JP2011134402A - Optical disk recording device and method for recording on write-once optical disk - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical disk recording device with which a suitable recording parameter can be determined, while reducing the number of recording tests. <P>SOLUTION: In the optical disk recording device with which information is recorded by forming a mark and a space on an optical disk having test regions for recording tests on the inner periphery and the outer periphery respectively, the optical disk recording device has: a recording test part 130 to conduct the recording test with recording speed of at least one level of recording speed of multiple levels, in the test region of the optical disk; a parameter determining part 118 to determine a recording parameter based on the result of the recording test conducted by the recording test part; and a parameter calculation part 118 to calculate a recording parameter in recording with recording speed for which the recording test has not been conducted in reference to the determined recording parameter. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an optical disc recording apparatus and a write-once optical disc recording method that can determine recording parameters.

  As data-writable optical discs, DVD ± R, DVD ± RW, DVD-RAM, Blu-ray disc, CD-R, CD-RW, and the like are known.

  These optical disks record information by forming marks and spaces with a laser diode. However, due to the difference in characteristics of each optical disc, it is necessary to change an appropriate recording parameter at the time of recording, for example, write strategy (hereinafter referred to as WST) and recording power. For a general optical disk that is often distributed in the market, an appropriate write strategy and recording power are obtained in advance and stored in the optical disk recording apparatus in advance. The write strategy and recording power stored in advance are appropriately set according to the type of the optical disc at the time of recording, and an optimum recording process is performed.

  However, there are many optical discs in addition to the optical discs of major manufacturers that are pre-adjusted in the market, and new types of optical discs have been introduced to the market after the sale of optical disc recording devices. Yes. Therefore, it is not possible to specify appropriate recording parameters for all optical discs in advance and store them in the optical disc recording apparatus.

  Therefore, when recording on an unknown optical disc for which an appropriate recording parameter is not set, a technique for performing a recording test on a test area provided on the optical disc and setting an appropriate recording parameter is known (for example, , See Patent Document 1). In particular, in the invention described in Patent Document 1, when the recording speed (linear velocity) is increased to 2 times, 4 times, 8 times,..., An appropriate recording parameter is determined using a test area provided on the outer periphery of the optical disk. To do.

Japanese Patent Laid-Open No. 2004-199840

  However, in the invention described in Patent Document 1, a recording test is performed in the test area for all recording speeds, and appropriate recording parameters are determined. This makes it impossible to determine an appropriate recording parameter as the recording speed increases. This is because the capacity of the test area is limited and the number of write tests that can be performed is also limited.

  In addition, if an appropriate recording parameter is determined at all recording speeds, the time required for the determination becomes long. This does not meet the user's general desire to shorten the recording time.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an optical disc recording apparatus and a write-once optical disc recording method that can determine appropriate recording parameters while reducing the number of recording tests.

  The optical disc recording apparatus of the present invention records information by forming marks and spaces on an optical disc having test areas for recording tests on the inner circumference and the outer circumference, respectively. The optical disc recording apparatus includes a recording test unit, a parameter determination unit, and a parameter calculation unit. The recording test unit performs a recording test on the test area of the optical disc at a recording speed of at least one of the multi-stage recording speeds. The parameter determination unit determines a recording parameter based on a recording test result by the recording test unit. The parameter calculation unit calculates a recording parameter when recording is performed at a recording speed at which a recording test is not performed, using the determined recording parameter as a reference.

  The above optical disc recording apparatus determines an optimum recording parameter from a recording test executed at an arbitrary recording speed, and further uses the determined recording parameter to perform recording at a recording speed at which no recording test is performed. Determine recording parameters.

  Even if the recording test is not performed at all recording speeds, the optimum recording parameters at all recording speeds can be determined within the capacity of the existing test area. Since the recording test is not performed at all recording speeds, the number of recording tests can be reduced, and as a result, the total recording time can be reduced.

