JP2008186508A - Optical disk device and optical disk recording and reproducing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical disk device having a low error rate by precise tilt adjustment and a superior read function. <P>SOLUTION: The optical disk device includes: moving means (S101, S119) moving the position of a beam spot in a radial direction of the optical disk; determination means (S103, S107, S109) determining whether the position of the beam spot on the optical disk is in a recorded region, an unrecorded region, or a boundary region between the recorded and unrecorded regions; and tilt adjustment means (S105, S108, S115) performing tilt adjustment using an RF amplitude and a PP amplitude when the determination means determine that it is in the recorded region and performing tilt adjustment using the PP amplitude when the determination means determine that it is in the unrecorded region. When the determination means determine that it is in the boundary region, the moving means move the position of the beam spot to the recorded region, and the tilt adjustment means perform the tilt adjustment using the RF amplitude. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an optical disc apparatus and an optical disc recording / reproducing method in which recording and reproducing performance is improved by performing tilt correction.

  An optical disk is generally formed in a disc shape, but is not completely flat but slightly warped slightly due to variations. When performing playback processing or recording processing of an optical disc in an optical disc apparatus, noise and jitter (ratio of deviation from the playback clock when the data playback signal is binarized) increase due to warpage and surface wobbling of the optical disc. There was a fear.

  For this reason, in the optical disc apparatus, tilt adjustment for adjusting the tilt of the objective lens and the like is performed in order to avoid such increase in noise and increase in jitter.

For example, in Patent Document 1, when the tilt correction value of an optical disk is obtained, a reproduction signal (RF) is used when the optical disk has been recorded, and a push-pull signal (PP) is used when the optical disk has not been recorded. A method for obtaining a tilt correction amount at a radius position is described.
JP 2006-196100 A

  Some recorded optical discs have a recorded area partway through and an unrecorded part from the middle, and those with an unrecorded area between recorded areas. If it is determined that such an optical disc has been recorded, there is a possibility that tilt adjustment will be performed using an RF signal in an unrecorded area. In this case, an accurate tilt correction amount cannot be obtained. It was.

  In addition, when an optical disc having an unrecorded area between recorded areas is erroneously determined to be unrecorded, the amplitude of the push-pull signal is recorded / unrecorded if the tilt adjustment point is at the recorded / unrecorded boundary. There was also a problem that due to the difference in the reflectance of the recording, the amplitude fluctuated due to factors other than the tilt amount, and accurate measurement was impossible.

  Further, when the tilt correction amount is obtained at a predetermined radial position, some optical discs do not even have a recording film after a certain radial position. In such an optical disc, the amplitude cannot be measured. There was also a problem that a correction amount could not be obtained.

  In addition, there is a problem that an accurate tilt correction amount cannot be obtained for an optical disc that is locally warped only at the outer periphery.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide an optical disc apparatus and an optical disc recording / reproducing method excellent in reading function by performing an accurate tilt adjustment to reduce an error rate.

  In order to solve the above problems, an optical disc apparatus according to the present invention includes a moving means for moving the position of a beam spot in the radial direction of the optical disc, and whether the position of the beam spot on the optical disc is in a recorded area, When it is determined by the determination means that it is in the unrecorded area or in the recorded and unrecorded boundary area, and the determination means determines that it is in the recorded area, the RF amplitude and PP amplitude are And a tilt adjustment unit that performs a tilt adjustment using a PP amplitude when the determination unit determines that it is in an unrecorded area. If it is determined, the moving means moves the position of the beam spot to a recorded area, and the tilt adjusting means performs tilt adjustment using RF amplitude. That.

  Also, in the optical disc recording / reproducing method according to the present invention, whether the position of the beam spot on the optical disc is in a recorded region, an unrecorded region, or a recorded and unrecorded boundary region. If it is determined in the area determining step and the recorded area in the area determining step, tilt adjustment is performed using the RF amplitude and the PP amplitude, and the unrecorded area is determined in the area determining step. If it is determined that there is a tilt adjustment using the PP amplitude, and if it is determined in the boundary determination step in the region determination step, the position of the beam spot is moved to the recorded region. And a tilt adjustment step of performing a tilt adjustment using the RF amplitude.

