JP4072827B2 - Optical information recording method and apparatus - Google Patents

Description

[0001]
BACKGROUND 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. In particular, the optimum write strategy can be determined in consideration of various setting parameters. The present invention relates to an optical information recording method and apparatus.
[0002]
[Prior art]
In general, when recording information on an optical information recording medium such as an optical disk, the recording data is modulated by an EFM (Eight to Fourteen Modulation) system, a recording pulse is formed based on this modulation signal, and this recording pulse is used on the optical disk. This is done by recording marks called pits on the recording layer of the optical disc by controlling the intensity of the irradiated laser beam.
[0003]
Here, the 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 disc by the length of each pit and the length of each land. The
[0004]
By the way, the formation of pits in the recording layer is performed using heat generated by laser light irradiation. Therefore, the recording pulse is taken into account in consideration of the heat storage effect at that time, thermal interference accompanying the formation of adjacent pits, and the like. Otherwise, a recording pattern with accurate pit length and land length cannot be formed.
[0005]
Therefore, the setting of various parameters for forming the recording pulse is referred to as a write strategy (hereinafter simply referred to as a strategy), and the optical information recording apparatus is provided with a strategy circuit for executing this strategy.
[0006]
The strategy executed by this strategy circuit depends not only on individual differences of optical information recording devices such as pickup spot diameter variation and mechanism accuracy variation, but also on the manufacturer type and recording speed of the optical disk used for recording and reproduction. Here, if the optimum strategy is not set, jitter during reproduction increases and accurate reproduction cannot be performed.
[0007]
In order to cope with this, the optimum strategy of the optical disc corresponding to each manufacturer type is obtained, and this is stored in advance in a memory corresponding to each manufacturer type, and when recording information on the optical disc, the optical disc recorded on the optical disc is recorded. There has also been proposed a method of reading the manufacturer type, reading the optimum strategy corresponding to the read manufacturer type from the memory, and setting it in the strategy circuit.
[0008]
However, according to the above method, optimum recording can be performed on a manufacturer-type optical disc stored in the memory in advance, but optimum recording can be performed on a manufacturer-type optical disc not stored in the memory. Moreover, even in the case of a manufacturer-type optical disk stored in advance in the memory, if the recording speed is different, optimum recording cannot be performed in this case.
[0009]
Therefore, as shown in Patent Document 1 and Patent Document 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. Yes.
[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-mentioned conventional technology, it is impossible to determine which parameter needs to be adjusted to what degree with respect to a plurality of existing strategy setting parameters, and for this purpose, optimal strategy setting corresponding to various parameters is performed. I can't.
[0011]
In other words, as a strategy setting parameter,
1) Recording pulse front phase correction
2) Rear phase correction of recording pulse
3) Thermal interference correction
4) Correction of recording mark length
The amount of deviation is corrected by adjusting the recording power of the laser beam, the pulse width of the recording pulse, etc., but these amounts of deviation cannot be determined independently. The optimal strategy corresponding to the setting parameter cannot be determined.
[0012]
Accordingly, an object of the present invention is to provide an optical recording information recording method and apparatus capable of accurately determining an optimum strategy considering various setting parameters.
[0013]
[Means for Solving the Problems]
In order to achieve the above object, an invention according to claim 1 is an optical information recording method for recording information on an optical information recording medium by converting recording data into a recording pulse based on a write strategy, and a specific parameter of the write strategy. The test recording of the specific pattern capable of independently detecting the shift amount related to the parameter is performed on the optical information recording medium at least twice by the different write strategy in which the optical recording medium is changed. The recorded pattern recorded in the reproduction pattern is reproduced, the deviation amount related to the particular parameter of the write strategy is detected based on the specific pattern in the reproduced reproduction pattern, and the optimum write strategy is determined based on the detected deviation amount. in order to Straight line Obtain an approximate expression Straight line The optimum write strategy is determined based on the approximate expression.
[0014]
The invention of claim 2 In an optical information recording method for recording information on an optical information recording medium by converting recording data into a recording pulse based on a write strategy, the light is recorded by a different write strategy in which a parameter relating to a front phase shift of a recording pit of the write strategy is changed. Test recording of a plurality of specific patterns in which a fixed-length pit, a fixed-length land, and a variable-length pit with a changed pit length are continued on the information recording medium at least twice, and recorded on the optical information recording medium by the test recording. The recorded phase of the recorded pit is detected from a deviation from a predetermined length of the fixed-length land in the specific pattern in the reproduced pattern, and the detected front-side phase deviation is detected. Determine the optimal write strategy based on It is characterized by that.