It is a block diagram for demonstrating the optical disk recording device which concerns on embodiment of this invention. It is a top view for demonstrating the structure of the write-once type optical disk shown by FIG. 3 is a flowchart showing a flow of operations of the optical disc recording apparatus 100 according to the first embodiment. It is a graph which shows the relationship between a write strategy and recording speed. It is a figure which shows the pulse after the strategy conversion with respect to a reference | standard pulse. It is a flowchart which shows the flow of operation | movement of the optical disk recording device which concerns on 2nd Embodiment. It is a figure which shows calculation of the corrected amount of a reference | standard WST function type | formula. It is a figure which shows the concept which correct | amends a reference | standard WST function type | formula. It is a flowchart which shows the flow of operation | movement of the optical disk recording device which concerns on 3rd Embodiment. It is a figure which shows the concept which correct | amends a reference | standard WST function type | formula. It is a flowchart which shows the flow of operation | movement of the optical disk recording device which concerns on 4th Embodiment. It is a flowchart which shows the flow of operation | movement of the optical disk recording device which concerns on 5th Embodiment. It is a figure which shows the concept which adjusts a recording parameter during recording to a data area. It is a figure which shows the concept which sets the recording parameter in the recording speed higher than the recording speed which performed the recording test.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In the description of the drawings, the same elements are denoted by the same reference numerals, and redundant description is omitted. In addition, the dimensional ratios in the drawings are exaggerated for convenience of explanation, and may be different from the actual ratios.

  FIG. 1 is a block diagram for explaining an optical disk recording apparatus according to an embodiment of the present invention, and FIG. 2 is a plan view for explaining the structure of a write-once optical disk shown in FIG.

  An optical disk recording apparatus 100 according to an embodiment of the present invention is used for recording information on an optical disk 10 by a semiconductor laser and reproducing recorded information. As shown in FIG. , Head amplifier 104, binarization circuit 106, clock shift measurement unit 108, measurement value storage unit 110, data discrimination / calculation unit 112, WST (write strategy) storage unit 114, base WST storage unit 116, WST calculation unit 118, A decoder 120, an encoder 122, a recording pulse adjustment unit 124, a laser driving unit 126, and a control unit 130 are included.

  The optical disc 10 is a write-once type such as a DVD + R, and has an inner test area 12, a data area 14, and an outer test area 16, as shown in FIG. The data area 14 is an area where information is recorded by CAV (constant angular velocity). The inner and outer test areas 12 and 16 are areas used for adjusting recording parameters for recording information in the data area 14. For example, the inner test area 12 is arranged in a PCA (Power Calibration Area) area located inside the lead-in area, and the outer test area 16 is arranged in a PCA area located outside the lead-out area. The recording parameters are, for example, recording power and write strategy (WST). The optical disc 10 stores its own unique information. The unique information is, for example, a disk ID, and the manufacturer and model number of the optical disk 10 can be specified.

  The optical pickup 102 is a recording unit that records information in the data area 14 by CAV, and includes a laser light source, an optical component, and a photodetector. The laser light source is, for example, a laser diode. The optical component is a collimator lens, an objective lens driven by a focus actuator or a tracking actuator, a polarizing beam splitter, a cylindrical lens, or the like. The photodetector is divided into four regions and used to convert light into an electrical signal. The optical pickup 102 can also have a front monitor diode that monitors the laser output during recording and reproduction.

  The head amplifier 104 is used to generate an RF signal (data signal), a focus error signal, and a tracking error signal. The RF signal is a signal indicating the total amount of reflected light to each divided region of the photodetector, and is generated by detecting reflected light from the optical disc 10 and calculating the reflected light amount based on the reflected light. The focus error signal is a signal for detecting the defocus of the irradiation laser of the optical pickup 102, and is generated by, for example, the astigmatism method. The tracking error signal is a signal for detecting a track shift of the irradiation laser of the optical pickup 102, and is generated by, for example, a push-pull method.

  The binarization circuit 106 is a reproduction signal generation circuit that forms a detection signal from the head amplifier 104 and generates a binary digital signal corresponding to the mark and space. For example, the binarization circuit 106 includes 3T, 4T, 5T,. . . The threshold for changing the analog signal to a binarized square wave is constantly adjusted.

