JP2004355727A - Method and device for recording optical information - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method and device for recording optical information for accurately deciding an optimal strategy considering various setting parameters. <P>SOLUTION: The strategy of a strategy circuit 102 is changed, test recording is performed at least twice on an optical disk 10 by a different strategy, recording patterns by the test recording are reproduced, a shifting amount relative to various setting parameters of the strategy on the basis of a specific pattern among the reproduced patterns is independently detected by a recording shift detection part 112, a function for deciding an optimal strategy is derived from a relation between the detected shifting amount and the strategy used for the test recording by a calculation equation deriving part 113, and an optimal strategy is decided by a strategy deciding part 114 on the basis of the derived function. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an optical information recording method and apparatus having a strategy circuit for converting recording data into a desired recording pulse based on a predetermined write strategy, and in particular, to determine an optimal write strategy in consideration of various setting parameters. The present invention relates to an optical information recording method and apparatus.
[0002]
[Prior art]
Generally, when information is recorded on an optical information recording medium such as an optical disk, the recording data is modulated by an EFM (Eight to Fourteen Modulation) method, a recording pulse is formed based on the modulated signal, and the recording pulse is formed on the optical disk by the recording pulse. This is performed by controlling the intensity and the like of the irradiated laser beam and recording a mark called a pit on the recording layer of the optical disc.
[0003]
Here, a non-recording portion formed between the pits is called a land, and a recording pattern corresponding to the modulation signal is formed on the optical disk by the length of each pit and the length of each land. You.
[0004]
The pits are formed in the recording layer by using heat generated by the irradiation of the laser beam. Therefore, the recording pulse is formed in consideration of a heat storage effect at that time, thermal interference accompanying the formation of adjacent pits, and the like. Without this, it is not possible to form an accurate pit length and land length recording pattern.
[0005]
Therefore, the setting of various parameters for forming the recording pulse is called a write strategy (hereinafter simply referred to as a strategy), and the optical information recording apparatus is provided with a strategy circuit for executing the strategy.
[0006]
The strategy executed by this strategy circuit depends not only on the individual difference of the optical information recording apparatus, such as spot diameter variation of the pickup, variation in the mechanism accuracy, etc., but also depends on the manufacturer type and recording speed of the optical disc used for recording and reproduction. Here, if the optimal strategy is not set, the jitter at the time of reproduction increases, and accurate reproduction cannot be performed.
[0007]
To cope with this, an optimal strategy for an optical disc corresponding to each manufacturer type is determined, and this is stored in a memory in advance corresponding to each manufacturer type, and when recording information on the optical disc, the optical disc recorded on the optical disc is used. A method has also been proposed in which a manufacturer type is read, and an optimal strategy corresponding to the read manufacturer type is read from the memory and set in a strategy circuit.
[0008]
However, according to the above method, optimal recording can be performed on an optical disk of a manufacturer type stored in a memory in advance, but optimal recording can be performed on an optical disk of a manufacturer type not stored in a memory. In addition, optimal recording cannot be performed in this case if the recording speed is different even if the optical disk is of a manufacturer type stored in the memory in advance.
[0009]
Therefore, as shown in Patent Documents 1 and 2, a method has been proposed in which test recording is performed in advance for each recording condition, and an optimum strategy is determined based on the test recording so as to be compatible with various optical disks. I have.
[0010]
[Patent Document 1]
JP-A-5-144001
[Patent Document 2]
JP-A-4-137224
[Problems to be solved by the invention]
However, in the above-described conventional technique, it is not possible to determine which parameter needs to be adjusted and to what degree for a plurality of setting parameters of a strategy. For this reason, it is necessary to perform an optimal strategy setting corresponding to various parameters. Can not.
[0011]
In other words, as strategy setting parameters,
1) Front phase correction of recording pulse
2) Post-phase correction of recording pulse
3) Thermal interference correction
4) Recording mark length correction
The deviation amount is corrected by adjusting the recording power of the laser beam and the pulse width of the recording pulse, but these deviation amounts cannot be determined independently. The optimal strategy corresponding to the setting parameter cannot be determined.
