JPH06231463A - Optical information recording and reproducing device - Google Patents

Abstract

PURPOSE:To rapidly obtain optimum recording power at each optical disk. CONSTITUTION:By a controller 103, plural recording power in one sector are set to a laser control circuit 110 in a test zone, and the amplitude of a laser driving signal 116 is changed according to the recording power and the recording power are changed stepwise in one sector to perform recording. Thereafter, the recording power whose amplitude data measured by a signal amplitude measuring circuit 109 is the maximum is judged as the optimum recording power.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is an optical information recording / reproducing apparatus for recording / reproducing information on / from an optical disk in units of sectors, and in particular, it is possible to obtain an optimum recording power at high speed for each mounted optical disk. The optical information recording / reproducing device.

[0002]

2. Description of the Related Art In recent years, an information recording / reproducing apparatus for handling a large capacity, exchangeable information recording medium has begun to spread. In particular, since the optical disk device performs recording / reproduction by forming minute pits on the optical disk using laser light,
Suitable for large-capacity and exchangeable information recording.

The optical disc is very sensitive to the intensity of the laser beam emitted from the semiconductor laser during the recording operation, and the size of the pit formed on the optical disc changes depending on the intensity of the laser beam. The smaller the pit, the smaller the signal obtained from it, and the larger the pit, the smaller the signal obtained because the boundary with the adjacent pit is not known. The intensity of the laser light that increases the signal amplitude is
It depends on the composition of each optical disc.

Since the optical disk device uses an optical disk which is a replaceable medium, compatibility cannot be guaranteed unless recording is performed with a recording power suitable for the characteristics of each optical disk. Therefore, ISO 10090, which is an international standard for 90-mm magneto-optical discs, is devised so as to be compatible with each optical disc medium. Below, ISO
A description will be given based on 10090. FIG. 9 shows ISO 1
This is the format of the optical disc defined by 0090. In the control track shown in Figure 9,
The recording power suitable for the optical disk is described.
The information about the recording power described here includes the number of revolutions of the optical disc, the recording pulse width, and the recording power. However, since the rotation speed is 1800 rpm and the recording pulse width is limited to several types as essential information, it is only a reference when the optical disk device has different rotation speeds and different recording pulse widths. In the optical disk device that is the actual product, 30
The optical disk is rotated at a rotation speed of 00 rpm or more. The test zone shown in FIG. 9 is provided for such an optical disk device. By performing test writing in this test zone, the optimum recording power is obtained for each optical disk to ensure compatibility. For example, JP-A-3-
As shown in Japanese Patent Publication No. 091124, recording is performed by using different recording power for each track, and the optimum recording power is obtained from the number of errors when these tracks are reproduced.

Now, the laser control method used for the optical disk device has only considered driving the laser within the sector with a constant recording power. The laser control circuit itself can be controlled independently of the sector,
The signal for controlling the laser control circuit is controlled so that the laser output is kept constant for each sector. Examples of the laser control circuit include a semiconductor laser drive circuit disclosed in Japanese Patent Laid-Open No. 1-294235. Furthermore, in recent years, a method has been devised in which the output of a laser is immediately controlled in accordance with a modulation signal given from the outside. For example,
The "high-precision laser control method for an optical disk device" presented by Mr. Taguchi at the 1990 IEICE Spring National Convention C-413 and the 1991 IEICE Spring National Convention C-372 is cited.

[0006]

As described above, in the conventional optical information recording / reproducing apparatus, the trial writing was performed in the test zone provided on the optical disk in order to ensure compatibility, but one recording Since the unit of recording by the power is a track or a sector, it is necessary to perform trial writing in many sectors to obtain the optimum recording power, which causes a problem of spending a lot of time.

In view of the above points, the present invention reduces the number of sectors required for trial writing by changing the recording power in one sector stepwise, and an optical information recording capable of obtaining an optimum recording power at high speed. A playback device is provided.

[0008]

An optical information recording / reproducing apparatus for recording / reproducing data sector by sector using an optical disc, wherein the laser power control unit controls a laser output to a set laser power value, and an optical disc. A signal amplitude measuring means for measuring the signal amplitude reproduced from the optical disc, and a laser power control means for setting different laser power values in one sector in stages, and measuring the signal from the sector by the signal amplitude measuring means. The optical information recording / reproducing apparatus is provided with an optimum recording power calculating means for obtaining the optimum recording power of.

