JP2003203343A - Optical disk device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To quickly optimize a recording condition in a limited PCA area with respect to an optical disk device. <P>SOLUTION: A controller 30 records test data in a PCA area of the optical disk 10 and selects a recording condition which minimizes the jitter of the test data. The controller 30 takes a recording power as a fixed value and varies a recording strategy to select the most suitable recording strategy. For example, the recording power is fixed to 11 mW and the pulse widths of a top pulse and multi-pulses are changed by frames to optimize the pulse widths of the top pulse and multi-pulses. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical disk device, and more particularly to optimizing recording conditions when recording data on a recordable optical disk.

[0002]

2. Description of the Related Art Conventionally, CD-R / RW and DVD-R
There is known a technique for optimizing recording conditions such as recording power and recording pulse width when recording data on a recordable optical disc such as / RW. Specifically, test data is recorded (trial writing) in a predetermined area (PCA area) of the optical disk, the test data is reproduced, and a recording condition that gives the best reproduced signal quality is selected. A β value, jitter, an error rate, or the like is used as the reproduction signal quality.

For example, in Japanese Unexamined Patent Publication No. 2000-207742, when data is recorded by a multi-pulse consisting of one or more pulse trains, various combinations of the pulse width of the leading pulse, the pulse width of the subsequent multi-pulse and the recording power are used. A technique for recording test data and optimizing these three parameters according to the result is described.

However, if not only the recording power but also the pulse width of the first pulse (top pulse) and the pulse width of the subsequent multi-pulses are optimized, the combination becomes huge, and there is a problem that optimization takes time. is there. Further, in a write-once disc such as a CD-R or a DVD-R, the PCA area for trial writing is limited, which makes physical optimization difficult.

Therefore, conventionally, a recording strategy (a pulse width of a top pulse or a multi-pulse) uses a fixed value for each optical disk or each recording speed, and only the recording power is variously changed to record the test data. We are optimizing.

[0006]

However, in the fixed recording strategy set for each optical disk or each recording speed, when recording is performed by changing only the recording power,
Due to variations in the characteristics of the optical pickup, there has been a problem that optimum recording conditions cannot always be obtained in all optical disk devices. In other words, if the recording strategy is fixed, the variation in the optical disk device cannot be sufficiently absorbed no matter how much the recording power is changed, and even if the jitter is used as the reproduction signal quality, it is sufficient to optimize the recording power. The reality is that small jitter cannot be obtained.

The present invention has been made in view of the problems of the above-mentioned prior art, and its object is to make it possible to further optimize the recording conditions in a limited PCA area in a short time, and to improve the recording quality. It is to provide an optical disk device that can be improved.

[0008]

In order to achieve the above object, the present invention is an optical disk apparatus for recording test data in a predetermined area of an optical disk and optimizing recording conditions based on the reproduction signal quality of the test data. And a means for recording the test data by variously changing the recording strategy with a fixed recording power, and a means for selecting an optimum recording strategy at the fixed recording power based on the reproduction signal quality of the test data. And

It is preferable that the means for recording the test data record by changing the pulse widths of the top pulse and the multi-pulse.

Further, it is preferable that the means for selecting the optimum recording strategy optimizes the pulse widths of the top pulse and the multi-pulse based on the reproduction signal quality.

The optical disk device of the present invention may further comprise means for selecting the fixed recording power from a plurality of predetermined powers.

As described above, in the present invention, the recording conditions are not optimized by fixing the recording strategy and changing the recording power, but by fixing the recording power and changing the recording strategy. To optimize When recording data on an optical disc, the optimum recording power is not one but exists for each recording strategy. That is, the optimum recording power in one recording strategy is not necessarily optimum in another recording strategy. On the other hand, when focusing on a certain recording power, the reproduction signal quality is not good when recording with that recording power under a certain recording strategy, but by selecting another recording strategy, the reproduction signal quality is improved and the recording power is optimized for the recording. It is also possible to change to power. The present invention optimizes the recording condition by fixing the recording power and selecting the recording strategy based on such characteristics. By fixing the recording power, the time required for optimization and the number of test areas can be suppressed.

