JP2008034012A - Method for adjusting tilt, optical pickup adjustment mechanism, and optical disk device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for precisely adjusting tilts of an optical disk and an optical pickup, and to provide an optical pickup adjustment mechanism and an optical disk device therefor. <P>SOLUTION: The optical pickup adjustment mechanism 131 generates an RF signal based on reflected light photodetected from a data recording area of the optical disk (S103), performs rough adjustment of obtaining a tilt which maximizes the amplitude of the generated RF signal (S104), and varies the tilt in a fine range set in advance with the tilt obtained by the rough adjustment as a center to perform fine adjustment of obtaining a tilt which minimizes the number of errors of the RF signal (S105). <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  Tilt amount adjustment method for adjusting the tilt amount between an optical disc and an optical pickup that receives reflected light of light irradiated to the optical disc, an optical pickup adjustment mechanism to which the tilt amount adjustment method is applied, and the optical pickup adjustment mechanism In particular, the present invention relates to a tilt amount adjusting method, an optical pickup adjusting mechanism, and an optical disc apparatus capable of adjusting a tilt amount with high accuracy.

  Optical disc apparatuses such as DVD recorders and personal computers having a drive for recording and reading data on optical discs such as CD (Compact Disc) and DVD (Digital Versatile Disc) are widely used. Such an optical disk apparatus is provided with an optical pickup that irradiates the optical disk with a light beam and receives the reflected light. The optical disk apparatus is recorded on the optical disk based on the reflected light received by the optical pickup. Read data.

  However, the relative angle between the optical disk and the optical pickup may change due to factors such as warping of the optical disk, and the light beam may be tilted with respect to the information recording surface of the optical disk. When such a tilt of the light beam, that is, a so-called radial tilt, is large, the quality of the reproduced signal is deteriorated due to an increase in error of the read signal due to factors such as an increase in jitter. Therefore, an optical pickup adjusting mechanism such as a tilt servo for adjusting the tilt amount is provided in the optical disc apparatus.

In Patent Document 1, the tilt amount is corrected so that the amplitude of an RF (Radio Frequency) signal based on reflected light received from an area where data is recorded is maximized with respect to an optical disk on which data is recorded. Tilt amount so that the amplitude of an LPP (Land Pre-Pit) signal based on a pre-pit provided in an area called a land between recording grooves (grooves) for recording data is maximized with respect to an optical disc on which no data is recorded. A tilt correction method for correcting the above is disclosed.
JP 2004-95035 A

  However, depending on the state of the optical pickup and optical disk to be used, the point where the amplitude of the RF signal is maximized and the point where the amplitude of the LPP signal is maximized are not necessarily the best points where the error is minimized. However, there is no particular problem if the difference between the signal amplitude maximum and the best point is small relative to the jitter margin, but if the difference is large relative to the jitter margin, it cannot be ignored. It becomes.

  In addition, when the optical disk is scratched or dirty, the method for obtaining only the maximum signal amplitude point has a risk of detecting a position that is not the original best point as the best point, depending on the sampling method. .

  The present invention has been made in view of such circumstances, and after performing coarse adjustment based on the amplitude of the RF signal, fine adjustment is performed based on the error state of the RF signal, and light is received from the recording groove of the optical disc. The amount of tilt that can be adjusted with high accuracy by performing coarse adjustment based on the amplitude of the TE (Tracking Error) signal based on the reflected light and then performing fine adjustment based on the pre-pit detection status It is an object of the present invention to provide an adjustment method, an optical pickup adjustment mechanism to which the tilt amount adjustment method is applied, and an optical disc apparatus including the optical pickup adjustment mechanism.

  A tilt amount adjusting method according to a first aspect of the present invention is a tilt amount adjusting method for adjusting a tilt amount between an optical disc and an optical pickup that receives reflected light of light irradiated on the optical disc, wherein data on the optical disc is recorded. A waveform signal based on reflected light received from a certain area is generated, coarse adjustment is performed based on the amplitude of the generated waveform signal, and fine adjustment is performed based on an error condition of the waveform signal.