  The clock shift measuring unit 108 is used to measure an edge shift (dT) between the digital signal generated by the binarization circuit 106 and the reference clock generated by the decoder 120.

  Further, the clock shift measuring unit 108 is also used to calculate a determination parameter and a mark edge change amount. The determination parameter is defined by the deviation between the edge of the detection signal (binary digital data) acquired from the binarization circuit 106 and the clock edge, and whether to change the reference write strategy (referred to as base WST). Used to adjust whether or not. The mark edge change amount is a mark edge change amount actually measured when the reproduction signal is recorded with a different WST and moved by a specified amount (ΔT). The different WSTs are, for example, a base WST for trial writing in the test area and a base WST + α.

  The measurement value storage unit 110 includes, for example, a high-speed random access storage device (RAM), and is used to temporarily store data measured by the clock shift measurement unit 108. The stored data is the amount of clock shift of various signals and the signal type.

  The data discrimination / calculation unit 112 is used for discriminating data stored in the measurement value storage unit 110 (measurement data in the clock shift measurement unit 108) for each signal and executing various calculations. The target of calculation is a deviation based on the ratio of the number of samples of various signals, a deviation amount (deviation) from the theoretical center value of each signal distribution, a time difference jitter (Data-Clock jitter), a correlation function based on a mark edge change amount, and thermal interference. It is the influence of adjacent edges due to the effect.

  The WST storage unit 114 includes, for example, an EEPROM (electrically erasable PROM, Electrically Erasable PROM), and is used to temporarily store the WST calculated by the WST calculation unit 118. The WST storage unit 114 is used to temporarily store not only the WST but also the recording power calculated by the WST calculation unit 118.

  The base WST storage unit 116 includes, for example, a read-only nonvolatile storage device (ROM), and stores reference recording parameters used in the WST calculation unit 118, for example, base WST and base recording power. The base WST and the base recording power are pre-calculated and prepared by the strategy designer, and are the default WST and recording power associated with the specific information of the optical disc 10.

  As a parameter determination unit, the WST calculation unit 118 determines an optimum recording parameter based on the result of the recording test. Further, the WST calculation unit 118 calculates, as a parameter calculation unit, an optimum recording parameter when recording is performed at a recording speed at which a recording test is not performed on the basis of the determined recording parameter. The detailed operation of the WST calculation unit 118 will be described later.

  The decoder 120 is a circuit that converts the binarized signal generated by the binarization circuit 106 into a reproduction signal having a predetermined format and outputs the signal. The encoder 122 is a circuit that converts a recording signal into, for example, an EFM (Eight to Four Modulation) signal and outputs the signal to the recording pulse adjustment unit 124.

  The recording pulse adjustment unit 124 is used to form a recording pulse train based on the optimum recording parameters set in the WST calculation unit 118 and to output it to the laser driving unit 126.

  The laser driving unit 126 generates a pulse signal for driving a laser light source (for example, a laser diode) of the optical pickup 102 according to the recording pulse train from the recording pulse adjusting unit 124, and outputs the pulse signal to the optical pickup 102.

  The control unit 130 controls the recording operation and the reproducing operation of the optical disc apparatus 100. More specifically, the control unit 130 has a function of determining the maximum recording speed from the WST test result in addition to the normal recording operation and reproduction operation. In addition, as a recording test unit, each configuration of the optical disc recording apparatus 100 is controlled, and a recording test is performed on the test area of the optical disc 10 at an arbitrary recording speed of at least one of the multi-stage recording speeds.

  The optical disk recording apparatus 100 according to the embodiment of the present invention can determine recording parameters at each recording speed without performing a writing test for all of the multi-stage recording speeds (angular speed of the optical disk 10).

  Hereinafter, an embodiment of the operation of the optical disc recording apparatus 100 will be described.

(First embodiment)
3 is a flowchart showing the flow of the operation of the optical disc recording apparatus 100 according to the first embodiment, FIG. 4 is a graph showing the relationship between the write strategy and the recording speed, and FIG. 5 is a diagram showing the pulse after the strategy conversion with respect to the reference pulse. is there. In FIG. 4, the horizontal axis represents the recording speed on the optical disc 10, and the vertical axis represents WST.

