JPH07287847A - Using method of power calibration area of draw type optical disk and power calibration method - Google Patents

Abstract

PURPOSE:To form the using method of the power calibratuon area for a DRAW type optical disk capable of obtaining an optimal laser recording power in the OPC once performed by using one partition of a PCA. CONSTITUTION:When OPC is performed in writing information in an optical disk, one partition of the test area of the PCA is divided into a first to third areas ER1-ER3 for every five frames and trial writing is performed once in one area. Consequently, since one partition is used for single OPC and an optimal laser recording power and a pulse correction value most suitable for recording are obtained, even when a CD in which 99 pieces of music are recorded is manufactured, plural partitions are not used for performing the single OPC and the CD after a standard is manufactured.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of using a power calibration area for optimizing a recording laser power when recording information on a write-once optical disc.

[0002]

2. Description of the Related Art Conventionally, a write-once optical disc (CD-WO) has been used.
When recording information on the recording laser power optimization (OP
C: Optimun Power Control, hereinafter referred to as OPC). The OPC records predetermined information in a power calibration area (PCA: Power Calibration Area, hereinafter referred to as PCA) of the optical disc, and
This is done by reproducing the recorded information. P
The CA is divided into a test area and a count area, and each is divided into 100 partitions.

One partition in the test area is composed of 15 frames, and one partition is used in one trial writing. As an example of use, the Orange Book, which is the standard for write-once optical discs, was used for trial writing with 15 stages of laser power for 15 frames, and the laser power with the best recording condition was selected. The method of recording information is described.

[0004]

According to the above-mentioned method, when the optimum laser power cannot be found by one trial writing when OPC is performed, or when more appropriate laser power is desired to be obtained. For one OPC
Therefore, it becomes necessary to perform trial writing on a plurality of partitions in the PCA. However, according to the above-mentioned standard, the write-once optical disc can record up to 99 songs, so that the OPC must be performed up to 99 times to record the songs, which requires 99 partitions. . Further, in order to complete a compact disc (hereinafter referred to as a CD), it is necessary to record in the lead-in area and the lead-out area of the optical disc, and therefore, the remaining one partition is used as the OPC.

Therefore, since a maximum of 100 partitions are used to make a CD having 99 songs recorded, if a plurality of partitions are used in one OPC, 99 songs can be recorded. You will not be able to do it, and it will be against the standard.

In view of the above problems, an object of the present invention is a PC
An object of the present invention is to provide a method of using a power calibration area of a write-once optical disc that can obtain an optimum recording laser power in OPC performed using one partition A.

[0007]

In order to achieve the above object, the present invention, in claim 1, defines a plurality of frames as one partition, and irradiates a laser beam to a power calibration area composed of the plurality of partitions for trial. A method of using a power calibration area of a write-once optical disc for performing writing and reading the written information to obtain an optimum power of the laser beam, comprising:
We propose a method of using a power calibration area of a write-once optical disc in which a partition is divided into a plurality of areas and one trial writing is performed in one of the divided areas.

According to a second aspect of the present invention, there is provided a power calibration method for a write-once optical disc in which information is recorded by an EFM signal composed of a pulse signal having a time width that is 3 to 11 times the reference time width. 1 partition in the power calibration area is divided into a plurality of parts, and the time width of the pulse signal is corrected by the first time width correction value in the first divided area of the 1 partition into at least 2
The first power calibration is performed by two laser light powers to obtain the first optimum power, and in the second divided area of the one partition divided into the plurality,
After the test information is written by the first optimum power, the write information in the second divided area is reproduced to detect the variation amount in the time width of a predetermined multiple of the reference time width, and the change A second time width correction value is obtained based on the amount, the time width of the pulse signal is corrected by the second time width correction value, and a second power calibration is performed by at least two laser light powers. A power calibration method for a write-once optical disc is proposed, in which the optimum power of 2 is obtained and the second optimum power and the second time width correction value are used for information recording.

