the binarized signal based on the RF signal are as shown in FIG. 231 and 232 can be reproduced with the same length.

  This is because the unused portion of the recording surface of the optical disc 21 decreases after the third time of data recording of the optical disc 21 to be used, and is recorded when the data recording count of the optical disc 21 to be used is the first time and the second time. This is because the recording mark is not easily affected by the recording mark.

  In the present embodiment, the recording power for recording the recording marks 111 and 112 is 85 to 95% of the recording power for recording the recording marks 221, 222, 231 and 232 recorded later. However, the present invention is not limited to this. Considering that the number of data recording times of the optical disc 21 to be used efficiently improves the recording quality of the second time, the recording power for recording the recording marks 111 and 112 is set to the recording marks 221, 222, 231 and 232 recorded later. The recording power is preferably 85 to 95% of the recording power.

  Next, recording quality in an embodiment of the present invention will be described.

  FIG. 5 is a diagram showing the number of data recordings and the error rate in the optical disk recording method according to one embodiment of the present invention, where the horizontal axis represents the number of recordings and the vertical axis represents the error rate. FIG. 6 is a diagram showing the number of times of recording and jitter in the conventional optical disc recording method, wherein the horizontal axis shows the number of times of recording and the vertical axis shows the jitter.

  As shown in FIG. 9B, when the recording marks 221 and 222 having the same length are recorded but cannot be reproduced as the recording marks 221 and 222 having the same length at the time of reproduction, FIG. 10 and FIG. As shown, the recording quality deteriorates such that the data recording frequency of the optical disk 21 to be used has a peak at the second time. For example, the error rate is about 50 cps (pieces / second) when the number of times of data recording on the optical disc 21 to be used is the second time, and the jitter is 37 ns (when the number of times of data recording of the optical disc 21 to be used is the second time). Nanosecond).

  However, in the present embodiment, by using the above-described method, the error rate shown in FIG. 5 can be about 20 cps when the number of times of data recording on the optical disk 21 to be used is the second time. In addition, the jitter shown in FIG. 6 can be about 30 ns when the number of times of data recording on the optical disk 21 to be used is the second time.

  As described above, the recording power for recording data on the optical disc 21 is switched according to the number of times of data recording on the rewritable optical disc 21 to be used, so that the optimum recording power is set according to the recording situation of the rewritable optical disc 21. be able to.

  Therefore, the overwrite recording quality of the rewritable optical disc 21 can be improved, and an optical disc recording method and an optical disc apparatus capable of reducing the probability of recording failure can be realized.

  It is assumed that the number of times of data recording of the rewritable optical disc 21 to be used, which becomes the basis for switching the recording power for recording data, includes zero.

  Further, by adding an identifier to the test writing area 302a during the OPC operation, it is possible to grasp the number of data recording times of the rewritable optical disc 21 to be used, and the recording power can be changed depending on the number of recording times.

  The present invention can improve the overwrite recording quality of a rewritable optical disk and can reduce the probability of recording failure. Therefore, an optical disk recording method and an optical disk for recording data on an optical disk by an optical pickup are provided. It can be applied to devices.

1 is a block diagram of an optical pickup control unit of an optical disc apparatus according to an embodiment of the present invention. The figure which shows the data recording area structure of a CD-RW disc The flowchart which shows the optical disk recording method in one embodiment of this invention The figure which shows the relationship between the recording waveform of the optical disk recording method in one embodiment of this invention, and the recording mark on an optical disk surface The figure which shows the data recording frequency | count and error rate of the optical disk recording method in one embodiment of this invention The figure which shows the frequency | count of recording and jitter in the conventional optical disk recording method Block diagram of optical pickup control unit in conventional optical disc apparatus A flowchart showing a conventional optical disc recording method The figure which shows the relationship between the recording waveform in the conventional optical disk recording method, and the recording mark on an optical disk surface The figure which shows the recording frequency and error rate of the optical disk in the conventional optical disk recording method The figure which shows the recording frequency and jitter of an optical disk in the conventional optical disk recording method

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Laser diode 2 Optical pick-up 3 Light receiving means 4 Photodiode 5 Motor driver means 6 Laser driver means 7 Servo signal generation means 8 Analog signal generation means 9 Recording pattern generation means 10 Laser power control means 11 A / D converter 12 Controller 13 ROM
14 RAM
15, 16 Storage unit 21 Optical disk 22 Spindle motor 101 Recording pulse 111, 112 Recording mark 201 Recording pulse 202 Recording track 211, 212 Recording mark 221, 222 Recording mark 231, 232 Recording mark 301 Central hole 302 Non-user data recording area 302a Trial Writing area (PCA area)
302b Data management area (PMA area)
302c Lead-in area (LeadIn area)
303 User data recording area 501 Laser diode 502 Optical pickup 503 Light receiving means 504 Photo diode 505 Motor driver means 506 Laser driver means 507 Servo signal generating means 508 Analog signal generating means 509 Recording pattern generating means 510 Laser power control means 511 A / D converter 512 controller 513 ROM
514 RAM
515 storage unit

Claims (2)

A light source that emits laser light;
An optical pickup for recording data on a rewritable optical disk by the laser beam;
Current supply means for supplying current to the light source;
Laser power control means for operating the current supply means to control the recording power of the optical pickup;
And determining means for determining the recording power of the optical pickup,
The control means makes the recording power for the first recording on the rewritable optical disc smaller than the recording power for the second and subsequent recordings on the rewritable optical disc, and further moves the optical pickup. The presence or absence of data or signals in the test writing area, data management area, and lead-in area, which are non-user data recording areas of the rewritable optical disc, is checked. It is determined that the recording is the first recording on the rewritable optical disc, and if there is at least one of the data or the signal, it is determined that the recording is performed for the second time or later on the rewritable optical disc, and the non-user data recording area In the detection of data or signals, the trial writing area, the data area, the previous Performs detection operation in the order of the lead-in area, the optical disk apparatus characterized by immediately the rewritable optical disk if there is data in the trial writing region is determined to record the second and subsequent. An optical disk recording method for recording on a rewritable optical disk by changing the recording power of an optical pickup,
The recording power for the first recording on the rewritable optical disk is made smaller than the recording power for the second and subsequent recordings on the rewritable optical disk, and the rewritable optical disk is recorded first. When determining whether or not there is any data or signal in the test writing area, data management area and lead-in area which are non-user data recording areas of the rewritable optical disc, If there is not, it is determined as the first recording on the rewritable optical disc, and if there is at least one of the data or the signal, it is determined that the recording is performed for the second time or later on the rewritable optical disc,
Further, in the detection of data or signals in the non-user data recording area, a detection operation is performed in the order of the test writing area, the data area, and the lead-in area, and if the data exists in the test writing area, the rewriting is performed immediately. An optical disc recording method, wherein the type optical disc is determined to be a second or subsequent recording.

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