  The optical disc recording apparatus 100 executes a recording test on the test area at two or more stages of recording speeds on the optical disk 10 (step S1). Here, in the present embodiment, a recording test on the optical disc 10 is executed at the recording speeds V1, V2, V3, and V4. For example, a 6 × speed recording test is executed in the inner test area 12, and an 8, 12, 16 × speed recording test is executed in the outer test area 16.

  Subsequently, the optical disc recording apparatus 100 determines the optimum recording parameter (WST) at the recording speeds V1, V2, V3, and V4 based on the result of the recording test (step S2). The determination of the optimal recording parameter is not particularly limited. For example, after setting the base WST, calculating the temporary optimal WST based on the set base WST, and performing test recording (trial writing) with the temporary optimal WST. The quality can be measured and compared with the specified value of the evaluation item. If the specified value is not satisfied, the WST can be reviewed and the base WST can be set again. The evaluation items of the recording quality include, for example, a deviation based on a sample number ratio of various signals processed in the data discrimination / calculation unit 112, a deviation amount (deviation) from the theoretical center value of each signal distribution, and a time difference jitter (Data-Clock). Jitter), a correlation function based on a mark edge change amount, and an influence of adjacent edges due to a thermal interference effect.

  The optical disc recording apparatus 100 plots the recording speeds V1 to V4 and the optimum WST1 to 4 at that time as coordinates indicated by large white circles in FIG. 4, and sets the WST to the recording speed so as to connect these coordinates. A function expression as a function is created (step S3).

  Furthermore, the optical disc recording apparatus 100 substitutes the recording speeds Va, Vb, Vc for which the recording test has not been performed into the created function formula, and calculates the optimum WST for the recording speeds Va, Vb, Vc (step S4). ). Here, the recording speeds Va, Vb, and Vc are recording speeds set between V1 and V2 in accordance with the resolution (for example, 0.5 times) of the recording speed. Although not shown, there may be a recording speed set with a predetermined resolution between V2, V3 and V4.

  The WST is stored as a set of various parameter tables. As one of the parameters constituting the table, the WST includes, for example, a table for the delay amount with respect to the reference pulse timing for each of the 3T to 11T marks and the 14T marks. The delay amount of the 3T pulse will be described with reference to FIG. As shown in FIG. 5, the rise and fall timing of each pulse in WST is determined by the delay amount (DL, DT) from the reference pulse (Ref Pulse). A functional expression is created so that the delay amount (DL) of the 3T pulse rising edge with respect to the reference pulse gradually changes from WST1 to WST2, from WST2 to WST3, and from WST3 to WST4. As described above, it can be said that the WST represented on the vertical axis in FIG. 4 is represented as a change amount of a numerical value (a parameter such as a pulse delay amount) of the table constituting the WST. Therefore, if the recording speed Va is substituted into the function indicated by the dotted line in FIG. 4, WST1 'whose delay amount is slightly closer to WST2 than WST1 is calculated.

  As described above, in the first embodiment, optimum WST1 to WST4 are determined in four stages of recording speeds V1, V2, V3, and V4, and a recording test is performed using the determined WST1 to WST4. The WST for recording at a recording speed a, b, or c is determined. Therefore, even if the recording test is not performed at all recording speeds, the optimum recording parameter reflecting the actual recording test result can be determined. Further, since the number of recording tests can be reduced, the optimum WST can be determined at all recording speeds even with the capacity of the existing inner test area 12 and outer test area 16. In addition, since the recording test is not performed at all recording speeds, the number of recording tests can be reduced, and as a result, the total recording time can be reduced.

  In the above embodiment, only the example of changing the WST as the recording parameter is shown, but the present invention is not limited to this. Recording power can also be adjusted as a recording parameter. In this case, the optimum recording power is calculated at four stages of recording speeds V1, V2, V3, and V4, and these are plotted to calculate a functional equation. Using the functional equation, the optimum recording power at other speeds is calculated. Is also calculated.

