JP2003085760A - Information recorder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the optimum recording condition with respect to a linear velocity while making the best use of the special feature of ZCLV. SOLUTION: The device is furnished with a ZCLV writing control part 109 for arranging a plurality of recording zones in the radial direction of an optical disk 102 to perform the write-in with specified linear velocities different for every zone, a reproduced signal evaluating part 108 for evaluating the reproduced signal by reproducing the already recorded part on the preceding zone when the recording zone is changed over or the already recorded part on a new zone, and a recording condition correcting part 107 for correcting the recording condition of the new zone in accordance with the evaluation result obtained by a reproduced signal evaluating part 108, then, the recording condition of the new zone is corrected in accordance with the evaluation result of the reproduced signal evaluating part 108.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recording medium having a constant linear density, for example, CD-R (Compact Disc Recordable).
The present invention relates to an information recording apparatus suitable for use in controlling the recording power of the above.

[0002]

2. Description of the Related Art A CD-R disc is a recording medium having a constant linear density. With such a disc, a constant linear velocity (CL
It is normal to record while rotating with V: Constant Linear Velocity. In this case, since the relative speed between the recording medium and the laser beam is always constant, the recording conditions such as the recording power and the recording pulse width do not need to be changed over the entire surface once they are optimally determined. For this reason, normally, there is no problem in performing test writing while oscillating power in a specific area of the innermost peripheral portion of the disk and using the optimum recording power determined thereby to perform full recording at the same linear velocity.

However, in CLV, since it is necessary to increase the rotation speed toward the inner peripheral portion of the disk, it becomes difficult to rotate the disk at higher speeds. Therefore, the cost of the motor increases, noise and vibration increase, and the design of the servo system becomes difficult. Therefore, a method is adopted in which the rotation speed is not lowered so much even when going to the outer circumference, instead of increasing the rotation speed so much on the inner circumference. In this case, the linear velocity becomes higher toward the outer circumference. Therefore, the zone is divided at an appropriate radial position, the inside of the zone is set as CLV, and the zone CLV (hereinafter, ZCL
A method referred to as V) is adopted.

[0004]

By the way, the above-mentioned Z
With CLV, there are cases in which recording is performed at a linear velocity different from the linear velocity of the inner circumferential area for trial writing. In this case, how to set the power and other recording conditions becomes an issue.

Therefore, conventionally, an apparatus has been developed which performs a predetermined calculation on the test writing result to calculate recording conditions of different linear velocities. However, according to this apparatus, when the relationship of the recording condition with respect to the linear velocity is different from the predetermined calculation relationship due to variations in the film characteristics of the recording medium, variations due to the radius, variations of the recording apparatus, etc. It may not be. Also, a device has been developed that interrupts recording as needed during recording, reproduces the recorded portion, corrects recording conditions, and resumes recording, but optimizes recording conditions in new zones when switching ZCLV zones. The current situation is that it has not yet reached.

The present invention has been made in view of the above circumstances, and while maintaining the characteristic of ZCLV that enables high-speed writing at low rotation speed, the relationship of the recording condition with respect to the linear velocity is the film of the recording medium. An object of the present invention is to provide an information recording apparatus capable of obtaining an optimum recording condition even when the calculation relationship is different from a predetermined calculation relationship due to a characteristic variation, a variation due to a radius, a variation in a recording apparatus, or the like.

[0007]

According to a first aspect of the present invention, there is provided an information recording device for writing information at a substantially constant linear density in a circumferential direction of a disk-shaped recording medium, the radial direction of the recording medium. Zone CLV writing control means for providing a plurality of recording zones and performing writing at different predetermined linear velocities for each zone, and reproduction for evaluating a reproduced signal by reproducing a recorded portion in the immediately preceding zone when switching the recording zones. It is characterized by further comprising a signal evaluation means and a recording condition correction means for correcting the recording condition of the new zone based on the evaluation result by the reproduction signal evaluation means. According to the first aspect of the present invention, the recording condition of the new zone is corrected based on the evaluation result of the reproduction signal evaluation means. Therefore, while maintaining the low rotation speed of ZCLV, high speed writing is possible, Even if the recording conditions are no longer optimal due to variations in the film characteristics of the recording medium, variations due to radii, variations in the recording device, etc., good recording quality can be obtained by correcting the recording conditions. Further, when the zone is switched, since the recorded portion is reproduced and the correction operation is performed, there is no new interruption of recording, and the time loss related to the correction operation is reduced.