[0012]
Therefore, an object of the present invention is to provide an optical recording information recording method and apparatus capable of accurately determining an optimal strategy in consideration of various setting parameters.
[0013]
[Means for Solving the Problems]
In order to achieve the above object, a first aspect of the present invention relates to an optical information recording method for recording information by converting recording data into recording pulses based on a predetermined write strategy. Irradiation is performed on a recording medium to perform recording, and a different recording pattern recorded by the different write strategy is reproduced, a new write strategy is determined according to a shift amount between the reproduced signals, and recording is performed according to the determination. It is characterized in that information is recorded by converting data into recording pulses.
[0014]
According to a second aspect of the present invention, there is provided an optical information recording apparatus having a strategy circuit for converting recording data into a recording pulse based on a predetermined write strategy, wherein various setting parameters of a write strategy of the strategy circuit are changed to change different write strategies. A test recording unit for performing at least two test recordings on the optical information recording medium by a strategy, a reproducing unit for reproducing a recording pattern recorded by the test recording unit, and a reproducing pattern reproduced by the reproducing unit. A deviation detecting means for independently detecting deviation amounts related to various setting parameters of the write strategy based on the specific pattern, and an optimum value based on a relationship between the deviation amount detected by the deviation detection unit and the write strategy used for the test recording. Strategy decision means for deciding write strategy Characterized by including the.
[0015]
According to a third aspect of the present invention, in the second aspect of the present invention, the shift detecting means includes a predetermined length of the fixed length land in a reproduction pattern in which a fixed length pit, a fixed length land, and a variable length pit follow. The phase shift amount of the front side of each pit is detected from the length shift of the pit.
[0016]
According to a fourth aspect of the present invention, in the second aspect of the present invention, the shift detecting means includes a variable length pit, a fixed length land, and a prescribed length of the fixed length land in a reproduction pattern following the fixed length pit. The amount of rear phase shift of each pit is detected from the length shift of the pit.
[0017]
According to a fifth aspect of the present invention, in the second aspect of the present invention, the displacement detecting means includes a predetermined length of the fixed length pit in a reproduction pattern in which a variable length land, a fixed length pit, and a fixed length land continue. The amount of pit shift due to thermal interference of each pit corresponding to each land is detected from the length shift from the pit.
[0018]
According to a sixth aspect of the present invention, in the second aspect of the present invention, the shift detecting means includes a fixed length land, a variable length pit, and a defined length of the variable length pit in a reproduction pattern following the fixed length land. It is characterized in that the length shift amount of each pit is detected from the length shift from the pit.
[0019]
According to a seventh aspect of the present invention, in the second aspect of the present invention, the strategy determining means determines an optimal write strategy based on a least square method from a shift amount in each test record detected by the shift detecting means. It is characterized by.
[0020]
According to an eighth aspect of the present invention, in the second aspect of the present invention, the strategy determination means sets the shift amount in the test recording by the first write strategy S1 detected by the shift detection means to D1, the second write strategy When the deviation amount in the test record by S2 is D2, simultaneous equations
D1 = a × S1 + b
D2 = a × S2 + b
A and b are calculated from the following, and a function using the calculated a and b
S = (D−b) / a
The optimum write strategy S is determined based on
[0021]
According to a ninth aspect of the present invention, in the second aspect of the present invention, the strategy determining means includes the function
S = (D−b) / a
And the optimum write strategy S is determined based on the correction table.
[0022]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of an optical information recording method and apparatus according to the present invention will be described in detail with reference to the accompanying drawings.
[0023]
FIG. 1 is a block diagram showing a main part of an optical information recording / reproducing apparatus configured by applying the optical information recording apparatus and method according to the present invention.
[0024]
In FIG. 1, the optical information recording / reproducing apparatus records / reproduces information on / from an optical disk 10 using a laser beam output from a laser oscillator 103.
[0025]
When information is recorded on the optical disk 10, a recording signal corresponding to desired recording information is encoded by the encoder 101 by the EFM method, and the encoded recording data is added to the strategy circuit 102.