An optical information recording / reproducing apparatus for recording / reproducing data in sector units using an optical disc, wherein laser power control means for responding to control a laser output to a set laser power value, and reproduction from the optical disc. Optimum recording power of the optical disk by setting the signal amplitude measuring means for measuring the signal amplitude and the laser power value which is different stepwise in one sector in the laser power control means and measuring the signal from the sector by the signal amplitude measuring means. The optimum recording power calculation means for calculating the error correction number measurement means for calculating the number of errors in the reproduction data for each sector of the optical disk, and the vicinity value calculated by the optimum recording power calculation means for each sector are set in the laser power control means. The number of errors in the sector is measured by the error correction number measuring means to determine the optimum recording power of the optical disc. An optical information recording and reproducing apparatus having a optimal recording power determination means that.

The optimum recording power calculating means is an optical information recording / reproducing apparatus for determining the lower limit and the upper limit of the laser power set in the laser power control means by referring to the recording power written in advance on the optical disk.

The optimum recording power calculating means is an optical information recording / reproducing apparatus which makes a signal to be recorded on an optical disk a signal including many shortest periods.

[0012]

With the above structure, the optical information recording / reproducing apparatus of the present invention can obtain the optimum recording power for each optical disk at high speed.

Further, since the normal recording operation is confirmed by using the optimum recording power predicted by the reproduction amplitude, the reliability can be improved.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the optical information recording / reproducing apparatus of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing a configuration example of the first embodiment of the present invention. In FIG. 1, 101 is an optical information recording / reproducing apparatus, 102 is an internal bus, 103 is a controller, and 104.
Is a data buffer, 105 is an optical head, 106 is a modulation / demodulation circuit, 107 is an error correction circuit, 108 is a recording gate generation circuit, 109 is a signal amplitude measurement circuit, 110 is a laser control circuit, 111 is a reproduction signal, and 112 is a WTDT original signal. , 113 is a WTDT signal, 114 is a WTGT signal, 1
Reference numeral 15 is a HOLD signal, and 116 is a laser drive signal.
Among these, the constituent elements different from the conventional optical information recording / reproducing apparatus are the controller 103 and the recording gate generating circuit 108.
And the signal amplitude measuring circuit 109. Controller 10
Reference numeral 3 controls the entire optical information recording / reproducing apparatus 101 via an internal bus 102 by a program stored inside. In particular, the part that controls the peripheral circuit in order to obtain the optimum recording power for each optical disk is different from the conventional one, and this will be described later. The recording gate generation circuit 108
Conventionally, the controller 10 outputs the control signal to the laser control circuit 110 only in one sector cycle.
3 is different in that the control signal can be output to one sector in a plurality of cycles. Signal amplitude measuring circuit 1
In accordance with a command from the controller 103, the controller 09 obtains a signal amplitude for a fixed time and reports it to the controller 103. Here, the laser control circuit 110 has a patent publication number 01-
The same one as 294235 is used.

FIG. 2 is a timing chart of stepwise recording control for explaining the operation of changing the recording power stepwise in one sector for recording. The controller 103
It is determined that the sector of the test zone of the optical disc has been reached (ID that indicates the address of the sector on the optical disc.
A decision made) at time T _1a of parts finished reads, while monitoring the time by the internal timer, and sets the recording power P ₁ to the laser control circuit 110 at time T _1a, a recording gate generation circuit 108 at time T _1b to start. The recording gate generating circuit 108 starts the WTGT signal 114 at time T _{1b when} it is activated.
Is changed from 0 to 1 and the HOLD signal 115 is set to 0 at time T _1c.
To 1 In addition, the recording gate generation circuit 108
While the OLD signal 115 is 0, the WTDT signal 113 received from the modulation / demodulation circuit 106 is converted into 1 and the WTDT signal 113 is output. The controller 103 stops the recording gate generation circuit 108 at time T _1d . The recording gate generation circuit causes the WTGT signal 114 and HOLD at time T _1d.
The signal 115 is changed from 1 to 0. Laser control circuit 110
Indicates that the WTGT signal 114 is 1 and the HOLD signal 115 is 0
In the _meantime , that is, in the section from T _1b to T _1c , the laser drive signal 116 is feedback-controlled so that the recording power becomes P ₁ , and HOLD
While the signal 115 is 1, that is, in the section from T _1c to T _1d , the laser drive value corresponding to the recording power P ₁ is held and WTDT
When the signal 113 is 1, the laser drive signal 116 is output to the recording power P _1, and when the WTDT signal 113 is 0, the laser drive signal 116 is output as 0. Controller 10
Similarly, 3 controls the peripheral circuits at time T _2a , _b , _d and time T _3a , _b , _d , and the recording power P ₂ at time T _{2a
In 3a} , the recording power P ₃ is set in the laser control circuit 110. Here, the recording power is P ₁ <P ₂ <P ₃ , and the amplitude of the laser drive signal 116 increases accordingly, and as a result, the recording power can be changed stepwise in one sector for recording.