[0015]
The invention of claim 3 In an optical information recording method for recording information on an optical information recording medium by converting recording data into a recording pulse based on a write strategy, the write strategy uses the different write strategy in which a parameter relating to a phase shift behind a recording pit of the write strategy is changed. Test recording of a plurality of specific patterns in which a variable-length pit, a fixed-length land, and a fixed-length pit with varying pit lengths are performed on the optical information recording medium at least twice, and recording on the optical information recording medium by the test recording The recorded recording pattern is reproduced, and the amount of the rear phase shift of the recording pit is detected from the deviation from the fixed length of the fixed length land in the specific pattern in the reproduced reproduction pattern, and the detected rear phase is detected. Determine the optimal write strategy based on the amount of deviation It is characterized by that.
[0016]
The invention of claim 4 In an optical information recording method for recording information on an optical information recording medium by converting recording data into a recording pulse based on a write strategy, the light is recorded by a different write strategy in which parameters relating to recording pit deviation due to thermal interference of the write strategy are changed. Test recording of a plurality of specific patterns in which a land having a variable length, a fixed length pit, and a fixed length land followed by changing the land length is performed at least twice on the information recording medium, and recorded on the optical information recording medium by the test recording. The recorded pattern is reproduced, the pit deviation amount due to thermal interference of the recorded pit is detected from the deviation from the fixed length pit in the specific pattern in the reproduced pattern, and the detected pit deviation amount is detected. Determine the optimal write strategy based on It is characterized by that.
[0017]
The invention of claim 5 In an optical information recording method for recording information on an optical information recording medium by converting recording data into a recording pulse based on a write strategy, the light is recorded by a different write strategy in which a parameter relating to a deviation in the length of a recording pit of the write strategy is changed. A test record of a plurality of specific patterns in which a fixed-length land, a variable-length pit having a changed pit length, and a fixed-length land are followed on the information recording medium is performed at least twice, and recorded on the optical information recording medium by the test recording. The recorded pattern is reproduced, and the recorded pit length deviation amount is detected from a deviation from the specified length of the variable length pit in the specific pattern in the reproduced reproduction pattern, and the detected deviation amount is Determine the optimal write strategy based on It is characterized by that.
[0018]
According to a sixth aspect of the present invention, there is provided an optical information recording apparatus having a strategy circuit for converting recording data into recording pulses based on the write strategy according to the first aspect of the invention, wherein different write parameters are obtained by changing specific parameters of the write strategy. A test recording unit for performing test recording of a specific pattern at least twice on the optical information recording medium by a strategy, the amount of deviation relating to the parameter being independently detectable, and the test recording unit on the optical information recording medium Reproducing means for reproducing the recording pattern recorded on the recording medium; deviation detecting means for detecting a deviation amount related to the specific parameter of the write strategy based on the specific pattern among the reproduction patterns reproduced by the reproducing means; Based on the amount of deviation detected by the deviation detection means, For determining the Tej Straight line An arithmetic expression deriving means for obtaining an approximate expression, and the arithmetic expression deriving means Straight line Write strategy determining means for determining an optimum write strategy based on an approximate expression, and setting means for setting the optimum write strategy determined by the write strategy determining means in the strategy circuit.
[0019]
The invention of claim 7 is a 6 In the invention of The specific pattern is a plurality of patterns followed by a fixed-length pit, a fixed-length land, and a variable-length pit whose pit length is changed, and the deviation detecting means is a deviation from a predetermined length of the fixed-length land in the specific pattern. To detect the amount of front phase shift corresponding to the variable length pit It is characterized by that.
[0020]
Further, the invention of claim 8 is a claim. 6 In the invention of The specific pattern is a plurality of patterns followed by a variable length pit with a changed pit length, a fixed length land, and a fixed length pit, and the shift detection means detects a shift from a specified length of the fixed length land in the specific pattern. To detect the rear phase shift amount corresponding to the variable length pit. It is characterized by that.