  In the above embodiment, the recording test is performed for the recording speeds V1, V2, V3, and V4. However, the present invention is not limited to this. A recording test may be performed for any other recording speed. The recording test may be performed at a recording speed of any two or more stages instead of four stages. However, since the recording time cannot be shortened by executing the recording test at all the recording speeds, the recording test is not performed for all the stages. The recording test may be performed only in the outer test area 16.

(Second Embodiment)
In the first embodiment, a recording test is performed at two or more recording speeds, a function equation connecting (recording speed, recording parameter) coordinates is calculated from the recording test result, and the recording test is not performed using the function equation. Recording parameters for recording speed were calculated. However, in the second embodiment, the recording test is performed only at the two recording speeds, and the recording parameters of the recording speeds not subjected to the recording test are calculated.

  FIG. 6 is a flowchart showing an operation flow of the optical disc recording apparatus according to the second embodiment, FIG. 7 is a diagram showing calculation of a correction amount of the reference WST function equation, and FIG. 8 is a diagram showing a concept of correcting the reference WST function equation It is.

  First, the case where WST is calculated as a recording parameter will be described.

  The optical disc recording apparatus 100 executes a recording test on the test area at two recording speeds among the recording speeds on the optical disc 10 (step S11). In the following, a case where the recording test is executed in two stages of the lowest recording speed Vmin and the highest recording speed Vmax will be described.

  Subsequently, the optical disc recording apparatus 100 determines the optimum recording parameter (WST) at the recording speed Vmin, max based on the result of the recording test (step S12). The determination of the optimum recording parameter based on the recording test is the same as in the first embodiment.

  The optical disc recording apparatus 100 plots the recording speed Vmin, max and the optimum WST at that time as coordinates as shown by a large black circle in FIG. 7 (step S13).

  Subsequently, the optical disc recording apparatus 100 proportionally corrects the base WST function equation (reference function equation) stored in advance in the base WST storage unit 116 based on the plotted (recording speed, WST) coordinates (step S14). ). Proportional correction is to correct between Vmin and Vmax of the base WST function formula so that WST at Vmin and Vmax of the base WST function formula becomes WST at the plotted Vmin and Vmax. In FIG. 7, the base WST and the correction WST are connected with a straight line with respect to Vmin and Vmax, and the correction amount of WST is calculated for V1, V2, and V3 between them.

  As shown in FIG. 8, the optical disc recording apparatus 100 adds the WST correction amount (ΔWST1) calculated in FIG. 7 to the base WST to determine the correction strategy in V1. Similarly for V2, V3, and V4, the correction amount obtained in FIG. 7 is added to the base strategy to determine the optimum WST at each speed. (Step S15).

  Although an example of calculating the WST has been described above, the recording power that is another recording parameter can be similarly calculated. The vertical axis of the graphs of FIGS. 7 and 8 may be changed to the recording power, and the same calculation as the WST correction may be performed.

  As described above, in the second embodiment, the recording test is performed only at the two recording speeds, and the recording parameters are calculated by substituting the other recording speeds into the corrected base recording parameter function formula. You can save time. Further, the use of the existing reference function formulas such as the base WST function formula and the base recording power function formula also contributes to shortening of the recording time.

  In step S11, a recording test was performed in two stages, the lowest recording speed Vmin and the highest recording speed Vmax. However, it is not limited to this. Recording tests may be performed for the other two stages of recording speed.

(Third embodiment)
In the first embodiment, a recording test is performed at two or more recording speeds, and recording parameters at other recording speeds are also calculated. However, in the third embodiment, a recording test is performed with only one recording speed, and recording parameters for recording speeds that are not recorded are calculated.

  FIG. 9 is a flowchart showing an operation flow of the optical disk recording apparatus according to the third embodiment, and FIG. 10 is a diagram showing a concept of correcting the reference WST function equation.

  The optical disc recording apparatus 100 performs a recording test on the test area at any one recording speed among the recording speeds on the optical disc 10 (step S21).