  In the present invention, after coarse adjustment is performed based on the amplitude of a waveform signal such as an RF signal, fine adjustment is performed based on an error situation, so that the position determined based on the amplitude of the waveform signal is the signal error ( Even if the position is not at a minimum, the fine adjustment is performed based on the error situation, so that the tilt amount can be adjusted with high accuracy. Moreover, it is not easily affected by scratches or dirt on the optical disk.

  The tilt amount adjusting method according to the second aspect of the present invention provides a tilt amount between an optical disc in which pre-pits are provided in advance along a recording groove for recording data and an optical pickup that receives reflected light of light irradiated on the optical disc. In the tilt amount adjustment method to be adjusted, a waveform signal based on the reflected light received from the recording groove is generated, coarse adjustment is performed based on the amplitude of the generated waveform signal, a prepit is detected, and a fine signal is detected based on the prepit detection status. Adjustment is performed.

  In the present invention, after performing coarse adjustment based on a waveform signal such as a TE signal, fine adjustment is performed based on the prepit detection status, so that the position determined based on the amplitude of the waveform signal is Even when the position is not the minimum, fine adjustment based on the pre-pit signal is performed, so that the tilt amount can be adjusted with high accuracy. Moreover, it is not easily affected by scratches or dirt on the optical disk.

  An optical pickup adjusting mechanism according to a third aspect of the present invention is an optical pickup adjusting mechanism that adjusts the tilt amount between an optical disc and an optical pickup that receives reflected light of light irradiated on the optical disc, in which data on the optical disc is recorded. Means for generating a waveform signal based on reflected light received from a certain area, coarse adjustment means for performing coarse adjustment based on the amplitude of the generated waveform signal, and fine adjustment means for performing fine adjustment based on an error condition of the waveform signal It is characterized by providing.

  In the present invention, after performing coarse adjustment based on the amplitude of a waveform signal such as an RF signal, fine adjustment is performed based on an error situation, so that the position determined based on the amplitude of the waveform signal is Even when the position is not at the minimum position, fine adjustment is performed based on the error situation, so that the tilt amount can be adjusted with high accuracy. Moreover, it is not easily affected by scratches or dirt on the optical disk.

  According to a fourth aspect of the present invention, there is provided the optical pickup adjustment mechanism according to the third aspect, wherein the waveform signal is an RF (Radio Frequency) signal, and the coarse adjustment means adjusts the tilt amount so that the amplitude of the waveform signal is maximized. The fine adjustment means is configured to adjust to a tilt amount that minimizes the number of errors.

  In the present invention, it is possible to detect the position where the S / N ratio is good and the error is difficult to occur by adjusting the tilt amount so that the amplitude is maximized, and the number of errors in a minute range including the detected position. By detecting the tilt amount at the position where the error is minimized, the tilt amount can be adjusted with high accuracy even when the position determined based on the amplitude of the waveform signal is not the position where the signal error is minimized. It is. In addition, it is possible to prevent the risk of misadjusting the tilt amount due to amplitude fluctuations due to scratches or dirt on the optical disk.

  An optical pickup adjustment mechanism according to a fifth aspect of the present invention provides a tilt amount between an optical disc in which prepits are provided in advance along a recording groove for recording data and an optical pickup that receives reflected light of light irradiated on the optical disc. In the optical pickup adjustment mechanism to adjust, means for generating a waveform signal based on the reflected light received from the recording groove, rough adjustment means for performing rough adjustment based on the amplitude of the generated waveform signal, means for detecting a prepit, And a fine adjustment means for performing fine adjustment based on a pre-pit detection state.