According to a second aspect of the present invention, in the information recording apparatus according to the first aspect, trial writing is performed in a predetermined area of the recording medium at a predetermined basic linear velocity, and optimum recording conditions at the basic linear velocity are obtained. When the recording is performed on the recording medium at a linear velocity different from the basic linear velocity, the recording is performed according to the result of performing a predetermined calculation on the optimum recording condition at the basic linear velocity. Recording condition setting means for setting a condition, wherein the recording condition correcting means corrects the recording condition of the new zone set by the recording condition setting means based on the evaluation result of the reproduction signal evaluating means. To do. According to the second aspect of the present invention, the recording condition correction means corrects the recording condition of the new zone set by the recording condition setting means based on the evaluation result of the reproduction signal evaluation means. The initial recording condition can be determined more accurately from the writing result, and better recording quality can be obtained.

According to a third aspect of the present invention, there is provided an information recording device for writing information at a substantially constant linear density in the circumferential direction of a disc-shaped recording medium, wherein a plurality of recording zones are provided in the radial direction of the recording medium. A zone CLV writing control means for writing at a predetermined linear velocity different for each zone, a reproduction signal evaluation means for reproducing a recorded portion in the new zone and evaluating a reproduction signal after switching the recording zone, Recording condition correction means for correcting the recording condition of the new zone based on the evaluation result by the reproduction signal evaluation means. According to the third aspect of the invention, the recording condition of the new zone is corrected based on the evaluation result of the reproduction signal evaluation means. Therefore, while maintaining the low rotation speed of ZCLV, high speed writing is possible, Variations in film characteristics of recording media and variations due to radius,
Even if the recording conditions are not optimal due to variations in the recording device, the recording conditions can be corrected to obtain good recording quality. Further, since the recorded portion of the new zone itself is reproduced and the correction operation is performed, the correction accuracy is high.

According to a fourth aspect of the present invention, in the information recording apparatus according to the third aspect, trial writing is performed in a predetermined area of the recording medium at a predetermined basic linear velocity, and optimum recording conditions at the basic linear velocity are obtained. When the recording is performed on the recording medium at a linear velocity different from the basic linear velocity, the recording is performed according to the result of performing a predetermined calculation on the optimum recording condition at the basic linear velocity. Recording condition setting means for setting a condition, wherein the recording condition correcting means corrects the recording condition of the new zone set by the recording condition setting means based on the evaluation result of the reproduction signal evaluating means. To do. According to the invention described in claim 4, since the recording condition correction means corrects the recording condition of the new zone set by the recording condition setting means based on the evaluation result of the reproduction signal evaluation means, trial writing The initial recording conditions can be determined more accurately from the results, and better recording quality can be obtained.

The invention as defined in claim 5 is from claim 1 to claim 4.
In the information recording apparatus described in any one of 1, the recording state is a value according to a reproduction signal from the recording medium when recording is started on the recording medium based on the recording condition corrected by the recording condition correcting means. Recording state storage means for storing as a target value, while recording information on the recording medium, compares the recording state target value with a value according to a reproduction signal from the recording medium, and records according to the comparison result. Recording power correction means for correcting the power. According to the invention of claim 5, while recording information on the recording medium,
Since the recording power correction means compares the recording state target value with a value according to the reproduction signal from the medium and corrects the recording power according to the comparison result, recording is performed while maintaining the recording state at the time of initial correction. Can be continued, and high quality recording can be performed. Also, since the recording is not interrupted for this correction, there is no new time loss.

The invention as defined in claim 6 is from claim 1 to claim 5.
In the information recording apparatus described in any one of 1, the reproduction signal evaluation means interrupts recording each time a predetermined condition is satisfied, reproduces a recorded portion immediately before the interruption, and evaluates the reproduction signal. The recording condition correction means is characterized by correcting the recording condition based on the evaluation result of the reproduction signal evaluation means and restarting the recording. According to the invention of claim 6,
Since the recording condition correcting means corrects the recording condition based on the evaluation result of the reproduction signal evaluating means and restarts the recording, the recording condition can be constantly corrected by the reproduction signal evaluation of the actual recording, Higher quality recording is possible.