  According to the present invention, it is possible to provide an optical disc apparatus and an optical disc recording / reproducing method with improved recording and reproducing performance by performing tilt correction to reduce the error rate.

  Embodiments of an optical disc apparatus and an optical disc recording / reproducing method according to the present invention will be described with reference to the accompanying drawings.

  Note that the optical disc 2 that is the target of the recording process or the reproducing process of the optical disc apparatus and the optical disc recording / reproducing method according to the present invention can record a read-only optical disc such as a DVD-ROM or user data such as a DVD-R It is an optical disk.

  FIG. 1 shows a configuration diagram of an optical disc apparatus 1 according to the present invention.

  In the optical disc apparatus 1, the optical disc 2 is rotationally driven by a disc motor 3. The disk motor 3 is controlled by a disk motor control circuit 4.

  Information recording processing and reproduction processing with respect to the optical disc 2 in the optical disc apparatus 1 are performed by the optical pickup 5. The optical pickup 5 is provided with an objective lens 6 movably supported by a wire or a leaf spring (not shown). The objective lens 6 is driven in the focusing direction (the optical axis of the lens) by driving a focus direction driving coil 7. ) And can be moved in the tracking direction (direction perpendicular to the optical axis of the lens) by driving the track direction drive coil 8.

  The modulation circuit 9 modulates user data supplied from the host device 28 via the interface circuit 27 during information recording, and supplies the modulated recording data to the laser control circuit 10. The modulation method is, for example, 8-16 modulation in the case of a DVD system, and EFM modulation in the case of a CD system.

  The laser control circuit 10 sends a write signal to the semiconductor laser diode 11 in the optical pickup 5 based on the modulated recording data supplied from the modulation circuit 9 when information is recorded on the optical disc 2 (at the time of mark formation). Supply.

  The semiconductor laser diode 11 generates laser light in accordance with a signal supplied from the laser control circuit 10. Laser light emitted from the semiconductor laser diode 11 is irradiated onto the recording or reproducing surface of the optical disc 2 through the optical system component 12 and the objective lens 6. The reflected light from the optical disk 2 passes through the objective lens 6 and the optical system component 12 and is guided to the photodetector 13 in the optical pickup 5. An output signal from the photodetector 13 is supplied to the signal processing circuit 14.

  The signal processing circuit 14 generates a focus error signal (FE signal) and outputs the generated focus error signal to the focusing control circuit 15. The focusing control circuit 15 generates a focusing control signal based on the focus error signal input from the signal processing circuit 14 and supplies the generated focusing control signal to the focus direction drive coil 7 of the optical pickup 5. As a result, the objective lens 6 is controlled so that the laser light is always just focused on the information recording surface of the optical disc 2.

  In addition, the signal processing circuit 14 generates a tracking error signal (TE signal) and outputs the generated tracking error signal to the tracking control circuit 16. The tracking control circuit 16 generates a tracking control signal based on the tracking error signal input from the signal processing circuit 14, and supplies the generated tracking control signal to the track direction drive coil 8 of the optical pickup 5. Thereby, the objective lens 6 is controlled so that the laser light follows the track on the information recording surface of the optical disc 2.

  The signal of the tracking control circuit 16 is supplied to the sled motor control circuit 17. When the objective lens 6 is controlled by the tracking control circuit 16, the sled motor control circuit 17 controls the sled motor 18 so that the objective lens 6 is positioned in the vicinity of the center position in the optical pickup 5. 5 is controlled in the radial direction.

  The signal processing circuit 14 generates a data reproduction signal (RF signal) from the output signal of the photodetector 13 and outputs the generated data reproduction signal to the data reproduction circuit 19. The data reproduction circuit 19 demodulates the recording data using the data reproduction signal input from the signal processing circuit 14 based on the reproduction clock signal from the PLL circuit 20. The reproduction data demodulated by the data reproduction circuit 19 is error-corrected by an error correction circuit (not shown) using the assigned error correction code, and then output to the host device 28 via the interface circuit 27. The signal processing circuit 14 has a function as signal processing means.