  Subsequently, the optical disc recording apparatus 100 determines an optimum recording parameter (WST, recording power) at an arbitrary one-step recording speed based on the result of the recording test (step S22).

  The optical disc recording apparatus 100 compares the determined recording parameters (WST, recording power) with the recording parameters in the reference function formulas (base WST relational expression, base recording power relational expression) for the recording speed at which the recording test was performed. The reference relational expression is corrected in parallel so that the two match (step S23). That is, as shown in FIG. 10, the reference relational expression is translated so that the large white circle overlaps the large black circle. By doing so, the white circle with a small base strategy and base recording power moves to the position of a white triangle with a small post-correction strategy and post-correction recording power.

  The optical disc recording apparatus 100 substitutes the recording speed not subjected to the recording test into the parallel corrected reference relational expression, and calculates the optimum WST for each (Step S15). The optimum recording parameters for the recording speed at which the recording test is not executed can be found from the coordinates of the white triangle in FIG.

  As described above, in the third embodiment, a recording test is performed at only one recording speed, and the result is reflected in the reference function equation. Therefore, an appropriate recording parameter can be calculated with a smaller calculation amount and calculation time.

  In FIG. 10, the recording test is executed at the recording speed Vmin, and the result is reflected in the reference function formula. However, the present invention is not limited to this. The recording test may be executed at any other recording speed such as the recording speed Vmax and used to correct the reference function equation.

(Fourth embodiment)
In the fourth embodiment, when test recording is performed at a plurality of recording speeds in the first embodiment, the recording quality of the test recording is evaluated.

  In the fourth embodiment, the WST calculation unit 118 serves as a quality inspection unit, and the control unit 130 serves as a maximum recording speed determination unit.

  FIG. 11 is a flowchart showing an operation flow of the optical disc recording apparatus according to the fourth embodiment.

  First, it is defined that the variable x is 1 to max (step S31). Here, max is an arbitrary integer and is the number of recording speed stages for test recording. For example, in the example of the first embodiment, max = 4 because test recording is performed at four recording speeds V1 to V4.

  The optical disc recording apparatus 100 executes a recording test at the recording speed V1 (step S32). The optical disc recording apparatus 100 determines whether or not the recording quality satisfies a predetermined condition (step S33). Whether or not the predetermined condition is satisfied includes, for example, a deviation based on a sample number ratio of various signals processed in the data discrimination / calculation unit 112, a deviation amount (deviation) from the theoretical center value of each signal distribution, and a time difference jitter (Data). -Clock jitter), a correlation function based on a mark edge change amount, and an influence of adjacent edges due to a thermal interference effect.

  If the recording quality does not satisfy the predetermined condition (step S33: NO), the recording test is not executed at a recording speed lower than this, so the quality cannot be guaranteed. Therefore, the optical disc recording apparatus 100 notifies the user as a recording error (step S34).

  When the recording quality satisfies the predetermined condition (step S33: YES), the optical disc recording apparatus 100 increments the variable x by 1 (step S35). Subsequently, the optical disc recording apparatus 100 executes a recording test at the recording speed Vx (V2 when executed first) (step S36).

  Further, the optical disc recording apparatus 100 determines whether or not the recording quality satisfies a predetermined condition for the current recording test (step S37). If the recording quality does not satisfy the predetermined condition (step S37: NO), the optical disc recording apparatus 100 cannot guarantee the recording quality at the recording speed or higher, so the recording speed V (x-1) is set to the maximum recording speed ( Step S38).

  When the recording quality satisfies the predetermined condition (step S37: YES), the optical disc recording apparatus 100 determines whether the variable x = max, that is, x = 4 in the example of the present embodiment (step S39). If the variable x is not max (step S39: NO), the process returns to step S35 and increments the variable x. On the other hand, if the variable x = max (step S39: YES), the optical disc recording apparatus 100 does not perform the recording test at a recording speed higher than this, so the current recording speed Vx (V4) is set to the maximum recording speed. (Step S40).