According to a third aspect of the present invention, there is provided a power calibration method for a write-once optical disc in which information is recorded by an EFM signal composed of a pulse signal having a time width which is 3 to 11 times the reference time width. 1 partition in the power calibration area is divided into a plurality of parts, and the time width of the pulse signal is corrected by the first time width correction value in the first divided area of the 1 partition into at least 2
The first power calibration is performed by two laser light powers to obtain the first optimum power, and in the second divided area of the one partition divided into the plurality,
After the test information is written by the first optimum power, the write information in the second divided area is reproduced to detect the variation amount in the time width of a predetermined multiple of the reference time width, and the change A second time width correction value is obtained based on the amount, the time width of the pulse signal is corrected by the second time width correction value, and the first partition of the plurality of partitions is divided by at least two laser light powers. The second power calibration is performed using the area No. 3 to obtain the second optimum power, and the test information is written by the second optimum power in the fourth divided area of one partition divided into the plurality of pieces. After that, the write information to the fourth divided area is reproduced to detect the variation amount in the time width of a predetermined multiple of the reference time width, and the third time width is detected based on the variation amount. A positive value is obtained, the time width of the pulse signal is corrected by the third time width correction value, and the third time is obtained by using at least two laser light powers and a fifth region of one partition divided into the plurality. Power calibration to obtain the third optimum power,
We propose a power calibration method for a write-once optical disc that uses the third optimum power and the third time width correction value for information recording.

According to a fourth aspect of the present invention, in the power calibration method for the write-once optical disc in which information is recorded by an EFM signal composed of a pulse signal having a time width that is 3 to 11 times the reference time width, the write-once optical disk. 1 partition in the power calibration area is divided into a plurality of parts, and the time width of the pulse signal is corrected by the first time width correction value in the first divided area of the 1 partition into at least 2
The first power calibration is performed by two laser light powers to obtain the first optimum power, and in the second divided area of the one partition divided into the plurality,
After writing the test information with the first optimum power, the write information in the second divided area is reproduced to detect the first variation amount in the time width of a predetermined multiple of the reference time width. After that, in the third divided region of one partition divided into the plurality of parts, the time width of the pulse signal is corrected by the second time width correction value, and the second power calibration is performed by at least two laser light powers. Then, the second optimum power is obtained, and the test information is written by the second optimum power in the fourth divided area of the one partition divided into the plurality of pieces, and then the write information to the fourth divided area is obtained. Play
A second variation amount in a time width of a predetermined multiple of the reference time width is detected, and the reference time width of the reference time width is determined based on the first and second time width correction values and the first and second fluctuation amounts. A third time width correction value at which the amount of fluctuation in the time width of a predetermined multiple becomes 0 is obtained, the time width of the pulse signal is corrected by the third time width correction value, and a third time width correction value is obtained using at least two laser light powers. A power calibration method for a write-once optical disc is proposed, in which a third power calibration is performed to obtain a third optimum power, and the third optimum power and the third time width correction value are used for information recording.

Further, in claim 5, claim 2, 3 or 4 is provided.
In the power calibration method for the write-once optical disc described above, when the fluctuation amount is detected, the reference time width of 3 is set.
We propose a power calibration method for write-once optical disks that detects the amount of fluctuation in double time width.

[0012]

According to the first aspect of the present invention, one partition is divided into a plurality of areas, and one trial writing is performed in one of the divided areas. Therefore, one trial writing is optimal. Even if the recording laser power cannot be obtained, trial writing can be performed again in another area in the partition, and one partition can be used in one OPC to obtain the optimum recording laser power. it can.

According to a second aspect, one partition in the power calibration area of the write-once optical disc is divided into a plurality of parts, and the first time width correction is performed in the first divided area of the one partition. The time width of the pulse signal is corrected by the value, and the first power calibration is performed with at least two laser light powers to obtain the first optimum power. Furthermore, after the test information is written by the first optimum power in the second divided area of the one divided into the plurality of pieces, the information written in the second divided area is reproduced and the reference information is reproduced. 3 to 1 times the time width
A fluctuation amount in a time width of a predetermined multiple of 1 is detected. Then, a second time width correction value is obtained based on the variation amount, the time width of the pulse signal is corrected by the second time width correction value, and the second power is corrected by at least two laser light powers. Calibration is performed to obtain the second optimum power, and the second optimum power and the second time width correction value are used for information recording.

According to the third aspect, one partition in the power calibration area of the write-once optical disc is divided into a plurality of partitions, and the first time width correction is performed in the first divided area of the one partition. The time width of the information writing pulse signal is corrected by the value, and the first power calibration is performed with at least two laser light powers to obtain the first optimum power. Furthermore, after the test information is written by the first optimum power in the second divided area of the one divided into the plurality of pieces, the information written in the second divided area is reproduced and the reference information is reproduced. Time width 3
The variation amount in the time width of a predetermined multiple of the multiple times to 11 times is detected, and the second time width correction value is obtained based on the variation amount. After that, the time width of the pulse signal is corrected by the second time width correction value, and the pulse signal is divided into the plurality of 1's.
The second optimum power is obtained by performing the second power calibration by using at least two laser light powers using the third region of the partition. Then, after writing the test information by the second optimum power in the fourth divided area of the one divided into the plurality of pieces, the write information in the fourth divided area is reproduced, and A fluctuation amount in a time width of a predetermined multiple of the reference time width is detected, and a third amount is detected based on the fluctuation amount.
The time width correction value of is obtained. Furthermore, the time width of the pulse signal is corrected by the third time width correction value, and the third time power calibration is performed by using the fifth region of one partition divided into the plurality by the at least two laser light powers. Is performed to determine the third optimum power, and the third optimum power and the third time width correction value are used for information recording.