  Here, the optical disc 2 is formed in a disc shape as a whole, but is not completely a flat plate, and as shown in FIG. When the information recording surface of the optical disk 2 is tilted with respect to the optical axis of the laser light passing through the objective lens 6 of the optical pickup 5 due to the warp or surface vibration of the optical disk 2, the wavefront aberration of the laser light increases. End up. For this reason, the magnitude of the data reproduction signal (RF signal) and the focus error signal (FE signal) generated by the signal processing circuit 14 based on the output signal of the photodetector 13 is reduced, and noise is relatively increased. Jitter (ratio of deviation from the reproduction clock when the data reproduction signal is binarized) also increases.

  Therefore, in order to avoid such an increase in noise and an increase in jitter, the optical disc apparatus 1 is provided with a tilt mechanism 21 for adjusting the tilt of the objective lens 6, that is, for adjusting the tilt. The tilt mechanism 21 is mounted at a predetermined position of the optical pickup 5.

  FIG. 2 shows an example of tilt adjustment positions (tilt adjustment positions 0, 1, 2,..., N−1, N) on the optical disc 2. As shown in FIG. 2, the warp in the optical disc 2 may increase as it approaches the outer peripheral side, so the distance (interval) between adjacent tilt adjustment positions as the optical disc 2 approaches the outer peripheral side from the inner peripheral side. Is set to be narrower.

  When tilt adjustment is performed, the tilt control circuit 22 controls the tilt mechanism 21 according to the magnitude of the RF signal obtained from the signal processing circuit 14 at these tilt adjustment positions, so that the tilt of the information recording surface of the optical disc 2 is controlled. The optical axis of the lens 6 is tilted to an appropriate value.

  The disk motor control circuit 4, thread motor control circuit 17, modulation circuit 9, laser control circuit 10, focusing control circuit 15, tracking control circuit 16, data reproduction circuit 19, PLL circuit 20, tilt control circuit 22 and the like are servo control circuits. Can be configured in one LSI chip. These circuits are controlled by a CPU (Central Processing Unit) 24 via a bus 23.

  The CPU 24 follows an operation command supplied from the host device 28 via the interface circuit 27 and follows a program stored in a ROM (Read Only Memory) 26 and a program loaded from the ROM 26 to a RAM (Random Access Memory) 25. Various processes are executed, various control signals are generated, and are supplied to the respective units, whereby the optical disc apparatus 1 is comprehensively controlled.

  When the tilt adjustment is performed in the optical disc apparatus 1, the tilt of the optical disc 2 is tilted using the top envelope signal of the RF signal (hereinafter referred to as RF amplitude) and the amplitude of the push-pull signal (hereinafter referred to as PP amplitude). A correction amount is calculated, and this tilt correction amount is reflected according to each radial position. That is, in the optical disc apparatus 1, tilt adjustment is performed by operating the tilt mechanism 21 based on this tilt correction amount.

  In a general optical disc apparatus 1, the smaller the error rate in the information read from the optical disc 2, that is, the error rate, the better. Therefore, the optical disc apparatus 1 calculates the tilt correction amount using the RF amplitude and PP amplitude correlated with the error rate.

  FIG. 3 shows the correlation of the RF amplitude and PP amplitude with respect to the error rate. FIG. 4 shows the measurement variation of the RF amplitude when the tilt is changed by the tilt mechanism 21, and FIG. 5 shows the measurement variation of the PP amplitude when the tilt is changed by the tilt mechanism 21. 4 and 5, it can be seen that the RF amplitude has a smaller variation than the PP amplitude, and the measurement result is stable.

  Therefore, in the optical disc apparatus 1, when the tilt adjustment position is in a recorded area where the RF signal can be acquired, the tilt adjustment is performed using the RF amplitude and the PP amplitude, and the tilt adjustment position cannot acquire the RF signal. If it is in the region, tilt adjustment is performed using only the PP amplitude.

  A first embodiment of an optical disc apparatus 1 and an optical disc recording / reproducing method according to the present invention will be described with reference to FIGS.

  First, a procedure for performing tilt adjustment processing during disc recognition processing in the optical disc apparatus 1 will be described with reference to the flowchart shown in FIG. Hereinafter, for example, “step S101” is described as “S101”, and “step” is omitted.

  If the amplitude of each signal is unstable, the CPU 24 performs amplitude adjustment so that the amplitude of the signal becomes a constant value before performing tilt adjustment in the optical disc apparatus 1. Further, the tilt adjustment is performed at (N + 1) positions of the tilt adjustment positions 0, 1,.

