JPH11126340A - Reproducing method, recording and reproducing method, and reproducing device and recording and reproducing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To shorten a processing time by setting intensities of a reproducing light to be irradiated on plural areas in accordance with the result of first trial readings respectively and updating the intensities of the reproducing light set by a first reproducing light intensity setting procedure based on the result of a second trial reading in the area of one part in among the plural areas after executing the first reproducing light intensity setting procedure respectively. SOLUTION: When it is recognized that an optical disk is loaded, a control part 14 performs initial settings of a recording power and a reproducing power and, thereafter, it moves to an ordinary recording and reproducing operation. In the initial setting of the reproducing power, trial readings are performed in plural times and error rates of reproduced signals are obtained every test area and every time. Next, ranges of reproducing powers in which error rates becomes tolerable values are calculated as to respective test areas and center values of these ranges are obtained as optimum reproducing powers every test area. Moreover, optimum recording powers are obtained by performing the initial setting of the recording power similarly to be stored in a storage part 15.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reproducing method, a recording / reproducing method, and a reproducing apparatus for recording and reproducing information on and from an optical recording medium while setting the intensity of light to be irradiated.
The present invention relates to a recording / reproducing device.

[0002]

2. Description of the Related Art Optical disks capable of storing data at a high density and capable of processing information at a high speed have attracted attention as audio and image applications and as external memories of computers. A system including a magneto-optical disk in which information can be rewritten in an external memory of the computer and a drive device (recording / reproducing device) thereof has rapidly spread.

In recording by this recording / reproducing apparatus, a rotation-controlled magneto-optical disk is irradiated with a recording light beam modulated at a high frequency, and a recording mark is formed in a small area temporarily heated at the center of a light spot. Is formed. Playback is
This is realized by irradiating a rotation-controlled magneto-optical disk with a light beam for reproduction having a relatively low intensity, and detecting reflected light of the light beam that changes depending on the presence or absence of a recording mark.

Generally, in a recording / reproducing apparatus, the rotation speed of a magneto-optical disk is controlled to a constant value. In this case, since the relative speed between the magneto-optical disk and the light spot changes depending on the radial position of the disk, the intensity of the light beam is increased when the area to be recorded or reproduced is located on the outer peripheral side of the magneto-optical disk. On the other hand, when the region is located on the inner peripheral side of the magneto-optical disk, the intensity of the light beam is changed according to the irradiation position, such that the intensity of the light beam is reduced. Thereby, recording or reproduction can be performed under the same conditions regardless of the position on the magneto-optical disk.

[0005]

Incidentally, magneto-optical disks have different recording and reproducing sensitivities due to manufacturing variations. In other words, from the viewpoint of the recording / reproducing apparatus, the intensity of a light beam capable of forming a recording mark in an appropriate shape (optimum recording power) or the intensity of a light beam capable of appropriately detecting a recording mark (optimum recording power) by each magneto-optical disk. Reproduction power), and the tendency of these optimum powers depending on the radial position.

Therefore, in the recording / reproducing apparatus, it is necessary to check the optimum recording power and the optimum reproducing power for each loaded magneto-optical disk, and to measure how much the power differs depending on the radial position. Actually, these optimum powers and their tendency are obtained by trial recording (test writing) or trial reproduction (test reading) in a plurality of test areas at different radial positions.

[0007] However, the recording and reproducing sensitivity is not only unique to the magneto-optical disk but also varies according to changes in the environmental temperature. For example, the temperature difference between the active recording / reproducing apparatus and the magneto-optical disk just loaded may be about 10 ° C., and particularly until the magneto-optical disk warms up and the temperature becomes steady thereafter. The recording sensitivity and the reproduction sensitivity of the magneto-optical disk change by 5% in terms of the light beam intensity.

Therefore, in order to follow the sensitivity of the magneto-optical disk, it is necessary to reset the recording power and the reproducing power immediately after the recording disk is loaded, at regular intervals, or every time a temperature change is recognized. It is desirable that these settings be made relatively frequently at a relatively short time interval or for each small temperature change in accordance with a magneto-optical disk that is easily affected by a temperature change.

However, as described above, in the power setting, since a considerably complicated process such as movement of the head and evaluation of the measurement result is performed for each of a plurality of areas, the recording / reproducing apparatus should perform the operation under the instruction of the user. Recording and playback operations are interrupted for a certain period of time. If such interruptions occur frequently, a reduction in the data transfer rate, that is, a reduction in the performance of the device, cannot be avoided.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and provides a reproducing method, a recording / reproducing method, a reproducing apparatus, and a recording / reproducing apparatus for reducing a processing time when updating an optimum recording power or an optimum reproducing power. The purpose is to provide.