Here, the WTDT original signal 112 is a signal including many shortest periods recorded on the optical disc. For example, RLL used in ISO 10090
If the modulation method is (2,7), the channel bit (C
The shortest cycle is the cycle in which two 0s are entered between 1 as the hannel bits). In order to obtain the WTDT original signal 112 of this shortest cycle, the function of generating this cycle may be added to the modulation / demodulation circuit 106, or the controller 103 outputs a hexadecimal number 492492 ... In the data buffer 104 as a data string. This data string may be created and given to the modulation / demodulation circuit 106 via the error correction circuit 107. In the latter case, the shortest period can be generated by RLL (2,7) modulation. Because it is hexadecimal 492492 ...
Is a repetition of the bit string 010, and RLL (2,
7) The modulation produces the channel bit string 100100 for the input bit string 010.

FIG. 3 shows the recording power in steps within one sector.
Measuring the signal amplitude while playing back the recorded sector
Of step-by-step amplitude measurement control to explain the action to be taken
It is a long chart. If the time symbol is the same as in Fig. 2,
Those that show the same time based on the end of the ID part of the sector
And The controller 103 gradually increases the recording power.
If it is judged that the changed sector has been reached, the internal
While monitoring the time with the Immer, time T_1cSignal amplitude at
The measurement circuit 109 is started and time T_1dWith signal amplitude measurement circuit
Amplitude data A measured by 109₁Read out. And so on
At time T_2c,_d, Time T_3c,_dSignal amplitude measuring circuit 109
To control. Time T_2cThen amplitude data A ₂But at time T_3d
Then amplitude data A₃Is read. T in a sector_1cOr
Et T_1d, T _2cTo T_2d, T_3cTo T_3dOf the recording power
The size of the recording pit differs depending on the difference. Play this
Playback signal 111 is T_1cTo T_1dRecording pit between
Is small, the amplitude is small and T_3cTo T_3dRecorded between
The pit becomes too large and the amplitude becomes small. Therefore,
Amplitude data A₁<A₂> A₃Becomes Controller 103
Is the largest amplitude data A in this case.₂Is obtained
Recording power P₂Is determined as a candidate for the optimum recording power.

Next, the operation of the optimum recording power determining means for trial writing in the sector of the test zone using the above-mentioned optimum recording power candidates will be described with reference to the flowchart shown in FIG. (401) Let the recording power P ₂ be the initial recording power. (402) The controller 103 sets the recording power in the laser control circuit 110. (403) Recording is performed in the sector of the test zone of the optical disc. (404) The reproduced signal 111 of the sector is the modulation / demodulation circuit 1
It is demodulated by 06, and the error correction circuit 107 obtains the number of errors. (405) The number of errors obtained by the error correction circuit 107 is compared with a predetermined allowable number of errors. If the number of errors> the allowable number of errors, the process branches to (406). If the number of errors ≦ the allowable number of errors, the process branches to (407). (406) The recording power is changed to a nearby value, and the process branches to (402). (407) The current recording power is determined as the optimum power.

The operation of determining the lower and upper limit recording powers in trial writing will be described with reference to the data regarding the recording powers written in the control tracks of the optical disk. FIG. 5 is a flowchart for obtaining the lower limit and the upper limit. Here, it is assumed that the disk rotation speed of this apparatus is 3000 rpm. (501) The controller 103 reads the data of the control track into the data buffer 14. (502) The controller 103 confirms whether or not the recording power P ₃₀₀₀ at the disk rotation speed of 3000 rpm is described in the control track data. If it is described, the process branches to (504). If not, the process branches to (503). (503) 18 listed on the control track
The recording power P ₁₈₀₀ at 00 rpm is multiplied by 1.4 to obtain P ₃₀₀₀ . (504) A value obtained by multiplying P ₃₀₀₀ by 0.6 is set as a lower limit recording power P _low, and a value obtained by multiplying P ₃₀₀₀ by 1.2 is set as an upper limit recording power P _high .