[0021]
Further, in the invention of claim 9, the deviation detecting means corresponds to the variable length land from a deviation from a specified length of the fixed length pit of a specific pattern in which a variable length land, a fixed length pit, and a fixed length land follow. It is characterized by detecting a pit shift amount due to thermal interference of fixed-length pits.
The invention according to claim 10 is the invention according to claim 6, wherein the deviation detecting means is configured to detect the deviation from a prescribed length of the variable length pit of a specific pattern in which a fixed length land, a variable length pit, and a fixed length land follow. It is characterized by detecting the length shift amount of the variable length pit.
The invention according to claim 11 is the approximate expression for determining the optimum write strategy based on the least square method from the deviation amount detected by the deviation detecting means in the invention according to claim 6. It is characterized by calculating | requiring.
According to a twelfth aspect of the present invention, in the invention of the sixth aspect, the arithmetic expression deriving means determines the amount of deviation in the test recording by the first write strategy S1 detected by the deviation detecting means as D1 and the second write. When the amount of deviation in the test record by the strategy S2 is D2, simultaneous equations
D1 = a × S1 + b
D2 = a × S2 + b
And a function using the calculated a and b and the output deviation amount D for correcting the initial output deviation
S = (D−b) / a
Seeking
The write strategy determining means determines the optimum write strategy based on the function.
The invention according to claim 13 is the invention according to claim 12, wherein the strategy determining means is the function.
S = (D−b) / a
And the optimum write strategy is determined based on the correction table.
[0022]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of an optical information recording method and apparatus according to the present invention will be described below 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 constructed by applying the optical information recording apparatus and method according to the present invention.
[0024]
In FIG. 1, this optical information recording / reproducing apparatus records / reproduces information on / from an optical disc 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 for a predetermined strategy are set in the strategy circuit 102, and the strategy circuit 102 corrects the recording data to perform desired recording by using the various setting parameters for the strategy, and from the laser oscillator 103. A recording pulse for controlling the intensity of the output laser beam is formed.
[0027]
The recording pulse formed by the strategy circuit 102 is applied to the laser oscillator 103. The laser oscillator 103 controls the output laser beam in response to the recording pulse, and the controlled laser beam is transmitted to the lens 104, the half mirror. The optical disk 10 rotating at a constant linear speed or a constant rotational speed is irradiated through the lens 105 and the lens 106, whereby a recording pattern composed of pits and lands corresponding to the recording data is recorded on the optical disk 10.
[0028]
When reproducing the information recorded on the optical disc 10, the optical disc 10 is rotated with a uniform reproduction laser beam from the laser oscillator 103 through the lens 104, the half mirror 105, and the lens 106 at a constant linear speed or a constant rotation speed. Irradiate.
[0029]
As the reproduction laser light at this time, the reproduction laser light having a lower intensity than the laser light output from the laser oscillator 103 at the time of recording is used, and the reflected light from the optical disk 10 by the reproduction laser light includes the lens 106 and the half mirror 105. The light is received by the light receiving unit 108 through the lens 107 and converted into an electric signal.
[0030]
The electrical signal output from the light receiving unit 108 corresponds to a recording pattern composed of pits and lands recorded on the optical disc 10. The electrical signal output from the light receiving unit 108 is subjected to predetermined compensation processing by the reproduction compensation circuit 109, binarized by the binarization circuit 110, further decoded by the decoder 111, and output as a reproduction signal.
[0031]
In the optical information recording / reproducing apparatus shown in FIG. 1, in order to set various parameters of the optimum strategy for the strategy circuit 102, the various parameters of the strategy are changed for the optical disc 10 according to different strategies. Test recording is performed to record the recording pattern of at least twice.
[0032]
The test recording pattern is then reproduced, and the recording deviation detection unit 112 measures the deviation in the length of a specific land or pit in the specific reproduction pattern output from the binarization circuit 110.
1) A pit front phase shift amount with respect to a recording pulse
2) Rear phase shift amount of pit with respect to recording pulse
3) Pit deviation from recording pulse due to thermal interference
4) Pit length deviation with respect to recording pulse
Are detected independently.
[0033]
An arithmetic expression deriving unit 113 derives an arithmetic expression for determining an optimum strategy based on the deviation amount detected by the recording deviation detection unit 112 and at least two strategies used in the test recording.