The present invention is a CD-R drive or a DVD-R.
It can be applied to a recordable optical disk device such as a drive.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing the configuration of the optical disk device according to this embodiment. A recordable optical disc 10 such as a CD-R / RW or a DVD-R / RW is rotationally driven by a spindle motor (not shown).

The pickup (PU) 12 is arranged to face the optical disc 10 and includes a laser diode (LD) for irradiating the surface of the optical disc 10 with laser light. The laser diode is a laser diode drive circuit (LDD) 32.
When the data is reproduced, the laser beam having the reproducing power is emitted, and when the data is recorded, the laser beam having the recording power (recording power> reproducing power) is emitted. Further, the pickup 12 has a photodetector that converts the laser light reflected from the optical disc 10 into an electric signal, and outputs a reproduction signal to the servo detection unit 14 and the RF detection unit 20.

The servo detector 14 generates a tracking error signal and a focus error signal based on the signal from the pickup 12 to generate the tracking error signal and the tracking error signal, respectively.
6 and the focus control unit 18. The tracking control unit 16 drives the pickup 12 in the track direction of the optical disc 10 based on the tracking error signal to bring it into the on-track state. In addition, the focus control unit 18
Drives the pickup 12 in the focus direction based on the focus error signal to bring it into the on-focus state. For example, in the case of a four-division photo detector, a tracking error signal is generated from the difference between the detectors divided in the radial direction, and a focus error signal is generated from the difference between the detectors divided in the circumferential direction. Of course, other schemes are possible.

The RF detector 20 amplifies the signal from the pickup 12 to generate a reproduction RF signal, and outputs it to the equalizer (EQ) 22. The equalizer 22 is a reproduction RF.
A predetermined frequency of the signal, specifically, the amplitude of the 3T signal is boosted and output to the binarizer 24. The binarizer 24 binarizes the boosted RF signal and outputs the binarized RF signal to the decoder 26 and the jitter measuring unit 28. The decoder 26 includes a PLL circuit, generates a synchronous clock signal, demodulates the binarized signal, and outputs the binarized signal to the controller 30.

The controller 30 controls the operation of each unit such as the servo detector 14, the RF detector 20, the LDD 32, and outputs the demodulated data from the decoder 26 to a host device such as a personal computer.

Further, the controller 30 drives the LDD 32 based on the recording data from the host device to record the data at the time of recording the data. For example, in the case of DVD-R, 3
Of the data of T to 14T (T is a bit length), 3T is recorded by a monopulse (top pulse only), and 4T or more is recorded by a multipulse.

Further, when recording data, the controller 30 optimizes the recording condition for recording the data prior to the data recording, and the LD is set under the optimized recording condition.
The D32 and the LD in the pickup 12 are driven. In the present embodiment, when optimizing the recording conditions, the controller 30 sets the recording power to a fixed value and changes the recording strategy to select the optimum recording strategy. Specifically, using a certain recording power, the pulse widths of the top pulse and the multi-pulse are variously changed to record the test data, and the jitter in the pulse width is detected by the jitter measuring section 28. Then, the top pulse width and multi-pulse width that minimize the jitter are selected as the optimum recording strategy, and data is recorded in the data area with the recording power and the selected recording strategy.

2 and 3 show the relationship between the recording strategy and the recording power. FIG. 2 shows a recording pulse and three types of recording strategies A to A corresponding to the recording pulse.
It is a pulse waveform of C. (A) is a recording pulse waveform, which is a pulse modulated based on the recording data supplied from the host device. In the case of a DVD-R or the like, there are 3T to 14T (T is a bit length) as a recording pulse, and 3T is shown in FIG.
T and 6T are shown. (B) to (d) are pulse waveforms of three recording strategies A, B, and C. Shortest 3
The T pulse is recorded with only a single top pulse, and the 6T pulse is recorded with a combination of the top pulse and the subsequent multi-pulses. In the recording strategy A shown in (b), data is recorded with a pulse width of the top pulse of 1.7T and a pulse width of the multipulse of 0.7T. In the recording strategy B shown in (c), data is recorded with the pulse width of the top pulse being 1.5T and the pulse width of the multipulse being 0.55T. In the recording strategy C shown in (d), the top pulse has a pulse width of 1.1 T and the multi-pulse has a pulse width of 0.4 T to record data. The recording strategy A has the longest pulse width for both the top pulse and the multi-pulse, and the recording strategy C has the shortest pulse width for both the top pulse and the multi-pulse.