[0026]
Here, various setting parameters of a predetermined strategy are set in the strategy circuit 102. The strategy circuit 102 corrects recording data to perform desired recording by using the various setting parameters of the strategy, A recording pulse for controlling the intensity of the output laser light is formed.
[0027]
The recording pulse formed by the strategy circuit 102 is added to the laser oscillator 103, and the laser oscillator 103 controls the output laser light in accordance with the recording pulse, and outputs the controlled laser light to the lens 104 and the half mirror. Irradiation is performed on the optical disk 10 rotating at a constant linear velocity or a constant rotation speed via a lens 105 and a lens 106, thereby recording a recording pattern including pits and lands corresponding to the recording data on the optical disk 10.
[0028]
When information recorded on the optical disk 10 is reproduced, a uniform reproduction laser beam is emitted from the laser oscillator 103 via the lens 104, the half mirror 105, and the lens 106 at a constant linear speed or a constant rotation speed. Irradiation.
[0029]
At this time, a reproducing laser beam having a lower intensity than the laser beam output from the laser oscillator 103 at the time of recording is used as the reproducing laser beam. The light is received by the light receiving unit 108 via the lens 107 and is converted into an electric signal.
[0030]
The electric signal output from the light receiving unit 108 corresponds to a recording pattern including pits and lands recorded on the optical disc 10. The electric signal output from the light receiving unit 108 is subjected to predetermined compensation processing in a reproduction compensation circuit 109, binarized in a binarization circuit 110, further decoded in a decoder 111, and output as a reproduction signal.
[0031]
Now, in the optical information recording / reproducing apparatus shown in FIG. 1, in order to set various parameters of the optimal strategy for the strategy circuit 102, various parameters of the strategy are changed for the optical disc 10 and predetermined parameters are set by different strategies. Is performed at least twice.
[0032]
Then, the test recording pattern is reproduced thereafter, and the recording deviation detection unit 112 measures the length deviation of a specific land or pit in the specific reproduction pattern output from the binarization circuit 110.
1) Phase shift amount of the front side of the pit with respect to the recording pulse
2) The amount of phase shift behind the pit with respect to the recording pulse
3) Amount of pit deviation from recording pulse due to thermal interference
4) Pit length deviation amount with respect to recording pulse
Are independently detected.
[0033]
Then, the arithmetic expression deriving unit 113 derives an arithmetic expression for determining an optimal strategy based on the deviation amount detected by the recording deviation detecting unit 112 and at least two strategies used in test recording.
[0034]
The strategy determining unit 114 uses an arithmetic expression for determining the optimal strategy derived by the arithmetic expression deriving unit 113 and uses the optical disk 10 used for test recording and the recording power of the laser beam and the recording pulse optimal for the recording conditions. A strategy for adjusting a pulse width or the like is determined and set in the strategy circuit 102.
[0035]
Next, the principle of detecting various shifts with respect to a recording pulse in the write shift detecting unit 112 shown in FIG. 1 will be described.
[0036]
FIG. 2 is a diagram showing an example of a recording pattern for detecting the amount of phase shift of the front side of a pit with respect to a recording pulse in the recording shift detecting unit 112.
[0037]
This recording pattern is a pattern in which pits PxT, lands LyT, and pits PzT are successively formed. As shown in f), it is changed to 3T, 4T,... 14T.
[0038]
Here, when the length of the fixed-length land LyT of the recording pattern is measured, the length of the fixed-length land LyT should be constant in an ideal recording state.
[0039]
However, if the length of the fixed-length land LyT deviates from the ideal prescribed length, the pit length of the pit PxT is fixed, so that the fixed-length land LyT has an ideal prescribed length. The shift amount corresponds to the front phase shift amount with respect to the recording pulse of each of the pits P3T, P4T,... P14T of 3T, 4T,.
[0040]
Therefore, test recording is performed using a recording pulse formed by using a certain strategy, and the reproduction pattern of the test recording based on the recording pulse is used by the recording displacement detection unit 112 to determine the length of the fixed length land LyT from the ideal length. If the shift amount is detected, it is possible to detect the front phase shift amount of the pits PzT for the recording pulse corresponding to this strategy, that is, the pits P3T, P4T,.