[0034]
The strategy determination unit 114 uses the calculation formula for determining the optimum strategy derived by the calculation formula deriving unit 113 to use the optical disc 10 used for test recording and the laser beam recording power and recording pulse optimal for the recording conditions. A strategy for adjusting the pulse width and the like is determined and set in the strategy circuit 102.
[0035]
Next, the principle of detection of various deviations with respect to the recording pulse in the recording deviation detection unit 112 shown in FIG. 1 will be described.
[0036]
FIG. 2 is a diagram illustrating an example of a recording pattern for the recording deviation detection unit 112 to detect the pit front side phase deviation amount with respect to the recording pulse.
[0037]
This recording pattern is a pattern in which pits PxT, lands LyT, and pits PzT are continuous. The pit lengths of the pits PxT and lands LyT are fixed, and the pit lengths of the pits PzT are shown in FIG. 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 specified length, the pit length of the pit PxT is fixed. The shift amount corresponds to the front phase shift amount with respect to the recording pulse of each pit P3T, P4T,... P14T of 3T, 4T,.
[0040]
Therefore, test recording is performed with a recording pulse formed using a certain strategy, and the recording deviation detection unit 112 determines from the ideal length of the fixed-length land LyT from the reproduction pattern of the test recording by this recording pulse. If the shift amount is detected, it is possible to detect the front phase shift amount of the pits PzT, that is, the pits P3T, P4T,... P14T with respect to the recording pulse corresponding to this strategy.
[0041]
FIG. 3 is a diagram showing an example of a pit front side phase shift with respect to a recording pulse formed using a certain strategy.
[0042]
3A shows a recording pulse P formed 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. The amount of front side phase shift of PzT is shown.
[0043]
Here, FIG. 3B and FIG. 3C show recording when the strategy is changed from S1 to S2 and test recording is performed using the recording pulse P formed using the respective strategies S1 and S2. The front side phase shift amounts D1 and D2 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 using the strategy S1, the front side of the pit PzT is set to D1 from the front edge PLE of the recording pulse P by the recording deviation detection unit 112. FIG. 3C shows the case where the recording deviation P is detected by the recording deviation detector 112 when test recording is performed using the recording pulse P formed using the strategy S2. The front side shows a case where it is detected that the recording pulse P is deviated by D2 from the front edge PLE of the recording pulse P.
[0045]
FIG. 4 is a diagram showing an example of a recording pattern for detecting the rear phase shift amount of the pit with respect to the recording pulse in the recording deviation detecting unit 112.
[0046]
This recording pattern is a pattern in which pits PxT, lands LyT, and pits PzT are continuous. The land length of lands LyT and the pit length of pits PzT are fixed, and the pit lengths of pits PxT are shown in FIGS. 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 specified length, the pit length of the pit PzT is fixed, and therefore, from the ideal specified length of the fixed-length land LyT length. The amount of deviation corresponds to the amount of rear phase deviation with respect to the recording pulse of each pit P3T, P4T,... P14T of 3T, 4T,.
[0049]
Therefore, test recording is performed with a recording pulse formed using a certain strategy, and the recording deviation detection unit 112 determines from the ideal length of the fixed-length land LyT from the reproduction pattern of the test recording by this recording pulse. If the shift amount is detected, the pit PxT for the recording pulse corresponding to this strategy, that is, the rear phase shift amount of the pits P3T, P4T,... P14 can be detected.
[0050]
FIG. 5 is a diagram showing 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. FIG. The rear phase shift of the long pit PzT is shown.
[0052]
Here, FIG. 5B and FIG. 5C show recording when the strategy is changed from S1 to S2 and 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. 5 (b) shows that when test recording is performed using the recording pulse P formed using the strategy S1, the rear side edge PTE of the recording pulse P is located behind the pit PxT in the recording deviation detection unit 112. FIG. 5C shows a case where a recording pit is detected by the recording deviation detection unit 112 when test recording is performed using the recording pulse P formed using the strategy S2. The rear side of PxT indicates a case where it is detected that the recording pulse P is shifted from the front side edge PTE by D2.
[0054]
FIG. 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 the recording deviation detection unit 112.