FIG. 3 shows the relationship between the recording power and the jitter when data is recorded with the recording strategies A to C. When recording with recording strategy A, the recording power that minimizes jitter is PA, when recording data with recording strategy B, the recording power that minimizes jitter is PB, and when recording data with recording strategy C, the jitter is The minimum recording power is PC and PA <PB <PC.
In the recording strategy C, both the top pulse and the multi-pulse have a short pulse width, and therefore a larger recording power is required to record the data. From this, it is understood that the optimum recording power exists for each recording strategy, and conversely, when the recording power is given, the optimum recording strategy exists for this recording power. For example, when PB is given as the recording power, the jitter can be minimized by using the recording strategy B instead of the recording strategy A and the recording strategy C. The controller 30 of the present embodiment utilizes such characteristics to optimize the recording conditions with a fixed recording power and a variable recording strategy.

FIG. 4 shows a specific processing flow chart of the controller 30. First, the type of the loaded optical disc 10 is read from the control data zone, and the recording power is set according to the type of the read optical disc and the set recording speed (S101). For example, if the optical disc 10 is a maker A DVD-R and the recording speed is double speed, the recording power is fixed to 11 mW, and if the maker B DVD-R is the recording speed is 1 × speed, it is fixed to 9 mW. And so on. Conventional OPC (Opti
It should be noted that although the recording power is optimized in the mum power control), the recording power is not optimized in this embodiment and a predetermined fixed value is used.

After setting the fixed recording power, the test data is recorded (trial writing) in 16 frames of the PCA area while changing the recording strategy (S102). There are several ways to change the recording strategy, for example 1
Up to 8 frames, the pulse width of the multi-pulse is fixed within one frame, the pulse width of the top pulse is changed by a predetermined change width and recorded, and during the 9th to 16th frames, the pulse width of the top pulse is fixed within one frame. Then, the pulse width of the multi-pulse is changed by a predetermined change width and recorded. Specifically, it is as follows.

<First frame> Multipulse 0.7T fixed top pulse 1.0T to 1.7T sequentially changed in 0.1T width <Second frame> Multipulse 0.65T fixed top pulse 1.0T to 1 Change to 0.7T <3rd frame> Multipulse 0.6T fixed top pulse Change from 1.0T to 1.7T <8th frame> Multipulse 0.35T fixed top pulse Change from 1.0T to 1.7T Yes <9th frame> Multi-pulse 0.7T to 0.35T 0.05T
Top pulse that varies with width 1.7T fixed <10th frame> Multipulse 0.7T to 0.35T top pulse fixed 1.6T <11th frame> Multipulse varied from 0.7T to 0.35T Top pulse fixed at 1.5T <16th frame> Multipulse Top pulse that changes from 0.7T to 0.35T Top pulse fixed at 1.0T As described above, the pulse width of the top pulse and multipulse is changed within 16 frames. After recording the test data, the jitter measuring section 28 measures the jitter and supplies it to the controller 30. Since 8 jitters are obtained per frame, a total of 128 jitters are supplied to the controller 30 in 16 frames. Controller 30
Extracts the frame with the minimum jitter from the 1 to 8 frames and the frame with the minimum jitter from the 9 to 16 frames (S103). Then, the multi-pulse width of the minimum jitter frame in the extracted 1 to 8 frames is set as the optimum multi-pulse width, and the top pulse width of the minimum jitter frame in the 9 to 16 frames is selected as the optimum top pulse width (S104). For example, when the frame having the smallest jitter in the 1st to 8th frames is the second frame and the frame having the smallest jitter in the 9th to 16th frames is the 10th frame, the optimum multi-pulse width is 0.
It becomes 65T, and the optimum top pulse width becomes 1.6T.