[0041]
FIG. 3 is a diagram illustrating an example of a front phase shift of a pit with respect to a recording pulse formed using a certain strategy.
[0042]
3A shows a recording pulse P formed by using a certain strategy, and FIGS. 3B and 3C show pits having a certain pit length with respect to the front edge PLE of the recording pulse P. FIG. 9 shows the front-side phase shift amount of PzT.
[0043]
Here, FIG. 3B and FIG. 3C show the case where the strategy is changed from S1 to S2, and the test recording is performed using the recording pulse P formed using the respective strategies S1 and S2. The phase shift amounts D1 and D2 of the front side of the pit PzT from the pulse P are shown.
[0044]
That is, FIG. 3B shows that, when test recording is performed using the recording pulse P formed by using the strategy S1, the recording shift detecting unit 112 moves the front side of the pit PzT from the front edge PLE of the recording pulse P to D1. FIG. 3C shows a case where test recording is performed using the recording pulse P formed using the strategy S2, and the recording shift detecting unit 112 detects the reproduction pit PzT. The front side shows a case where it is detected that the recording pulse P is shifted from the front side edge PLE by D2.
[0045]
FIG. 4 is a diagram illustrating an example of a recording pattern for detecting the amount of phase shift behind a pit with respect to a recording pulse in the recording shift detecting unit 112.
[0046]
This recording pattern is a pattern in which pits PxT, lands LyT, and pits PzT are consecutive. As shown in f), it is changed to 3T, 4T,... 14T.
[0047]
Here, when the length of the fixed-length land LyT of the recording pattern is measured, the length of the fixed-length land LyT should be constant in an ideal recording state.
[0048]
However, if the length of the fixed-length land LyT deviates from the ideal prescribed length, the pit length of the pit PzT is fixed. .. 14T in the strategy at the time of recording corresponds to the rear phase shift amount with respect to the recording pulse of each of the pits P3T, P4T,.
[0049]
Therefore, test recording is performed using a recording pulse formed by using a certain strategy, and the reproduction pattern of the test recording based on the recording pulse is used by the recording displacement detection unit 112 to determine the length of the fixed length land LyT from the ideal length. If the shift amount is detected, it is possible to detect the pit PxT for the recording pulse corresponding to this strategy, that is, the rear phase shift amount of the pits P3T, P4T,... P14.
[0050]
FIG. 5 is a diagram illustrating an example of a rear phase shift of a pit with respect to a recording pulse formed using a certain strategy.
[0051]
5A shows a recording pulse P formed using a certain strategy setting value, and FIGS. 5B and 5C show a certain pit with respect to the trailing edge PTE of the recording pulse P. The rear phase shift of the long pit PzT is shown.
[0052]
Here, FIG. 5B and FIG. 5C show the case where the strategy is changed from S1 to S2, and the test recording is performed using the recording pulse P formed using the respective strategies S1 and S2. The rear phase shift amounts D1 and D2 of the pit PxT from the pulse P are shown.
[0053]
That is, FIG. 5B shows that, when test recording is performed using the recording pulse P formed by using the strategy S1, the trailing edge PTE of the recording pulse P FIG. 5 (c) shows a case where a test recording is performed using a recording pulse P formed by using the strategy S2, and a recording pit is detected by the recording deviation detecting unit 112. The rear side of PxT shows a case where it is detected that the rear side is shifted by D2 from the front side edge PTE of the recording pulse P.
[0054]
FIG. 6 is a diagram illustrating an example of a recording pattern for detecting a pit deviation amount from a recording pulse due to thermal interference in the recording deviation detection unit 112.
[0055]
This recording pattern is a pattern in which a land LxT, a pit PyT, and a land LzT are continuous. The pit length of the pit PyT and the land length of the land LzT are fixed, and the land length of the land LxT is changed from FIG. 6A to FIG. As shown in f), it is changed to 3T, 4T,... 14T.
[0056]
Here, when the length of the fixed-length pit PyT of the recording pattern is measured, the length of the fixed-length pit PyT of the fixed length should be constant in an ideal recording state.