According to a fourth aspect, one partition in the power calibration area of the write-once optical disc is divided into a plurality of parts, and the first time width correction is performed in the first divided area of the one partition. The time width of the pulse signal for writing information is corrected by the value, and the first power calibration is performed with at least two laser light powers to obtain the first optimum power. Furthermore, after the test information is written by the first optimum power in the second divided area of the one partition divided into the plurality of pieces, the write information in the second divided area is reproduced, and After the first variation amount in the time width of a predetermined multiple of the reference time widths 3 to 11 times is detected, the second time width correction value is set in the third divided area of the one partition divided into the plurality of times. Thus, the time width of the pulse signal is corrected, and the second optimum power is obtained by performing the second power calibration with at least two laser light powers. Then, after writing the test information by the second optimum power in the fourth divided area of the one divided into the plurality of pieces, the write information in the fourth divided area is reproduced, and The second variation amount in the time width of a predetermined multiple of the reference time width is detected. Thereafter, a third time width in which a fluctuation amount in a time width of a predetermined multiple of the reference time width becomes 0 based on the first and second time width correction values and the first and second fluctuation amounts. A correction value is obtained, the time width of the pulse signal is corrected by the third time width correction value, and the fifth of one partition is divided into a plurality of parts by at least two laser light powers.
The third power calibration is performed by using the area of 3 to obtain the third optimum power, and the third optimum power and the third time width correction value are used for information recording.

According to a fifth aspect of the present invention, when the fluctuation amount is detected, the fluctuation is most prominent when the fluctuation is 3 times the reference time width.
The fluctuation amount in the double time width is detected.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. As shown in FIG. 1, the PCA is divided into 100 partitions P001 to P100, and each partition P001
001 to P100 are composed of 15 frames F01 to F15.

When obtaining the optimum recording laser power, P
When trial writing is performed on the CA, in the first embodiment, one partition is divided into first to third areas ER1 of 5 frames each.
~ Divide into ER3 and perform trial writing three times.

As write information for trial writing, a well-known EFM (Eight to Fourteen Modu) consisting of a pulse train having a time width 3 to 11 times the reference time width T is used.
lation) signal and the EFM signal is used to modulate the laser power for trial writing.

FIG. 2 is a schematic block diagram showing an optical disk recording / reproducing apparatus according to the present invention. In the figure, reference numeral 1 denotes an encoder, which converts information to be written into an EFM signal and outputs it. A recording control circuit 2 inputs an EFM signal and a control signal from a CPU described later, and outputs a drive control signal to the servo circuit 3 and the laser drive circuit 4. The servo circuit 3 sets the position of the optical pickup 5 and the position of the objective lens (not shown) to proper positions. The laser drive circuit 4 energizes a laser diode (not shown) in the optical pickup 5 based on the drive control signal input from the recording control circuit 2, and causes the laser diode to emit laser light to the optical disc 6.

Reference numeral 7 denotes an RF amplifier circuit, which inputs an RF signal corresponding to the reflected light from the optical disc 6 received by the optical pickup 5, amplifies the RF signal, and supplies it to the jitter detection circuit 8 and the β detection circuit 9. Output. Jitter detection circuit 8
Generates an EFM signal by binarizing the input RF signal, measures the time width of a pulse having a time width three times the reference time width T (hereinafter, referred to as 3T time width), and measures each measured time width. The time width data is output to the CPU 10. The β detection circuit 9 receives the peak value of the input RF signal, that is, the maximum value A
And the minimum value B are measured, and the β value calculated by the following equation (1) is output to the CPU 10.

Β = (A + B) / (A−B) (1) The CPU 10 collects statistics of the 3T time width data input from the jitter detection circuit 8 and based on the statistical result, the time width of the writing EFM signal. The correction value is calculated, the optimum laser power is obtained based on the β value, and these data and a control signal for instructing the correction based on these data are output to the recording control circuit 2.

