JP4719724B2 - Optical disc recording method, optical disc recording / reproducing apparatus, and optical disc - Google Patents

Description

  The present invention relates to a technique for appropriately performing data recording on an optical disk using an organic dye.

  With respect to an optical disk using an inorganic material (for example, a Blu-ray standard recording optical disk), for example, the characteristics shown in FIG. Specifically, the horizontal axis represents the main power (recording power at the time of mark formation) Pw, and the left vertical axis represents DCJ (DC jitter [%], a curve connecting the filled diamonds). The vertical axis on the right represents the asymmetry value (Asym, a curve connecting white rectangles). DCJ is the standard deviation of the phase difference between the binarized RF signal obtained by binarizing the RF signal and the clock signal generated from the binarized RF signal. The asymmetry value is an evaluation index representing the symmetry of amplitude between the shortest recording mark and the shortest space and the longest recording mark and the longest space in the RF signal.

  As shown in FIG. 1, the DCJ has a curve like a quadratic function that becomes the minimum when the main power Pw is about 5.4 mW, and the asymmetry value increases almost linearly as the main power Pw increases. To do. For optical discs using such inorganic materials, if there is a problem with detecting the asymmetry value (or β value, either asymmetry value or β value is used; the same applies hereinafter), the main power If Pw is adjusted according to the curve shown in FIG. 1, a desired asymmetry value (or β value) can be obtained. Therefore, for example, in WOPC (Walking OPC (Optimum Power Control)), the main power Pw is controlled using the asymmetry value as an evaluation index, and the disc internal and external differences such as the film thickness of the recording material, the reflective film thickness, the plate thickness, the warp, etc. It is possible to deal with disturbances caused by the drive, and disturbances of the drive such as temperature change of the laser diode and servo operation.

  On the other hand, with respect to a recording optical disk using an organic dye having an absorption spectrum at λ = 405 nm, for example, the characteristics shown in FIG. The horizontal axis and the vertical axis are the same as those in FIG. Although DCJ has a different value, it has a curve like a quadratic function in the case of an organic dye as in the case of an inorganic material, but the asymmetry value is the same as that of the inorganic material shown in FIG. No linearity is seen. That is, the asymmetry value (or β value) cannot determine whether or not an appropriate main power Pw is set.

  Japanese Patent Laid-Open No. 2000-200238 discloses a writable optical disc in which recording pulse standard conditions for specifying position information of a recording pulse for each of a plurality of possible combinations of mark length and space length are recorded in advance. Discloses a technique for reading out the recording pulse standard condition from the standard, correcting the recording pulse standard condition, and obtaining the optimum recording pulse condition. Specifically, using the position information for all combinations of mark length and space length under the recording pulse standard condition, the first trial writing is performed on the optical disc, the first trial writing is reproduced, and the reproduction signal is used. First jitter is detected, and a first predetermined amount of change is uniformly added to the position information for all mark length and space length combinations under the recording pulse standard conditions, and the uniformly changed position information is used on the optical disc. The second trial writing is performed, the second trial writing is reproduced, the second jitter is detected from the reproduced signal, the first jitter is compared with the second jitter, and the positional information used for the trial writing with the smaller jitter The recording pulse condition for selecting is obtained.

Japanese Unexamined Patent Application Publication No. 2007-103006 discloses a technique for reducing the influence of characteristic variations of a writable optical disc and an optical recording / reproducing apparatus. Specifically, the recording power parameter for the shortest recording mark is changed, trial writing is performed on the optical disc, the trial writing is reproduced, and after selecting the recording power parameter that improves the reproduction signal quality, the shorter mark length is selected. Thus, the recording power parameter for the mark length is changed, test writing is performed on the optical recording medium, the test writing is reproduced, and the recording power parameter for improving the reproduction signal quality is selected at least once.
Japanese Patent Laid-Open No. 2000-200408 JP 2007-103006 A

  Both of the above publications disclose techniques for calculating an optimum strategy for data recording, and use DCJ and error rate as indices. However, in the above publication, only the signal quality is pursued, and the β value and the asymmetry value when the write power changes are not mentioned. That is, the problem in adjusting the main power Pw by evaluating the asymmetry value or β value for the optical disk using the organic dye as described above is not considered.