[0011]

According to a first aspect of the present invention, first test reading is performed in a plurality of areas of an optical recording medium, and irradiation is performed on the plurality of areas in accordance with the result of the first test reading. After performing the first reproduction light intensity setting procedure for setting the reproduction light intensity to be performed and the first reproduction light intensity setting procedure, a second test reading is performed in some of the plurality of areas. A second reproduction light intensity setting procedure for updating the reproduction light intensity set in the first reproduction light intensity setting procedure based on the result of the second test reading; and a set or updated reproduction light intensity. And a reproducing procedure for reproducing information from the optical recording medium.

According to a second aspect of the present invention, in the reproduction method according to the first aspect, the optical recording medium is an optical disk, and the plurality of areas are located at different radial positions of the optical recording medium. In the reproduction light intensity setting procedure, the reproduction light intensity to be applied to the plurality of regions and the respective regions of the optical recording medium other than the plurality of regions is set according to the result of the first test reading. And

According to a third aspect of the present invention, in the reproducing method according to the first or second aspect, in the second reproducing light intensity setting procedure, the change rate of the reproducing light intensity to be irradiated to a part of the region is set. And updating the reproduction light intensity set in the first reproduction light intensity setting procedure to a value changed according to the rate of change. According to a fourth aspect of the present invention, in the reproducing method according to any one of the first to third aspects,
The second reproduction light intensity setting procedure is executed when a predetermined time has elapsed after the first reproduction light intensity setting procedure was executed or after the first reproduction light intensity setting procedure was executed. It is characterized in that the temperature change of the recording medium exceeds a predetermined value.

According to a fifth aspect of the present invention, first test writing and first test reading are performed in a plurality of areas of an optical recording medium, and the plurality of areas are irradiated according to the result of the first test writing. A first light intensity setting procedure for setting respective recording light intensities to be set, and respectively setting reproduction light intensities to be applied to a plurality of regions according to a result of the first test reading; Is performed, a second test writing is performed in some of the plurality of areas, and the recording light intensity and the reproduction set in the first light intensity setting procedure are set based on the result of the second test writing. A second light intensity setting procedure for respectively updating the light intensity, recording information on the optical recording medium with the set or updated recording light intensity, and reproducing information from the optical recording medium with the set or updated reproduction light intensity Recording and playback procedures That.

According to a sixth aspect of the present invention, in the recording / reproducing method according to the fifth aspect, the optical recording medium is an optical disk, and the plurality of areas exist at different radial positions of the optical recording medium. In the first light intensity setting procedure, according to the result of the first test writing, the recording light intensities to be applied to the plurality of areas and the respective areas of the optical recording medium other than the plurality of areas are set, respectively. The reproduction light intensity to be applied to a plurality of areas and each area of the optical recording medium other than the plurality of areas is set in accordance with the result of one test reading.

According to a seventh aspect of the present invention, in the recording / reproducing method according to the fifth or sixth aspect, in the second light intensity setting procedure, the change in the intensity of the recording light to be applied to a part of the area is performed. The rate is obtained, and the recording light intensity set in the first recording light intensity setting procedure and the reproduction light intensity set in the first reproduction light intensity setting procedure are updated to values changed according to the change rate. It is characterized by doing.

According to an eighth aspect of the present invention, in the recording / reproducing method according to any one of the fifth to seventh aspects, the second light intensity setting procedure is executed by the first light intensity setting step. The method is characterized in that a predetermined time has elapsed since the execution of the light intensity setting procedure, or that a temperature change of the optical recording medium has exceeded a predetermined value after the execution of the first recording light intensity setting procedure. .

According to a ninth aspect of the present invention, the first test reading is performed in a plurality of areas of the optical recording medium, and the reproduction light intensity to be applied to the plurality of areas is determined according to the result of the first test reading. After the operation of the first reproduction light intensity setting means and the first reproduction light intensity setting means, the second test reading is performed in some of the plurality of areas, and the second test reading is performed. A second reproduction light intensity setting unit that updates the reproduction light intensity set by the first reproduction light intensity setting unit based on the result; and a set or updated reproduction light intensity.
Reproducing means for reproducing information from the optical recording medium.

According to a tenth aspect of the present invention, in the reproducing apparatus according to the ninth aspect, the optical recording medium is an optical disk, and the plurality of areas are present at different radial positions of the optical recording medium. The reproducing light intensity setting means sets the reproducing light intensity to be applied to the plurality of areas and the respective areas of the optical recording medium other than the plurality of areas according to the result of the first test reading. And

According to an eleventh aspect of the present invention, in the reproducing apparatus according to the ninth or tenth aspect, the second reproducing light intensity setting means changes the rate of change of the reproducing light intensity to be irradiated to a partial area. And updating the reproduction light intensity set by the first reproduction light intensity setting means to a value changed in accordance with the rate of change. The invention according to claim 12 is
In the reproducing apparatus according to any one of claims 9 to 11, the second reproducing light intensity setting means operates when a predetermined time elapses after the first reproducing light intensity setting means operates. Or when the temperature change of the optical recording medium exceeds a predetermined value after the first reproducing light intensity setting means operates.