[0013]

1 is a block diagram showing an embodiment of an information recording apparatus according to the present invention. As shown in the figure, the information recording apparatus of the present invention is
U, ROM, RAM, a microcomputer including an input / output port and the like, and a CD-R drive controlled by various mechanisms and circuit parts, which are shown here in a functional block diagram, and the circumference of the optical disc 102. Information shall be recorded at a substantially constant linear density in the direction.

An optical disk 102 such as a CD-R which is a disk-shaped recording medium is rotationally driven by a rotary motor 100. The head 103 focuses a light beam on the recording film of the optical disc 102 to form a recording mark. Further, the optical disc 1 can be moved in the radial direction,
02, it is possible to access a trial writing area and a user data area provided in advance.

A light source (not shown) is mounted on the head 103. As a light source, usually a semiconductor laser (LD: Lase
r Diode) is used. The LD driver 104 modulates the semiconductor laser into a predetermined recording power state Pw with the input pulse wdata signal. The semiconductor laser is modulated between the recording power state and the space power state, whereby recording marks and spaces are formed on the recording film. By reading this, a difference in reflectance occurs and it can be reproduced as an information signal.

The optical disc 102 is provided with a plurality of zones at predetermined positions, and the ZCLV writing control section 109 is provided.
Controls the rotation motor 100 according to each zone to make the recording speed variable. FIG. 7 shows an example of zone division. Here, four zones are provided according to the addresses recorded on the optical disc 102, and 1 zone from the inner circumference.
2x speed (12x), 16x speed (16x), 20x speed (2
0x) and 24x speed (24x) are assigned.

A recording condition setting unit 106 holds recording power information according to each zone. This recording power information may be a predetermined value, but more preferably, a value obtained according to the result of trial writing by the trial writing control unit 105. FIG. 3 is a flowchart showing an operation example of the trial writing control unit 105.
The trial writing is performed in a predetermined area of the optical disc 102, and recording is performed in the predetermined area in step S301 with some recording powers changed. In step S302, the area is reproduced, and a known evaluation scale value "beta" is obtained from the reproduced signal. “Beta” removes low frequency components of the playback signal RF (AC
This corresponds to the symmetry of the upper and lower amplitudes when combined).

FIG. 8 shows the state of the reproduction signal RF depending on the recording power. As the characteristics of the recording film of the optical disc 102,
Assuming that the reflectance decreases at the recording mark, the reproduction signal RF
Assuming that is low in the low reflection part, the reproduction signal RF AC-coupled in a proper recording state has an RF amplitude a = b with vertical symmetry as shown in FIG. Further, when the recording power is excessively high, the recording mark portion becomes long as shown in FIG. 8B, and therefore, when AC coupling is performed, the upper level becomes high and a> b. Further, when the recording power is insufficient, the recording mark portion becomes short as shown in FIG. 8C, and therefore the lower level becomes higher if AC coupling is performed, and a <b
become. The beta value is the amount obtained by normalizing the difference between a and b with the RF amplitude (a + b). That is, “beta ＝ (ab) / (a +
b) ”, if appropriate,“ beta ”is almost“ 0 ”, if power is excessive,“ beta ”is large, and if insufficient,“ beta ”is small.

The description returns to the flowchart of FIG. After measuring "beta" in step S302, step S303
Then, the recording power “Pwopc [0]” at which “beta” becomes the predetermined target value “betaT” is obtained. Although “betaT” is close to “0”, “0” is not optimal depending on the recording film of the optical disc 102 and a certain value is optimal. Therefore, it is generally set to a different value for each type of the optical disc 102. Since this recording power “Pw opc [0]” is the optimum power at the linear velocity at which trial writing was performed, the recording power at the linear velocity of each zone was calculated based on “Pw opc [0]”. Ask by. In step S304, the recording power of each zone "Pw o
pc [n] (n is zone number 1,2,3, ..) ”is the recording power“ Pw
Multiply opc [0] ”by a predetermined coefficient“ L [n] ”, and obtain“ Pw opc [n] = P
w opc [0] * L [n] ”, and the recording condition setting unit 106
Give to.