Next, the operation of the first embodiment having the above construction will be described in detail with reference to the flow chart shown in FIG. At the start of writing information to the optical disc, OPC is performed. CPU10 when performing OPC
Sets the time width correction value of the writing EFM signal and the laser power to initial values (SA1). After that, the PCA test area is searched (SA2), and one partition to be used is divided into first to third areas ER1 to ER3 of 5 frames as shown in FIG. 1 (SA3).

Next, the CPU 10 writes with the first laser power in the first frame of the first area ER1 (SA4). The laser power at this time is the minimum value of the five types of laser power corresponding to the five types of voltages obtained by dividing the minimum value and the maximum value of the voltage applied to the laser diode into five. After that, the laser power is set to different values in the second frame to the fifth frame of the first area ER1 and writing is performed (SA5 to SA
8).

After writing in all the frames in the first area ER1, the written information is reproduced (SA
9) Find the β value in each frame (SA10).
Based on these five β values, as shown in FIG. 4, the β values are interpolated to obtain the laser power at which β = a (the best value), that is, the voltage Vb applied to the laser diode (SA1
1).

Next, the CPU 10 instructs the recording control circuit 2 to set the laser power at which β = a, and writes to the second area ER2 by this laser power (SA12).
After that, the information written in the second area ER2 is reproduced (SA13), and one of the 5 frames, for example, 4
The jitter data at the frame, that is, the time width of a plurality of 3T pits is read (SA14).

Next, the average value of the time width of the read 3T pits is calculated (SA15). Here, as shown in FIG. 5, ± 118 ns is equally divided into four with the accurate 3T time width as the center, and the number of 3T pits included in each of these four regions is set to the number N _{1 to} N ₄ of each region. center value t ₁ ~t ₄ calculates the sum of the multiplied value by the average value t _m division to the time width by the number of all the 3T pit included this value into four regions of
Are seeking. These are expressed by the following formula (2).

T _m = (t ₁ N ₁ + t ₂ N ₂ + t ₃ N ₃ + t ₄ N ₄ ) / (N ₁ + N ₂ + N ₃ + N ₄ ) ... (2) Due to the above, the initial correction amount in the time width is x ′. It was possible to find the deviation y'of the time width at the time. Further, it has been found from a preliminary experiment that the relationship between the correction amount x of the time width and the deviation y of the time width is expressed by a straight line having a constant inclination k in various optical disks. Therefore, as shown in FIG. 6, an optimum 3T value is obtained by obtaining an x value (correction value) when a straight line passing through (x ', y') with an inclination of k intersects with y = 0.
It is possible to obtain a correction value x of a time width capable of forming pits, that is, minimizing jitter (SA1
6).

The CPU 10 instructs the recording control circuit 2 to the value of the correction value x thus obtained, and the time width of the recording EFM signal is corrected (SA17).

Next, the CPU 10 writes with the first laser power in the first frame of the third area ER3 (SA18). The laser power at this time is the minimum value of the five types of laser power corresponding to the five types of voltages obtained by dividing the minimum value and the maximum value of the voltage applied to the laser diode into five, as described above. It After that, the laser power is set to different values in the second frame to the fifth frame of the third region ER3 and writing is performed (SA19 to SA22).

After writing in all the frames in the third area ER3, the written information is reproduced (SA
23), the β value in each frame is calculated (SA2
4). Based on these five β-values, the β-values are interpolated in the same manner as described above to obtain the laser power at which β = a (best value) (SA25), and the OPC is ended.

Next, the CPU 10 instructs the optimum laser power obtained by OPC to the recording control circuit 2 and writes information by this laser power (SA2).
6).

As described above, according to the first embodiment, P
When performing test writing on CA, one partition is divided into first to third regions ER1 to ER3 of 5 frames each, and test writing is performed three times to obtain the optimum recording laser power. 1 using one partition
The optimum recording laser power can be obtained in one OPC.

In the first embodiment, one partition in the PCA test area is divided into three areas ER1 to E.
Although the test writing was performed once in each of the regions ER1 to ER3 by dividing the region into R3, the present invention is not limited to this. The purpose of the present invention is to divide one partition into a plurality of areas, perform one trial writing in each area, and obtain the optimum recording laser power. The number of partitions is almost the same. The effect of is obtained.

Next, a second embodiment of the present invention will be described.
Also in the second embodiment, the optical disk recording / reproducing apparatus having the configuration shown in FIG. 2 is used. Further, the difference from the first embodiment is that in the second embodiment, as shown in FIG. 7, one partition in PCA has five areas ER.
It is divided into a to ERe and trial writing is performed 5 times. Here, the first area ERa is 5 frames, and the second area ER
b is 2 frames, the third region ERc is 3 frames, 4th
The area ERd is composed of 2 frames, and the fifth area ERe is composed of 3 frames.