[0055]
This recording pattern is a pattern in which lands LxT, pits PyT, and lands 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 shown in FIGS. 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 should be constant in an ideal recording state.
[0057]
However, if the length of the fixed-length pit PyT deviates from the ideal specified length, the land length of the land LzT is fixed. Therefore, the ideal specified length of the fixed-length land LyT length The shift amount is the front phase shift with respect to the recording pulse of the pit preceded by each land L3T, L4T,... L14T of the 3T, 4T,. This corresponds to the amount of pit deviation from the recording pulse.
[0058]
Therefore, test recording is performed with a recording pulse formed using a certain strategy, and the recording deviation detection unit 112 determines from the ideal length of the fixed-length pit PyT from the reproduction pattern of the test recording by this recording pulse. If the shift amount is detected, the front phase shift amount due to the thermal interference of the pit PyT with respect to the recording pulse P corresponding to this strategy can be detected.
[0059]
FIG. 7 is a diagram showing an example of a pit front phase shift due to thermal interference with a recording pulse formed using a certain strategy.
[0060]
7A shows a recording pulse P formed using a certain strategy. FIGS. 7B and 7C show pits PyT due to thermal interference with the front edge PLE of the recording pulse P. FIG. The front side phase shift is shown.
[0061]
Here, FIG. 7B and FIG. 7C show recording when the strategy is changed from S1 to S2 and test recording is performed using the recording pulse P formed using the respective strategies S1 and S2. The front side phase shift amounts D1 and D2 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 using the strategy S1, the front side of the pit PyT is D1 from the front edge PLE of the recording pulse P in the recording deviation detection unit 112. FIG. 7C shows a case where the recording deviation detection unit 112 detects the reproduction pit PzT when test recording is performed using the recording pulse P formed using the strategy S2. The front side shows a case where it is detected that the recording pulse P is deviated by D2 from the front edge PLE of the recording pulse P.
[0063]
FIG. 8 is a diagram showing an example of a recording pattern for the recording deviation detection unit 112 to detect the pit length deviation amount with respect to the recording pulse.
[0064]
This recording pattern is a pattern in which lands LxT, pits PyT, and lands 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 shown in FIGS. As shown in f), it is changed to 3T, 4T,... 14T.
[0065]
Here, when the length of the variable-length pit PyT of the recording pattern is measured, 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 from the recording pulse of each pit P3T, P4T,... P14T of 3T, 4T,.
[0067]
Therefore, test recording is performed with a recording pulse formed using a certain strategy, and the recording deviation detection unit 112 determines from the ideal length of the variable-length pit PyT from the reproduction pattern of the test recording by this recording pulse. If the deviation amount is detected, the length deviation 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]
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. FIG.
[0070]
Here, FIG. 9B and FIG. 9C show recording when the strategy is changed from S1 to S2 and test recording is performed using the recording pulse P formed using the respective strategies S1 and S2. The length deviation of the pit PyT with respect to the pulse P is shown.
[0071]
That is, FIG. 9B shows that when the test recording is performed using the recording pulse P formed using the strategy S1, the length of the pit PyT in the recording deviation detection unit 112 is D11 + D12 = FIG. 9C shows a case where it is detected that there is a deviation by D1, and FIG. 9C shows a case where the recording deviation detection unit 112 detects the pit PzT when test recording is performed using the recording pulse P formed using the strategy S2. The length shows a case where it is detected that the recording pulse P is deviated by D21 + D22 = D2.
[0072]
3, 5, 7, and 9, the recording pulse P is shown as a multi-pulse including a main pulse and a plurality of sub-pulses following the main pulse.
[0073]
Further, as recording pulses, pits P3T, P4T,... P14T corresponding to 3T, 4T,.
[0074]
By the way, as described above, the shift amounts D1 and D2 detected by the recording shift detector 112 vary depending on various setting parameters of the strategy. As a result of analysis, it has been clarified that the shift amounts D1 and D2 that vary depending on various setting parameters of the strategy change in a substantially linear shape.
[0075]
That is, the deviation amount in each test recording detected by the recording deviation detection unit 112 can be regarded as a linear change approximated based on the least square method.