  In the present invention, after performing coarse adjustment based on a waveform signal such as a TE signal, fine adjustment is performed based on the detection state of the prepit, so that the position determined based on the amplitude of the waveform signal is Even when the position is not the minimum position, fine adjustment based on the pre-pit signal is performed, so that the tilt amount can be adjusted with high accuracy. Moreover, it is not easily affected by scratches or dirt on the optical disk.

  According to a sixth aspect of the present invention, there is provided the optical pickup adjusting mechanism according to the fifth aspect, wherein the waveform signal is a TE (Tracking Error) signal, and the coarse adjustment means adjusts the tilt amount to maximize the amplitude of the waveform signal. The fine adjustment means is configured to adjust to a tilt amount that maximizes the number of detected prepits.

  In the present invention, it is possible to detect the position where the S / N ratio is good and the error is not likely to occur by adjusting to the tilt amount with the maximum amplitude, and further fine adjustment based on the number of detected pre-pit signals. By performing the above, it is possible to adjust the tilt amount with high accuracy.

  An optical pickup adjusting mechanism according to a seventh aspect of the present invention provides a tilt amount between an optical disc in which prepits are provided in advance along a recording groove for recording data and an optical pickup that receives reflected light of light irradiated on the optical disc. In the optical pickup adjustment mechanism to be adjusted, determination means for determining whether or not reflected light that can be converted into a waveform signal has been received from an area for recording data on the optical disk, and reflection that can be converted into a waveform signal by the determination means When it is determined that light has been received, means for generating a waveform signal based on the received reflected light, means for performing coarse adjustment based on the amplitude of the generated waveform signal, and fine adjustment based on the error status of the waveform signal And a wave based on the reflected light received from the recording groove when the determining means determines that the reflected light that can be converted into a waveform signal is not received. Characterized in that it comprises means for generating a signal, means for performing coarse adjustment based on the amplitude of the generated waveform signal, means for detecting prepits, and means for performing fine adjustment based on the detection status of the prepits. .

  In the present invention, it is possible to adjust the tilt amount with high accuracy regardless of the data recording state of the optical disk.

  An optical disc apparatus according to an eighth aspect of the present invention is an optical pickup that receives reflected light of light irradiated on the optical disc, and the light according to any one of the third to seventh aspects of the invention that adjusts the tilt amount of the optical pickup. A pickup adjustment mechanism and means for reading data recorded on the optical disk based on the reflected light received by the optical pickup.

  In the present invention, it is possible to adjust the amount of tilt with high accuracy and suppress the amount of data reading errors.

  The tilt amount adjusting method, the optical pickup adjusting mechanism, and the optical disc apparatus of the present invention determine whether or not reflected light that can be converted into a waveform signal such as an RF signal has been received from an area where data of the optical disc is recorded, When it is determined that reflected light that can be converted into a waveform signal has been received, a waveform signal is generated based on the received reflected light, and coarse adjustment is performed based on the amplitude of the generated waveform signal. Make fine adjustments based on signal error conditions. In addition, when it is determined that the reflected light that can be converted into a waveform signal is not received, a waveform signal such as a TE signal is generated based on the reflected light received from the recording groove, and a rough signal is generated based on the amplitude of the generated waveform signal. After adjustment and coarse adjustment, fine adjustment is performed based on the pre-pit detection status.

  With this configuration, it is possible to adjust the tilt amount with high accuracy on an optical disc on which data is recorded based on an RF signal based on the recorded data. In particular, by adjusting the tilt amount that maximizes the amplitude of the RF signal, it is possible to detect a position where the S / N ratio is good and an error is unlikely to occur, and the number of errors in a very small range including the detected position. By detecting the tilt amount at the position where the error is minimized, the tilt amount can be adjusted with high accuracy even when the position determined based on the amplitude of the waveform signal is not the position where the signal error is minimized. It has an excellent effect. In addition, an excellent effect is obtained, for example, it is possible to prevent erroneous adjustment of the tilt amount due to the amplitude due to scratches or dirt on the optical disk.