After selecting the top pulse width and multi-pulse width as described above, the controller 30 sets the top pulse width and multi-pulse width of the optimum recording strategy to S104.
Data is recorded with the pulse width selected in step S1 and the recording power set to the recording power (11 mW) in step S101 (S105).

As described above, by fixing the recording power and changing the recording strategy variously to select the recording strategy with the best jitter, the recording conditions can be quickly optimized within a fixed PCA area. .

The embodiment of the present invention has been described above, but the present invention is not limited to this, and various modifications can be made. For example, although jitter is used as the reproduction signal quality in this embodiment, the error rate of the test data may be calculated and the recording strategy that minimizes the error rate may be selected. The β value can also be used.

When changing the recording strategy,
By changing the multi-pulse width in 1 to 8 frames to find the multi-pulse width that minimizes the jitter, the
In 16 frames, the optimized multi-pulse width may be fixed and the top pulse width may be variously changed to record the test data, and the top pulse width of the frame in which the jitter is minimum in 9 to 16 frames may be selected.

Further, in the present embodiment, the recording power is fixed for each type of optical disc and recording speed, but it is also possible to fix the recording power (for example, 11 mW) regardless of the type and recording speed of the optical disc. is there. The gist of the present invention is to optimize the recording condition only by changing the recording strategy without changing the recording power.

Further, a plurality of recording powers are prepared in advance,
It is also possible to record the test data with these recording powers under a standard recording strategy, select the recording power with the best reproduction quality, and then shift to the processing shown in FIG. As a standard recording strategy, for example, strategy B shown in FIG. 2C can be used. As a plurality of recording powers prepared in advance, four powers of 8 mW, 10 mW, 12 mW, and 14 mW are used, for example. Then, the controller 30 records the test data by changing the recording power, and selects the recording power of the smallest frame among the obtained jitters. After that,
The processes of S102 to S105 in FIG. 4 may be performed.
Even in this case, since it is only necessary to select the best recording power from a plurality of fixed recording powers without optimizing the recording power, it is possible to change both the recording power and the recording strategy as in the conventional method. The time required for processing and the number of physical frames are suppressed as compared with the case of selecting the combination.

[0033]

As described above, according to the present invention,
The recording conditions can be optimized in a limited test area and in a short time. This enables high quality data recording.

[Brief description of drawings]

FIG. 1 is a configuration block diagram of an embodiment.

FIG. 2 is a timing chart showing a relationship between a recording pulse and a recording strategy.

FIG. 3 is a graph showing the relationship between the recording strategy, the recording power, and the jitter.

FIG. 4 is a processing flowchart of the embodiment.

[Explanation of symbols]

10 optical disk, 12 pickup (PU), 14
Servo detection unit, 16 tracking control unit, 18 focus control unit, 20 RF detection unit, 22 equalizer (EQ), 24 binarizer, 26 decoder, 28 jitter measurement unit, 30 controller, 32 laser diode drive circuit (LDD) .

   ─────────────────────────────────────────────────── ─── Continued front page    F term (reference) 5D090 AA01 BB03 BB05 CC01 EE11                       JJ12 KK03 KK20                 5D119 AA23 BA01 BB02 BB04 HA19                       HA45                 5D789 AA23 BA01 BB02 BB04 HA19                       HA45

Claims (4)

[Claims] 1. An optical disk device for recording test data in a predetermined area of an optical disk and optimizing recording conditions based on the reproduction signal quality of the test data, wherein the recording strategy is variously changed with a fixed recording power to perform the test. An optical disc apparatus comprising: a unit for recording data; and a unit for selecting an optimum recording strategy at the fixed recording power based on the reproduction signal quality of the test data. 2. The optical disk device according to claim 1, wherein the test data recording means changes the pulse widths of the top pulse and the multi-pulse for recording. 3. The optical disk device according to claim 1, wherein the means for selecting the optimum recording strategy optimizes the pulse widths of the top pulse and the multi-pulse based on the reproduction signal quality. 4. The optical disk device according to claim 1, further comprising a unit that selects the fixed recording power from a plurality of predetermined powers.