Next, the power calibration method in the second embodiment will be described with reference to the flow chart shown in FIG.

When starting the writing of information on the optical disc, when performing OPC, the CPU 10 sets the time width correction value and the laser power of the writing EFM signal to the initial values (SB1). Then, the PCA test area is searched (SB2), and one partition to be used is searched for the first to fifth areas ERa to ERe as shown in FIG.
(SB3).

Next, the CPU 10 writes with the first laser power PW1 in the first frame of the first area ERa (SB4). The laser power PW1 at this time is the minimum value of the five types of laser power corresponding to the five types of voltages obtained by dividing the minimum value and the maximum value of the voltage applied to the laser diode into five. After this, the first area ERa
For the second to fifth frames, the laser power is set to different values PW2 to PW5 and writing is performed (SB5 to SB8).

After writing in all the frames in the first area ERa, the written information is reproduced (SB
9) Find the β value in each frame (SB10).
Based on these five β values, as shown in FIG.
Laser power that interpolates between the values and becomes β = a (best value),
That is, the applied voltage Vb to the laser diode is calculated (SB
11).

Next, the CPU 10 instructs the recording control circuit 2 to set the laser power PW6 for β = a, and the laser power PW6 writes in two frames of the second area ERb (SB12). Then, the information written in the second area ERb is reproduced (SB13), and the jitter data in one frame of the two frames, for example, the second frame, that is, the time width of a plurality of 3T pits is read (SB.
14).

Next, the average value of the time widths of the read 3T pits is obtained as in the first embodiment (SB15).

From the above, the time width deviation y'when the initial correction amount in the time width is x'can be obtained.
In addition, the relationship between the correction amount x of the time width and the deviation y of the time width in various types of optical discs has been determined by a preliminary experiment.
It is known to be represented by a straight line. Therefore, as shown in FIG. 6, a straight line passing through (x ', y') with an inclination of k is
By obtaining the x value (correction value) when y = 0 intersects, it is possible to obtain the correction value x of the time width capable of forming the optimum 3T pit, that is, minimizing the jitter (SB16).

The CPU 10 instructs the recording control circuit 2 the value of the correction value x thus obtained to correct the time width of the recording EFM signal (SB17).

Next, the CPU 10 uses the three laser powers of the laser power PW6 (= PW7) thus obtained and the laser powers PW8 and PW9 (PW7 <PW8 <PW9) which are slightly higher than the laser power PW6 (= PW7). Writing is performed in each frame of the area ERc. That is, 1 of the third region ERc
Writing with the laser power PW7 in the frame (S
B18), and thereafter, for the second frame and the third frame of the third region ERc, laser powers PW8 and PW9
Are sequentially written using (SB19, SB20).

After writing in all the frames of the third area ERc, the written information is reproduced (SB
21), the β value in each frame is calculated (SB2
2). Based on these three β values, the laser power at which β = a (the best value), that is, the voltage Vb applied to the laser diode is obtained by interpolating between the β values in the same manner as described above (SB23).

Next, the CPU 10 instructs the recording control circuit 2 to set the laser power PW10 at which β = a, and the laser power PW10 writes in two frames of the fourth area ERd (SB24). After this, the fourth area ER
The information written in d is reproduced (SB25), the jitter data in one frame of the two frames, for example, the second frame, that is, the time width of a plurality of 3T pits is read (SB26).

Then, the average value of the time width of the read 3T pits is obtained in the same manner as described above (SB27). From the above, it is possible to obtain the deviation y ′ of the time width when the initial correction amount in the time width is x ′. Also, as in the case described above, the amount of time width correction x
It has been found that the relationship between and the time width deviation y is represented by a straight line with a constant slope k. Therefore, as shown in FIG.
By obtaining an x value (correction value) when a straight line having a slope of k and passing through (x ', y') intersects with y = 0, a time width correction value x that can minimize the jitter is obtained. It is possible (SB28).

The CPU 10 gives an instruction to the recording control circuit 2 for the value of the correction value x thus obtained, and the time width of the recording EFM signal is corrected (SB29).

Next, the CPU 10 determines the laser power PW10 (= PW11) obtained above and laser powers PW12 and PW13 slightly higher than this (PW11 <PW12).
Writing is performed in each frame of the fifth region ERe by using the three laser powers of <PW13). That is, writing is performed with the laser power PW11 in the first frame of the fifth area ERe (SB30), and then the third area ERe is written.
Writing is sequentially performed on the second frame and the third frame using the laser powers PW12 and PW13 (S
B31, SB32).