  Even when no data is recorded on the optical disk, it is possible to detect a position where the S / N ratio is good and an error is not likely to occur by adjusting the tilt amount so that the amplitude of the TE signal is maximized. In addition, by performing fine adjustment based on the number of detected pre-pit signals, it is possible to adjust the tilt amount with high accuracy and the like.

  Hereinafter, the present invention will be described in detail with reference to the drawings illustrating embodiments thereof. FIG. 1 is a block diagram showing a configuration example of an optical disc apparatus according to the present invention. In FIG. 1, reference numeral 1 denotes an optical disk device such as a DVD recorder or a personal computer. The optical disk device 1 includes a control unit 10 such as a CPU that controls the entire device, and programs and data executed under the control of the control unit 10. A recording unit 11 such as a ROM that records various types of information and a storage unit 12 such as a RAM that temporarily stores data generated when a program is executed under the control of the control unit 10 are provided.

  The optical disk device 1 also includes a recording / reading unit 13 such as a disk drive for accessing and recording data on an optical disk 2 such as a CD and a DVD. The optical pickup 130 for receiving the reflected light of the irradiated light, the optical pickup adjusting mechanism 131 such as a tilt servo for adjusting the tilt amount of the optical pickup 130, the reading of data based on the reflected light and the optical disc 2 And a recording / reading mechanism 132 for outputting a signal for recording data.

  Further, the optical disk apparatus 1 outputs data to a push button that accepts an operator's operation, an input unit 14 such as a remote control operation light receiving circuit, a display device such as a monitor (not shown), and other external devices (not shown). Output unit 15.

  FIG. 2 is a block diagram schematically showing a configuration example of the recording / reading unit 13 of the optical disc apparatus 1 of the present invention. The optical pickup 130 provided in the recording / reading unit 13 includes a semiconductor laser 1300 serving as a light source, and a light beam emitted from the semiconductor laser 1300 is converted into parallel light by a collimator lens 1301 and transmitted through a beam splitter 1302 to be objective. The light is condensed by the lens 1303 and irradiated onto the recording surface of the optical disc 2. The reflected light of the light applied to the optical disk 2 is converted into parallel light by the objective lens 1303, refracted by the beam splitter 1302, condensed by the condenser lens 1304, and incident on the photodetector 1305.

  The detection surface of the photodetector 1305 is divided into four detection surfaces A to D by two orthogonal line segments with the optical axis of the incident reflected light as an intersection, and each of the four detection surfaces A divided into four. A light receiving element is disposed in each of .about.D. The light incident on the four detection surfaces A to D is photoelectrically converted by the light receiving element and output to the optical pickup adjusting mechanism 131 and the recording / reading mechanism 132.

  The optical pickup adjustment mechanism 131 includes a waveform signal generation circuit 1310 that generates a waveform signal based on an electrical signal obtained by photoelectrically converting reflected light, and a control circuit that calculates and controls the adjustment amount of the tilt amount based on the generated waveform signal. 1311 and a tilt amount adjustment circuit 1312 that adjusts the tilt amount based on a control signal output from the control circuit 1311. The optical pickup adjusting mechanism 131 outputs a control signal to the tilt amount adjusting circuit 1312 to adjust the tilt amount, thereby adjusting the relative angle between the optical disc 2 and the optical pickup 130 and irradiating the optical disc 2 with light. Adjust the beam angle.

  The waveform signal generation circuit 1310 includes an RF signal generation unit 1310a that generates an RF (Radio Frequency) signal, a TE signal generation unit 1310b that generates a TE (Tracking Error) signal, and an LPP signal that generates an LPP (Land Pre-Pit) signal. Generation means 1310c is provided. The RF signal, the TE signal, and the LPP signal generated by the waveform signal generation circuit 1310 are all generated based on the reflected light of the light beam applied to the optical disc 2, but the reflection position on the optical disc 2 and The calculation method for signal generation is different.