[0057]
However, if the length of the fixed-length pit PyT deviates from the ideal prescribed length, the land length of the land LzT is fixed. The shift amount is a front phase shift of the pits preceding the pits with the lands L3T, L4T,... L14T of the lands 3T, 4T,. Corresponds to the shift amount of the pit from the recording pulse.
[0058]
Therefore, test recording is performed with a recording pulse formed by using a certain strategy, and from the reproduction pattern of the test recording by this recording pulse, the recording shift detecting unit 112 determines the length of the fixed-length pit PyT from the ideal length. If the shift amount is detected, it is possible to detect the front-side shift amount due to thermal interference of the pit PyT with the recording pulse P corresponding to this strategy.
[0059]
FIG. 7 is a diagram illustrating an example of a front-side phase shift of a pit due to thermal interference with a recording pulse formed using a certain strategy.
[0060]
7A shows a recording pulse P formed by using a certain strategy, and FIGS. 7B and 7C show pits PyT due to thermal interference with the leading edge PLE of the recording pulse P. FIG. Of FIG.
[0061]
Here, FIG. 7B and FIG. 7C show the case where the strategy is changed from S1 to S2, and the test recording is performed using the recording pulse P formed using the respective strategies S1 and S2. The phase shift amounts D1 and D2 on the front side of the pit PyT from the pulse P are shown.
[0062]
That is, FIG. 7B shows that, when test recording is performed using the recording pulse P formed by using the strategy S1, the recording shift detecting unit 112 sets the front side of the pit PyT from the front edge PLE of the recording pulse P to D1. FIG. 7C shows a case where test recording is performed using a recording pulse P formed by using the strategy S2. The front side shows a case where it is detected that the recording pulse P is shifted from the front side edge PLE by D2.
[0063]
FIG. 8 is a diagram illustrating an example of a recording pattern for detecting a deviation amount of a pit length with respect to a recording pulse in the recording deviation detection unit 112.
[0064]
This recording pattern is a pattern in which a land LxT, a pit PyT, and a land LzT are continuous. The land length of the land LxT and the land length of the land LzT are fixed, and the pit length of the pit PyT is set as shown in FIGS. As shown in f), it is changed to 3T, 4T,... 14T.
[0065]
Here, when measuring the length of the variable-length pit PyT of the recording pattern, the length of the variable-length pit PyT should correspond to the ideal pit length in an ideal recording state.
[0066]
However, if the length of the variable-length pit PyT deviates from the ideal specified length, the land length of the land LxT and the land length of the land LzT are fixed. The amount of deviation from the length corresponds to the amount of deviation of the pits P3T, P4T,... P14T of 3T, 4T,.
[0067]
Therefore, test recording is performed using a recording pulse formed by using a certain strategy, and from the reproduction pattern of the test recording using this recording pulse, the recording shift detecting unit 112 determines the length of the variable-length pit PyT from the ideal length. If the shift amount is detected, the length shift amount of the pit PyT with respect to the recording pulse P corresponding to this strategy can be detected.
[0068]
FIG. 9 is a diagram showing an example of a pit length shift with respect to a recording pulse formed using a certain strategy.
[0069]
In FIG. 9, FIG. 9A shows a recording pulse P formed using a certain strategy, and FIGS. 9B and 9C show a shift in the length of the pit PyT with respect to the recording pulse P.
[0070]
Here, FIG. 9B and FIG. 9C show a case where the strategy is changed from S1 to S2, and the test recording is performed using the recording pulse P formed by using each of the strategies S1 and S2. The length shift of the pit PyT with respect to the pulse P is shown.
[0071]
That is, FIG. 9B shows that, when test recording is performed using the recording pulse P formed by using the strategy S1, the length of the pit PyT is set to D11 + D12 = FIG. 9C shows a case where it is detected that the pit PzT is shifted by D1. When the test recording is performed using the recording pulse P formed by using the strategy S2, the recording shift detecting unit 112 detects the pit PzT. The length indicates a case where it is detected that the recording pulse P is shifted by D21 + D22 = D2.
[0072]
Note that FIGS. 3, 5, 7, and 9 show a case where a multi-pulse including a main pulse and a plurality of sub-pulses following the main pulse is used as the recording pulse P.