After writing in all the frames of the fifth area ERe, the written information is reproduced (SB
33), the β value in each frame is obtained (SB3
4). Based on these three β values, the laser power that gives β = a (the best value), that is, the voltage Vb applied to the laser diode is obtained by interpolating between the β values in the same manner as described above (SB35), and OPC is performed. To finish.

Next, the CPU 10 instructs the optimum laser power obtained by OPC to the recording control circuit 2 and writes information by this laser power (SB3).
6).

As described above, according to the second embodiment, P
When performing test writing to CA, set 1 partition to 1st
To the fifth area ERa to ERe, the power calibration is performed three times to obtain the optimum recording laser power in a convergent manner, so that it is optimal in one OPC performed using one partition. The recording laser power can be obtained.

Next, a third embodiment of the present invention will be described.
Also in the third embodiment, the optical disk recording / reproducing apparatus having the configuration shown in FIG. 2 is used. Further, the difference from the first embodiment is that in the second embodiment, as shown in FIG. 7, one partition in PCA has five areas ER.
It is divided into a to ERe and trial writing is performed 5 times. Here, the first area ERa is 5 frames, and the second area ER
b is 2 frames, the third region ERc is 3 frames, 4th
The area ERd is composed of 2 frames, and the fifth area ERe is composed of 3 frames.

Next, the power calibration method in the third embodiment will be described with reference to the flow chart shown in FIG.

When starting the writing of information to the optical disc, when performing OPC, the CPU 10 sets the time width correction value and laser power of the writing EFM signal to initial values (SC1). Then, the PCA test area is searched (SC2), and one partition to be used is searched for the first to fifth areas ERa to ERe as shown in FIG.
(SC3).

Next, the CPU 10 sets the time width correction value to x ₁
As a result, writing is performed with the first laser power PW1 in the first frame of the first area ERa (SC4). The laser power PW1 at this time is the minimum value of the five types of laser power corresponding to the five types of voltages obtained by dividing the minimum value and the maximum value of the voltage applied to the laser diode into five. After that, the laser power is set to a different value P for the second to fifth frames of the first region ERa.
W2-PW5 (PW1 <PW2 <PW3 <PW4 <PW
5) is set and writing is performed (SC5 to SC8).

After writing in all the frames of the first area ERa, the written information is reproduced (SC
9) Find the β value in each frame (SC10).
Based on these five β values, as shown in FIG.
Laser power that interpolates between the values and becomes β = a (best value),
That is, the voltage Vb applied to the laser diode is calculated (SC
11).

Next, the CPU 10 instructs the recording control circuit 2 to set the laser power PW6 at which β = a, and the laser power PW6 writes in two frames of the second area ERb (SC12). Thereafter, the information written in the second area ERb is reproduced (SC13), and the jitter data in one frame of the two frames, for example, the second frame, that is, the time width of a plurality of 3T pits is read (SC.
14).

Next, as in the first embodiment, the variation amount of the time width of the read 3T pit, that is, the average value Dev1 of the deviation amount from the standard time width is obtained (SC15).

Next, the CPU 10 sets the time width correction value to x ₂
As above, the obtained laser power PW6 (= PW7) and laser powers PW8 and PW9 slightly higher than this are obtained.
Writing is performed in each frame of the third region ERc by using three laser powers of (PW7 <PW8 <PW9). That is, writing is performed with the laser power PW7 in the first frame of the third area ERc (SC16), and thereafter, the laser powers PW8 and PW9 are used for the second frame and the third frame of the third area ERc. Are sequentially written (SC17, SC18).

After writing in all the frames of the third area ERc, the written information is reproduced (SC
19), find the β value in each frame (SC2
0). Based on these three β values, the laser power that gives β = a (the best value), that is, the voltage Vb applied to the laser diode is obtained by interpolating between the β values in the same manner as described above (SC21).

Next, the CPU 10 instructs the recording control circuit 2 to set the laser power PW10 at which β = a, and the laser power PW10 writes in two frames of the fourth area ERd (SC22). After this, the fourth area ER
The information written in d is reproduced (SC23), the jitter data in one frame of the two frames, for example, the second frame, that is, the time width of a plurality of 3T pits is read (SC24). Then, the variation amount of the time width of the 3T pit read in the same manner as described above, that is, the average value Dev2 of the deviation amount from the standard time width is obtained (SC25).