  First, the CPU 24 moves the optical pickup so that the beam spot hits the tilt adjustment position 0 shown in FIG. 2 (S101). The CPU 24 determines whether or not the optical disc 2 to be tilt-adjusted is a reproduction-only disc such as a DVD-ROM (S103). If the optical disk 2 is a reproduction-only disk (Yes in S103), it is known that the tilt adjustment position is a recorded area, so that the tilt adjustment is performed using the RF amplitude (S105).

  When the CPU 24 calculates the tilt correction amount, the value obtained by measuring the RF signal for one rotation of the disk with the tracking servo turned off is used as an average value, and this measurement is performed a plurality of times while changing the tilt amount by a certain amount. The tilt correction amount that maximizes the amplitude (maximum point) is obtained by approximating the results of these measurements by the least square method.

  If the optical disk 2 is not a reproduction-only disk (No in S103), the CPU 24 determines whether or not the tilt adjustment position is in the recorded area by determining the unrecorded boundary (area determination). (S107).

  In the recording / unrecorded boundary determination, as shown in FIG. 7, a signal indicating the presence or absence of an RF signal is used, and the duty of the signal is measured for one rotation of the disk with the tracking servo turned off. The CPU 24 performs the same measurement by moving the optical pickup to the inner peripheral side by a distance of an eccentric amount twice as large as that of the optical disc 2 (difference between the center of gravity of the optical disc 2 and the rotation center) from the adjustment position. Further, the CPU 24 moves the optical pickup to the outer peripheral side by a distance corresponding to the eccentric amount twice as large as that of the optical disk 2 from the adjustment position as a center, and performs the same measurement. As shown in FIG. 8, in the optical disc 2, the recorded area, the unrecorded area, and the boundary area can be determined based on the duty value. Therefore, for example, the CPU 24 records when the duty of all three points is equal to or greater than the predetermined value A, records not when the duty is equal to or smaller than the predetermined value B, and is between the predetermined value A and the predetermined value B. Judge as a boundary.

  When the tilt adjustment position is in the recorded area (Yes in S107), the CPU 24 performs tilt adjustment using the RF amplitude and the PP amplitude (S108).

  The CPU 24 determines whether or not the tilt adjustment position is at the boundary between the recorded area and the unrecorded area (S109). When it is determined that the tilt adjustment position is at the boundary between the recorded area and the unrecorded area (Yes in S109), the CPU 24 moves the optical pickup to the inner peripheral side by a predetermined distance as shown in FIG. Move (S111). The CPU 24 again determines whether or not the position is in the recorded area by determining the unrecorded boundary in S107 (S113). If the position is not a recorded area (No in S113), the CPU 24 returns to S109 again and determines whether the boundary is an unrecorded boundary. If it is also a boundary here (Yes in S109), the processing of S111 and S113 is performed.

  If the position is a recorded area (Yes in S113), the CPU 24 performs tilt adjustment using the RF amplitude and the PP amplitude at this position.

  If it is determined that the tilt adjustment position is not at the boundary between the recorded area and the unrecorded area (No in S109), the CPU 24 uses the PP amplitude because the tilt adjustment position is in the unrecorded area. Tilt adjustment is performed (S115).

  The CPU 24 determines whether (N + 1) times of tilt adjustment has been performed, that is, whether tilt adjustment at the tilt adjustment position N has been performed (S117). When (N + 1) times of tilt adjustment has not been performed (No in S117), the CPU 24 moves the optical pickup so that the beam spot hits a tilt adjustment position close to the outer peripheral side of the optical disc 2 (S119). Then, the CPU 24 performs the processes from S103 to S117 again.

  When (N + 1) times of tilt adjustment has been performed (Yes in S117), the CPU 24 moves the optical pickup to the initial position (S121).

  In this way, in the optical disc apparatus 1, tilt adjustment processing is performed during disc recognition processing.

  Next, the procedure for performing the tilt adjustment process during the recording process in the optical disc apparatus 1 will be described based on the flowchart shown in FIG.