[0076]
Therefore, in the optical information recording / reproducing apparatus of this embodiment, for example, when the test recording is performed twice, the various setting parameters of the strategy and the detected deviation amounts D1 and D2 detected by the recording deviation detection unit 112 are used. It is possible to determine the optimal strategy by paying attention to 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 this 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 detector 112 can be approximated by a straight line PT as shown in FIG. .
[0079]
Therefore, at least two points on the straight line, for example, a certain strategy S1 and the recording deviation detection unit 112, the deviation amount D1 detected from the reproduction pattern of the test recording using this strategy S1, and another strategy S2 and the recording deviation detection unit 112. If the deviation amount D2 detected from the reproduction pattern of the test recording using the strategy S1 is obtained, the straight line PT can be specified, and the straight line PT is used, for example, to optimize the deviation amount D to zero. Strategy S can be determined.
[0080]
Specifically, the deviation amount D detected by the recording deviation detection unit 112 when the strategy S is changed by several points is obtained, and at this time, the strategy S and the deviation amount D are general expressions representing straight lines.
D = a × S + b
The constants a and b are obtained by solving the simultaneous equations and finally the strategy S corresponding to the ideal deviation amount D is obtained. By setting this strategy S in the strategy circuit 102, the recording pulse Perform optimal correction.
[0081]
For example, suppose that the amount of deviation detected from the reproduction pattern of the test recording using the strategy S1, which is the recording deviation detection unit 112, is D1, and the amount of 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 function and a function using the calculated a and b is calculated.
S = (D−b) / a
The optimum strategy S is determined by substituting an output deviation amount D for improving the recording quality, for example, for correcting an initial output deviation or the like occurring in an equalizer or the like, into this function.
[0082]
The function (straight line PT) for obtaining the optimum strategy S can be obtained corresponding to each of the pits P3T, P4T,... P14T of 3T, 4T,. The functions for obtaining the optimum strategy S can also be obtained corresponding to the recording speed.
[0083]
FIG. 11 shows an example of a function for obtaining the optimum strategy S corresponding to each pit.
[0084]
In FIG. 11, P3T, P4T,... P14T correspond to functions for obtaining the optimum strategy S corresponding to the pit lengths 3T, 4T,.
[0085]
In the above-described embodiment, when determining the optimum strategy when the test recording is performed twice, the respective shift amounts are detected in each test recording, and the straight line PT is specified by the least square method to determine the optimum strategy. However, the present invention is not limited to this. Even when three or more test recordings are performed, the least square method is used to calculate the amount of deviation detected in each test recording. Thus, the straight line PT can be specified and the optimum strategy setting 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 the optimum strategy.
[0087]
In the optical information recording / reproducing apparatus shown in FIG. 1, in order to obtain an optimum strategy when information is recorded on a certain manufacturer's optical disk at a predetermined recording speed, the optical disk is set in the optical information recording / reproducing apparatus. Then, 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 in the case of an optical disc such as a CD-R and a DVD-R. For example, a Z-CLV system may be used. In the case of an optical disc of such a recording method, 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 land length as in the recording patterns shown in FIGS. 2, 4, 6, and 8, and FIG. 2, FIG. 4, FIG. Random recording may be performed so that the recording pattern shown in FIG.
[0091]
Next, the recording pattern is reproduced (step 203), a specific reproduction pattern in the reproduced test recording is extracted, and the recording deviation amount in the specific reproduction pattern is detected by the recording deviation detection unit 112 in FIG. 5, FIG. 7, and FIG. 9 (step 204).
[0092]
Then, an approximate expression for obtaining the optimum strategy is obtained based on the recording deviation amount detected by the recording deviation detection unit 112 (step 205).
[0093]
The process for obtaining the approximate expression for obtaining the optimum strategy is performed by the arithmetic expression deriving unit 113 shown in FIG. 1, and specifically, the process for obtaining the function for obtaining the optimum strategy S described above.
[0094]
Next, an optimum strategy is determined using this approximate expression (step 206). The process for determining the optimum strategy is performed by the strategy decision unit 114 shown in FIG. 1, and specifically occurs in, for example, an equalizer or the like for improving the recording quality to the above-described function for obtaining the optimum strategy S. In this process, an optimum strategy S is determined by substituting an output deviation amount D for correcting an initial output deviation or the like.
[0095]
Here, in place of the process of determining the optimum strategy S by substituting the output shift 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 optimum 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, thereby completing the optimal strategy setting process.
