JP2007042261A - Device and method for optimizing recording pulse, and computer program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To decide an optimal recording pulse for each mark and space by shortening switching timing of each test write pulse to the limited test writing area of a disk-like recording medium, and writing various kinds of test write pulses as many as possible. <P>SOLUTION: Test write data are generated (S4), a recording pulse condition M is set to a temporary register 33a (S5), when a unique pattern indicating the break of the recording pulse condition M is detected (S6), the data of the temporary register 33a are written to a recording pulse setting register 33b (S7), test writing is executed (S8), and the steps S5 to S8 are repeated until N=M (M, N=the number of recording pulse setting) is attained (S9 and S10), wherein M=M+1. The test writing is finished at N=M and when a test write flag is turned OFF (S11) (S12), recording signals of the conditions M to N obtained by the test writing are reproduced (S13), optimal value selection is executed (S14), and an optimal recording pulse is decided (S15). <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention writes a mark and a space to each test write area of a disc-shaped recording medium by each of a plurality of types of test write pulses, reads the mark and space written in the test write area, and forms the mark and space. The present invention relates to a recording pulse optimizing apparatus, a recording pulse optimizing method, and a computer program for determining an optimum recording pulse for performing the above.

  Conventionally, data-rewritable disc-shaped recording media include CD-R, CD-RW, DVD-R, DVD-RW, DVD-RAM, MD, MO, and more recently, larger capacity BD- RE (Blu-ray Disc Rewritable) has been developed and is generally sold. In order to realize a high density of the disk-shaped recording medium, the BD-RE has a shorter numerical aperture of the lens in order to shorten the laser wavelength than the DVD and to collect the light beam from a light source such as a laser in a smaller spot. Is increased. However, when the numerical aperture of the lens increases, coma aberration is likely to occur with respect to the warp and tilt of the disk-shaped recording medium. In this case, it is advantageous that the thickness of the cover layer on the reading surface of the disk-shaped recording medium is smaller in that the occurrence of coma aberration can be reduced.

  The transparent substrate that protects the reading surface (recording surface) of the disc-shaped recording medium is 0.6 mm for DVD, but BD-RE has a thinner cover thickness of 0.1 mm, not a transparent substrate. The transmission layer is formed by bonding the transmission sheet to the substrate with an adhesive or by spin coating of resin. In this case, the influence of the thickness error of the transmission sheet and the adhesive, or the thickness error of the transmission layer due to spin coating is much greater than that of DVD, and the recording power unevenness is the laser power during recording. This also affects the recording pulse width.

  The disc-shaped recording medium stores in advance recording condition setting information such as a laser power value required for recording and a recording pulse width. However, the recording management information (recording conditions) stored in the disc-shaped recording medium is formed on the substrate as ROM information, and then the recording medium is stacked on the disc. The characteristics vary.

  That is, even when information is recorded with the same laser power and the same recording pulse width, the size of the recorded mark / space varies depending on the structure of the disc-shaped recording medium, the composition of the recording medium, the ambient temperature, and the like. In particular, in high-density optical recording in which mark edge recording is often performed to provide information at the edge of the mark / space, the change in the recorded mark / space length causes jitter of the reproduced signal and the reproduced data The error rate will be worsened. For this reason, in general, in recording / reproduction of a disk-shaped recording medium, trial writing to the disk-shaped recording medium (test write) is performed, the recording state obtained from the reproduced signal is determined, and the recording condition is corrected as necessary. And is optimizing.

As for the correction of the recording condition, for example, there is a technique described in Patent Document 1 below as a conventional technique for optimizing a recording pulse parameter. According to the technique described in Patent Document 1, test recording is performed in a certain area of each zone on an optical disk divided into a plurality of zones. Also, in Patent Document 2 below, test writing is performed by changing the setting for each sector.
JP 2000-36115 A (paragraph 0009) JP-A-6-36377 (paragraph 0025)

  However, the technique disclosed in Patent Document 1 cannot be applied to an optical disc that is not zone-divided because test recording is performed in a certain area of each zone in an optical disc that is divided into a plurality of zones. In the technique disclosed in Patent Document 2, since the setting is changed in units of sectors and trial writing is performed, it can be applied to an optical disk that is not divided into zones. In particular, when trial writing is performed on a write-once optical disk, A limit is added depending on the number of sectors in the test writing area. By the way, when trial writing is performed, it is desirable to write each mark and space with as many kinds of trial writing pulses as possible for each mark length and space length (for example, 2T, 3T˜). The trial writing area of the medium is limited.