  First, the CPU 24 starts an OPC (Optimum Power Control) process in order to perform a recording process on the optical disc 2 (S201). OPC is a function for adjusting the laser power to an optimum level according to the surface state of the optical disk 2 during the recording process. The optical disk 2 is provided with an OPC area that is an area for performing the OPC process in advance.

  The CPU 24 creates a recording area for tilt adjustment in the OPC area of the optical disc 2 (S203). As shown in FIG. 11, the recording area is at least one area of the optical disk 2. Further, the CPU 24 obtains a tilt correction amount using the RF amplitude in the recording area created in S203 and performs tilt adjustment (S205).

  Then, the CPU 24 starts a recording process on the optical disc 2 (S207). The CPU 24 determines whether or not the position where the recording process is performed has reached the tilt adjustment position (S213). When the tilt adjustment position has not been reached (No in S213), the CPU 24 continues the recording process (S214) and returns to S213. When the tilt adjustment position is reached (Yes in S213), the CPU 24 moves the optical pickup by a predetermined distance in the direction opposite to the recording direction as shown in FIG. 12 (S215). The amount of movement at this time is set such that the unrecorded area is not irradiated with the laser of the optical pickup due to eccentricity.

  The CPU 24 determines whether or not the position moved in S215 is a recorded area (S217). If it is not a recorded area (No in S217), the CPU 24 returns to the position where the original recording process was performed, continues (restarts) the recording process (S214), and returns to S213. If the area has been recorded (Yes in S217), the CPU 24 performs tilt adjustment using the RF amplitude at this position (S219).

  Then, the CPU 24 determines whether or not the recording process on the optical disc 2 has been completed (S221). If the recording process has not ended (No in S221), the CPU 24 continues the recording process (S214) and returns to S213. When the recording process is finished (Yes in S221), the CPU 24 finishes the tilt adjustment process.

  As described above, in the optical disc apparatus 1, when the recording process reaches the tilt adjustment position, the recording operation is temporarily stopped, the optical pickup is moved to the area where the recording process has been performed immediately before, and the tilt using the RF amplitude is further performed. Adjustments are being made.

  According to the first embodiment of the optical disc apparatus 1 and the optical disc recording / reproducing method according to the present invention, the tilt correction accuracy can be improved by performing the tilt adjustment using the RF amplitude during the recording process. It has become possible.

  Further, according to Embodiment 1 of the optical disc apparatus 1 and the optical disc recording / reproducing method according to the present invention, it is possible to improve the reading function by reducing the error rate by performing an accurate tilt adjustment.

  The processes in steps S101, S119, and S215 are moving means, the processes in steps S103, S107, and S109 are area determining means, the processes in steps S105, S115, and S219 are tilt adjusting means, and the process in S213. Is position determination means.

  A second embodiment of the optical disc apparatus and the optical disc recording / reproducing method according to the present invention will be described with reference to FIGS.

  A procedure for performing tilt adjustment processing when the optical disc apparatus 1 performs recording processing on the optical disc 2 will be described with reference to the flowcharts shown in FIGS.

  First, the CPU 24 starts an OPC process in order to perform a recording process on the optical disc 2 (S301). The CPU 24 creates a recording area for tilt adjustment on the optical disc 2 (S303). Further, the CPU 24 obtains a tilt correction amount using the RF amplitude in the recording area created in S303 and performs tilt adjustment (S305).

  The CPU 24 calculates the difference between the tilt correction amount obtained using the RF amplitude in S305 and the tilt correction amount obtained using the PP amplitude at the tilt adjustment position 0 in S115 of FIG. 6 as an OPC offset ( S307). The CPU 24 stores the OPC offset in the ROM 26 (S309).

  In the optical disc apparatus 1, when the tilt adjustment is performed during the recording process on the optical disc 2, the position where the recording process is currently performed is an unrecorded area, and therefore the tilt correction is performed using only the PP amplitude. Will do. When tilt correction is performed using only the PP amplitude, measurement variation increases as shown in FIG. 5, and there is a possibility that highly accurate tilt correction cannot be performed. Therefore, in order to correct the measurement error during the recording process, the CPU 24 stores the OPC offset in S309.