The formula shown in the flow chart of FIG. 5 is an example of an empirical rule, and may be different.

Further, in the above description, the recording power of three steps is used in the sector, but it may be two steps or less or four steps or more. Further, the recording power of three steps may be applied to a plurality of sectors, for example, 10 sectors, with a total of 30 steps of recording power. Further, considering that there are defective sectors in the test zone, the same three-step recording power may be repeatedly test-written in a plurality of sectors, and judgment may be made by averaging the amplitudes. Alternatively, the above combination may be used for the determination.

A second embodiment of the optical information recording / reproducing apparatus of the present invention will be described below with reference to the drawings.
FIG. 6 is a block diagram showing a configuration example of the second embodiment of the present invention. 6, the same components as those in the first embodiment described above are designated by the same reference numerals, and detailed description thereof will be omitted. Figure 6
In the part different from the first embodiment described above,
603 is a controller, 608 is a modulation signal generation circuit, 6
Reference numeral 10 is a laser control circuit, and 613 is a laser modulation signal. The controller 603 controls the entire optical information recording / reproducing apparatus 601 by a program stored inside, and in particular, the part that controls the peripheral circuit to obtain the optimum recording power for each optical disc is different from that of the first embodiment. ,
This will be described later. The modulation signal generation circuit 608 is
The laser control circuit 610 generates a laser modulation signal 613 which serves as a reference for generating the laser drive signal 115. The controller 603 is a modulation signal generator 60.
When the recording power is set to 8, the modulation signal generator 608
Outputs the laser modulated signal 613 by amplifying the WTDT original signal 112 with an amplification factor proportional to the set recording power. As the laser control circuit 610, the circuit announced at the 1991 IEICE Spring Conference C-372 is used. The laser control circuit 610 immediately generates a laser drive signal 115 in proportion to the laser modulation signal 613.

Here, the WTDT original signal 112 is a signal including many shortest periods recorded on the optical disk, as in the first embodiment of the present invention.

FIG. 7 shows one sector in the second embodiment.
The operation of changing the recording power step by step in the
6 is a timing chart of stepwise recording control for performing the recording.
The controller 603 sets the test zone of the optical disc.
Judge that the sector has reached the
Time T at which the ID part containing the ground has been read _1a
And judge the time with an internal timer.
, Time T_1aAnd the recording power P is applied to the modulation signal generator 608.
₁To set. The modulation signal generator 608 is a WTDT source.
Recording power P with signal 112 set₁Amplification proportional to
The laser modulation signal 613 is output after being amplified at a rate. laser
The control circuit 610 is proportional to the laser modulation signal 613.
The laser drive signal 115 is output. Controller 603
Is time T _2aWith recording power P₂Modulation signal generator 60
Set to 8, time T_3aWith recording power P₃Generate modulation signal
The device 608 is set. Hereinafter, the modulation signal generator 608
And the laser control circuit 610 operates in the same manner as described above.
To make. Finally, time T_4aPlay power P_FourThe modulating signal
Set to the generator 608. Here, the recording power P₁<
P₂<P₃Of the laser drive signal 116
Becomes larger, and as a result, gradually increases within one sector
It is possible to record by changing the recording power.

FIG. 8 is a timing chart of stepwise amplitude measurement control for explaining the operation of measuring the signal amplitude while reproducing the recorded sector by changing the recording power stepwise within one sector in the second embodiment. Is. 7 that have the same time symbol as in FIG. 7 indicate the same time with reference to the end of the ID portion of the sector. When the controller 603 determines that it has reached the sector where the recording power is changed stepwise, the signal amplitude measuring circuit 109 is activated at time T _1a while monitoring the time by the internal timer, and the signal is measured at time T _2a . At the same time as reading the amplitude data A ₁ measured by the amplitude measuring circuit 109, the signal amplitude measuring circuit 109 is activated again. Similarly, the amplitudes A ₂ and A ₃ are read at times T _3a and T _4a . The sizes of the recording pits in T _1a to T _2a , T _2a to T _3a , and T _3a to T _4a in the sector differ depending on the recording power. The reproduced signal 111 reproduced from this has a small recording pit between T _1a and T _2a , and therefore has a small amplitude.
_{Between 3a} and T _4a , the recording pit becomes too large and the amplitude becomes small. Thus, the amplitude data A ₁ <A _2> A _3. In this case, the controller 603 determines that the recording power P _{2 from} which the largest amplitude data A ₂ is obtained is the optimum recording power candidate.