  The present invention has been made to solve such a problem. For a limited trial writing area of a disc-shaped recording medium, the switching timing of each trial writing pulse is advanced so that as many kinds of trial writing pulses as possible. In other words, the optimum recording pulse can be determined for each mark regardless of the influence caused by external factors such as variations in characteristics of the disk-shaped recording medium and the optical recording / reproducing apparatus and temperature. Another object of the present invention is to provide a recording pulse optimizing device, a recording pulse optimizing method, and a computer program that can improve the reproduction signal quality by writing information satisfactorily.

In order to achieve the above object, the present invention writes a mark and a space with each of a plurality of types of test write pulses in a test write area of a disc-shaped recording medium, and the mark and space written in the test write area. In a recording pulse optimizing device for determining an optimal recording pulse for forming the mark and space by reading
A first register for storing test write data for generating a next test write pulse from a current test write pulse of the plurality of types of test write pulses;
A second register for storing test write data for generating a current test write pulse of the plurality of types of test write pulses;
Trial writing data for generating the next trial writing pulse is written to the first register, and the trial writing data written to the second register is read to generate the trial writing pulse of the current time. Means for writing, and then transferring the test write data written in the first register to the second register and repeating the test write for each of the plurality of types of test write pulses. And

In order to achieve the above object, the present invention writes a mark and a space with each of a plurality of types of test write pulses in a test write area of a disc-shaped recording medium, and the mark written in the test write area And a recording pulse optimization method for reading a space and determining an optimum recording pulse for forming the mark and the space,
A first register for storing test write data for generating a next test write pulse from the current test write pulse of the plurality of types of test write pulses, and a current test write of the plurality of types of test write pulses. A second register for storing test write data for generating a pulse, and writing the test write data for generating the next test write pulse into the first register, and the second register A first step of reading out the test write data written in the register, generating the test write pulse of this time, and performing the test write;
A second step of transferring the test write data written in the first register after the first step to the second register and repeating the test write for each of the plurality of types of test write pulses; It is characterized by having.
In order to achieve the above object, the present invention writes a mark and a space with each of a plurality of types of test write pulses in a test write area of a disc-shaped recording medium, and the mark written in the test write area And a computer program for causing a computer to execute a process of reading a space and determining an optimum recording pulse for forming the mark and the space,
A first register for storing test write data for generating a next test write pulse from the current test write pulse of the plurality of types of test write pulses, and a current test write of the plurality of types of test write pulses. A second register for storing test write data for generating a pulse, and writing the test write data for generating the next test write pulse into the first register, and the second register A first step of reading out the test write data written in the register, generating the test write pulse of this time, and performing the test write;
A second step of transferring the test write data written in the first register after the first step to the second register and repeating the test write for each of the plurality of types of test write pulses; ,
It is characterized by having.

  According to the present invention, the test write data for generating the next test write pulse is written in the first register, and the test write data written in the second register is read to generate the current test write pulse. Test write, and then the test write data written in the first register is transferred to the second register and repeated, so that each test is performed on a limited test write area of the disk-shaped recording medium. It is possible to write as many types of test write pulses as possible by switching the write pulse switching timing. As a result, the characteristics of disk-shaped recording media and optical recording / reproducing devices vary, and the influence due to external factors such as temperature. Regardless, it is possible to determine the optimum recording pulse for each mark and space. It is possible to improve the signal quality.

The best mode for carrying out the present invention will be described below with reference to the drawings.
<First Embodiment>
FIG. 1 is a block diagram showing a first embodiment of an optical recording / reproducing apparatus for realizing a recording pulse optimizing apparatus, a recording pulse optimizing method, and a computer program according to the present invention. FIG. 2 shows a laser emission waveform at the time of recording. FIG. 3 is an explanatory diagram showing an example, FIG. 3 is an explanatory diagram showing the relationship between trial writing data and a unique pattern, FIG. 4 is a flowchart for explaining trial writing processing according to the present invention, and FIG. 5 is an optimum recording pulse according to the present invention. It is a flowchart for demonstrating the write-in process of condition information.