  Then, the CPU 24 starts a recording process on the optical disc 2 (S311). Here, the CPU 24 calculates a tilt correction amount and performs a reflection process for operating the tilt mechanism 21 based on the tilt correction amount (S313). In this reflection process, the adjustment result obtained by performing the tilt adjustment using the RF amplitude is more accurate than the adjustment result obtained by performing the tilt adjustment using the PP amplitude. Therefore, the adjustment performed by performing the tilt adjustment using the RF amplitude as much as possible. Tilt adjustment is made so that the result is taken into account. This reflection process will be described based on the flowchart shown in FIG.

  The CPU 24 calculates the radial position on the optical disc 2 where the light is hit by the optical pickup (S401). The CPU 24 determines whether or not there are two tilt adjustment positions so as to sandwich the radius position calculated in S401 (S403). That is, it is determined that there are no two tilt adjustment positions only when the radial position is on the inner circumference side from the tilt adjustment position 0 in FIG. 2 and on the outer circumference side from the tilt adjustment position N in FIG.

  If it is determined that there are two tilt adjustment positions (Yes in S403), the CPU 24 has a tilt adjustment result using RF amplitude at both of the two tilt adjustment positions adjacent to both sides at this radial position. Whether or not (S405).

  When it is determined that there is no tilt adjustment result using the RF amplitude at both tilt adjustment positions (No in S405), the CPU 24 determines two tilts adjacent to both sides at the radial position calculated in S401. It is determined whether there is a tilt adjustment result using the RF amplitude at any of the adjustment positions (S407).

  If there is a tilt adjustment result using the RF amplitude at any of the tilt adjustment positions (Yes in S407), the CPU 24 performs the tilt adjustment using the PP amplitude, and performs linear interpolation using the PP amplitude adjustment result. The value obtained by adding the difference between the tilt adjustment result using the RF amplitude at one adjacent tilt adjustment position and the investigation result using this PP amplitude to the value obtained is set as the tilt correction amount (S409). Then, the CPU 24 operates the tilt mechanism 21 by the tilt correction amount obtained in S409 (S411).

  When it is determined that there is a tilt adjustment result using the RF amplitude at both tilt adjustment positions (Yes in S405), the CPU 24 displays the tilt adjustment result using the RF amplitude at both the tilt adjustment positions. The value linearly interpolated using this is set as the tilt correction amount (S413). Then, the CPU 24 operates the tilt mechanism 21 by the tilt correction amount obtained in S413 (S411).

  If there is no tilt adjustment result using the RF amplitude at any tilt adjustment position (No in S407), the CPU 24 performs tilt adjustment using the PP amplitude, and performs linear interpolation using the PP amplitude adjustment result. A value obtained by adding the OPC offset stored in the ROM 26 in S309 to the obtained value is set as a tilt correction amount (S415). Then, the CPU 24 operates the tilt mechanism 21 by the tilt correction amount obtained in S415 (S411).

  If it is determined that there are no two tilt adjustment positions at the radius position calculated in S401 (No in S403), the CPU 24 uses the RF amplitude at a nearby tilt adjustment position even if it is not adjacent. Then, it is determined whether or not there is an adjustment result obtained by performing the tilt adjustment (S417).

  When there is an adjustment result obtained by performing the tilt adjustment using the RF amplitude at a nearby tilt adjustment position (Yes in S417), the CPU 24 uses the tilt adjustment result using the RF amplitude at the tilt adjustment position as the tilt correction amount. (S418). Then, the CPU 24 operates the tilt mechanism 21 by the tilt correction amount obtained in S418 (S411).

  If there is no adjustment result obtained by performing the tilt adjustment using the RF amplitude at a nearby tilt adjustment position (No in S417), the CPU 24 stores the PP amplitude adjustment result performed at the time of disc recognition in the ROM 26 in S309. A value obtained by adding the OPC offset is set as a tilt correction amount (S415). Then, the CPU 24 operates the tilt mechanism 21 by the tilt correction amount obtained in S415 (S411).

  When finishing the reflection process of S401 to S415, the CPU 24 determines whether or not the position where the recording process is performed has reached the tilt adjustment position (S315). If the tilt adjustment position has not been reached (No in S315), the CPU 24 continues the recording process (S316) and returns to S313. When the tilt adjustment position has been reached (Yes in S315), the CPU 24 moves the optical pickup by a predetermined distance in the direction opposite to the recording direction as shown in FIG. 12 (S317). The amount of movement at this time is set such that the unrecorded area is not irradiated with the laser of the optical pickup due to eccentricity.