Next, the above-mentioned correction value x ₂ and average value Dev
As shown in FIG. 10, the correction value x ₃ at which the average value Dev becomes 0 is obtained from the straight line obtained by 2 and the previous correction value x ₁ and the average value Dev 1 (SC26).

The value of the correction value x ₃ obtained here is used by the CPU 10
Then, the recording control circuit 2 is instructed to correct the time width of the recording EFM signal (SC27).

Next, the CPU 10 calculates the laser power PW10 (= PW11) and the laser powers PW12 and PW13 slightly higher than this (PW11 <PW12).
Writing is performed in each frame of the fifth region ERe by using the three laser powers of <PW13). That is, writing is performed with the laser power PW11 in the first frame of the fifth area ERe (SC28), and then the third area ERe is written.
Writing is sequentially performed on the second frame and the third frame using the laser powers PW12 and PW13 (S
C29, SC30).

After writing in all the frames of the fifth area ERe, the written information is reproduced (SC
31), β value in each frame is calculated (SC3
2). Based on these three β values, the laser power that gives β = a (the best value), that is, the voltage Vb applied to the laser diode is obtained by interpolating between the β values in the same manner as described above (SC33), and OPC is performed. To finish.

Next, the CPU 10 instructs the recording control circuit 2 to the optimum laser power obtained by OPC, and the information is written by this laser power (SC3).
4).

As described above, according to the third embodiment, P
When performing test writing to CA, set 1 partition to 1st
Through dividing into the third regions ER1 to ER3 and performing the power calibration three times to obtain the optimum recording laser power, one partition is used.
The optimum recording laser power can be obtained in one OPC.

[0069]

As described above, according to the method of using the power calibration area of the write-once optical disc according to claim 1 of the present invention, one partition is divided into a plurality of areas, and one of the divided areas is divided. Since the trial writing is performed once in one area, even if the optimum recording laser power cannot be obtained by one trial writing, the trial writing can be performed again in another area in the partition. Since one partition can be used in one OPC and the optimum recording laser power can be obtained, even when making a CD with 99 songs recorded, use multiple partitions in one OPC. And a very excellent effect that a CD conforming to the standard can be produced.

Further, according to the power calibration method for the write-once optical disc of the second aspect, one partition is divided into a plurality of areas, and the power calibration is performed twice using the plurality of areas so as to converge. The optimum recording laser light power and time width correction amount can be obtained. Therefore, even when producing a CD in which 99 songs are recorded, it is not necessary to use a plurality of partitions in one OPC, and a CD conforming to the standard can be produced.

According to the power calibration method for the write-once optical disc of the third aspect, one partition is divided into a plurality of regions, and the power calibration is performed three times using the plurality of regions to converge. The optimum recording laser light power and time width correction amount can be obtained. Therefore, even when producing a CD in which 99 songs are recorded, it is not necessary to use a plurality of partitions in one OPC, and a CD conforming to the standard can be produced.

According to the power calibration method of the write-once read-many optical disc according to the fourth aspect, one partition is divided into a plurality of areas, and the power calibration is performed three times using the plurality of areas to converge. The optimum recording laser light power and time width correction amount can be obtained. Therefore, even when producing a CD in which 99 songs are recorded, it is not necessary to use a plurality of partitions in one OPC, and a CD conforming to the standard can be produced.

According to the fifth aspect, in addition to the above-mentioned effect, in the detection of the variation amount when obtaining the time width correction amount, in the time width three times the reference time width in which the variation appears most significantly. Since the fluctuation amount is detected and the time width correction amount is obtained based on the fluctuation amount, the optimum time width correction can be performed.

[Brief description of drawings]

FIG. 1 is a diagram showing a relationship between PCA partitions and frames and an example of partition division according to the first embodiment of the present invention.

FIG. 2 is a schematic configuration diagram showing a recording / reproducing apparatus for an optical disc according to the present invention.

FIG. 3 is a flowchart showing the OPC procedure in the first embodiment of the present invention.

FIG. 4 is a diagram illustrating a method of calculating an optimal β value according to the first embodiment.

FIG. 5 is a diagram illustrating a method of calculating a time width correction value according to the first embodiment.

FIG. 6 is a diagram illustrating a method of calculating a time width correction value according to the first embodiment.

FIG. 7 is a diagram showing a relationship between PCA partitions and frames and an example of partition division according to the second embodiment.

FIG. 8 is a flowchart showing an OPC procedure in the second embodiment.

FIG. 9 is a flowchart showing the OPC procedure in the third embodiment.