According to a thirteenth aspect of the present invention, first test writing and first test reading are performed in a plurality of areas of an optical recording medium, and irradiation is performed on the plurality of areas according to the result of the first test writing. First light intensity setting means for setting respective recording light intensities to be set, and respectively setting reproduction light intensities to be applied to a plurality of regions in accordance with the result of the first test reading; After the operation, the second test writing is performed in some of the plurality of areas, and the recording light intensity and the reproduction light set by the first light intensity setting means are set based on the result of the second test writing. Second light intensity setting means for respectively updating the light intensity, recording information on the optical recording medium with the set or updated recording light intensity, and reproducing information from the optical recording medium with the set or updated reproduction light intensity Characterized by including recording / reproducing means To.

According to a fourteenth aspect of the present invention, in the recording / reproducing apparatus according to the thirteenth aspect, the optical recording medium is an optical disk, and the plurality of areas are present at different radial positions of the optical recording medium. The first light intensity setting means sets the recording light intensity to be applied to a plurality of areas and each area of the optical recording medium other than the plurality of areas according to the result of the first test writing. The reproduction light intensity to be applied to a plurality of areas and each area of the optical recording medium other than the plurality of areas is set in accordance with the result of one test reading.

According to a fifteenth aspect of the present invention, there is provided the recording / reproducing apparatus according to the thirteenth or fourteenth aspect, wherein
In the light intensity setting means, the rate of change of the recording light intensity to be irradiated to a part of the area is obtained, and the recording light intensity set by the first recording light intensity setting means and the first reproduction light intensity setting means are determined. The set reproduction light intensity is updated to a value changed according to the change rate.

The invention according to claim 16 is the invention according to claims 13 to
16. The recording / reproducing apparatus according to claim 15, wherein the second light intensity setting means operates when a predetermined time has elapsed since the first light intensity setting means operated, or It is characterized in that the temperature change of the optical recording medium exceeds a predetermined value after the first recording light intensity setting means operates.

[0025]

Embodiments of the present invention will be described below with reference to the drawings. First, a first embodiment according to the present invention will be described with reference to FIGS. The first embodiment corresponds to claims 1 to 4 and 9 to 12. FIG. 1 is a diagram showing a main configuration of the recording / reproducing apparatus according to the first embodiment. This recording / reproducing apparatus includes an optical head 11, a laser diode driving circuit (LD driving circuit) 13, a recording waveform generating circuit 12, a reproducing circuit 16, a control unit 14, a storage unit 15, a temperature sensor 17, a magnetic field generating circuit (not shown), and the like. Prepare.

The optical head 11 mounts a laser diode, an optical system (a lens, a diffraction grating, etc.), a photodetector, and the like.
Light emitted from the laser diode at the time of recording and reproduction is condensed, and a recording or reproduction light beam is irradiated on a track of an optical disk whose rotation is controlled. Further, the optical head 11 converts the reflected light of the light beam into an electric signal corresponding to the polarization angle at the time of reproduction, and then supplies the electric signal to the reproduction circuit 16.

The reproduction circuit 16 generates reproduced data by amplifying an electric signal obtained from the optical head 11 and performing A / D conversion. The recording waveform generation circuit 12 generates a recording waveform according to a recording signal output from the control unit 14 during recording, and outputs the waveform to the LD drive circuit 13. This recording waveform is a timing waveform generated in accordance with “1” and “0” of the data bit string of the recording signal and defining the timing at which the power level of the recording light beam changes.

The LD drive circuit 13 drives the laser diode mounted on the optical head according to the timing and level indicated by the recording waveform. Specifically, the current value corresponding to each level of the recording waveform set by the control unit 14 is
It is given to the laser diode at the timing indicated by the recording waveform. During reproduction, the laser diode is constantly driven to emit continuous light.

The storage unit 15 stores a recording / reproduction control program. A program for realizing the recording / reproduction method of the first embodiment includes, for example, the procedure shown in FIG. The control unit 14 responds to an instruction from the host computer
It controls each unit based on the recording / reproducing program stored in the storage unit 15 to realize various functions of the recording / reproducing apparatus.

Regarding the control mode of the control unit 14, during recording, the relative position of the optical head 11 and the optical disk is controlled.
The exit of the optical head 11 is directly opposed to the designated area. Then, the recording signal is supplied to the recording waveform generation circuit 12, and
The current value to be supplied to the optical head 11 by the LD drive circuit 13 is set to a value for recording. During recording, a magnetic field for recording is applied to the optical disk by driving a magnetic field generation circuit (not shown).

On the other hand, at the time of reproduction, the current value to be supplied to the optical head 11 by the LD drive circuit 13 is set to a value for reproduction, so that the intensity of the light beam is set lower than at the time of recording. Then, during normal reproduction, the reproduction data obtained from the reproduction circuit 16 is corrected for errors, and the restored information is output to the host computer. When reproducing a magneto-optical disk to which the MSR technique is applied, a magnetic field generating circuit (not shown) is driven to apply a magnetic field for MSR reproduction to the magneto-optical disk.

The temperature sensor 17 is, for example, the optical disk 1
A radiation temperature sensor provided to face the surface of
At the time of recording / reproduction, the temperature of the optical disk 10 is monitored, and the monitored temperature value is given to the control unit 14. As the optical disk loaded in the reproducing apparatus, there is a magneto-optical disk 10 to which the MSR technique as shown in FIGS. 2 and 3 is applied.

As shown in the upper part of FIG. 2, the magneto-optical disk 10 has a lower protective film 50, a reproducing layer 51, a transfer layer 52, a cutting layer 55, a memory layer 53, and an upper protective film 5 on a substrate 41.
4 is formed in order. Among them, the reproducing layer 51 and the transfer layer 5
2, four layers of the cutting layer 55 and the memory layer 53 are magnetic films, and the lower protective film 50 and the upper protective film 54 are dielectric films for protecting these three layers.

The memory layer 53 is a perpendicular magnetization film having a function of recording information, and has a relatively high coercive force.
The reproduction layer 51 is a perpendicular magnetization film to which information of the memory layer 53 is transferred during reproduction, and has a relatively low coercive force.

The transfer layer 52 is in-plane magnetized at room temperature, but starts to be perpendicularly magnetized when the temperature is increased from room temperature. The cutting layer 55 is a layer for appropriately preventing transfer of information from the memory layer 53 to the reproducing layer 51, and reaches the Curie temperature at a temperature higher than the temperature at which the transfer layer 52 starts to be perpendicularly magnetized.

According to this configuration, when the light is irradiated from the substrate 41 side and a magnetic field for MSR reproduction is applied during reproduction, as shown in the lower part of FIG. It is possible to form a double mask. The magneto-optical disk 10 is provided with a test area, which is an area for performing test writing and test reading, separately from the user area. As shown in FIG.
For example, there are three test areas: a test area T1 near a radial position of 23.2 mm, a test area T2 near a radial position of 31.0 mm, and a test area T3 near a radial position of 39.5 mm.

This test area includes a test write test area and a test read test area. For example, the first half of the test area is a test write test area, and the second half is a test read test area. The assignment is fixed. A test pattern is formed in the test reading test area. In this test pattern, for example, recording marks having a length of 0.38 (μm) and non-recording portions (spaces) of 0.38 (μm) are alternately arranged, and whether or not the reproduction power is appropriate is determined. Or
Spot 33, which is the light beam irradiation surface (see the lower part of FIG. 2)
In order to reliably determine whether the size of the opening (medium temperature region 36) inside is appropriate, the length of the recording mark or the non-recording portion is equal to or less than の of the spot diameter.

Since the address signals indicating the positions of the test areas T1, T2, and T3 are recorded in advance at predetermined positions on the disk, the recording / reproducing apparatus operates with the optical head 1
1 can be moved to a position directly facing these test areas.

FIG. 4 shows a control unit 14 in the recording / reproducing apparatus.
4 is an operation flowchart of FIG. The control unit 14 performs recording and reproduction as follows. First, the magneto-optical disk 1
0 is recognized (S1 in FIG. 4), the recording power and the reproduction power are initialized (S2 to S4 in FIG. 4).
5). Thereafter, the process proceeds to the normal recording / reproducing operation (S14 in FIG. 4). When the temperature change of the magneto-optical disk 10 monitored by the temperature sensor 17 exceeds a predetermined value, the initially set recording power and reproducing power are updated ( 4S7 to S1
2).

Here, the case where the temperature of the magneto-optical disk 10 at the time of the initial setting is 25 ° C., and thereafter the temperature rises and the update is performed when the temperature change exceeds 5 ° C. It will be described as. (Initial Setting of Reproducing Power and Recording Power) In the initial setting of reproducing power, test reading is performed in all test areas T1 to T3 shown in FIG. This test reading is performed a plurality of times while changing the reproduction power.
Each time, the error rate of the reproduced signal is obtained (FIG. 4).
S2).

Next, for each test area, a range of the reproduction power in which the error rate of the reproduction signal is allowed is obtained, and the center value of the range is obtained as the optimum reproduction power for each test area. Further, based on the optimum reproducing power of each test area, the optimum reproducing power for each of zones 1 to N obtained by dividing the magneto-optical disk 10 from the inner circumference to the outer circumference by N (for example, N = 20) is obtained and stored in the storage unit 15. (S3 in FIG. 4).

The upper part of FIG. 5 (1) and FIG. 5 (3) shows the optimum reproducing power of each zone stored in this manner. The innermost zone 1 is located at a radial position of 31.0 (m).
m), the optimum reproduction power of the test areas T1, T2, and T3 is stored as it is for the zone i near the zone N and the zone N at the outermost circumference (shaded area), and the approximated values are set for the other zones. Is stored. These values are, for example, values on the curve (a) passing through the values of the optimum reproduction powers of the test areas T1, T2, T3, as shown in FIG.

The initial setting of the recording power is performed in substantially the same manner. That is, test writing is performed in all of the test areas T1 to T3 shown in FIG. This test writing is performed a plurality of times while changing the recording power, and the error rate of the reproduced signal is obtained for each test area and each time (FIG. 4S
4). In this trial writing, reference information which is predetermined information is recorded. At this time, the recording light beam is modulated in the same manner as in ordinary recording, and shows, for example, any of the waveforms in FIGS. Incidentally, the waveforms shown in FIG. 6 (2) and thereafter are intended to adjust the shape of the recording mark formed on the optical disk 10, and the high power level PH at which the data "1" is written or the data "0" is set. The low power level PL to be written is further finely modulated.

Next, for each test area, a range of the recording power such that the error rate of the reproduction signal is an allowable value is obtained, and the center value of the range is obtained as the optimum recording power. Further, from the optimum recording power of each test area, the optimum recording power for each of the zones 1 to N obtained by dividing the inner surface from the inner periphery to the outer periphery of the magneto-optical disk 10 is obtained and stored in the storage unit 15 (S5 in FIG. 4).

The upper part of FIG. 5A and FIG. 5B shows the optimum recording power of each zone stored in this manner. The innermost zone 1 has a radial position of 31.0 (m).
m), the optimum recording power of each of the test areas T1, T2, and T3 is stored as it is for the zone i near the outermost zone N and the zone N at the outermost circumference (shaded area), and the approximated values are set for the other zones. Is stored. These values are, for example, values on the curve (b) passing through the optimum recording power values of the test areas T1, T2, and T3, as shown in FIG.

That is, in the initial setting, the optimum reproduction power and the optimum recording power are set to the zone 1, the zone i and the zone N
Is actually measured, and the other zones are obtained by calculation from the result of the measurement. (Update of reproduction power and recording power) On the other hand, when updating the set values, the measurement of the optimum reproduction power and the optimum recording power is not performed in a single zone.

For example, the optimum reproducing power of the zone 1 is obtained by using the test area T1 (S7 in FIG. 4). When the test reading was performed while changing the reproducing power in the same manner as the initial setting, as shown by the lower hatched portion in FIG. 5C, the optimum reproducing power of the zone 1 which was 2.50 (mW) in the initial setting was Suppose that it turned out that it changed to 2.45 (mW).

That is, the change rate α of the optimum reproducing power of the zone 1 is obtained by the equation α = 2.45 / 2.50 ≒ 98.0% (S8 in FIG. 4). In the first embodiment, it is assumed that the optimum recording powers of the other zones except the zone 1 have changed by the same rate as the change rate α. That is, the change rate α is multiplied by the initially set optimum reproduction power (the upper part of FIG. 5C), and the obtained product is updated as the optimum reproduction power of all the zones (S9 in FIG. 4).

The value updated for each zone as described above is
As shown in the lower part of FIG. 4 (3), they are arranged on the curve (c) of FIG. 5 (1). That is, the optimum reproduction power of all the zones is updated with the rate of change of the optimum reproduction power obtained by measurement in a single zone, while keeping the tendency of the optimum reproduction power obtained at the time of initial setting depending on the radial position.

The updating of the recording power is performed in the same manner. That is, test writing is performed only in the test area T2 (S1 in FIG. 4).
0), and the change rate β of the optimum recording power in the zone 1 is obtained (S11 in FIG. 4).

Incidentally, in FIG. 5 (2), the change rate β
Is β = 6.00 / 6.10 ≒ 98.4%. Next, the change rate β is multiplied by the initially set optimum recording power (the upper part of FIG. 4 (2)) to update the optimum recording power of all zones (FIG. 4S12) (the lower part of FIG. 4 (2),
FIG. 4 (1) (d)).

That is, the optimum recording power of all the zones is updated at the rate of change of the optimum recording power obtained by measurement in a single zone, while keeping the tendency of the optimum recording power determined by the radial position at the time of initial setting. . In short, in the first embodiment, when updating each set value, test writing and test reading are performed only in a single test area, and the update is completed in a shorter time than the initial setting. In addition, since the tendency of the power depending on the radial position is obtained at the time of the initial setting, the optimum recording power and the optimum reproducing power of all the zones can be surely updated while keeping the tendency.

Therefore, the processing time for updating the optimum recording power and the optimum reproducing power can be shortened without lowering the performance of the apparatus, and the reduction in the data transfer rate of the apparatus can be suppressed. In addition, regarding the correspondence between the claims and the first embodiment described above, the first reproduction light intensity setting means, the second reproduction light intensity setting means, the reproduction means, and the recording / reproduction means are mainly controlled. The unit 14 corresponds. Steps 2 and 3 of the control unit 14 correspond to the first reproduction light intensity setting procedure, and step 7 and step 7 of the control unit 14 correspond to the second reproduction light intensity setting procedure.
8 and 9 correspond to each other.
4 corresponds.