  First, a first embodiment of a recording pulse optimization device, a recording pulse optimization method, and a computer program according to the present invention will be described using the optical recording / reproducing apparatus shown in FIG. Here, “trial writing data” of the present invention refers to “trial writing pulse data”, not “recording data for trial writing”. In the optical recording / reproducing apparatus shown in FIG. 1, a phase change type disc-shaped recording medium 1 capable of repeatedly recording and reproducing information is rotationally driven by a spindle motor 2, and a recording track of the disc-shaped recording medium 1 is optical pick-up 10 (optical By scanning with laser light emitted from the PU, digital data (here, mark length / space length = 2T, 3T-8T) in a predetermined data format is optically recorded and reproduced. Here, an optical recording / reproducing apparatus capable of recording / reproducing the phase change type disk-shaped recording medium 1 will be described as an example, but an optical recording / reproducing apparatus capable of recording / reproducing the magneto-optical disk-shaped recording medium may be used. Realization is possible.

  In the optical pickup 10, laser light from a semiconductor laser 11 that is a laser light source is converted into a parallel light beam by a collimator lens 12, passes through a beam splitter 13, and is applied to a signal recording surface on the disk-shaped recording medium 1 by an objective lens 14. Irradiated to be condensed. The reflected light beam (return laser beam) of the laser beam projected and reflected on the signal recording surface of the disc-shaped recording medium 1 is collected by the objective lens 14 and then reflected by the beam splitter 13 to be cylindrical (condensed). The lens 15 is guided to a photodetector 16 which is a light receiving element.

  The photodetector 16 has a structure in which, for example, the light receiving unit is divided into four parts, and a light detection signal from each of these light receiving units is supplied to the matrix circuit 21 through the preamplifier 20, whereby the sum or difference of these signals is obtained. Is taken out as a so-called RF signal (analog signal), a focus error signal, a tracking error signal, or the like. Here, the photodetector 16 and the preamplifier 20 have been described separately. However, a photodetector with a built-in preamplifier function may be used.

  The focus error signal and the tracking error signal are passed through a phase compensation circuit (not shown), and further via a servo drive circuit (not shown), and each drive coil (not shown) of the biaxial drive device of the objective lens 14. The focus servo and the tracking servo are performed. The RF signal is a sum signal of output signals from the respective light receiving units, and is supplied to an EQ (equalizer) 22.

  The RF signal output from the matrix circuit 21 is shaped by the EQ 22, and the next binarization circuit 23 compares the RF signal shaped by the EQ 22 with a predetermined threshold value and binarizes the threshold value as a boundary. Thereby, the shaped RF signal is converted into a digital signal. A PLL (phase lock loop) 24 synchronizes the digital signal with a reference clock signal.

  Recording management information (including disc information (DI)) stored in advance on the disc-shaped recording medium 1 is reproduced at the time of start-up or immediately before the recording operation, and recorded among the digital signals obtained through the above-mentioned path The power information is demodulated by the recording power information demodulator 25, and the recording pulse information is demodulated by the recording pulse information demodulator 28. The demodulated recording power information is sent to the recording power determination unit 26, and the recording pulse information is sent to the recording pulse determination unit 33.

  Next, the recording power information and the recording pulse information described in the recording management information will be described using the example of the laser emission waveform during recording shown in FIG. In this example, description will be made in a form including information for OPC in addition to the recording power information and recording pulse information of the recording management information stored in advance in the disc-shaped recording medium 1. The following parameters are recorded in the record management information.

As recording power information,
“Recording peak power Pind as an index for obtaining the optimum recording peak power Pwo”,
“Multiplier ρ (Pwo = ρ × Pind)”,
“Modulation degree when recording with the recording power described in the recording peak power Pind”,
“Bias power / recording peak power ratio εbw (Pbwo = Pwo × εbw) for obtaining the optimum recording bias power Pbwo”,
“Cooling power / recording peak power ratio εc (Pco = Pwo × εc) for obtaining optimum recording cooling power Pco”,
“Erasing power 1 / recording peak power ratio εe1 (Pe1 = Pwo × εe1) for obtaining optimum erasing power Pe1”,
“Erase power 2 / recording peak power ratio εe2 (Pe2 = Pwo × εe2) for obtaining optimum erase power Pe2”,
“Target ratio κ (κ = Pw / Pthr) of recording peak power Pw and recording threshold peak power Pthr indicating a point on the modulation degree curve at which OPC is executed”.