  Here, the recording surface of the optical disc 2 will be described. FIG. 3 is an explanatory diagram schematically showing the structure of the recording surface of the optical disc 2 that can be read by the optical disc apparatus 1 of the present invention. FIG. 3 schematically shows an enlarged perspective view of the optical disc 2 and a part of the recording surface of the optical disc 2. A recording groove 20 called a groove for recording data is spirally formed on the recording surface of the optical disc 2, and a land that is a convex portion along the recording groove 20 is formed between adjacent recording grooves 20. 21 is provided.

  The recording groove 20 is a data recording area in the optical disc 2, and data can be recorded by providing data pits 20a, 20a,. On the land 21, land pre-pits (LPP) 21a, 21a,... Are provided in advance according to a predetermined rule.

  The RF signal refers to the recording groove 20 including the data pits 20a, 20a,... When data is recorded in the recording area, that is, when the data pits 20a, 20a,. It is a signal generated based on reflected light. Note that, in the optical disc 2 on which no data is recorded, an RF signal cannot be generated by reflected light from a region other than a part of the prewritten region. In other words, when the tilt amount is adjusted with the RF signal, the adjustment is performed with the signal itself related to the recorded data, so that the adjustment with high accuracy is possible.

  The TE signal is a signal for detecting a tracking error, and is a signal generated based on reflected light from a region such as the recording groove 20 with respect to a light beam crossing the recording groove 20. Note that the TE signal can be generated from the reflected light of the recording groove 20 regardless of whether data is recorded on the optical disc 2 or not. That is, when adjusting the tilt amount with the TE signal, the accuracy as high as the RF signal cannot be obtained, but it is also possible to adjust based on the reflected light of the recording groove 20 where no data is recorded.

  The LPP signal is a signal based on reflected light from land pre-pits (LPP) 21a, 21a,.

  An example of a calculation method for generating each signal generated by the waveform signal generation circuit 1310 based on the reflected light reflected in each region illustrated in FIG. 3 will be described. FIG. 4 is a schematic diagram showing an example of an arithmetic circuit for various signals generated by the optical disc apparatus 1 of the present invention. FIG. 4A shows the RF signal generation means 1310 a of the waveform signal generation circuit 1310. As described above, the RF signal generation unit 1310a receives an input of an electric signal obtained by photoelectrically converting light received by the detection surfaces A to D obtained by dividing the photodetector 1305 into four. Here, the electric signal based on the light received by the detection surface A is signal A, the electric signal based on the light received by the detection surface B is signal B, the electric signal based on the light received by the detection surface C is signal C, and the detection surface An electric signal based on the light received by D is defined as a signal D. As is clear from FIG. 4A, the RF signal is generated based on the arithmetic expression of the following expression 1 using the signals A to D.

  RF signal = (signal A + signal D) + (signal B + signal C) Equation 1

  FIG. 4B shows a TE signal generation unit 1310 b of the waveform signal generation circuit 1310. As is clear from FIG. 4B, the TE signal is generated based on an arithmetic expression of the following expression 2 using the signals A to D. The arithmetic expression shown as Expression 2 is an example of an arithmetic expression for generating a TE signal, and utilizes the fact that a phase difference appears between the sum of diagonal outputs (signal A + signal C) and (signal B + signal D). ing.

  TE signal = (signal A + signal C) − (signal B + signal D) Equation 2

  FIG. 4C shows the LPP signal generation means 1310 c of the waveform signal generation circuit 1310. As is clear from FIG. 4C, the LPP signal is generated based on the following equation 3 using the signals A to D.

  LPP signal = (signal A + signal D) − (signal B + signal C) Equation 3

  Expressions 1 to 3 are examples of arithmetic expressions for generating each signal, and can be set as appropriate according to the configurations of the optical pickup 130 and the optical pickup adjustment mechanism 131.