[0097]
The optimum strategy setting process may be performed every time the type of the optical disk is changed and every time the recording speed is changed. However, the optimum strategy determined in the optimum strategy setting process is determined based on the type of the optical disk and the recording speed. If the same type of optical disk is recorded again with the same recording speed, the optimum strategy stored in this memory is read out and set in the strategy circuit 102. Also good.
[0098]
【The invention's effect】
As described above, according to the present invention, the strategy of the strategy circuit is changed and at least two test recordings are performed on the optical information recording medium using different strategies, and the recording pattern by the test recording is reproduced and the reproduced Independently detecting deviation amounts related to various setting parameters of the strategy setting value based on a specific pattern in the reproduced pattern, and determining the optimum strategy from the relationship between the detected deviation amount and the strategy used for test recording Thus, the optimum strategy considering various setting parameters can be easily determined and set.
[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.
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 detection unit of the optical information recording / reproducing apparatus shown in FIG.
FIG. 3 is a diagram illustrating an example of a pit front side phase shift with respect to a recording pulse formed using a certain strategy.
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 detection unit of the optical information recording / reproducing apparatus shown in FIG.
FIG. 5 is a diagram showing 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 shift amount from a recording pulse due to thermal interference in a shift detection unit of the optical information recording / reproducing apparatus shown in FIG. 1. FIG.
FIG. 7 is a diagram showing an example of a pit front side phase shift 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 pit length deviation amount with respect to a recording pulse in a deviation detection unit of the optical information recording / reproducing apparatus shown in FIG. 1. 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 deviation amount D detected by a deviation detection 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 obtaining an optimum strategy S corresponding to each pit.
12 is a flowchart showing an example of the operation of the optical information recording / reproducing apparatus shown in FIG. 1 for setting an optimum strategy.
[Explanation of symbols]
10 Optical disc
101 Encoder
102 Strategy circuit
103 Laser oscillator
104 lenses
105 half mirror
106 lenses
107 lenses
108 Light receiver
109 Regenerative compensation circuit
110 Binary circuit
111 decoder
112 Recording deviation detection unit
113 Arithmetic expression deriving unit
114 Strategy decision unit

Claims (13)

In an optical information recording method for recording information on an optical information recording medium by converting recording data into recording pulses based on a write strategy,
Performing at least twice a test recording of a specific pattern capable of independently detecting a deviation amount related to the parameter on the optical information recording medium by a different write strategy in which the specific parameter of the write strategy is changed,
Reproducing the recording pattern recorded on the optical information recording medium by the test recording,
Detecting a deviation amount related to the specific parameter of the write strategy based on the specific pattern in the reproduced reproduction pattern;
Obtaining a linear approximation formula for determining the optimal write strategy based on the detected deviation amount,
The optical information recording method characterized by determining an optimum write strategy based on the linear approximation. In an optical information recording method for recording information on an optical information recording medium by converting recording data into recording pulses based on a write strategy,
Test recording of a specific pattern in which a fixed-length pit, a fixed-length land, and a variable-length pit continue on the optical information recording medium by different write strategies in which parameters related to the front phase shift of the recording pit of the write strategy are changed,
Reproducing the recording pattern recorded on the optical information recording medium by the test recording,
Detecting a phase shift amount of the front side of the recording pit from a deviation from a predetermined length of the fixed-length land of the fixed-length pit, fixed-length land, and variable-length pit in the reproduced reproduction pattern;
An optical information recording method comprising: determining an optimum write strategy based on the detected front phase shift amount. In an optical information recording method for recording information on an optical information recording medium by converting recording data into recording pulses based on a write strategy,
Test recording of a specific pattern in which a variable-length pit, a fixed-length land, and a fixed-length pit are continued on the optical information recording medium at least twice by a different write strategy in which a parameter relating to a rear phase shift of the recording pit of the write strategy is changed. ,
Reproducing the recording pattern recorded on the optical information recording medium by the test recording,
Detecting a rear phase shift amount of the recording pit from a deviation from a predetermined length of the fixed-length land of the variable-length pit, fixed-length land, and fixed-length pit in the reproduced reproduction pattern;
An optical information recording method comprising: determining an optimum write strategy based on the detected rear side phase shift amount. In an optical information recording method for recording information on an optical information recording medium by converting recording data into recording pulses based on a write strategy,