  As described above, in the fourth embodiment, the recording quality is also evaluated during the writing test, and the recording speed at which the predetermined quality is guaranteed is set to the maximum recording speed. Therefore, stable quality can be obtained at the maximum recording speed. It is done.

(Fifth embodiment)
In the first embodiment, the recording parameters are adjusted before recording in the data area. In the fifth embodiment, the recording parameters are adjusted during recording in the data area on the premise that the recording parameters are calculated by performing test recording at a plurality of recording speeds in the first embodiment.

  In the fifth embodiment, the WST calculation unit 118 also serves as a parameter adjustment unit and a function formula correction unit.

  FIG. 12 is a flowchart showing the flow of the operation of the optical disk recording apparatus according to the fifth embodiment, and FIG. 13 is a diagram showing the concept of adjusting the recording parameters during recording in the data area.

  In the method of the first embodiment, it is assumed that a recording test is executed for recording speeds V1 to V4, and WST1 to WST4 are calculated as optimum recording parameters, respectively. In addition, it is assumed that the WST for the recording speeds Va, Vb, and Vc is further calculated between the recording speeds V1 and V2, and the recording speed Vz is set between Va and Vb as the WST review speed. It shall be. Note that the recording review speed (Vz) does not necessarily coincide with the recording speed change (Va, Vb...).

  The optical disc recording apparatus 100 determines whether or not the current recording speed is the WST review speed Vz during recording (step S41) (step S42). If the recording speed is not the WST review speed (step S42: NO), the recording is continued as it is. When the recording speed is the WST review speed (step S42: YES), the recording is temporarily stopped (step S43).

  Subsequently, the optical disc recording apparatus 100 reproduces the last recorded portion and evaluates the last recorded result in the data area (step S44).

  The optical disc recording apparatus 100 corrects the recording parameter according to the evaluation of the recording result (step S45). That is, like the recording speed Vz in FIG. 13, the recording parameter (WST / recording power) indicated by a small white circle is adjusted to the recording parameter indicated by a small black circle below.

  Subsequently, the optical disc recording apparatus 100 connects the coordinates of (recording speed, recording parameter) indicated by small black circles with the coordinates of (recording speed V2, recording parameter WST2) already determined in the first embodiment, and functions. The equation (dotted line) is corrected, and the WST switching speeds Vb and Vc between Vz and V2 are corrected (step S47).

  As described above, in the fifth embodiment, the recording parameters are adjusted even during recording in the data area, and the function formula is corrected based on the adjusted parameters. The recording parameters can be corrected during recording even when the is not uniform. Therefore, even if there are few recording tests, higher recording quality can be obtained.

(Sixth embodiment)
In the first embodiment, the recording test is performed at recording speeds at a plurality of stages, not all the stages. The recording test is not necessarily performed at the highest recording speed. In the sixth embodiment, after determining the recording parameters according to the first embodiment, the recording parameters are adjusted when recording at a higher recording speed.

  FIG. 14 is a diagram showing the concept of setting recording parameters at a recording speed higher than the recording speed at which the recording test was performed.

  For the recording speeds V1 to V4, it is assumed that the recording test has been completed according to the method of the first embodiment.

  The optical disc recording apparatus 100 uses WST4 set in the recording test as WST starting from V4 during recording speed V4 to V5, and temporarily stops recording at the point where the recording speed is switched to V5. Playback immediately before the switching position to obtain a deviation, correct the recording parameter, and calculate WST5. Specifically, the WST calculation unit 118 corrects the WST by using the two-edge method or the three-edge method so that the deviation becomes zero. Recording between V5 and Vmax is performed using the WST5 determined here.

  As described above, when the recording speed is changed, the recording parameter before the switching is corrected based on the recording quality immediately before the switching position to obtain the recording parameter at the next speed. Therefore, even when recording is performed at a high recording speed at which a recording test is not performed, the recording can be performed with appropriate recording parameters.

  In the first to fourth embodiments, the case of a CAV recording type optical disk has been described. However, the recording method is not limited to CAV, and can be applied to other recording methods such as a Z-CLV (Zone CLV) recording method.