[0073]
Also, the case where pits P3T, P4T,... P14T corresponding to 3T, 4T,.
[0074]
Incidentally, the deviation amounts D1 and D2 detected by the recording deviation detection unit 112 vary according to various setting parameters of the strategy, as described above. As a result of the analysis, it has been found that the deviation amounts D1 and D2 that fluctuate due to various setting parameters of this strategy change substantially linearly.
[0075]
That is, the amount of deviation in each test recording detected by the recording deviation detection unit 112 can be regarded as a linear change approximated based on the least squares method.
[0076]
Therefore, in the optical information recording / reproducing apparatus of this embodiment, for example, when two test recordings are performed, various setting parameters of the strategy and the deviation amounts D1 and D2 detected by the recording deviation detection unit 112 are detected. The optimal strategy can be determined by focusing on the linear relationship with
[0077]
FIG. 10 shows an example of the relationship between the strategy S used for test recording and the amount of deviation D detected from the reproduction pattern of the test recording by the recording deviation detection unit 112.
[0078]
The relationship between the strategy S used for the test recording and the amount of deviation D detected from the reproduction pattern of the test recording by the recording deviation detection unit 112 can be approximated by a substantially straight line PT as shown in FIG. .
[0079]
Accordingly, at least two points on this straight line, for example, a certain strategy S1 and the recording deviation detecting unit 112, the deviation amount D1 detected from the reproduction pattern of the test recording using this strategy S1 and the other strategy S2 and the recording deviation detecting unit 112. Then, if the shift amount D2 detected from the reproduction pattern of the test recording using the strategy S1 is obtained, the straight line PT can be specified. Strategy S can be determined.
[0080]
Specifically, the amount of deviation D detected by the recording deviation detection unit 112 when the strategy S is changed by several points is obtained, and the strategy S and the amount of deviation D are expressed by a general formula representing a straight line.
D = a × S + b
By solving the simultaneous equations, constants a and b are obtained, finally a strategy S corresponding to the ideal deviation amount D is obtained, and this strategy S is set in the strategy circuit 102 to obtain the recording pulse. Perform optimal correction.
[0081]
For example, suppose that the deviation detected from the reproduction pattern of the test recording using the strategy S1 as the recording deviation detection unit 112 is D1, and the deviation detected from the reproduction pattern of the test recording using the other strategy S2 is D2. ,
D1 = a × S1 + b
D2 = a × S2 + b
A and b are calculated from the following, and a function using the calculated a and b
S = (D−b) / a
The optimum strategy S is determined by substituting an output shift amount D for improving the recording quality, for example, for correcting an initial output shift or the like occurring in an equalizer or the like into this function.
[0082]
The function (straight line PT) for finding the optimal strategy S can be found for each of the pits P3T, P4T,... P14T of 3T, 4T,. Further, the function for obtaining the optimum strategy S can be obtained for each recording speed.
[0083]
FIG. 11 shows an example of a function for obtaining the optimal strategy S corresponding to each pit.
[0084]
In FIG. 11, P3T, P4T,..., P14T correspond to functions for finding the optimal strategy S corresponding to the pit lengths 3T, 4T,.
[0085]
In the above-described embodiment, when determining the optimal strategy when two test recordings are performed, the amount of deviation is detected in each test recording, the straight line PT is specified by the least square method, and the optimal strategy is determined. The details of the determination are described in detail. However, the present invention is not limited to this, and even if three or more test records are performed, the amount of deviation detected in each test record is calculated based on the least squares method. Thus, the straight line PT is specified, and the optimal strategy set value can be determined.
[0086]
FIG. 12 is a flowchart showing an example of the operation of the optical information recording / reproducing apparatus shown in FIG. 1 for setting an optimal strategy.
[0087]
In the optical information recording / reproducing apparatus shown in FIG. 1, in order to obtain an optimum strategy for recording information on an optical disc of a certain manufacturer at a predetermined recording speed, the optical disc is set in the optical information recording / reproducing apparatus. The test recording is performed at the predetermined recording speed.
[0088]
In this test recording, first, the first test recording is performed with the strategy of the initial value (step 201), and then the strategy is changed from the initial value, and the second test recording is performed with a strategy different from the initial value. (Step 202).