Other operations are the same as those in the first embodiment of the present invention described above. From the above, the optical information recording / reproducing apparatus in the first embodiment and the second embodiment of the present invention changes the recording power stepwise within one sector and evaluates from the amplitude to perform trial writing. By reducing the number of required sectors, the optimum recording power can be obtained at high speed. Further, since the normal recording operation is confirmed by using the optimum recording power predicted by the reproduction amplitude, the reliability can be improved.

[0027]

As described above, the optical information recording / reproducing apparatus of the present invention can obtain the optimum recording power for each optical disk at high speed.

Further, since the normal recording operation is confirmed by using the optimum recording power predicted by the reproduction amplitude, the reliability can be improved.

[Brief description of drawings]

FIG. 1 is a configuration block diagram of an optical information recording / reproducing apparatus according to a first embodiment of the present invention.

FIG. 2 is a timing chart of stepwise recording control.

FIG. 3 is a timing chart of stepwise reproduction amplitude measurement control.

FIG. 4 is a flowchart showing the operation of the optimum recording power determination means.

FIG. 5 is a flowchart for determining the lower and upper recording powers of trial writing.

FIG. 6 is a configuration block diagram of an optical information recording / reproducing apparatus according to a second embodiment of the present invention.

FIG. 7 is a timing chart of stepwise recording control.

FIG. 8 is a timing chart of stepwise reproduction amplitude measurement control.

FIG. 9 is an explanatory diagram showing a format of an optical disc conforming to ISO 10090.

[Explanation of symbols]

 101 optical information recording / reproducing apparatus 102 internal bus 103 controller 104 data buffer 105 optical head 106 modulation / demodulation circuit 107 error correction circuit 108 recording gate generation circuit 109 signal amplitude measurement circuit 110 laser control circuit 111 reproduction signal 112 WTDT original signal 113 WTDT signal 114 WTGT signal 115 HOLD signal 116 Laser drive signal 601 Optical information recording / reproducing device 603 Controller 608 Modulation signal generation circuit 610 Laser control circuit 613 Laser modulation signal

Claims (4)

[Claims] 1. An optical information recording / reproducing apparatus for recording / reproducing data in sector units using an optical disc, comprising laser power control means for controlling laser output to a set laser power value, and reproducing from the optical disc. A signal amplitude measuring means for measuring a signal amplitude and a laser power value which is different stepwise in one sector are set in the laser power control means,
An optical information recording / reproducing apparatus comprising: an optimum recording power calculating means for measuring a signal from the sector by a signal amplitude measuring means to obtain an optimum recording power of the optical disk. 2. An optical information recording / reproducing apparatus for recording / reproducing data in sector units using an optical disk, wherein the laser power control means responds to control a laser output to a set laser power value, and reproduces from the optical disk. Optimizing the optical disc by setting the signal amplitude measuring means for measuring the generated signal amplitude and the laser power control means for different laser power values in steps in one sector, and measuring the signal from the sector by the signal amplitude measuring means. The optimum recording power calculating means for obtaining the recording power, the error correction number measuring means for obtaining the error number of the reproduction data for each sector of the optical disk, and the near value obtained by the optimum recording power calculating means for each sector are set as the laser power control means. The optimum recording power of the optical disc is determined by setting the number of errors in the sector and measuring the number of errors in the sector by the error correction number measuring means. The optical information recording and reproducing apparatus characterized by comprising a optimal recording power determination means that. 3. The optimum recording power calculation means determines the lower limit and the upper limit of the laser power set in the laser power control means by referring to the recording power written in advance on the optical disk. 2. The optical information recording / reproducing apparatus described in 2. 4. The optical information recording / reproducing apparatus according to claim 1, wherein the optimum recording power calculating means sets a signal to be recorded on the optical disk as a signal including many shortest periods.