FIG. 10 is a diagram illustrating a method of calculating a time width correction value according to the third embodiment.

[Explanation of symbols]

1 ... Encoder, 2 ... Recording control circuit, 3 ... Servo circuit,
4 ... Laser drive circuit, 5 ... Optical pickup, 6 ... Optical disk, 7 ... RF amplification circuit, 8 ... Jitter detection circuit, 9 ... β
Detection circuit, 10 ... CPU.

Claims (5)

[Claims] 1. A plurality of frames are defined as one partition,
Method of using power calibration area of write-once optical disc for irradiating laser light to power calibration area composed of a plurality of partitions for trial writing and reading the written information to obtain optimum power of the laser light A method of using a power calibration area of a write-once optical disc, wherein the one partition is divided into a plurality of areas, and one trial writing is performed in one of the divided areas. 2. A power calibration method for a write-once optical disc, wherein information is recorded by an EFM signal composed of a pulse signal having a time width that is 3 to 11 times the reference time width. 1 is divided into a plurality of partitions, and the time width of the pulse signal is corrected by the first time width correction value in the first divided area of the one partition divided by After the first power calibration is performed to obtain the first optimum power, the test information is written by the first optimum power in the second divided area of the one partition divided into the plurality of second areas. The information written in the divided area of is reproduced by a predetermined multiple of the reference time width. Of the pulse signal, the second time width correction value is obtained based on the fluctuation amount, the time width of the pulse signal is corrected by the second time width correction value, and the second time width correction value is corrected by at least two laser light powers. Two
A power calibration method for a write-once optical disc, comprising: performing a second power calibration to obtain a second optimum power; and using the second optimum power and the second time width correction value for information recording. 3. A power calibration method for a write-once optical disc, wherein information is recorded by an EFM signal composed of a pulse signal having a time width that is 3 to 11 times the reference time width. 1 is divided into a plurality of partitions, and the time width of the pulse signal is corrected by the first time width correction value in the first divided area of the one partition divided by After the first power calibration is performed to obtain the first optimum power, the test information is written by the first optimum power in the second divided area of the one partition divided into the plurality of second areas. The information written in the divided area of is reproduced by a predetermined multiple of the reference time width. Of the pulse signal, the second time width correction value is obtained based on the fluctuation amount, the time width of the pulse signal is corrected by the second time width correction value, and at least two laser light powers are obtained. The second optimum power is obtained by performing the second power calibration using the third area of the one partition divided into the plurality, and the second optimum power is obtained in the fourth divided area of the one partition divided into the plurality of areas. After writing the test information with the optimum power of, the write information to the fourth divided area is reproduced to detect the variation in the time width of a predetermined multiple of the reference time width, and based on the variation. To obtain a third time width correction value, the time width of the pulse signal is corrected by the third time width correction value, and the pulse signal is divided into the plurality of laser light powers by at least two laser light powers. A third power calibration is performed using the fifth area of one partition to obtain a third optimum power, and the third optimum power and the third time width correction value are used for information recording. A power calibration method for a write-once optical disc. 4. A power calibration method for a write-once optical disc, wherein information is recorded by an EFM signal composed of a pulse signal having a time width that is 3 to 11 times the reference time width. 1 is divided into a plurality of partitions, and the time width of the pulse signal is corrected by the first time width correction value in the first divided area of the one partition divided by After the first power calibration is performed to obtain the first optimum power, the test information is written by the first optimum power in the second divided area of the one partition divided into the plurality of second areas. The information written in the divided area of is reproduced by a predetermined multiple of the reference time width. In the third divided area of one partition divided into a plurality of parts, the time width of the pulse signal is corrected by a second time width correction value, and at least two laser light powers are detected. After the second power calibration is performed to obtain the second optimum power, the test information is written by the second optimum power in the fourth divided area of the one partition divided into The write information to the fourth divided area is reproduced to detect the second variation amount in the time width of a predetermined multiple of the reference time width, and the first and second time width correction values and the first and second time width correction values. A third time width correction value at which the amount of change in the time width of a predetermined multiple of the reference time width becomes 0 is obtained based on the second time fluctuation amount, and the third time width correction value is used to determine the parameter. By at least two laser beam power by correcting the time width of the scan signal third
A power calibration method for a write-once optical disc, wherein a third power calibration is performed to obtain a third optimum power, and the third optimum power and the third time width correction value are used for information recording. 5. The power calibration method for a write-once optical disc according to claim 2, 3 or 4, wherein a fluctuation amount in a time width three times the reference time width is detected when the fluctuation amount is detected.