Test recording of a specific pattern in which a variable length land, a fixed length pit, and a fixed length land follow the optical information recording medium at least twice by different write strategies in which parameters relating to recording pit deviation due to thermal interference of the write strategy are changed,
Reproducing the recording pattern recorded on the optical information recording medium by the test recording,
Detecting a pit shift amount due to thermal interference of the recording pit from a shift from a specified length of the fixed-length pit of a variable-length land, a fixed-length pit, and a pattern in which the fixed-length land continues in the reproduced playback pattern;
An optical information recording method comprising determining an optimum write strategy based on the detected pit deviation amount. In an optical information recording method for recording information on an optical information recording medium by converting recording data into recording pulses based on a write strategy,
The test recording of the specific pattern in which the fixed length land, the variable length pit, and the fixed length land follow on the optical information recording medium is performed at least twice by different write strategies in which the parameters relating to the deviation of the recording pit length of the write strategy are changed,
Reproducing the recording pattern recorded on the optical information recording medium by the test recording,
In the reproduced reproduction pattern, a fixed-length land, a variable-length pit, a deviation of the length of the recording pit is detected from a deviation from a specified length of the variable-length pit in a pattern followed by the fixed-length land,
An optical information recording method comprising: determining an optimum write strategy based on the detected length deviation amount. In an optical information recording apparatus having a strategy circuit for converting recording data into recording pulses based on a write strategy,
Test recording means for performing test recording of a specific pattern at least twice on the optical information recording medium capable of independently detecting a shift amount related to the parameter by different write strategies in which specific parameters of the write strategy are changed; ,
Reproducing means for reproducing the recording pattern recorded on the optical information recording medium by the test recording means;
A deviation detecting means for detecting a deviation amount related to the specific parameter of the write strategy based on the specific pattern in the reproduction pattern reproduced by the reproducing means;
An arithmetic expression deriving unit for obtaining a linear approximation formula for determining an optimal write strategy based on the shift amount detected by the shift detection unit;
A write strategy determining means for determining an optimal write strategy based on the linear approximation formula stopped by the arithmetic expression deriving means;
An optical information recording apparatus comprising: setting means for setting an optimum write strategy determined by the write strategy determining means in the strategy circuit. The deviation detecting means includes
7. A front phase shift amount corresponding to the variable length pit is detected from a shift from a specified length of the fixed length land of a specific pattern in which a fixed length pit, a fixed length land, and a variable length pit follow. Optical information recording device. The deviation detecting means includes
7. A rear phase shift amount corresponding to the variable length pit is detected from a shift from a specified length of the fixed length land of a specific pattern in which a variable length pit, a fixed length land, and a fixed length pit follow. The optical information recording apparatus described. The deviation detecting means includes
Detecting a pit shift amount due to thermal interference of the fixed-length pit corresponding to the variable-length land from a shift from a specified length of the fixed-length pit of a specific pattern followed by a variable-length land, a fixed-length pit, and a fixed-length land. The optical information recording apparatus according to claim 6. The deviation detecting means includes
7. The light according to claim 6, wherein a length shift amount of the variable length pit is detected from a shift from a predetermined length of the variable length pit of a specific pattern in which a fixed length land, a variable length pit, and a fixed length land follow. Information recording device. The arithmetic expression deriving means includes:
The optical information recording apparatus according to claim 6, wherein an approximate expression for determining the optimum write strategy is obtained from a deviation amount detected by the deviation detection unit based on a least square method. The arithmetic expression deriving means includes:
When the deviation amount in the test recording by the first write strategy S1 detected by the deviation detection means is D1, and the deviation amount in the test recording by the second write strategy S2 is D2, the simultaneous equations D1 = a × S1 + b
D2 = a × S2 + b
And a function using the calculated a and b and the output deviation amount D for correcting the initial output deviation S = (D−b) / a
Seeking
The light strategy determining means includes
The optical information recording apparatus according to claim 6, wherein the optimum write strategy is determined based on the function. The strategy determining means includes
The function S = (D−b) / a
The optical information recording apparatus according to claim 12, further comprising: a correction table obtained from step (a), wherein the optimum write strategy is determined based on the correction table.

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