  The CPU 24 determines whether or not the position moved in S215 is a recorded area (S319). If it is not a recorded area (No in S319), the CPU 24 returns to the position where the original recording process was performed, continues (restarts) the recording process (S316), and returns to S313. If it is a recorded area (Yes in S319), the CPU 24 performs tilt adjustment using the RF amplitude at this position (S321).

  Then, the CPU 24 determines whether or not the recording process on the optical disc 2 has been completed (S323). If the recording process has not ended (No in S323), the CPU 24 continues the recording process (S316) and returns to S313. When the recording process is finished (Yes in S323), the CPU 24 finishes the tilt adjustment process.

  In the second embodiment, the example in which the tilt adjustment process is performed while the recording process is performed in the optical disc apparatus 1 has been described. However, the present invention is not limited to this, and the same applies when the reproduction process is performed in the optical disc apparatus 1. Tilt adjustment processing can be performed. At this time, in step S415, the value obtained by performing linear interpolation using the PP amplitude adjustment result without adding the OPC offset stored in the ROM 26 in step S309 is set as the tilt correction amount.

  Note that the processing in step S309 is storage means, the processing in step S317 is movement means, the processing in steps S321, S409, S411, S413, and S415 is tilt adjustment means, and the processing in S315 is position determination means. , Steps S403, S405, S407, and S417 are correction amount presence / absence judging means.

  According to the second embodiment of the optical disc apparatus 1 and the optical disc recording / reproducing method according to the present invention, there is a tilt correction amount using the RF amplitude in both of the two tilt adjustment positions sandwiching the radial position where the current recording process is performed. In this case, the RF amplitude adjustment result is linearly interpolated. If both have only the result using the PP amplitude, the PP amplitude adjustment result is linearly interpolated. If there is a result using the RF amplitude in one of the results, the PP amplitude A value obtained by adding the difference between the RF amplitude adjustment result and the PP amplitude adjustment result as an offset to the linearly interpolated adjustment result is obtained according to the radial position, and is used as a tilt correction amount, thereby supporting the reproduction process and the recording process. It became possible to perform tilt adjustment with high accuracy.

  Further, according to Embodiment 2 of the optical disc apparatus 1 and the optical disc recording / reproducing method according to the present invention, it is possible to improve the reading function by reducing the error rate by performing an accurate tilt adjustment.

  The series of processes described in the embodiments of the present invention can be executed by software, but can also be executed by hardware.

  Furthermore, in the embodiment of the present invention, the steps of the flowchart show an example of processing performed in time series in the order described, but parallel or individual execution is not necessarily performed in time series. The processing to be performed is also included.

1 is a configuration diagram of an optical disc apparatus according to the present invention. The figure for demonstrating the tilt adjustment position in the optical disk apparatus concerning this invention. The figure which shows the correlation with respect to the error rate of RF signal and PP signal in the optical disk apparatus based on this invention. The figure which shows the dispersion | variation in RF signal in the optical disk apparatus based on this invention. The figure which shows the dispersion | variation in PP signal in the optical disk apparatus based on this invention. 9 is a flowchart showing a procedure for performing tilt adjustment processing when the optical disc apparatus according to the present invention performs optical disc recognition processing. The figure for demonstrating the recording unrecorded boundary determination of the optical disk by the optical disk apparatus based on this invention. The figure for demonstrating the recording unrecorded boundary determination of the optical disk by the optical disk device based on this invention. The figure for demonstrating the recording unrecorded boundary determination of the optical disk by the optical disk device based on this invention. 6 is a flowchart showing a procedure for performing tilt adjustment processing during OPC and recording processing by the optical disc apparatus according to the present invention. The figure for demonstrating the tilt adjustment process by the optical disk device based on this invention. The figure for demonstrating the tilt adjustment process by the optical disk device based on this invention. 5 is a flowchart showing a procedure for tilt adjustment processing performed by the optical disc apparatus according to the present invention during recording processing of the optical disc. 6 is a flowchart showing a procedure for performing a reflection process when an optical disk apparatus according to the present invention records an optical disk.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Optical disk apparatus, 2 ... Optical disk, 3 ... Disk motor, 4 ... Disk motor control circuit, 5 ... Optical pick-up, 6 ... Objective lens, 7 ... Focus direction drive coil, 8 ... Tracking direction drive coil, 9 ... Modulation circuit, DESCRIPTION OF SYMBOLS 10 ... Laser control circuit, 11 ... Semiconductor laser diode, 12 ... Optical system component, 13 ... Optical detector, 14 ... Signal processing circuit, 15 ... Focusing control circuit, 16 ... Tracking control circuit, 17 ... Thread motor control circuit, 18 DESCRIPTION OF SYMBOLS: Thread motor, 19 ... Data reproduction circuit, 20 ... PLL circuit, 21 ... Tilt mechanism, 22 ... Tilt control circuit, 23 ... Bus, 24 ... CPU24, 25 ... RAM, 26 ... ROM, 27 ... Interface circuit, 28 ... Host apparatus.