Description will be returned to FIG. A reproduction signal evaluation unit 108 reproduces the last part of the current zone and measures “beta” when the ZCLV writing control unit 109 switches the zone during recording, and compares it with the target value “betaT”. The recording condition correction unit 107 corrects the recording power of the new zone according to the result. In Figure 2, zone numbers "n" through "n
Recording condition correction unit 1 when switching to "+1" occurs
07, a reproduction signal evaluation unit 108, and a power correction operation example by the ZCLV write control unit 109 are shown in a flowchart.

In FIG. 2, first, in step S201, the last part of the current zone "n" is reproduced, and then in step S202.
To measure beta. Then, in step S203, "bet
Multiplying the result of comparison between “a” and “betaT” by a predetermined coefficient K, the default recording power “Pw opc [n +
1] ”is modified to obtain“ Pw [n + 1] ”. Specifically,“ bet
If “a” is smaller than “betaT”, the power is corrected so as to be increased. The initial setting power is a predetermined value or a value determined by trial writing and is stored in the recording condition setting unit 106. The recording power corrected in step S204 is set to the zone "n + 1".
And the recording power of. As described above, the reproduction signal recorded immediately before is evaluated and the recording power of the next zone is corrected.

In the flow chart shown in FIG. 4, the power correction operation by the recording condition correction unit 107, the reproduction signal evaluation unit 108, and the ZCLV write control unit 109 when the zone number "n" is switched to "n + 1". For example: Here, recording is first interrupted in step S401. In step S402, the recording power of the new zone "n + 1" is set to the initial setting power "Pw opc [n + 1]", and recording is restarted in the new zone "n + 1" in step S403. The operation up to this point is the same as that of the conventional example, and the power correction operation of the present invention is performed thereafter.

That is, 1 sector information is recorded in step S404, the 1 sector is reproduced by the reproduction signal evaluation unit 108 in step S405, and the 1 sector information is reproduced in step S406.
measure beta. Then, in step S407, "bet
The recording power “Pw [n + 1]” of the zone “n + 1” is modified by the amount obtained by multiplying the comparison result of “a” and “betaT” by the predetermined coefficient “K” and the new “Pw [n + 1] ”. Specifically,“ bet
If “a” is smaller than “betaT”, the power is corrected so as to be increased. By repeating the operations of steps S404 to S407 described above 10 times (step S408),
The recording power is corrected so that “beta” becomes equal to “betaT”. The coefficient "K" is a coefficient for controlling the convergence speed. If it is large, the amount of correction for one time will be large and the convergence will be fast, but if it is too large, it will be sensitive to measurement errors
If it is too small, convergence will be slow.

In the flow chart shown in FIG. 2, the recording power of the new zone is corrected from the reproduction evaluation of the immediately preceding zone before switching and writing the zone, but in FIG. 4, the recording power of the new zone is changed after the zone is switched. Playback evaluation is performed to correct power. Therefore, since the power shown in FIG. 4 is the power evaluated by the current zone,
Although the recording power can be corrected more accurately, a relatively large number of recording interruptions cause a large loss time for power correction. Further, in FIG. 2, there is an effect that a loss time for power correction hardly occurs.

Further, after the power correction operation shown in FIGS. 2 and 4, while recording information in the new zone, the recording is periodically interrupted, and the portion recorded immediately before is reproduced and reproduced. It is also possible to evaluate the signal and correct the recording power according to the evaluation result. In this case, the processing from step S404 to step S407 may be periodically executed. The power correction operation is not limited to be started every predetermined time, but may be performed every time a certain condition is satisfied, such as when a predetermined temperature change occurs. This allows more accurate power correction.