As the recording pulse information, the following parameters are recorded.
"Lead pulse width Ttop",
“Start pulse front end position information dTtop”,
“Subsequent pulse width Tmp”,
“Erase pulse front end position information dTe” (in some cases, each mark length is set according to the space length). By combining these, a laser emission waveform with respect to the mark length (and space length) is realized as shown in FIG.

  Next, returning to FIG. 1, the recording power determination unit 26 selects and records the recording power information demodulated by the recording power information demodulation unit 25 or the recording power information stored in the memory 30 obtained via the CPU 29. The power setting value is determined. This output signal is sent to the laser drive circuit 27 and becomes a target value when the semiconductor laser is turned on. The memory 30 is, for example, a nonvolatile memory such as a ROM that stores system operation programs and data, and a volatile memory such as a RAM that temporarily stores information read from the disk-shaped recording medium 1 by the optical pickup 10 and a necessary control program. Memory. The memory 30 also stores test data for test writing, and the test data for test writing is sent to the data converter 31 via the CPU 29.

  The data conversion unit 31 converts the data to be recorded (including test data for trial writing) into a predetermined format that can be recorded on the disk-shaped recording medium 1. Here, in the BD-RE disc-shaped recording medium 1, the data to be recorded is 1-7 pp modulated and always includes 1 to 7 “0” s after “1”. The recording target data is converted so that the inversion from “0” to “1” in the recording target data corresponds to the pulse end of the recording data. Thereby, the pulse width of the recording data corresponds to the recording target data of 2 to 8 bits. When the pulse width per bit of data is set equal to the clock period 1T of the PLL 24, each pulse width in the recording data is 2T to 8T. As for the data actually recorded by the BD-RE, the sync signal including the pulse width 9T is converted in addition to the data to be recorded.

  The test writing data generation unit 32 adds a unique pattern for each desired data length to the test writing test data from the data conversion unit 31 to generate test writing data. This output signal is sent to the recording pulse determination unit 33 and the unique pattern detection unit 34.

  In the case of normal recording, the recording pulse determination unit 33 outputs a pulse output for light modulation based on the recording pulse information from the recording pulse information demodulation unit 28 and the test data for test writing from the data conversion unit 31 to a laser driving circuit. Send to 27. At the time of trial writing, trial writing data is set in the temporary register 33a as recording pulse information for trial writing based on the recording pulse information from the recording pulse information demodulator 28. If there is alternative recording pulse information in the memory 30 of the optical recording / reproducing apparatus, it may be used. The trial writing data generated by the trial writing data generation unit 32 is sent to the unique pattern detection unit 34, and the unique pattern detection signal is sent from the unique pattern detection unit 34 to the recording pulse determination unit 33. Although not shown here, the trial writing data generated by the trial writing data generation unit 32 may be sent to the recording pulse determination unit 33 via the CPU 29.

  FIG. 3 shows the relationship between the trial writing data and the unique pattern. As shown in this figure, the recording pulse determination unit 33 sets the current recording pulse condition M in the temporary register 33a before detecting the unique pattern detection signal, and when the unique pattern detection signal is detected, the data in the temporary register 33a is stored. Rewrite to the register 33b. Next, the next recording pulse condition M + 1 is set in the temporary register 33a. When the unique pattern detection signal is detected, the data in the temporary register 33a is rewritten to the register 33b, and this operation is repeated until the last recording pulse condition N. Then, based on the trial writing data generated by the trial writing data generation unit 32, it is sent to the laser drive circuit 27 as a pulse output for optical modulation at the time of trial writing.

  The output signal of the recording pulse determination unit 33 is sent to the laser drive circuit 27, and the semiconductor laser 11 is pulse-driven by the recording power information from the recording power determination unit 26 and the pulse modulation signal at the time of recording from the recording pulse determination unit 33. Recording can be performed on the disk-shaped recording medium 1.