Claims (6)

Moving means for moving the position of the beam spot in the radial direction of the optical disc;
An area determination means for determining whether the position of the beam spot on the optical disc is in a recorded area, an unrecorded area, or a recorded and unrecorded boundary area;
When it is determined that the recorded area is in the recorded area by the area determining means, the tilt adjustment is performed using the RF amplitude and the PP amplitude. When the area determining means determines that the recorded area is in the unrecorded area, the PP is adjusted. A tilt adjusting means for performing tilt adjustment using the amplitude, and
When it is determined by the region determining unit that the region is in the boundary region, the moving unit moves the position of the beam spot to the recorded region, and the tilt adjusting unit performs tilt adjustment using the RF amplitude. An optical disc device characterized. The optical disc apparatus includes position determining means for determining whether or not a predetermined position has been reached,
During the recording process, when the position determining unit determines that the predetermined position has been reached, the moving unit moves the position of the beam spot to the recorded region, and the tilt adjusting unit The optical disk apparatus according to claim 1, wherein tilt adjustment is performed using the optical disk. The optical disc apparatus includes a correction amount presence / absence determination unit that determines whether there is a tilt correction amount obtained by performing tilt adjustment using the RF amplitude by the tilt adjustment unit in the vicinity during the recording process or the reproduction process. Prepared,
3. The optical disc apparatus according to claim 2, wherein when the correction amount presence / absence determining unit determines that there are a plurality of tilt correction amounts, the tilt adjusting unit reflects the tilt correction based on the tilt correction amounts.   When it is determined by the correction amount presence / absence determination means that there is a tilt correction amount obtained by performing tilt adjustment using a single RF amplitude, the tilt adjustment means uses the tilt correction amount and the PP amplitude. 4. The optical disc apparatus according to claim 3, wherein the tilt adjustment is performed based on the tilt correction amount at the current position obtained from the tilt correction amount obtained by performing the tilt adjustment. The optical disc apparatus uses the tilt correction amount obtained by the tilt adjustment using the RF amplitude during the OPC processing by the tilt adjustment unit, and similarly uses the PP amplitude at the innermost tilt adjustment position when the tilt adjustment unit recognizes the disc. Storage means for storing the difference from the tilt correction amount obtained by performing the tilt adjustment as an offset,
When it is determined that the tilt correction amount obtained by performing the tilt adjustment using the RF amplitude is not present by the correction amount presence / absence determination unit during the recording process, the tilt adjustment unit stores the offset stored in the storage unit. 5. The optical disc apparatus according to claim 4, wherein the tilt adjustment is performed based on the tilt correction amount at the current position obtained from the tilt correction amount obtained by performing the tilt correction using the PP amplitude. An area determination step for determining whether the position of the beam spot on the optical disc is in a recorded area, an unrecorded area, or a recorded and unrecorded boundary area;
If it is determined in the area determination step that the recorded area is present, tilt adjustment is performed using the RF amplitude and the PP amplitude, and if it is determined in the area determination step that the recording area is not yet recorded. , The tilt adjustment is performed using the PP amplitude, and if it is determined that the region is in the boundary region in the region determination step, the position of the beam spot is moved to the recorded region and then the tilt adjustment is performed using the RF amplitude. A tilt adjustment step for performing
An optical disc recording / reproducing method comprising:

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