  Next, processing of the optical pickup adjustment mechanism 131 provided in the optical disc apparatus 1 of the present invention will be described. FIG. 5 is a flowchart showing the first adjustment process of the optical pickup adjustment mechanism 131 of the present invention. The optical pickup adjusting mechanism 131 provided in the optical disc apparatus 1 positions the optical pickup 130 (S101). The adjustment of the tilt amount is performed to correct the relative angle between the optical disc 2 and the optical pickup 130 caused by factors such as warpage of the optical disc 2. However, the optical disc 2 is not necessarily uniformly warped from the vicinity of the center in the radial direction to the edge. Therefore, in the radial direction of the optical disc 2, it is necessary to obtain tilt amounts to be adjusted at several points from the inside of the recording surface near the center to the outside near the edge. The positioning in step S101 indicates that the optical pickup 130 is moved to a position where the tilt amount is to be obtained.

  The optical pickup adjusting mechanism 131 provided in the optical disc apparatus 1 determines whether or not the reflected light that can be converted into the RF signal is received from the data recording area of the optical disc 2 (S102). In step S102, a light beam is irradiated onto the data recording area of the optical disc 2 after positioning. When data is recorded in the data recording area, that is, when data pits 20a, 20a,... Are provided in the recording groove 20, it is determined that reflected light that can be converted into an RF signal is received.

  If it is determined in step S102 that reflected light that can be converted into an RF signal has been received (S102: YES), the optical pickup adjustment mechanism 131 generates an RF signal based on the received reflected light in the RF signal generation unit 1310a. (S103) A rough adjustment is performed to obtain a tilt amount that maximizes the amplitude of the generated RF signal (S104).

  After the coarse adjustment, the optical pickup adjustment mechanism 131 finely adjusts the tilt amount within a preset minute range centered on the tilt amount obtained by the coarse adjustment to obtain the tilt amount that minimizes the number of errors in the RF signal. It performs (S105). Although the optimum tilt amount is usually obtained by the coarse adjustment in step S104, the tilt amount at which the RF signal amplitude is maximized is not necessarily an error-free tilt amount depending on the optical disc 2, the optical pickup 130, or a combination thereof. Is not limited. Therefore, by performing the fine adjustment in step S105, it is possible to adjust the optimum tilt amount with high accuracy.

  Then, the optical pickup adjusting mechanism 131 records the tilt amount with respect to the position of the positioned optical pickup 130 in a memory provided in the control circuit 1311 (S106).

  If it is determined in step S102 that reflected light that can be converted into an RF signal is not received (S102: NO), the optical pickup adjustment mechanism 131 generates a TE signal based on the reflected light received from the recording groove 20 as a TE signal. Generated by the means 1310b (S107), coarse adjustment is performed to obtain the tilt amount that maximizes the amplitude of the generated TE signal (S108).

  After the coarse adjustment, the optical pickup adjusting mechanism 131 swings the tilt amount within a preset minute range around the tilt amount obtained by the coarse adjustment, and generates an LPP signal based on the reflected light received from the land 21 as an LPP signal generating unit. The land prepits 21a, 21a,... Are detected on the basis of the generated LPP signal (S110), and the land prepits 21a, 21a,... Detected within a preset detection time are generated. Fine adjustment is performed to obtain the amount of tilt that maximizes the number of (S111). The optimum tilt amount is usually obtained by the coarse adjustment in step S108. However, depending on the optical disc 2, the optical pickup 130, or a combination thereof, the tilt amount that maximizes the amplitude of the TE signal is not necessarily an error-free tilt amount. Is not limited. Therefore, by performing fine adjustment in steps S109 to S111, it is possible to adjust the optimum tilt amount with high accuracy.

  Then, the optical pickup adjustment mechanism 131 proceeds to step S106, and records the tilt amount with respect to the position of the positioned optical pickup 130 in a memory included in the control circuit 1311 (S106).