Next, a second embodiment according to the present invention will be described with reference to FIGS. The second embodiment corresponds to claims 5 to 8 and 13 to 16. Here, only differences from the first embodiment will be described, and description of the other portions will be omitted. FIG. 9 is an operation flowchart of the control unit 14 in the second embodiment. In the second embodiment, the initial settings (S2 to S5 in FIGS. 9A to 9C) are performed in the same manner as in the first embodiment, and the recording power and the reproduction power set as a result are shown in the upper part of FIGS. It is shown.

At the time of updating, first, test writing is performed in the test area T1 (S10 in FIG. 9), and a change rate β of the optimum recording power of the zone 1 is obtained (S11 in FIG. 9). Incidentally, FIG.
In (2), the rate of change β is β = 6.00 / 6.10.
It is 98.4%. Next, in step 20 of FIG. 9, the change rate β is multiplied by the initially set optimum recording power (the upper part of FIG. 10B) to update the optimum recording power of all zones (FIG. 10B). Lower part, FIG.
(1) (d)).

In the second embodiment, it is assumed that the optimum reproducing power also changes by the same amount as the change rate β of the optimum recording power. That is, the change rate β is multiplied by the initially set optimum reproduction power (the upper part of FIG. 10 (3)) to update the optimum reproduction power of all the zones (the lower part of FIG. 10 (3),
FIG. 10 (1) (c)).

In short, in the second embodiment, the update value of the reproduction power is obtained by calculation without performing test reading at the time of updating each set value. Therefore, the update is completed in a shorter time than in the first embodiment. That is, a decrease in the data transfer rate of the device can be further suppressed. Here, as is clear from FIG. 10A, since the absolute value of the optimum recording power is larger than that of the optimum reproducing power, the rate of change of the actually measured optimum recording power is:
Required relatively accurately. Then, even if the value of the rate of change is used as it is for the optimum reproduction power, it can be updated with desired accuracy.

The reproduction power at the time when steps 10 and 11 in FIG. 9 are executed should be set to a value before a predetermined temperature change occurs in the magneto-optical disk 10. Therefore, the reading for obtaining the result of the test writing is performed with the old reproduction power before such update, that is, the power deviated from the optimum reproduction power.

Therefore, in the second embodiment, even if the optimum reproducing power is deviated by a predetermined temperature change, the deviation is at most within a range in which the information can be read in order to surely perform the reading. It is assumed that it is within the range. In addition, the claim and the second
In terms of correspondence with the embodiment, the control unit 14 mainly corresponds to the first light intensity setting means, the second light intensity setting means, and the recording / reproducing means. Steps 2, 3, 4, and 5 of the control unit 14 correspond to the first light intensity setting procedure.
Step 10 of the control unit 14 includes the second light intensity setting procedure.
11 and 20 correspond to each other, and step 14 of the control unit 14 corresponds to the recording / reproducing procedure.

In the second embodiment, the rate of change of the optimum recording power (recording sensitivity) and the rate of change of the optimum reproduction power (reproduction power) under the same environmental change are regarded as the same. Not limited. For example, if the difference between the recording sensitivity and the reproduction sensitivity, which is affected by environmental changes, is taken into consideration, the recording sensitivity change rate and the reproduction sensitivity change rate are measured in advance for a certain magneto-optical disk, and the Correction corresponding to the difference may be performed.

In each of the above embodiments, the recording power and the reproducing power are updated when the temperature change reaches a predetermined value. However, similar updating may be performed at regular time intervals. In this case, a timer is provided instead of the temperature sensor 17. In each of the above embodiments,
The sensitivity change rate according to the environmental temperature is considered to be uniform on the magneto-optical disk, and the optimum power of all zones is changed at the same change rate as the optimum power of the predetermined zone, but is not limited to this. . For example, if it is considered that there is a difference in the way of being affected by environmental changes depending on the position on the magneto-optical disk, the sensitivity change rate of each zone is measured in advance, and the deviation of the sensitivity change rate upon updating is determined. A corresponding correction may be made.

Further, in order to adapt to the tendency of the recording sensitivity and the reproduction sensitivity depending on the radial position due to the environmental change, when each set value is updated, test writing or test reading is performed in two test areas, and each time the radius is changed. The tendency according to the position may be roughly obtained. Also in this case, the effect is obtained because the updating process is shorter than at the time of the initial setting.

In each of the above embodiments, the error rate of the reproduced signal is measured by the trial reading and the trial writing. However, the amplitude of the reproduced signal may be measured, and the superiority of the reproduced signal may be determined based on the amplitude. . In each of the above embodiments, an example of recording / reproducing of the magneto-optical disk 10 to which the MSR technique is applied is given. However, a direct overwrite method in which accuracy required for recording power is relatively strict is applied. Even if the present invention is applied to recording / reproducing of a magneto-optical disk, the recording power can be updated with desired accuracy. Further, the present invention may be applied to any optical disk that requires setting of recording power and reproducing power. Further, the shape of the optical recording medium may be a shape other than a disk.