  As described above, when adopting an optical disk using an organic dye, the conventional strategy or the like has been adopted, and the evaluation index such as the asymmetry value or β value is used for the disturbance as described above. There is a problem that it cannot deal with.

  Further, when the detection accuracy of the asymmetry value or β value is low, the slope of the straight line representing the relationship between the asymmetry value or β value and the main power Pw needs to be large. In addition, the linearity of the straight line representing the relationship between the asymmetry value or β value and the main power Pw must be maintained.

  Therefore, an object of the present invention is to provide a technique for making the relationship between the asymmetry value, the β value, and the main power Pw represented by an appropriate straight line when recording on an optical disk using an organic dye. Is to provide.

  Another object of the present invention is to provide a technique for maintaining the linearity of a straight line representing the relationship between the asymmetry value and β value and the main power Pw when recording on an optical disk using an organic dye. Is to provide.

  An optical disc recording method according to the first aspect of the present invention includes a step of reading a media ID of an optical disc to be recorded, and an optical disc using an organic dye having a read media ID having an absorption spectrum at λ = 405 nm. A setting step for setting the pulse length of the write pulse for forming the shortest mark to be the shortest within a range satisfying a predetermined condition for the index value related to the recording characteristics; including.

  According to the non-obvious knowledge of the inventor of the present application, by setting the pulse length of the write pulse to form the shortest mark so as to satisfy the conditions described above, the asymmetry value, β value, and main power are set. The relationship with Pw is represented by an appropriate straight line.

  Note that the predetermined condition for the index value relating to the recording characteristic described above is a condition that the DC jitter is equal to or less than a predetermined threshold value, and the write power that causes the DC jitter to be equal to or smaller than a predetermined second threshold value. There may be one of a condition that the width is greater than or equal to a predetermined value, a condition that the asymmetry value is less than a predetermined threshold value, and a condition that the β value is less than a predetermined threshold value. As described above, if the pulse length of the write pulse for forming the shortest mark is minimized while maintaining a constant recording quality, the main power Pw can be appropriately adjusted.

  In addition, the setting step described above may include a step of setting the bias power Pbw higher than the read power Pr.

  An optical disk recording method according to a second aspect of the present invention includes a step of reading a media ID of an optical disk to be recorded, and an optical disk using an organic dye having a read medium ID having an absorption spectrum at λ = 405 nm. In this case, the pulse length of the write pulse for forming the shortest mark is set in advance so that the margin of the recording characteristic, which is the width of the write power satisfying the predetermined index value related to the recording characteristic, is set in advance. And a setting step for setting so that the slope of the tangent of the curve representing the relationship between the margin of the recording characteristic and the pulse length of the write pulse is within a positive range.

  According to the non-obvious knowledge of the inventor of the present application, the relationship between the asymmetry value and β value and the main power Pw is appropriate by setting the pulse length of the write pulse for forming the shortest mark as short as described above. It will be represented by a straight line.

  Note that the index value related to the recording characteristics described above may be a DC jitter, an asymmetry value, or a β value. However, other indicators relating to recording characteristics may be used.

  Furthermore, the setting step described above may include a step of setting the bias power Pbw higher than the read power Pr.

  An optical disc recording method according to a third aspect of the present invention includes a step of reading a media ID of an optical disc to be recorded, and an optical disc using an organic dye having a read media ID having an absorption spectrum at λ = 405 nm. The pulse length 2Ttop of the write pulse for forming the shortest mark and the pulse length Tlp of the last pulse included when forming a mark longer than the shortest mark are 1.6. And a setting step for setting so that <2Ttop / Tlp <2.4.

  According to the non-obvious knowledge of the inventor of the present application, when 2Ttop and Tlp hold the relationship as described above, the relationship between the asymmetry value or β value and the main power Pw is represented by an appropriate straight line. Will come to be.

  Note that the setting step described above may include a step of setting the bias power Pbw higher than the read power Pr.

  The optical disc recording / reproducing apparatus according to the fourth aspect of the present invention uses means for reading the media ID of the optical disc to be recorded with data, and the read media ID has an absorption spectrum at λ = 405 nm and uses an organic dye. Control means for setting the pulse length of the write pulse for forming the shortest mark to be the shortest value within a range satisfying a predetermined condition for the index value related to the recording characteristics when the optical disc indicates an optical disc And have. The data of the pulse length of the write pulse may be stored in the memory of the optical disk recording / reproducing apparatus or may be recorded on the optical disk.

  The optical disc recording / reproducing apparatus according to the fifth aspect of the present invention uses means for reading the media ID of the optical disc to be recorded with data, and the read media ID has an absorption spectrum at λ = 405 nm and uses an organic dye. If the optical disc indicates an optical disc, the pulse length of the write pulse for forming the shortest mark is the margin of the recording characteristic that is the write power width that satisfies the predetermined index value for the recording characteristic. Setting means for setting so as to fall within a range in which the slope of the tangent of the curve representing the relationship between the margin of the recording characteristics and the pulse length of the write pulse is positive and greater than a predetermined threshold value.

  The optical disc recording / reproducing apparatus according to the sixth aspect of the present invention uses means for reading the media ID of the optical disc to be recorded with data, and the read media ID has an absorption spectrum at λ = 405 nm and uses an organic dye. In the case of indicating an optical disc, the pulse length 2Ttop of the write pulse for forming the shortest mark and the pulse length Tlp of the last pulse included when forming a mark longer than the shortest mark are 1 Control means for setting so that .6 <2Ttop / Tlp <2.4.

  The optical disk according to the seventh aspect of the present invention is an optical disk having an absorption spectrum at λ = 405 nm and using an organic dye, in which the pulse length of a write pulse for forming the shortest mark is stored, The pulse length of the write pulse is the shortest value within a range that satisfies a predetermined condition for an index value related to recording characteristics. In this way, any optical disk recording / reproducing apparatus can perform appropriate data recording.

  The optical disc according to the eighth aspect of the present invention is an optical disc having an absorption spectrum at λ = 405 nm and using an organic dye, in which the pulse length of a write pulse for forming the shortest mark is stored, The pulse length of the write pulse is a write power width in which an index value relating to recording characteristics satisfies a predetermined condition, and a recording characteristic margin is a predetermined threshold or more and less than a maximum value, and the recording characteristic margin is This is in the range where the slope of the tangent of the curve representing the relationship with the pulse length of the write pulse is positive.

  An optical disc according to the ninth aspect of the present invention is an optical disc having an absorption spectrum at λ = 405 nm and using an organic dye, and has a pulse length 2Ttop of a write pulse for forming the shortest mark, The pulse length Tlp of the last pulse included when forming a long mark is stored, and 2Ttop and Tlp satisfy 1.6 <2Ttop / Tlp <2.4.

  A program for causing a processor to execute the optical disk recording method of the present invention can be created. The program can be a storage medium such as a flexible disk, an optical disk such as a CD-ROM, a magneto-optical disk, a semiconductor memory, a hard disk, or the like. It is stored in a non-volatile memory of a storage device or processor. In some cases, digital signals are distributed over a network. Note that data being processed is temporarily stored in a storage device such as a processor memory.

  According to the present invention, when recording is performed on an optical disk using an organic dye, the relationship between the asymmetry value or β value and the main power Pw can be represented by an appropriate straight line.

  In addition, according to another aspect of the present invention, when recording is performed on an optical disc using an organic dye, linearity representing a relationship between an asymmetry value or a β value and the main power Pw can be maintained. become able to.

[Principle of the present invention]
FIG. 3 schematically shows the waveform of a multi-pulse type recording pulse (Write Pulse). In FIG. 3C, when forming a space, a space forming power Ps that is a recording power necessary for forming the space is used, and when forming a mark, the main power Pw is used, and each pulse after the top pulse is used for a mark of 3T or more. A bias power Pbw is used in between, and a cooling pulse power Pc is used for a cooling pulse which is a downward pulse after the last pulse of the mark. 3A shows recording data (2T mark (P2T) and 8T mark (P8T)), and FIG. 3B shows a sampling signal waveform. The inventor of the present application increases linearity between the asymmetry value and the main power Pw as shown in FIG. 4 by increasing the bias power Pbw as shown in FIG. 3 even in the case of an optical disk using an organic dye. I found it non-trivial to have. In particular, it is preferable to set Pbw higher than the read power Pr during reproduction. Note that the pulse length of 2T is represented as 2Ttop. For example, the pulse length of the first pulse in the case of n (n is an integer of 3 or more) T is represented as nTtop (in FIG. 3, since it is an 8T mark, it is represented as 8Ttop). Further, the pulse length of an intermediate pulse generated at a mark of 3T or more is expressed as Tmp, and the pulse length of a cooling pulse is expressed as Tcl.

  In FIG. 4, the horizontal axis represents the main power Pw, the left vertical axis represents DCJ [%], and the right vertical axis represents the asymmetry value. There is no significant change in DCJ between before improvement (bias power Pbw is kept as it is) and after improvement (raise so that bias power Pbw> Pr), and there is almost no deterioration in recording quality. After the improvement, the relationship that the asymmetry value decreases as the main power Pw increases appears. In addition, in the case of inorganic materials, the polarity is high-to-low, so a straight line rising to the right as shown in FIG. 1 can be drawn, whereas in the case of an optical disk using an organic dye, low-to-high. Because of this polarity, a straight line going down to the right can be drawn.

More detailed data is shown in FIG. Here, β in each case of ε _bw = 0.254, ε _bw = 0.339, ε _bw = 0.424, and ε _bw = 0.508 when Pbw = Pw × ε _bw is set. This represents the relationship between the value and the main power Pw. The β value is obtained by AC coupling the RF signal, that is, when the DC component of the RF signal is removed and the GND level is used as a reference, and the difference between the amplitude of the longest recording mark M8T and the GND level is a. If the difference between the amplitude of the space S8T and the GND level is b, β = (ab) / (a + b). As can be seen from FIG. 5, in both cases, the relationship between the β value and the main power Pw can be approximated by a linear function.

Further detailed data is shown in FIG. In FIG. 6, the horizontal axis represents ε _bw or Pbw, the left vertical axis represents the scale of the bar graph, and the absolute value of the slope of each straight line in FIG. 5, and the right vertical axis represents the line graph. It represents a scale and represents the accuracy σ of each linear approximation in FIG. As can be seen from FIG. 6, the slope of the straight line increases as ε _bw increases. Further, when Pbw = 3.0, a larger inclination can be obtained. The larger the slope, the easier it is to control the recording power to an appropriate value even if the β value detection accuracy is low. Therefore, it is preferable to set Pbw to a fixed value instead of Pbw = Pw × ε _bw if possible. . In particular, when Pbw = 3.0 is fixed, the accuracy of linear approximation σ is also a large value, which is more preferable. However, there are cases where such settings cannot be made depending on the optical disc recording / reproducing apparatus, so fixing Pbw is not considered any further.

On the other hand, it can be seen that the accuracy σ of the linear approximation becomes worse as ε _bw increases. This is considered to be a phenomenon that occurs when a long mark is recorded too strongly when the bias power Pbw becomes too high. Therefore, with this as it is, ε _bw cannot be increased due to the accuracy σ of linear approximation, and the slope of the straight line cannot be sufficiently increased.

Here, the present inventors, as a method for improving greatly the slope to and linearity (i.e. the linear approximate accuracy sigma), non-trivially found that shortening the pulse length 2Ttop of a 2T mark as a shortest mark. In this way, by setting the pulse length of the shortest mark to be short, the rate of change of energy given to the shortest mark when the main power Pw is changed is compared with the case where the pulse length of the write pulse forming the shortest mark is long. Therefore, the amplitude change corresponding to the shortest mark is likely to occur, and the followability of the β value and the asymmetry value with respect to the main power Pw is improved.

FIG. 7 shows the main power Pw in each case of 2Ttop = 1.000T (T is one cycle of the sampling clock), 2Ttop = 0.938T, 2Ttop = 0.875T, 2Ttop = 0.814T, 2Ttop = 0.551T. The relationship with β value is shown. FIG. 8 shows specific values for 2Ttop, β characteristics (slope of a straight line representing the relationship between the main power Pw and β value shown in FIG. 7), and σ representing the degree of variation when linear approximation is performed. Based on the data of FIG. 7 and FIG. 8, when compared with 2Ttop = 1.000T, which is the conventional value, as 2Ttop becomes shorter, the β characteristic also increases, and σ is generally a preferable value (a value close to 1.0). . At this time, ε _bw (= Pb / Pbw) is set to 0.424, and ε _s (= Ps / Pw) is set to 0.254.

  However, FIG. 9 shows the relationship between the main power Pw and the DCJ. As the value of 2Ttop decreases, the value of the DCJ increases. Assuming that the DCJ threshold is 7%, in the case of 2Ttop = 0.551T, it is less than 7% in the best main power condition, but in other cases it is over 7%. Since it is necessary to vary the main power Pw, setting such as 2Ttop = 0.551T is not preferable from the viewpoint of recording characteristics. That is, for example, it is most preferable to make 2Ttop as short as possible within a range that satisfies a predetermined condition for DCJ.

  It can be said that it is preferable to set 2Ttop in a range satisfying a predetermined condition for a DCJ margin (a width of main power Pw such that DCJ is 7.5% or less, for example) as shown in FIG. 10 instead of DCJ. . In FIG. 10, the horizontal axis represents 2Ttop [T], and the vertical axis represents DCJ margin [mW] representing the width of the main power. Here, when the relationship between 2Ttop and the DCJ margin is plotted, a quadratic curve is obtained as shown in FIG. That is, 2Ttop becomes a maximum at about 0.91T, and the DCJ margin decreases even if 2Ttop becomes longer or shorter than that. In the conventional 2Ttop adjustment, the DCJ margin is usually maximized. However, in the present invention, as described above, shortening the 2Ttop results in a slightly worse DCJ margin, but the β value or asymmetry value and the main value are reduced. The slope and linearity of the straight line representing the relationship with the power Pw are preferable. Therefore, the allowable range in FIG. 10, that is, the DCJ margin is not less than a predetermined threshold (0.7 mW in FIG. 10) and less than the maximum value (maximum value), and the slope of the curve representing the relationship between 2Ttop and the DCJ margin is positive. By setting 2Ttop in a certain range, an effect can be obtained with respect to the slope and linearity of a straight line representing the relationship between the β value or asymmetry value and the main power Pw. That is, the main power Pw can be appropriately adjusted by the β value and the asymmetry value.

  Further, it was found that the relationship between 2Ttop and Tlp is as shown in FIG. In a normal state of 2Ttop = 1.000T, Tlp = 0.625T, and as 2Ttop becomes shorter, Tlp becomes shorter. In the Blu-ray standard, when the 2Ttop length is changed, the length of the rear portion (referred to as the end portion) of the 2T pulse changes. When the 2Ttop length is shortened as in the present invention, the end portion of the mark after 3T becomes longer than 2T. As a result, the characteristics such as DCJ and error rate are affected and the characteristics are deteriorated. Therefore, when the 2Ttop length is shortened, it is necessary to shorten the last pulse length Tlp in order to ensure the DCJ characteristics.

From the measurement results as shown in FIG. 11, in the present invention, as a range in which the 2Ttop length is set short,
1.6 <2Ttop / Tlp <2.4
Is a range in which the β value and the asymmetry value linearly follow the change in the main power Pw while satisfying the DCJ characteristics.

  As described above, the range is set by 2Ttop and Tlp, but may be defined by other pulses (Tmp, 3Ttop, and 4Ttop).

  In some cases, an asymmetry value or a β value is used as an index value for recording characteristics.

[Embodiment]
A functional block diagram of the drive system in the embodiment of the present invention will be described with reference to FIG. The drive system according to the embodiment of the present invention includes an optical disc recording / reproducing apparatus 100 and an input / output system (not shown) including a display unit such as a television receiver and an operation unit such as a remote controller.

  The optical disc recording / reproducing apparatus 100 includes a memory 127 that stores data in the middle of processing, data of processing results, reference data in processing, and the like, and a CPU that includes a memory circuit 126 in which a program for performing processing described below is recorded. A control circuit 125 including a central processing unit (Central Processing Unit), an interface unit (I / F) 128 that is an interface with an input / output system, and a maximum amplitude level or minimum amplitude of an RF signal that is a reproduction signal A characteristic value detection unit 124 that detects a level and the like, and a 2T to 8T code (for example, in the case of the Blu-ray standard. In the case of the Blu-ray standard, the synchronous code 9T is also identified. In the case of the DVD standard, 2T to 11T code and 13T of the synchronization code are identified). The data to be recorded outputted from the equalizer 131, the data demodulating circuit 123, the pickup unit 110, and the control circuit 125 for performing a process for decoding the data is subjected to predetermined modulation, and a laser diode ( LD) includes a data modulation circuit 129 for output to the driver 121, an LD driver 121, a rotation control unit and a motor for the optical disc 150, a servo control circuit 132 for the pickup unit 110, and the like.