FIG. 5 is a block diagram showing another embodiment of the information recording apparatus according to the present invention, and blocks designated by the same reference numerals as those shown in FIG. 1 are the same as those shown in FIG. Here, a recording state detection unit 110, a recording power correction control unit 111, and a recording state target value storage unit 112 are added to the configuration shown in FIG.
The power is corrected by detecting the recording state from the reproduction signal during recording. As the target value, the recording state at the stage when the initial power is corrected by the operation shown in FIGS. 2 and 4 after zone switching is applied. Immediately after the initial power is corrected, the optimum recording state is set, so this is set as the target value. After that, even if the recording state changes due to temperature variation or sensitivity variation of the recording film, it can be corrected by detecting the recording state from the reproduction signal during recording and correcting the power. This does not interrupt the recording, so there is no time loss.

Specifically, the recording state detector 110 samples the reproduced signal being recorded at a predetermined timing,
A value normalized by the recording power is used as a recording state detection value (called B value). This operation is shown in FIG. That is, the portion where the "LD power" is at a high level is the portion where the recording pulse occurs, and the predetermined timing (○)
The playback signal is sampled at (point). Furthermore, in order to cancel the difference in the reproduction light amount level due to the power level,
Divide (normalize) by the recording power. As a result, the recording state detection value (B) is at a high level because the formation of recording marks (low reflection) is not sufficient if the power is insufficient, and is at a low level because the mark formation is excessive when the power is excessive.

On the other hand, the B level immediately after resuming the recording after the zone switching has occurred and the initial power correction is completed is stored in the recording state target value storage unit 112 as the target B level "BT". The recording power correction control unit 111 periodically measures the B level, compares it with the target B level “BT”, and corrects the recording power according to the comparison result. This correction operation is shown in the flow chart of FIG. The flowchart shown in FIG. 6 is
This is a flow of operations after the recording is restarted after the initial power correction of the zone “n + 1” is completed.

That is, first, in step S501, the current "B value" (that is, the B value immediately after resuming recording) is stored as the target B level "BT". And regularly step S
The "B value" is measured in 503, and this "B value" is measured in step S504.
The recording power “Pw [n + 1]” is corrected by multiplying the comparison result between “value” and “BT” by a predetermined coefficient “K2”. If it is larger, the power is insufficient, so the recording power correction control unit 111 is controlled to increase the recording power.The operations of steps S503 and S504 are executed, for example, about once a second (step S50).
By doing 2), the recording power is always corrected so that the “B value” becomes equal to “BT”, that is, the target value.

[0030]

As described above, according to the first aspect of the present invention, while maintaining the characteristic that the ZCLV can be written at a high speed even at a low rotation speed, variations in the film characteristics of the recording medium and variations due to the radius, Due to variations in the recording device,
Even if the recording conditions are not optimal, the recording conditions can be modified to obtain good recording quality. Further, when the zone is switched, since the recorded portion is reproduced and the correction operation is performed, there is no new interruption of recording, and the time loss related to the correction operation is reduced.

According to the second aspect of the invention, the initial recording condition can be determined more accurately from the test writing result, and a better recording quality can be obtained.

According to the invention of claim 3, ZCLV
Even if the recording conditions are no longer optimal due to variations in film characteristics of recording media, variations due to radius, variations in recording device, etc. Good recording quality can be obtained. Further, since the recorded portion of the new zone itself is reproduced and the correction operation is performed, the correction accuracy is high.

According to the invention described in claim 4, since the recording condition of the new zone is corrected based on the evaluation result, the initial recording condition can be determined more accurately from the test writing result, and the better recording quality can be obtained. Is obtained.

According to the fifth aspect of the present invention, while recording information on the recording medium, the recording state target value is compared with the value according to the reproduction signal from the medium, and the recording power is corrected according to the comparison result. Since this is done, it is possible to continue recording while maintaining the recording state at the time of initial correction, and it is possible to perform higher quality recording. Also, since the recording is not interrupted for this correction, there is no new time loss.

According to the sixth aspect of the present invention, the recording condition is corrected and the recording is restarted based on the evaluation result. Therefore, the recording condition is constantly corrected by evaluating the reproduction signal of the actually recorded signal. Therefore, high quality recording is possible.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of an information recording apparatus in the present invention.

FIG. 2 is a flowchart cited to explain the operation of the embodiment shown in FIG.

FIG. 3 is a flowchart cited to explain the operation of the embodiment shown in FIG.

FIG. 4 is a flowchart cited to explain the operation of the embodiment shown in FIG.