[0064]

As described above, according to the first aspect of the present invention, since the number of times of trial reading is reduced, the processing time of the second reproduction light intensity setting procedure is longer than that of the first reproduction light intensity setting procedure. Can be shortened. The second aspect of the present invention relates to the reproduction of an optical disk. Even if the temperature distribution generated by the reproduction light differs depending on the radial position of the optical disk, the intensity of the reproduction light to be applied to each area of the optical disk can be set.

According to the third aspect of the present invention, it is possible to update the reproduction light intensity to irradiate a plurality of regions by a predetermined calculation based on the change rate of the reproduction light intensity to irradiate some regions. According to the fourth aspect of the invention, appropriate reproduction can always be performed by following the reproduction sensitivity of the optical recording medium regardless of environmental changes.

According to the fifth aspect of the present invention, since the number of trial writings is reduced and the trial reading is omitted,
The processing time of the second light intensity setting procedure can be shorter than that of the first light intensity setting procedure. The invention according to claim 6 relates to recording / reproduction of an optical disk, and even if the temperature distribution generated by the recording light and the reproduction light differs depending on the radial position of the optical disk, the recording light intensity to be irradiated to each area of the optical disk and The reproduction light intensity can be set individually.

According to the seventh aspect of the present invention, the recording light intensity and the reproduction light intensity to be applied to a plurality of areas are updated by a predetermined calculation based on the change rate of the recording light intensity to be applied to some areas. be able to. According to the eighth aspect of the invention, it is possible to always perform appropriate recording and reproduction by following the recording sensitivity and the reproduction sensitivity of the optical recording medium irrespective of environmental changes.

According to the ninth to sixteenth aspects of the present invention, an apparatus for realizing the first to eighth aspects can be provided. Further, it is possible to suppress a decrease in the performance of the apparatus due to the setting of the reproducing light intensity and the recording high intensity.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a main configuration of a recording / reproducing apparatus.

FIG. 2 is a conceptual diagram of the magneto-optical disk 10.

FIG. 3 is a diagram showing a test area of the magneto-optical disk 10.

FIG. 4 is an operation flowchart of a control unit 14 according to the first embodiment.

FIG. 5 is a diagram illustrating a first embodiment.

FIG. 6 is a diagram showing a temporal change in power of a recording light beam.

FIG. 7 is a diagram showing a temporal change in power of a recording light beam.

FIG. 8 is a diagram showing a temporal change in power of a recording light beam.

FIG. 9 is an operation flowchart of a control unit 14 according to the second embodiment.

FIG. 10 is a diagram illustrating a second embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Optical head 12 Recording waveform generation circuit 13 Laser diode drive circuit (LD drive circuit) 14 Control part 15 Storage part 17 Temperature sensor 10 Magneto-optical disk 31 Track 33 Spot 34 Heat storage area 35 High temperature area 36 Medium temperature area 37 Low temperature area 38 Recording mark 41 Substrate 50 Lower protective film 51 Reproducing layer 52 Transfer layer 53 Memory layer 54 Upper protective film 55 Cutting layer T1, T2, T3 Test area

Claims (16)