  The pickup unit 110 includes an objective lens 114, a beam splitter 116, a detection lens 115, a collimator lens 113, an LD 111, and a photodetector (PD) 112. In the pickup unit 110, an actuator (not shown) operates in accordance with control of a servo control unit (not shown), and focusing and tracking are performed.

  The control circuit 125 is connected to the memory 127, the characteristic value detection unit 124, the I / F 128, the LD driver 121, the data modulation circuit 129, the servo control circuit 132, a rotation control unit (not shown), and the like. In addition, the characteristic value detection unit 124 is connected to the PD 112, the control circuit 125, and the like. The LD driver 121 is connected to the data modulation circuit 129, the control circuit 125, and the LD 111. The control circuit 125 is also connected to the input / output system via the I / F 128.

  Next, an outline of processing when data is recorded on the optical disc 150 will be described. First, the control circuit 125 causes the data modulation circuit 129 to perform a predetermined modulation process on the data to be recorded on the optical disc 150, and the data modulation circuit 129 outputs the data after the modulation process to the LD driver 121. The LD driver 121 drives the LD 111 with the received data according to designated recording conditions (strategies and parameters) to output laser light. The laser light is irradiated onto the disk 150 through the collimating lens 113, the beam splitter 116, and the objective lens 114, thereby forming marks and spaces on the optical disk 150.

  An outline of processing when data recorded on the optical disc 150 is reproduced will be described. In accordance with an instruction from the control circuit 125, the LD driver 121 drives the LD 111 to output laser light. The laser light is irradiated onto the optical disc 150 through the collimating lens 113, the beam splitter 116, and the objective lens 114. The reflected light from the optical disk 150 is input to the PD 112 via the objective lens 114, the beam splitter 116, and the detection lens 115. The PD 112 converts the reflected light from the optical disc 150 into an electrical signal and outputs it to the characteristic value detection unit 124 and the like. The equalizer 131 and the data demodulating circuit 123 perform predetermined decoding processing on the output reproduction signal, and the decoded data is sent to the display unit of the input / output system via the control circuit 125 and the I / F 128. Output and display the playback data. The characteristic value detection unit 124 is not used in normal reproduction.

  Next, the operation of the optical disc recording / reproducing apparatus 100 will be described with reference to FIG. First, the control circuit 125 reads out the media ID recorded on the optical disc 150 by reproducing it through the PD 112, the equalizer 131, and the data demodulation circuit 123 (step S1). Then, the control circuit 125 reads various strategy data corresponding to the read media ID from the memory 127 and sets the LD driver 121 (step S3). When the data is recorded not on the memory 127 but on the optical disc 150, various strategy data are read from the optical disc 150. When the media ID of the optical disk using the organic dye is read, in this step, 2Ttop and Tlp setting data according to the principle of the present invention are read from the memory 127 and set in the LD driver 121. Is done.

  Then, a known process for optimizing the main power Pw is performed (step S5). At this time, the characteristic value detection unit 124 detects a characteristic value for calculating an asymmetry value or a β value and outputs it to the control circuit 125. The control circuit 125 calculates an asymmetry value or β value to calculate an optimum main power Pw.

  Thereafter, the control circuit 125 sets the optimum main power Pw calculated in step S5 in the LD driver 121 and performs data recording (step S7).

  By performing such processing, the effects described in the column of the principle of the invention can be obtained, and furthermore, the main power Pw can be appropriately controlled also in WOPC (Walking Optimum Power Control) or the like. It becomes like this.

  Note that 2Ttop and Tlp setting data that satisfy the conditions described in the section of the principle of the present invention may be stored in the memory 127 or in the optical disk 150. When it is held on the optical disc 150, it is held in the Lead-in area as shown in FIG. The lead-in area is largely divided into a system lead-in area, a connection area, and a data lead-in area. The system lead-in area includes an initial zone, a buffer zone, a control data zone, and a buffer. -Includes zones. The connection area includes a connection zone. Further, the data lead-in area includes a guard track zone, a disc test zone, a drive test zone, a guard track zone, an RMD duplication zone, a recording management zone, an R-physical format information zone, and a reference code. -Includes zones. In the present embodiment, the recording condition data zone 170 is included in the control data zone of the system lead-in area. For example, the recording condition data zone 170 holds 2Ttop, Tlp, etc. that satisfy the conditions described in the section of the principle of the present invention.