  Then, the optical pickup adjustment mechanism 131 determines whether or not there is an unadjusted position (S112). If it is determined that there is an unadjusted position (S112: YES), the process returns to Step S101 and the optical pickup 130 is moved to the unadjusted position. To adjust the tilt amount.

  If it is determined in step S112 that there is no unadjusted position (S112: NO), the first adjustment process is terminated. As described above, the first adjustment process can adjust the tilt amount with high accuracy by adjusting the tilt amount in two stages of coarse adjustment and fine adjustment. In addition, it is possible to perform high-precision adjustment based on an RF signal having a large amplitude for a recording area where data is recorded, and also to adjust a recording area where data is not recorded. Is possible.

  FIG. 6 is a flowchart showing the second adjustment process of the optical pickup adjustment mechanism 131 of the present invention. The second adjustment process is a method of adjusting the tilt amount without using the RF signal in the first adjustment process. Since the RF signal is not used, the second adjustment process is effective for the optical disc 2 on which no data is recorded. The optical pickup adjusting mechanism 131 provided in the optical disc apparatus 1 positions the optical pickup 130 (S201).

  The optical pickup adjusting mechanism 131 generates a TE signal based on the reflected light received from the recording groove 20 by the TE signal generating unit 1310b (S202), and performs rough adjustment to obtain a tilt amount that maximizes the amplitude of the generated TE signal. Perform (S203).

  After the coarse adjustment, the optical pickup adjusting mechanism 131 swings the tilt amount within a preset minute range around the tilt amount obtained by the coarse adjustment, and generates an LPP signal based on the reflected light received from the land 21 as an LPP signal generating unit. The land prepits 21a, 21a,... Are detected based on the generated LPP signal (S205), and the land prepits 21a, 21a,... Detected within a preset detection time are detected. Fine adjustment is performed to obtain a tilt amount that maximizes the number of (S206).

  Then, the optical pickup adjusting mechanism 131 records the tilt amount with respect to the position of the positioned optical pickup 130 in a memory provided in the control circuit 1311 (S207).

  Then, the optical pickup adjustment mechanism 131 determines whether or not there is an unadjusted position (S208). If it is determined that there is an unadjusted position (S208: YES), the process returns to Step S201, and the optical pickup 130 is moved to the unadjusted position. To adjust the tilt amount.

  If it is determined in step S207 that there is no unadjusted position (S208: NO), the second adjustment process is terminated.

  Note that the optical pickup adjustment mechanism 131 may adjust the tilt amount in any of the first adjustment process and the second adjustment process described above, or may perform both processes. The adjustment process to be performed is selected according to factors such as the type of the optical disc 2, data recording, and data reading.

  Then, when reading data from the optical disc 2 or recording data on the optical disc 2, the optical pickup adjustment mechanism 131 performs positioning to move the optical pickup 130 to the position of the optical disc 2 to be read or recorded, and corresponds to the position. Then, the recorded tilt amount is read from the memory, and the optical pickup 130 is adjusted based on the read tilt amount.

  In the above-described embodiment, the form in which the tilt amount is adjusted by driving the optical pickup is shown. However, the present invention is not limited to this, and the present invention can be developed in various forms such as tilting the optical disk motor to adjust the tilt amount. It is possible.

It is a block diagram which shows the structural example of the optical disk apparatus of this invention. It is a block diagram which shows typically the structural example of the recording / reading part of the optical disk apparatus of this invention. It is explanatory drawing which shows typically the structure of the recording surface of the optical disk which can be read with the optical disk apparatus of this invention. It is a schematic diagram which shows the example of the arithmetic circuit of the various signals which the optical disk device of this invention produces | generates. It is a flowchart which shows the 1st adjustment process of the optical pick-up adjustment mechanism of this invention. It is a flowchart which shows the 2nd adjustment process of the optical pick-up adjustment mechanism of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Optical disk apparatus 13 Recording / reading part 130 Optical pick-up 1304 Photo detector 131 Optical pick-up adjustment mechanism 1310 Waveform signal generation circuit 1311 Control circuit 1312 Tilt amount adjustment circuit 132 Recording / reading mechanism 2 Optical disk