[Claims] A first test reading is performed in a plurality of areas of an optical recording medium, and a reproduction light intensity to be applied to the plurality of areas is set in accordance with a result of the first test reading. After executing the reproduction light intensity setting procedure and the first reproduction light intensity setting procedure, a second test reading is performed in a part of the plurality of areas, and based on a result of the second test reading. A second reproducing light intensity setting procedure for updating the reproducing light intensity set by the first reproducing light intensity setting procedure, and information from the optical recording medium with the setting or the updated reproducing light intensity. A reproducing procedure for reproducing. 2. The reproduction method according to claim 1, wherein the optical recording medium is an optical disk, the plurality of areas are present at different radial positions on the optical recording medium, and the first reproduction light intensity is In the setting procedure, the reproduction light intensity to be applied to the plurality of areas and each area of the optical recording medium other than the plurality of areas is set according to a result of the first test reading. And the reproduction method. 3. The reproducing method according to claim 1, wherein in the second reproducing light intensity setting step, a change rate of the reproducing light intensity to be applied to the partial area is obtained, and A reproducing method characterized in that the reproducing light intensity set in the reproducing light intensity setting procedure of 1 is updated to a value changed according to the change rate. 4. The reproducing method according to claim 1, wherein the second reproducing light intensity setting step is performed, wherein the first reproducing light intensity setting step is performed by the first reproducing light intensity setting step. A reproducing method, wherein a predetermined time has elapsed after the execution, or a temperature change of the optical recording medium has exceeded a predetermined value since the first reproducing light intensity setting procedure was performed. 5. A first test writing and a first test reading are performed in a plurality of areas of an optical recording medium, and a recording light intensity to be applied to the plurality of areas is determined according to a result of the first test writing. A first light intensity setting procedure for setting the respective reproduction light intensities to be applied to the plurality of regions in accordance with a result of the first test reading; and after executing the first light intensity setting procedure. A second test writing is performed in a part of the plurality of areas, and the recording light intensity and the reproduction light set in the first light intensity setting procedure are set based on the result of the second test writing. A second light intensity setting procedure for respectively updating the intensity, and recording information on the optical recording medium at the setting or the updated recording light intensity, and the optical recording medium at the setting or the updated reproduction light intensity. Record / reproduce information from Recording and reproducing method characterized by comprising the steps. 6. The recording / reproducing method according to claim 5, wherein the optical recording medium is an optical disk, the plurality of areas are present at different radial positions on the optical recording medium, and In the intensity setting procedure, according to the result of the first test writing, the plurality of areas and the recording light intensity to be applied to each area of the optical recording medium other than the plurality of areas are respectively set, and According to a result of the first test reading, a reproducing light intensity to be applied to the plurality of areas and each area of the optical recording medium other than the plurality of areas is set.
Playback method. 7. The recording / recording method according to claim 5 or claim 6.
In the reproducing method, in the second light intensity setting procedure, a change rate of the recording light intensity to be applied to the partial area is obtained, and the recording light intensity set in the first recording light intensity setting procedure; A recording / reproducing method, wherein the reproducing light intensity set in the first reproducing light intensity setting procedure is updated to a value changed according to the change rate. 8. The recording / reproducing method according to claim 5, wherein the second light intensity setting procedure is executed when the first light intensity setting procedure is performed. Recording / reproduction when a predetermined time has elapsed after the execution, or when a temperature change of the optical recording medium has exceeded a predetermined value since the first recording light intensity setting procedure was executed. Method. 9. A first test reading in a plurality of areas of an optical recording medium, and setting a reproduction light intensity to be applied to the plurality of areas in accordance with a result of the first test reading. After the operation of the reproduction light intensity setting means and the first reproduction light intensity setting means, a second test reading is performed in some of the plurality of areas, and based on a result of the second test reading. Second reproduction light intensity setting means for respectively updating the reproduction light intensity set by the first reproduction light intensity setting means; and information from the optical recording medium with the setting or the updated reproduction light intensity. A reproducing apparatus, comprising: reproducing means for reproducing. 10. The reproducing apparatus according to claim 9, wherein the optical recording medium is an optical disk, the plurality of areas exist at different radial positions on the optical recording medium, and the first reproduction light intensity is The setting means sets, in accordance with a result of the first test reading, a reproduction light intensity to be applied to the plurality of areas and each area of the optical recording medium other than the plurality of areas. Playback device. 11. The reproducing apparatus according to claim 9, wherein the second reproducing light intensity setting means obtains a change rate of the reproducing light intensity to be applied to the partial area, and A reproducing apparatus, wherein the reproducing light intensity set by the first reproducing light intensity setting means is updated to a value changed according to the rate of change. 12. The reproducing apparatus according to claim 9, wherein the second reproducing light intensity setting means operates, wherein the first reproducing light intensity setting means operates. A reproducing apparatus, wherein a predetermined time has elapsed since the start of the operation, or when a change in the temperature of the optical recording medium has exceeded a predetermined value since the operation of the first reproducing light intensity setting means. 13. A method according to claim 1, wherein a plurality of first areas are provided in a plurality of areas of the optical recording medium.
And the first test reading is performed, and the recording light intensities to be applied to the plurality of areas are respectively set according to the result of the first test writing, and the recording light intensity is set according to the result of the first test reading. First light intensity setting means for setting the reproduction light intensity to be applied to the plurality of areas, respectively, and after the operation of the first light intensity setting means, a second light intensity is set in some of the plurality of areas. Second light intensity setting means for performing test writing and updating the recording light intensity and the reproduction light intensity set by the first light intensity setting means based on the result of the second test writing; Recording / reproducing means for recording information on the optical recording medium at the set or updated recording light intensity and reproducing information from the optical recording medium at the set or updated reproduction light intensity. Recording / reproducing device. 14. The recording / reproducing apparatus according to claim 13, wherein the optical recording medium is an optical disk, the plurality of areas are present at different radial positions on the optical recording medium, In the intensity setting means, according to the result of the first test writing, the plurality of areas and the recording light intensity to be applied to each area of the optical recording medium other than the plurality of areas are set, and According to a result of the first test reading, a reproducing light intensity to be applied to the plurality of areas and each area of the optical recording medium other than the plurality of areas is set.
Playback device. 15. The recording / reproducing apparatus according to claim 13, wherein the second light intensity setting means obtains a change rate of recording light intensity to be applied to the partial area, Updating the recording light intensity set by the first recording light intensity setting means and the reproduction light intensity set by the first reproduction light intensity setting means to a value changed according to the change rate. Recording / reproducing apparatus characterized by the above-mentioned. 16. The recording / reproducing apparatus according to claim 13, wherein the second light intensity setting means operates, wherein the first light intensity setting means operates. A recording / reproducing apparatus, wherein when a predetermined time has elapsed since the start of the operation, or when a change in temperature of the optical recording medium has exceeded a predetermined value after the first recording light intensity setting means has been operated. .