  The jitter measuring unit 35 reproduces the signal recorded on the disk-shaped recording medium 1 as described above, measures the jitter of the recording signal from the PLL 24 and uses it for test writing, and the measurement result is sent to the CPU 29. It is used to select the optimum value of the recording signal obtained by trial writing.

  In the present embodiment, the temporary register 33a and the unique pattern are used at the time of trial writing, and the recording pulse setting at the time of trial writing is efficiently switched to improve the reproduction signal quality by writing information satisfactorily. The first step according to claims 2 and 3 will be described in detail with reference to the flowchart of FIG.

  First, a trial writing flag is turned on (set) in accordance with a trial writing start command (step S1), the optical pickup 10 is moved to the trial writing area of the disk-shaped recording medium 1 (step S2), a spindle servo system, and a focus servo. Each servo system is driven in the order of the system and the tracking servo system and seeks to a predetermined address (step S3).

  Next, the CPU 29 reads out the test writing data stored in the memory 30, sends the test writing data to the data conversion unit 31, and converts the test writing test data into a predetermined format that can be recorded on the disk-shaped recording medium 1. Then, this data is sent to the trial writing data generation unit 32, a unique pattern is added for each desired data length to the test writing test data converted into a recordable format, and trial writing data is generated. (Step S4).

  Although not shown in this flowchart, the recording pulse condition M (M ≧ 1) is obtained based on the recording pulse information obtained by the recording pulse information demodulating unit 28 by reproducing the above-mentioned DI, and the recording pulse condition M Is set in the temporary register 33a (step S5).

  In response to a command from the CPU 29, test write data, which is an output signal of the test write data generation unit 32, is sent to the unique pattern detection unit 34, and when a unique pattern indicating a delimiter of the recording pulse condition M is detected (step S6), the unique data is detected. A pattern detection signal is sent to the recording pulse determination unit 33. When this signal is sent, the recording pulse condition M is written to the register 33b that is normally used (step S7). Here, the unique pattern detection signal is exchanged without going through the CPU 29, but it may be sent to the recording pulse determining unit 33 through the CPU 29. After writing the recording pulse condition M to the register 33b, test writing is executed (step S8). The recording power setting at this time uses recording power information demodulated from the DI value or uses recording power information obtained by recording power calibration such as OPC.

  In order to change the setting a predetermined number of times (from condition M to condition N, where N ≧ M) during trial writing, it is determined whether the number of setting changes has reached a predetermined number (N = M) (step S9). ). When N> M, the condition M (M = number of recording pulses set) is set to M = M + 1 (step 10), the process returns to step S5, and steps S5 to S10 are repeated until N = M. If N = M in step S9, the trial writing flag is determined during trial writing of condition N (step S11). If on, the test writing is returned (step S8), and off (down). Then, the trial writing is finished (step S12).

  Thereafter, the recording signals from the condition M to the condition N obtained by the trial writing are reproduced (step S13), and the minimum jitter value or an approximate expression of these signals is obtained from these signals. A jitter value is selected (step S14). Then, the recording pulse condition corresponding to the jitter value is determined as the optimum recording pulse (step S15).

  Next, the second step according to claims 2 and 3 will be described. The recording pulse parameters in the laser emission waveform at the time of recording described with reference to FIG. 2 include the leading pulse width Ttop, leading pulse leading end position information dTtop, trailing pulse width Tmp, and erasing pulse leading end position information dTe. In the step, the parameters are optimized for these individual parameters or in combination. Specifically, the optimum recording pulse is obtained by repeating steps S1 to S15 shown in the description of the flowchart of FIG.

  An operation for recording information on the optimum recording pulse condition obtained by the above operation in the recording management information area of the disc-shaped recording medium 1 will be described with reference to the flowchart of FIG. First, information on the optimum recording pulse condition stored in the recording pulse determination unit 33 or the memory 30 is sent to the data conversion unit 31 via the CPU 29, where the data is recorded in a format that can be recorded on the disc-shaped recording medium 1. Is converted (step S21).