Claims (8)

In a tilt amount adjusting method for adjusting a tilt amount between an optical disc and an optical pickup that receives reflected light of light irradiated on the optical disc,
Generate a waveform signal based on the reflected light received from the area where the optical disk data is recorded,
Perform coarse adjustment based on the amplitude of the generated waveform signal,
A tilt adjustment method, wherein fine adjustment is performed based on an error state of a waveform signal. In a tilt amount adjusting method for adjusting a tilt amount between an optical disc in which prepits are provided in advance along a recording groove for recording data and an optical pickup that receives reflected light of light irradiated on the optical disc,
Generate a waveform signal based on the reflected light received from the recording groove,
Perform coarse adjustment based on the amplitude of the generated waveform signal,
Detect pre-pits
A method for adjusting a tilt amount, wherein fine adjustment is performed based on a detection state of a prepit. In an optical pickup adjustment mechanism for adjusting a tilt amount between an optical disc and an optical pickup that receives reflected light of light irradiated on the optical disc,
Means for generating a waveform signal based on reflected light received from an area where data of an optical disk is recorded;
Coarse adjustment means for performing coarse adjustment based on the amplitude of the generated waveform signal;
An optical pickup adjustment mechanism comprising: fine adjustment means for performing fine adjustment based on an error condition of the waveform signal. The waveform signal is an RF (Radio Frequency) signal,
The coarse adjustment means is configured to adjust the tilt amount so that the amplitude of the waveform signal is maximized,
4. The optical pickup adjustment mechanism according to claim 3, wherein the fine adjustment unit is configured to adjust to a tilt amount that minimizes the number of errors. In an optical pickup adjusting mechanism that adjusts a tilt amount between an optical disc in which pre-pits are provided in advance along a recording groove for recording data and an optical pickup that receives reflected light of light irradiated on the optical disc,
Means for generating a waveform signal based on the reflected light received from the recording groove;
Coarse adjustment means for performing coarse adjustment based on the amplitude of the generated waveform signal;
Means for detecting pre-pits;
An optical pickup adjustment mechanism comprising: fine adjustment means for performing fine adjustment based on a pre-pit detection state. The waveform signal is a TE (Tracking Error) signal,
The coarse adjustment means is configured to adjust the tilt amount so that the amplitude of the waveform signal is maximized,
6. The optical pickup adjustment mechanism according to claim 5, wherein the fine adjustment unit is configured to adjust the tilt amount so that the number of detected prepits is maximized. In an optical pickup adjusting mechanism that adjusts a tilt amount between an optical disc in which pre-pits are provided in advance along a recording groove for recording data and an optical pickup that receives reflected light of light irradiated on the optical disc,
A determination means for determining whether or not reflected light that can be converted into a waveform signal has been received from an area for recording data on an optical disc;
When it is determined that the determination means has received reflected light that can be converted into a waveform signal,
Means for generating a waveform signal based on the received reflected light;
Means for performing coarse adjustment based on the amplitude of the generated waveform signal;
Means for performing fine adjustment based on the error condition of the waveform signal,
Furthermore, when the determination means determines that the reflected light that can be converted into a waveform signal is not received,
Means for generating a waveform signal based on the reflected light received from the recording groove;
Means for performing coarse adjustment based on the amplitude of the generated waveform signal;
Means for detecting pre-pits;
An optical pickup adjusting mechanism comprising: means for performing fine adjustment based on a detection state of a prepit. An optical pickup that receives reflected light of the light applied to the optical disc;
The optical pickup adjustment mechanism according to any one of claims 3 to 7, which adjusts a tilt amount of the optical pickup;
An optical disc apparatus comprising: means for reading data recorded on the optical disc based on reflected light received by the optical pickup.

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