[0089]
Here, as an area used for test recording, for example, a PCA (Power Calibration Area) area may be used as long as the optical disk is a CD-R, a DVD-R, or the like. In the case of an optical disk of such a recording system, a part or all of the data recording area may be used.
[0090]
The test recording may be performed by sequentially changing the pit length or the land length as in the recording patterns shown in FIGS. 2, 4, 6, and 8, and FIGS. 2, 4, 6, and 6. 8 may be randomly recorded so as to include the recording pattern shown in FIG.
[0091]
Next, the recording pattern is reproduced (step 203), a specific reproduction pattern is extracted from the reproduced test recording, and the recording deviation amount in the specific reproduction pattern is determined by the recording deviation detecting unit 112 in FIG. , FIG. 5, FIG. 7, and FIG. 9 (step 204).
[0092]
Then, an approximate expression for obtaining an optimum strategy based on the recording deviation amount detected by the recording deviation detecting unit 112 is obtained (step 205).
[0093]
The process of obtaining the approximate expression for obtaining the optimal strategy is performed by the arithmetic expression deriving unit 113 shown in FIG. 1, and specifically, the process of obtaining the above-described function for obtaining the optimal strategy S.
[0094]
Next, an optimal strategy is determined using this approximate expression (step 206). The processing for determining the optimal strategy is performed by the strategy determining unit 114 shown in FIG. 1, and specifically, occurs in, for example, an equalizer or the like for improving the recording quality in the function for obtaining the optimal strategy S described above. This is a process of determining an optimal strategy S by substituting an output deviation amount D for correcting an initial output deviation or the like.
[0095]
Here, instead of the process of determining the optimum strategy S by substituting the output deviation amount D for improving the recording quality into the function for obtaining the optimum strategy S, a correction table obtained from the above function is prepared. The optimal strategy S may be determined based on this correction table.
[0096]
The optimal strategy S determined by the strategy determining unit 114 in this way is set in the strategy circuit 102 shown in FIG. 1, whereby the optimal strategy setting process ends.
[0097]
The above-described optimum strategy setting process may be performed each time the type of the optical disk is changed and each time the recording speed is changed. However, the optimum strategy determined in the above-described optimum strategy setting process is determined by the type of the optical disk and the recording speed. In the case where recording is performed again at the same recording speed on an optical disc of the same type, the optimal strategy stored in this memory is read out and set in the strategy circuit 102 when the recording is performed again. Is also good.
[0098]
【The invention's effect】
As described above, according to the present invention, the strategy of the strategy circuit is changed, test recording is performed at least twice on the optical information recording medium by a different strategy, and a recording pattern by the test recording is reproduced. Based on a specific pattern among the reproduced patterns, the amount of deviation of each set parameter of the strategy setting value is independently detected, and an optimal strategy is determined from the relationship between the detected amount of deviation and the strategy used for test recording. With this configuration, it is possible to easily determine and set the optimal strategy in consideration of various setting parameters.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a main part of an optical information recording / reproducing apparatus configured by applying an optical information recording method and apparatus according to the present invention.
FIG. 2 is a diagram showing an example of a recording pattern for detecting a front phase shift amount of a pit with respect to a recording pulse in a shift detector of the optical information recording / reproducing apparatus shown in FIG.
FIG. 3 is a diagram illustrating an example of a front phase shift of a pit with respect to a recording pulse formed using a certain strategy.
FIG. 4 is a diagram showing an example of a recording pattern for detecting a rear phase shift amount of a pit with respect to a recording pulse in a shift detector of the optical information recording / reproducing apparatus shown in FIG.
FIG. 5 is a diagram illustrating an example of a rear phase shift of a pit with respect to a recording pulse formed using a certain strategy.
6 is a diagram showing an example of a recording pattern for detecting a pit deviation amount from a recording pulse due to thermal interference in a deviation detecting unit of the optical information recording / reproducing apparatus shown in FIG.
FIG. 7 is a diagram illustrating an example of a front-side phase shift of a pit due to thermal interference with a recording pulse formed using a certain strategy.