  Although the embodiment of the present invention has been described above, the present invention is not limited to this. For example, the functional block diagram of FIG. 13 is shown for explaining the embodiment, and may not necessarily match an actual circuit or module configuration. In addition, as for the processing flow, as long as the processing result is the same, the processing order may be changed, or the processing order may be executed in parallel.

It is a figure showing the relationship between the main power Pw of an optical disk using an inorganic material, DCJ, and an asymmetry value. It is a figure showing the relationship between the main power Pw of the optical disk using an organic pigment | dye, DCJ, and an asymmetry value at the time of measuring using the conventional strategy data. It is a figure for demonstrating waveforms, such as recording power. It is a figure which shows the improvement degree of the curve showing the relationship between the main power Pw and the asymmetry value at the time of raising bias power Pbw. It is a figure for demonstrating the relationship between main power Pw at the time of changing bias power Pbw and (beta) value. It is a figure for comparing the case where (epsilon) _bw is changed and the case where bias power Pbw is fixed about the inclination of the straight line showing the relationship between main power Pw and (beta) value, and the precision of a linear approximation. It is a figure showing the relationship between main power Pw at the time of changing 2Ttop and (beta) value. It is a figure showing the specific numerical value of FIG. It is a figure showing DCJ in the case of FIG. It is a figure showing the relationship between 2Ttop and a DCJ margin. It is a figure showing the relationship between 2Ttop and Tlp. It is a functional block diagram in an embodiment of the present invention. It is a figure which shows the processing flow in embodiment of this invention. It is a figure which shows the data structure stored in an optical disk.

Explanation of symbols

100 Optical Disc Recording / Reproducing Device 110 Pickup Unit 111 LD
112 PD 113 Collimating lens 114 Objective lens 115 Detection lens 116 Beam splitter 121 LD driver 123 Data demodulating circuit 124 Characteristic value detection unit 125 Control circuit 126 Memory circuit 127 Memory 128 I / F 129 Data modulation circuit 131 Equalizer 132 Servo control circuit 150 optical disc

Claims (3)

Reading the media ID of the optical disc to be recorded;
When the read media ID indicates an optical disk having an absorption spectrum at λ = 405 nm and using an organic dye, the pulse length of the write pulse for forming the shortest mark is the recording characteristic. A setting step for setting the index value to be the shortest value within a range that satisfies a predetermined condition;
Only including,
The width of the main power is within a range in which the predetermined condition for the index value related to the recording characteristic is equal to or less than a predetermined threshold value for DC jitter and the range in which the DC jitter is equal to or smaller than a predetermined second threshold value. One of the conditions of being equal to or greater than a predetermined value,
The setting step includes
Setting the bias power Pbw higher than the read power Pr
An optical disc recording method including : Means for reading the media ID of the optical disk to be recorded;
When the read media ID indicates an optical disk having an absorption spectrum at λ = 405 nm and using an organic dye, the pulse length of the write pulse for forming the shortest mark is the recording characteristic. Control means for setting the index value for the index value to be the shortest value within a range that satisfies a predetermined condition;
I have a,
The width of the main power is within a range in which the predetermined condition for the index value related to the recording characteristic is equal to or less than a predetermined threshold value for DC jitter and the range in which the DC jitter is equal to or smaller than a predetermined second threshold value. One of the conditions of being equal to or greater than a predetermined value,
The control means is
An optical disc recording / reproducing apparatus that sets the bias power Pbw higher than the read power Pr . An optical disc having an absorption spectrum at λ = 405 nm and using an organic dye,
The pulse length of the write pulse for forming the shortest mark and the parameter for setting the bias power Pbw higher than the read power Pr are stored.
Pulse length of the write pulses, Ri shortest value der satisfying a condition within a predetermined range for the index value related to the recording characteristics,
The width of the main power is within a range in which the predetermined condition for the index value related to the recording characteristic is equal to or less than a predetermined threshold value for DC jitter and the range in which the DC jitter is equal to or smaller than a predetermined second threshold value. An optical disc that is in one of the conditions that it is equal to or greater than a predetermined value .

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