  Next, the information on the optimum recording pulse condition converted into a format that can be recorded on the disk-shaped recording medium 1 is sent to the recording pulse determining unit 33, and pulse modulated using the information on the optimum recording pulse condition to perform laser drive circuit 27. As for the recording power, the recording power determining unit 26 determines the recording power using the recording power information demodulated from the disc-shaped recording medium 1 as described above or the recording power information obtained by recording power calibration, and the laser. It is sent to the drive circuit 27. The semiconductor laser 11 is driven via the laser drive circuit 27 to record the optimum recording pulse on the disk-shaped recording medium 1 (step S22). The information on the optimum recording pulse condition recorded here can be used as a recording pulse condition at the time of data recording on the disc-shaped recording medium 1 next time, so that the optimum recording pulse can be obtained without performing trial writing. It becomes possible.

<Second Embodiment>
FIG. 6 is a block diagram showing an optical recording / reproducing apparatus according to the second embodiment. In the first embodiment, the optimum value selection in step S14 in FIG. 4 has been described using jitter. However, in the second embodiment, an error rate is used as an index in the optimum value selection, and FIG. An error rate measurement unit 36 is provided instead of the jitter measurement unit 35. A second embodiment will be described using the optical recording / reproducing apparatus shown in FIG. 6 and the flowchart shown in FIG. Steps S1 to S13 are performed as described above. Thereafter, in the optimum value selection in step S14, the minimum error rate value or an approximate expression of these signals is obtained from the reproduction signal, and the minimum error rate value on the approximate expression is obtained. Select. In step S15, the recording pulse condition corresponding to the selected error rate value is determined as the optimum recording pulse.

<Third Embodiment>
FIG. 7 is a block diagram showing an optical recording / reproducing apparatus according to the third embodiment. In the first embodiment, the optimum value selection in step S14 of FIG. 4 has been described using jitter. However, in the third embodiment, asymmetry is used as an index in the optimum value selection, and in FIG. 7, the jitter of FIG. An asymmetry measurement unit 37 is provided instead of the measurement unit 35. A third embodiment will be described using the optical recording / reproducing apparatus shown in FIG. 7 and the flowchart shown in FIG. Steps S1 to S13 are performed as described above. Thereafter, in the optimum value selection in step S14, a value at which asymmetry is best from the reproduced signal (the balance of the reproduced signal is best), or an approximate expression of these signals. And select the value that gives the best asymmetry on the approximate expression. In step S15, the recording pulse condition corresponding to the selected asymmetry value is determined as the optimum recording pulse.

<Fourth embodiment>
FIG. 8 is a block diagram showing an optical recording / reproducing apparatus according to the fourth embodiment. In the first embodiment, the optimum value selection in step S14 has been described using jitter. In the fourth embodiment, the edge shift amount in each mark / space is used as an index in the optimum value selection. An edge shift amount measuring unit 38 is provided instead of the jitter measuring unit 35 of FIG. The fourth embodiment will be described using the optical recording / reproducing apparatus shown in FIG. 8 and the flowchart shown in FIG. Steps S1 to S13 are performed as described above. Thereafter, in the optimum value selection in step S14, the integrated value of the edge shift amount from the reproduction signal, the minimum value of the average value, or an approximate expression of these signals is obtained. Then, the integrated value or average value of the edge shift amount that is minimum in the approximate expression is selected. In step S15, a recording pulse condition corresponding to the integrated value or average value of the edge shift amount is determined as the optimum recording pulse.

According to the present invention, since the recording pulse setting register 33b and the temporary register 33a capable of temporarily storing the next recording pulse setting data are used, the test writing data is updated each time a unique pattern is detected. It is possible to write as many types of trial writing pulses as possible in the limited trial writing area of the disk-shaped recording medium 1 by switching the switching timing of each trial writing pulse. Regardless of the influence of external factors such as variations in the characteristics of the recording / reproducing device and temperature, the optimum recording pulse can be determined for each mark and space, and the reproduction signal is obtained by writing information well. Quality can be improved.
The computer program of the present invention sequentially executes each step as shown in the flowcharts of FIGS. 4 and 5 in accordance with the program stored in the memory 30. Further, although the recording pulse optimization method and computer program of the present invention have been specifically described by the embodiments, the present invention is not limited to this.