8 is a diagram showing an example of a recording pattern for detecting a shift length of a pit with respect to a recording pulse in a shift detecting unit of the optical information recording / reproducing apparatus shown in FIG.
FIG. 9 is a diagram showing an example of a pit length shift with respect to a recording pulse formed using a certain strategy setting value.
10 is a graph showing an example of a relationship between a strategy S used for test recording and a shift amount D detected by a shift detecting unit of the optical information recording / reproducing apparatus shown in FIG. 1 from a reproduction pattern of the test recording. .
FIG. 11 is a graph showing an example of a function for finding an optimal strategy S corresponding to each pit.
FIG. 12 is a flowchart showing an example of the operation of the optical information recording / reproducing apparatus shown in FIG. 1 for setting an optimal strategy.
[Explanation of symbols]
10 Optical disk
101 Encoder
102 Strategy circuit
103 laser oscillator
104 lens
105 Half mirror
106 lenses
107 lenses
108 Receiver
109 Reproduction compensation circuit
110 binarization circuit
111 decoder
112 Recording deviation detecting unit
113 Operation expression derivation unit
114 Strategy decision unit

Claims (9)

In an optical information recording method of recording information by converting recording data into a recording pulse based on a predetermined write strategy,
Recording is performed by irradiating a recording pulse on the optical information recording medium using a different write strategy,
Playing different recording patterns recorded by the different write strategies,
A new write strategy is determined according to the amount of deviation between the reproduced signals,
An optical information recording method, comprising: converting recording data into a recording pulse in accordance with the determination; and recording information. In an optical information recording apparatus having a strategy circuit for converting recording data into a recording pulse based on a predetermined write strategy,
Test recording means for changing various setting parameters of a write strategy of the strategy circuit and performing test recording on the optical information recording medium at least twice by different write strategies,
Reproducing means for reproducing a recording pattern recorded by the test recording means,
A deviation detecting unit that independently detects deviation amounts related to various setting parameters of the write strategy based on a specific pattern among reproduction patterns reproduced by the reproduction unit;
An optical information recording apparatus, comprising: a strategy determining means for determining an optimum write strategy from a relationship between a shift amount detected by the shift detecting means and a write strategy used for the test recording. The deviation detecting means includes:
A method for detecting a front phase shift amount of each pit from a length shift of a length of the fixed length land from a specified length in a reproduction pattern including a fixed length pit, a fixed length land, and a variable length pit. Item 3. The optical information recording device according to Item 2. The deviation detecting means includes:
The method is characterized in that a rear phase shift amount of each pit is detected from a length shift from a specified length of the fixed length land in a reproduction pattern in which a variable length pit, a fixed length land, and a fixed length pit continue. The optical information recording device according to claim 2. The deviation detecting means includes:
Detects the amount of pit deviation due to thermal interference of each pit corresponding to each land from the deviation of the length of the fixed length pit from the specified length in the reproduction pattern that follows the variable length land, fixed length pit, and fixed length land 3. The optical information recording apparatus according to claim 2, wherein: The deviation detecting means includes:
A method of detecting a length shift amount of each pit from a length shift from a specified length of the length of the variable length pit in a reproduction pattern including a fixed length land, a variable length pit, and a fixed length land. Item 3. The optical information recording device according to Item 2. The strategy determination means,
3. The optical information recording apparatus according to claim 2, wherein an optimum write strategy is determined based on a least squares method from a deviation amount in each test recording detected by the deviation detection unit. The strategy determination means,
Assuming that the shift amount in the test recording by the first write strategy S1 detected by the shift detecting means is D1 and the shift amount in the test recording by the second write strategy S2 is D2, the simultaneous equations D1 = a × S1 + b
D2 = a × S2 + b
A and b are calculated from the above, and a function S = (D−b) / a using the calculated a and b
2. The optical information recording apparatus according to claim 1, wherein the optimum write strategy S is determined based on the following. The strategy determination means,
The function S = (D−b) / a
3. The optical information recording apparatus according to claim 2, further comprising a correction table obtained from the correction table, and determining an optimum write strategy S based on the correction table.

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