10 optical disc,
12 Inside test area,
14 Data area,
16 Outer test area,
100 optical disk recording device,
102 Optical pickup,
104 head amplifier,
106 Binarization circuit,
108 Clock shift measurement unit,
110 measured value storage unit,
112 Data discrimination / calculation unit 112,
114 WST storage unit,
116 base WST storage unit,
118 WST calculation unit,
120 decoder,
122 encoder,
124 recording pulse adjustment unit,
126 laser drive unit,
130 Control unit.

Claims (10)

In an optical disc recording apparatus that records information by forming marks and spaces on an optical disc having test areas for recording tests on the inner circumference and outer circumference,
A recording test unit for executing a recording test at a recording speed of at least one of multi-stage recording speeds in the test area of the optical disc;
A parameter determination unit for determining a recording parameter based on a recording test result by the recording test unit;
A parameter calculation unit that calculates a recording parameter when recording is performed at a recording speed at which the recording test is not performed, with the determined recording parameter as a reference;
An optical disc recording apparatus having
The parameter determination unit determines a recording parameter for each recording speed based on a recording test performed at a recording speed of two or more stages,
The parameter calculation unit calculates a function expression of the recording parameter with respect to the recording speed from the recording parameter determined by the recording parameter and the corresponding recording speed, and sets the recording speed at which the recording test is not performed in the function expression. The optical disk recording apparatus according to claim 1, wherein the recording parameter is calculated by substituting.
A storage unit that stores in advance a reference function formula of a recording parameter with respect to the recording speed;
The parameter calculation unit corrects the reference function formula based on the recording parameter determined by the parameter determination unit and the corresponding recording speed, and sets a recording speed at which no recording test is performed on the corrected reference function formula. The optical disk recording apparatus according to claim 1, wherein the recording parameter is calculated by substituting.
The recording test unit performs a recording test at two recording speeds,
4. The optical disk recording apparatus according to claim 3, wherein the parameter calculation unit proportionally corrects the reference function equation from a set of two sets of determined recording parameters and corresponding recording speeds.
The recording test unit performs a recording test at a single recording speed,
The parameter calculation unit calculates a difference between the determined recording parameter and the recording parameter at the one-step recording speed obtained from the reference function equation, and corrects the entire reference function equation by the difference. The optical disk recording apparatus according to claim 3.
A quality inspection unit for inspecting whether or not the recording quality in the recording test at a recording speed of two or more stages satisfies a predetermined condition;
It is confirmed that the quality satisfies a predetermined condition by the quality inspection unit, and the maximum recording speed determination unit that determines the recording at the earliest recording speed as the maximum recording speed,
The optical disk recording apparatus according to claim 2, further comprising:
A parameter adjusting unit for temporarily stopping recording when changing recording parameters during recording in the data area of the optical disc, and adjusting the recording parameters based on a recording result at a recording speed before the stop;
A function formula correcting unit that corrects the function formula from the recording speed before the stop and the adjusted parameter, the recording speed at which the recording parameter is determined by the parameter determining unit, and the recording parameter;
The optical disk recording apparatus according to claim 2, further comprising:
When performing recording in the data area of the optical disc at a recording speed faster than the maximum recording speed among the recording tests, the parameter calculation unit interrupts recording at a predetermined timing during recording, and immediately before the interruption. 5. The optical disk recording apparatus according to claim 2, wherein a recording parameter at a recording speed after the interruption is calculated based on a deviation of the recorded information.
The optical disc recording apparatus according to claim 1, wherein the recording parameter includes at least one of a write strategy and a writing power.
In a write-once optical disc recording method in which information is recorded by forming marks and spaces on an optical disc having test areas for recording tests on the inner circumference and the outer circumference, respectively, by an optical disc recording apparatus.
Performing a recording test on the test area of the optical disc at an arbitrary recording speed of at least one of multi-stage recording speeds;
Determining recording parameters based on the recording test results;
Calculating a recording parameter when recording is performed at a recording speed at which the recording test is not performed on the basis of the determined recording parameter;
Recording method of write-once optical disc having