1 is a block diagram showing a first embodiment of an optical recording / reproducing apparatus that realizes a recording pulse optimization device, a recording pulse optimization method, and a computer program according to the present invention. It is explanatory drawing which shows the example of the laser emission waveform at the time of recording. It is explanatory drawing which shows the relationship between trial writing data and a unique pattern. It is a flowchart for demonstrating the trial write process of the recording pulse optimization apparatus and recording pulse optimization method and computer program which concern on this invention. It is a flowchart for demonstrating the write-in process of the optimal recording pulse of the recording pulse optimization apparatus which concerns on this invention, a recording pulse optimization method, and a computer program. It is a block diagram which shows 2nd Embodiment of the optical recording / reproducing apparatus which implement | achieves the recording pulse optimization apparatus, recording pulse optimization method, and computer program which concern on this invention. It is a block diagram which shows 3rd Embodiment of the optical recording / reproducing apparatus which implement | achieves the recording pulse optimization apparatus, recording pulse optimization method, and computer program which concern on this invention. It is a block diagram which shows 4th Embodiment of the optical recording / reproducing apparatus which implement | achieves the recording pulse optimization apparatus, recording pulse optimization method, and computer program which concern on this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Disc-shaped recording medium 2 Spindle motor 10 Optical pick-up 11 Semiconductor laser 12 Collimating lens 13 Beam splitter 14 Objective lens 15 Cylindrical (condensing) lens 16 Photo detector 20 Preamplifier 21 Matrix circuit 22 EQ (Equalizer)
23 Binary circuit 24 PLL (phase lock loop)
25 Recording Power Information Demodulation Unit 26 Recording Power Determination Unit 27 Laser Drive Circuit 28 Recording Pulse Information Demodulation Unit 29 CPU
DESCRIPTION OF SYMBOLS 30 Memory 31 Data conversion part 32 Test writing data generation part 33 Recording pulse determination part 33a Temporary register 33b Register 34 Unique pattern detection part 35 Jitter measurement part 36 Error rate measurement part 37 Asymmetry measurement part 38 Edge shift amount measurement part

Claims (3)

In order to form marks and spaces by writing marks and spaces in the trial writing area of the disc-shaped recording medium by each of a plurality of types of trial writing pulses, and reading the marks and spaces written in the trial writing area. In a recording pulse optimization device for determining the optimum recording pulse of
A first register for storing test write data for generating a next test write pulse from a current test write pulse of the plurality of types of test write pulses;
A second register for storing test write data for generating a current test write pulse of the plurality of types of test write pulses;
Trial writing data for generating the next trial writing pulse is written to the first register, and the trial writing data written to the second register is read to generate the trial writing pulse of the current time. Means for writing, and then transferring the test write data written in the first register to the second register and repeating the test write for each of the plurality of types of test write pulses;
A recording pulse optimization device comprising: In order to form marks and spaces by writing marks and spaces in the trial writing area of the disc-shaped recording medium by each of a plurality of types of trial writing pulses, and reading the marks and spaces written in the trial writing area. In the recording pulse optimization method for determining the optimum recording pulse,
A first register for storing test write data for generating a next test write pulse from the current test write pulse of the plurality of types of test write pulses, and a current test write of the plurality of types of test write pulses. A second register for storing test write data for generating a pulse, and writing the test write data for generating the next test write pulse into the first register, and the second register A first step of reading the test write data written in the register, generating the test write pulse of this time, and performing the test write;
A second step of transferring the test write data written in the first register after the first step to the second register and repeating the test write for each of the plurality of types of test write pulses; ,
A recording pulse optimization method comprising: a recording pulse optimization method comprising: In order to form marks and spaces by writing marks and spaces in the trial writing area of the disc-shaped recording medium by each of a plurality of types of trial writing pulses, and reading the marks and spaces written in the trial writing area. In a computer program for causing a computer to execute processing for determining the optimum recording pulse of
A first register for storing test write data for generating a next test write pulse from the current test write pulse of the plurality of types of test write pulses, and a current test write of the plurality of types of test write pulses. A second register for storing test write data for generating a pulse, and writing the test write data for generating the next test write pulse into the first register, and the second register A first step of reading out the test write data written in the register, generating the test write pulse of this time, and performing the test write;
A second step of transferring the test write data written in the first register after the first step to the second register and repeating the test write for each of the plurality of types of test write pulses; ,
A computer program characterized by comprising.

Images