FIG. 5 is a block diagram showing another embodiment of the information recording apparatus in the present invention.

FIG. 6 is a flowchart cited to explain the operation of the embodiment shown in FIG.

FIG. 7 is a diagram cited for explaining the operation of the embodiment of the present invention, showing an example of zone division.

FIG. 8 is a diagram quoted for explaining the operation of the embodiment of the present invention, and shows the state of a reproduction signal RF according to recording power.

FIG. 9 is a diagram cited for explaining the operation of the embodiment of the present invention, in which the relationship between the reproduction signal RF and the LD power is shown.

[Explanation of symbols]

100 rotation motor 102 optical disc 103 head 104 LD driver 105 Trial writing control unit 106 recording condition setting section 107 recording condition correction unit 108 playback signal evaluation unit 109 ZCLV write controller 110 recording state detector 111 recording power correction controller 112 recording state target value storage unit

Continued front page    F term (reference) 5D090 AA01 BB04 CC01 CC05 DD03                       DD05 EE01 JJ12 KK03                 5D119 AA23 DA01 DA09 EC09 HA16                       HA19 HA45                 5D789 AA23 DA01 DA09 EC09 HA16                       HA19 HA45

Claims (6)

[Claims] 1. An information recording device for writing information at a substantially constant linear density in a circumferential direction of a disk-shaped recording medium, wherein a plurality of recording zones are provided in a radial direction of the recording medium, and each zone has a predetermined predetermined number. Zone CLV writing control means for writing at a linear velocity, reproduction signal evaluation means for reproducing a recorded portion in the immediately preceding zone to evaluate a reproduction signal when switching the recording zone, and evaluation results by the reproduction signal evaluation means And a recording condition correction means for correcting the recording condition of the new zone based on the information recording device. 2. A test writing unit for performing test writing in a predetermined area of the recording medium at a predetermined basic linear velocity to determine optimum recording conditions at the basic linear velocity, and the basic linear velocity for the recording medium. When recording at different linear velocities, a recording condition setting means for setting recording conditions according to a result of performing a predetermined calculation on the optimum recording condition at the basic linear velocity, and the recording condition correcting means, 2. The information recording apparatus according to claim 1, wherein the recording condition of the new zone set by the recording condition setting means is corrected based on the evaluation result of the reproduction signal evaluation means. 3. An information recording device for writing information in a substantially constant linear density in the circumferential direction of a disk-shaped recording medium, wherein a plurality of recording zones are provided in the radial direction of the recording medium, and different predetermined zones are provided for each zone. Zone CLV write control means for writing at a linear velocity, reproduction signal evaluation means for evaluating the reproduction signal by reproducing the recorded portion in the new zone after switching the recording zone, and evaluation result by the reproduction signal evaluation means And a recording condition correction means for correcting the recording condition of the new zone based on the information recording device. 4. A test writing unit for performing test writing in a predetermined area of the recording medium at a predetermined basic linear velocity to determine optimum recording conditions at the basic linear velocity, and the basic linear velocity in the recording medium. When recording at different linear velocities, recording condition setting means for setting recording conditions according to the result of performing a predetermined calculation on the optimum recording conditions at the basic linear velocity, 4. The information recording apparatus according to claim 3, wherein the recording condition of the new zone set by the recording condition setting means is corrected based on the evaluation result of the reproduction signal evaluation means. 5. A recording state storage for storing, as a recording state target value, a value corresponding to a reproduction signal from the recording medium when recording is started on the recording medium based on the recording condition corrected by the recording condition correcting means. Means for recording information on the recording medium, the recording state target value,
5. A recording power correction unit that compares a value according to a reproduction signal from the recording medium and corrects the recording power according to the comparison result, according to any one of claims 1 to 4. The information recording device described in the item. 6. The reproduction signal evaluation means interrupts the recording each time a predetermined condition is satisfied, reproduces the recorded portion immediately before the interruption, and evaluates the reproduction signal, and the recording condition correction means comprises the reproduction condition. Correct recording conditions based on the evaluation result of the signal evaluation means and restart recording,
The information recording apparatus according to any one of claims 1 to 5, characterized in that: