JP2001184792A - Optical disk recording/reproducing device and optical disk - Google Patents

Abstract

PROBLEM TO BE SOLVED: To correct the waveform of a recording signal without necessitating special time. SOLUTION: The waveform of the recording signal of data is corrected by using free time of pickup 24 to be generated in the case of writing or reading of the data in a temporary storage memory 28 by a waveform correcting circuit 60. The pickup 24 is first moved to a test recording area of an optical disk 22, switching it to a test pattern generating circuit 64 by a switching circuit 62 and a test pattern signal is recorded in the optical disk 22. And the recorded test signal is reproduced, its jitter is measured and a method for correcting the waveform in the waveform correcting circuit 60 is changed so that a measured value is reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical disk recording / reproducing apparatus provided with data temporary storage means, and a multi-layered optical disk capable of recording / reproducing with the optical disk recording / reproducing apparatus. It relates to a preferable correction of a recording waveform.

[0002]

2. Description of the Related Art In a conventional optical disk device, for example, an MD, at the time of reproduction, a reproduction time of about 10 seconds is required.
The data is temporarily stored in the shock proof memory of the MB (bit), and the pickup kicks the track while the signal is being reproduced from the shock proof memory, so that the rotation waiting for the next sector to be reproduced is performed. ing. Also, during recording, the recording signal is compressed and temporarily stored in a shock-proof memory, the signal is intermittently read out from this memory and recorded on an optical disk, and the pickup kicks the track for the remaining time. Is waiting for rotation for the sector to be recorded next. In addition, the DVD player also
It has a 6MB memory and has a variable transfer rate and a high transfer rate. This memory has a storage time of about 2 seconds, and similarly, the pickup kicks the truck and waits for rotation.

[0003] At present, it is difficult to obtain a 4 MB DRAM, and it is becoming common to use a 16 Mbit DRAM or more. For this reason, temporary storage for two seconds or more is becoming possible.

Meanwhile, a technique for reproducing and recording high-density information using a laser beam is known, and has been put to practical use mainly as an optical disk device. Optical disks can be broadly classified into a read-only type, a write-once type, and a rewritable type. The read-only type is a CD that stores music information or a V that stores image information.
CD or DVD, and write-once type is CD-R or DVD-
Each is commercialized as R. In addition, CD-RW, DVD-RAM, DVD-RW, and the like are being commercialized as rewritable types for recording video and audio, or for recording data for personal computers.

[0005] Of these, the rewritable type uses a recording layer in which two or more states change reversibly by changing the irradiation conditions such as laser light, and the main one is a magneto-optical type. There are variations. Phase-change optical disks record signals by changing the recording layer reversibly between amorphous and crystalline by changing the irradiation conditions of laser light, and optically determine the difference in the laser light reflectance between amorphous and crystalline. The reproduction is performed upon detection. The point that the signal can be reproduced as such a change in the reflectance of the laser beam is the same as that of the read-only type or the write-once type. ) Can be performed with one beam, so that there is an advantage that the device configuration can be simplified.

As a method of increasing the density of signal recording on such a rewritable optical disk, a pulse width modulation method (PWM) in which the edge positions before and after a recording mark correspond to "1" of a digital signal has been studied. I have.

[0007]

By the way, in the PWM method, since the width of the recording mark has information, it is necessary to record the recording mark on the recording layer without distortion, that is, symmetrically in the front-back direction. However, the laser irradiation portion of the optical disk at the time of recording a signal has a higher temperature at the end point than at the irradiation start point due to the heat storage effect. For this reason, the width of the recording mark is wider at the end than at the tip, and there is a disadvantage that the shape of the recording mark is narrow at the tip and thick at the end and is distorted like teardrops.

The cause of such a recording mark being distorted like teardrops will be further described below with reference to the drawings. FIG. 15 (A)
Is an input signal waveform to be recorded. When this is directly converted into a laser beam output as it is as shown in FIG. 3B and a signal is recorded by modulating between the erasing power level Pe and the recording power level Pw, the ultimate temperature of the recording layer becomes as shown in FIG. become that way. That is, due to the heat storage effect, the temperature of the end portion of the recording mark becomes higher than that of the tip portion, and as a result, the shape of the recording mark becomes wider at the end portion than at the tip end as shown in FIG. Distorted in shape. Since the heat storage effect increases as the relative speed (linear speed) between the optical disk and the laser spot decreases, the tear tree-like distortion also increases as the linear speed decreases. Since this distortion causes distortion of the reproduced waveform, there is a possibility that the recorded signal cannot be read correctly.

As a method for reducing the distortion of such recording marks, Japanese Patent Laid-Open Publication No. Hei 3-185628 discloses an overwrite method in which one recording mark is formed by irradiating a plurality of short pulse trains. In addition, JP-A-6-
Japanese Patent Publication No. 12674 discloses a method of correcting the pulse waveform. Referring to FIG. 16, after converting an input signal as shown in FIG. 16A into a short pulse train,
The laser output is erased at the power level Pe as shown in FIG.
The signal is overwritten by modulating between the signal and the recording power level Pw. Here, the short pulse train is composed of a head pulse having a wide width and a subsequent pulse train having a narrower width. The width of the first pulse is always constant regardless of the length of the recording mark. Further, the width and interval of each pulse in the subsequent pulse train are equal, and the number of pulses in the subsequent pulse when forming the n-th recording mark is n-1.

[0010] For example, an 8-14 modulation signal (EFM signal) used in a CD is composed of 9 types of pulses from 3T (T is a clock cycle) to 11T.
When recording this EFM signal, the shortest 3T pulse is converted into only the first pulse, the next 4T pulse is converted into the first pulse and one subsequent pulse, and the 5T pulse is converted into the first pulse and two subsequent pulses. I do. The longest 11T
Are converted into a first pulse and eight subsequent pulses. By performing conversion with such regularity, the signal conversion circuit can have a simple configuration. In this case, the temperature reached by the recording layer sharply rises at the leading end by a wide leading pulse as shown in FIG. 4C, but thereafter, the pulse train is irradiated, so that the rising end temperature is suppressed. . As a result, the shape of the recording mark is improved in symmetry between the leading end and the trailing end, as shown in FIG.

However, the above-described technique of shortening the pulse is very effective when the linear velocity is low and the recording frequency is low. However, in the case of high-density recording such as a DVD-RAM or DVD-RW, the linear velocity is low. Is not always effective when the recording signal is fast or when the frequency of the recording signal is high. When the recording signal waveform is shortened, the energy applied to the recording layer is reduced, so that a large recording power is required. This is not a problem at low linear velocities,
If the linear velocity becomes faster and a larger recording power is required, a high-power laser light source is required, and the cost of the recording apparatus is increased. Further, in order to shorten the pulse of the input signal, a clock signal having a period that is an integer fraction of the pulse period of the input signal (T in the case of the EFM signal) is necessary, and the frequency of the recording signal is high. In such a case, the frequency of the clock signal becomes too high and circuit design becomes difficult. The more the laser output is modulated at a higher frequency, the greater the waveform distortion.

Considering a general method of using an optical disc, when the optical disc is rotated at a constant rotation speed (hereinafter referred to as CAV), the outer periphery has a higher linear velocity than the inner periphery. In order to increase the recording density by making the recording mark length the same on the inner and outer circumferences, a method of increasing the recording frequency on the outer circumference has also been proposed. Even when the optical disk is rotated at a constant linear velocity in all areas (hereinafter referred to as CLV), when recording signals on different types of optical disks with the same recording device, the linear velocity and the recording frequency are changed depending on the type of optical disk. There is a need.

In addition, in the case of an optical disc having a higher recording density, the reproduction quality may be degraded due to variations in the individual optical discs, the number of recordings of the optical disc, or environmental conditions such as the ambient temperature and the like, and the optimum recording conditions differ. There is. Further, in order to determine the optimum recording condition for each optical disk, it is necessary to perform test recording, reproduce the signal, measure the signal quality, and search for the optimum value. However, it takes too much time to perform such a measurement at the time of recording, and there is a disadvantage that a signal to be originally recorded cannot be recorded from the beginning. In particular, in the case of a multilayer optical disc in which the recording layer is stacked in the thickness direction of the optical disc, it takes much more time to perform such a measurement at the time of recording, and a signal to be originally recorded is recorded on the designated recording layer from the beginning. There are inconveniences such as not being able to record in

[0014]

In order to solve the above-mentioned problems, the present invention provides an optical disk recording / reproducing apparatus and an optical disk having the following constitutions (1) to (15). (1) A recording laser beam obtained by optically modulating input data to be recorded on a recording layer of a multi-layer optical disc having at least one recording layer that changes phase reversibly optically with pulse width modulated recording data. Forming a mark by irradiating the mark, irradiating a reproduction laser beam on the mark to reproduce the recorded data, and writing the input data until a first storage amount is reached, and writing the input data. Temporary storage means for reading input data at a read speed different from the write speed until reaching a second storage amount lower than the first storage amount, and supplying the read data to the optical pickup means; An optical pickup control means for performing focus jump control on the optical pickup means so as to focus and irradiate a recording laser light or a reproduction laser light, During the period in which the input data is written to the temporary storage unit and during which the optical pickup unit does not perform the recording, reproduction, and seek operations, a recording test is performed on the recording layer, A waveform correction means for storing a waveform correction value for correcting the pulse waveform of the recording data on the device side and / or the multi-layer optical disc side based on the test result;
An optical disk recording / reproducing apparatus, wherein the waveform correction of the recording data is performed using the waveform correction value. (2) A recording laser beam obtained by optically modulating input data to be recorded on a recording layer of a multi-layer optical disc having at least one recording layer that changes phase reversibly optically with pulse width modulated recording data. Forming a mark by irradiating the mark, irradiating a reproduction laser beam on the mark to reproduce the recorded data, and writing the input data until a first storage amount is reached, and writing the input data. Temporary storage means for reading input data at a read speed different from the write speed until reaching a second storage amount lower than the first storage amount, and supplying the read data to the optical pickup means; An optical pickup control means for performing focus jump control on the optical pickup means so as to focus and irradiate a recording laser light or a reproduction laser light, A recording test is performed on the recording layer during a period during which the input data is read from the temporary storage unit and during an idle time during which the optical pickup unit does not perform recording, reproduction, and seek operations. ,
Waveform correction means for storing a waveform correction value for correcting the pulse waveform of the recording data on the device side and / or the multi-layer optical disc side based on the test result, and when recording, the recording is performed using the waveform correction value. An optical disc recording / reproducing apparatus for performing data waveform correction. (3) The optical disc recording / reproducing apparatus according to claim 1 or 2, wherein disc-specific identification information read from the multilayer optical disc is recorded together with the waveform correction value. (4) The optical disc recording / reproducing apparatus according to claim 3, wherein the disc unique identification information and the waveform correction value are reproduced. (5) The test signal used in the recording test includes a predetermined number of repetitive signals of a specific signal sequence that shows a tendency for jitter to deteriorate when the test signal is recorded and reproduced. An optical disk recording / reproducing apparatus according to any one of claims 1 to 4. (6) The repetition of the specific signal sequence of the test signal is as follows:
6. The optical disc recording / reproducing apparatus according to claim 5, wherein the recording / reproducing apparatus includes at least a shortest wavelength among recording wavelengths. (7) The means for evaluating the quality of the waveform correction value includes a measuring means for measuring a jitter value of a signal reproduced from the waveform correction value, and determining whether the jitter value measured by the measuring means is within a predetermined value. Determining means; and if the determination result determined by the determining means is within the predetermined value, the recording parameter setting means for storing the test signal so that the recording parameter is used at the time of recording the test signal; And a quality re-evaluating means for re-evaluating the quality of the test signal by changing a recording parameter when the result of the determination is out of the predetermined value. Item 8. An optical disk recording / reproducing apparatus according to any one of Items 7. (8) Coefficient means for counting the number of quality re-evaluations performed by the quality re-evaluation means, and prohibition of writing the test signal when the count value of the coefficient means exceeds a prescribed value. The optical disk recording / reproducing apparatus according to claim 7, further comprising means. (9) Temperature measuring means for measuring a reference temperature on the device side when the optimum waveform correction value is obtained, and the waveform correction value is calculated according to a temperature change from the reference temperature measured by the temperature measuring means. 9. The optical disk recording / reproducing apparatus according to claim 1, further comprising a temperature changing unit for changing the temperature. (10) It is further provided with a recording number management means for managing the number of recordings in which the recording data is overwritten, and a number changing means for changing the waveform correction value in accordance with the number of recordings counted by the recording number management means. The optical disk recording / reproducing apparatus according to any one of claims 1 to 9, wherein: (11) The optical disc recording / reproducing apparatus according to any one of claims 1 to 10, wherein the recording layer on which the recording test is performed is a layer different from a layer on which recording or reproduction is currently performed. (12) The recording area of the recording layer on which the recording test is performed is:
The optical disk recording / reproducing apparatus according to any one of claims 1 to 10, wherein the optical disk recording / reproducing apparatus is a free area closest to an area where recording or reproduction is currently performed. (13) The recording area of the recording layer on which the recording test is performed is:
The optical disk according to any one of claims 1 to 10, wherein the optical disk is a free area closest to an area where recording or reproduction is currently performed and a layer different from a layer where recording or reproduction is currently performed. Recording and playback device. (14) A multilayer optical disc having at least one recording layer which is recordable / reproducible by the optical disc recording / reproducing apparatus according to any one of claims 1 to 13 and has an optically reversible phase change. An optical disc, comprising: a test recording area for recording a waveform correction value for correcting a pulse waveform of the recording data based on a result of a recording test performed on a recording layer. (15) The optical disc according to claim 14, wherein the test recording area is provided in a lead-in area, and records the waveform correction values of all the recording layers.

Specifically, TB (track buffer)
In an optical disc recording / reproducing apparatus loaded with an optical disc having a multilayer structure, for example, a two-layer structure, while recording or reproducing a predetermined recording layer, other recording layers are also being recorded on the TB. A test is performed during or during storage during reproduction to determine an optimum value for recording. Further, this value is recorded on the optical disk or the apparatus, and at the time of restart, it is detected whether or not the test should be performed by looking at this value, and if there is this data, recording is performed based on this value. In addition, the test recording can be omitted by referring to the correction value of the optical disk or the device for the second and subsequent times. In addition, this test is performed using a free time other than recording and reproduction. Further, the method of correcting the waveform is changed according to a change in the relative speed between the optical disk and the laser spot. Still further, the method of correcting the waveform is changed in accordance with a change in a measurement result of a measurement sensor such as an ambient temperature of the optical disk or the apparatus. Furthermore, the test recording area is the free area closest to the area currently being recorded or reproduced, and does not require much time such as movement. According to the present invention, pulse width modulation is performed by a practical device configuration on an area of an optical disk having different linear velocities such as individual optical disk variations and temperature changes, or on different types of optical disks used at different rotational speeds. Digital signals can always be recorded with small recording mark distortion, reproduction waveform distortion is reduced, high-density recording is possible, and no adjustment is required for the user even when using a multilayer optical disc Recording can be performed promptly without requiring time and without giving a sense of incongruity.

[0016]

Embodiments of the present invention will be described below in detail. In the following description, an optical disc having a two-layered recording layer will be described as an example of a multi-layered optical disc having at least one recording layer that changes optically and reversibly by irradiation with a recording laser beam. In the present embodiment, the recording laser waveform is corrected to an optimum shape according to the type of the optical disk and changes in the linear velocity. For example, when the input signal (for example, the EFM signal) is as shown in FIG. 1A, and when the linear velocity is lower than a preset value,
The laser modulation waveform is a recording waveform WA that is made into a short pulse train as shown in FIG. When the linear velocity is higher than the set value, the laser modulation waveform is converted into a recording waveform WB having a slightly shorter input pulse width as shown in FIG.

Next, a specific example will be described. At first,
Recording and reproduction are performed on one phase-change optical disk while changing the linear velocity and the recording waveform variously, and the relationship between the linear velocity and the reproduced waveform distortion is obtained. As shown in FIG. 2, the structure of the optical disk used in the experiment was that a dielectric film 2, a recording layer 3,
A dielectric film 4, a semi-transmissive film 5, a dielectric film 6, a recording layer 7, a dielectric film 8, and a reflective film 9 are sequentially laminated. Recording and reproducing laser light enters from the substrate 1 side. The substrate 1 is made of polycarbonate and has a diameter of 200
mm disk. The recording layers 3 and 7 are made of three elements GeSbTe, and have a thickness of 20 nm. The dielectric films 2, 4, 6, 8 above and below the recording layers 3, 7 are made of ZnS, the dielectric films 2, 6 on the substrate side are 150 nm, and the dielectric films 4, 8 on the opposite side are 15 nm. As the reflection film 9, A
u is provided at 50 nm. The semi-transmissive film 5 has such a light transmittance that the recording and reproducing laser light incident from the substrate 1 reaches the recording layer 7 and obtains good recording and reproducing characteristics.

After the entire recording layers 3 and 7 of such an optical disk are crystallized in advance (the signal is erased), signals are recorded as amorphous recording marks by laser irradiation. Four linear velocities of 1.5 m / s, 3 m / s, 6 m / s, and 9 m / s were selected by changing the number of rotations of the optical disk. An EFM signal was used as an input signal. Then, the semiconductor laser is set to (1) recording waveform W
A signal was recorded by driving in a method of correcting and modulating the pulse train into a short pulse train as shown in A, and (2) a method of modulating the pulse train in a slightly shorter manner as shown in a recording waveform WB.

FIG. 3 shows a specific recording waveform shape. First, FIG. 1A shows an example of an input waveform of an EFM signal, where T is a clock cycle. FIG. 3B shows the recording waveform WA. In this case, the width Ta until the pulse is generated is 1
T, the width of the first pulse in the short pulse train is Tb = 1.5T,
The width Td and interval Tc of the subsequent pulse were both 0.5T. That is, the clock cycle of the recording waveform WA is 0.5T, and a clock having a frequency twice as high as that of the EFM signal is required. FIG. 3C shows a recording waveform WB. In this case, the width of all the recording pulses is shorter than the EFM signal by T.

The clock frequency of the EFM signal was changed so that the recording mark length would be the same even if the linear velocity changed. Specifically, when the linear velocity is 1.5 m / s, the clock frequency is 4.3 MHz, when the linear velocity is 3 m / s, the clock frequency is 8.6 MHz, and when the linear velocity is 6 m / s, the clock frequency is 17. When the frequency is 2 MHz and the linear velocity is 9 m / s, the clock frequency is 25.8 MHz.

Next, the signal recorded as described above is reproduced, and the magnitude of the distortion of the reproduced waveform is obtained. The quantitative evaluation of the reproduced waveform distortion is performed by binarizing the reproduced waveform in advance and then inputting the binarized data to a time interval analyzer to determine the amount of jitter as a phase margin. The larger the phase margin, the smaller the amount of shift between the edge positions before and after the recording mark, and the smaller the distortion of the recording mark. FIG. 4 shows the relationship between the phase margin and the variation in linear velocity in several types of optical disks. When the linear velocity was 9 m / s, the recording waveform was B. FIG. 5 shows the relationship between the phase margin and the variation in the linear velocity with respect to the temperature change of the optical disk. FIG. 6 shows the relationship between the recording power and the linear velocity on the surface of the optical disk at that time. The erasing power was kept constant at each linear velocity irrespective of the difference between all recording waveforms.

As is clear from FIG. 4, in the case of the recording waveform WA, although the inclination is small, the higher the linear velocity, the larger the phase margin is preferable. Further, according to FIG. 5, there is also a fluctuation in the margin due to the temperature. This is governed by the temperature due to heating of the recording layers 3 and 7 in the case of overwriting,
This indicates that the temperature of the optical disk could not be set to the optimum state due to fluctuations in the linear velocity, the ambient temperature, manufacturing variations of the optical disk, and the like. As for the recording power, as shown in FIG. 6, in the recording waveform WA, the energy given to the recording layers 3 and 7 is given in a short pulse train, so that a large recording power is required. For this reason, especially at a high linear velocity, a semiconductor laser having a large output is required as a light source.

As in the case of the recording waveform WC of FIG. 7A, the laser power may be lower than the erase level before and after the recording pulse train of the recording waveform WA of FIG. 3B. In this manner, when recording is performed with a narrow mark interval, heat in an area irradiated with the recording power is diffused rearward, and the phenomenon of thermal interference in which a next recording mark is drawn largely can be reduced. This is effective for increasing the phase margin. If the period during which the laser power is lower than the erasing level is too long, the recording layers 3 and 7 do not reach the crystallization temperature or higher, and unerased portions occur. However, if the period τ lower than the erasing level is within the range of τ ≦ λ / V (λ: laser wavelength, V: relative speed between the laser spot and the optical disk), Pe and Pw before and after the period overlap. And Pe and Pw before and after the period.
The temperature is also increased by the conduction heat from the region irradiated by the above.
Therefore, the recording layers 3 and 7 reach the crystallization temperature, and the unerased residue can be reduced.

In the recording waveform WC, the laser power is lower than the erase level both before and after the recording pulse train.
There is a sufficient effect even if only one of the front and rear is used. If the level lower than the erasing level is set as the reproduction power level or the laser off level, the device configuration can be simplified. Similarly, in the recording waveform WB of FIG. 3, a level lower than the erasing level may be provided before and / or after the recording power. The recording waveform WA in FIG. 3 may be modulated between a recording power level and a reproduction power level or an off level of a laser in a period corresponding to a recording pulse train, like the recording waveform WD in FIG. 7B. In this method, since the recording layers 3 and 7 are rapidly cooled after melting at all locations in the recording mark, a stable recording mark can be formed, which is effective for increasing the phase margin.

Next, the optical disk device according to the present embodiment will be described with reference to FIGS. As shown in FIG. 11, in the DVD disk, since the sectors in the optical disk are spiral CLVs, the linear velocity is constant, and the inner area EA has 4 sector blocks and 1 block has 8 sectors (actually, 8 sectors). In a DVD, one block has 16 sectors, which is different from the actual case), and the outer peripheral area EB has 8 sector blocks, and one block has 8 sectors. The rotation cycle also
40 msec inside area EA, 80 outside area EB
msec.

Next, the main part will be described with reference to FIG. The start of reproduction or recording input by the key input unit 10 is determined by the system controller 12 and the signal processing unit 1
4 and the servo processor 16. The servo processor 16 controls the spindle motor 20 via a driver 18.
And the optical disk 22 rotates. The signal read from the optical pickup 24 is supplied to the preamplifier 26 shown in FIG. 10, where a reproduced signal and a servo signal are generated. The servo error signal is generated by a servo error signal generation circuit 49. The servo processor 16 processes the servo signals to generate focusing and tracking signals for tracks on the disk 22. Then, the actuator of the optical pickup 24 is driven by the driver 18 based on these signals, so that the servo control of the optical pickup 24 is performed in one cycle.

The reproduced signal is supplied to the preamplifier 26 shown in FIG.
And amplified by the RF amplifier 50. The frequency characteristics of the amplified reproduced signal are optimized by the equalizer 52,
PLL control is performed by the LL circuit 54. The comparison between the bit clock of the PLL and the time axis of the data and the jitter value generated by the jitter generation circuit 56 are performed by the system controller 12.
A / D-converts and measures, and the waveform correction circuit at the time of recording is changed according to this value. In the signal processing unit 14, the reproduced signal is converted into a digital signal, and for example, synchronization detection is performed. As a result, the NR from the EFM + signal on the optical disk
The data is decoded into Z data and subjected to error correction processing to obtain an address signal and a data signal of the sector. Since this signal is a signal compressed at a variable transfer rate, it is stored in the temporary storage memory 28 (4 MB DRAM),
Absorb the time axis of the variable transfer rate. The signal read from the temporary storage memory 28 is expanded by the AV decoder 30 and separated into audio and video signals.
Then, using a D / A converter (not shown),
It is converted and output to analog audio signals and video signals.

The speed signal of the optical disk 22 generated by the PLL circuit 54 of the preamplifier 26 is sent to the servo processor 16 so that the optical disk 22 is controlled by the speed signal.
The rotation is controlled by LV. The rotational position signal from the hall element of the spindle motor 20 is transmitted to the servo processor 16.
Then, the FG control of a constant rotation is also performed from the speed signal generated from this signal.

The overall control of each section described above is performed by the system controller 12. In addition, the microcomputer (not shown) recognizes the resolution of the image to be recorded or high-speed scenes such as car races, and recognizes key inputs and external control data for setting with priority on recording time. The recording time can be changed by the switching terminal, and the setting can be selected by an external user.

The optical pickup 24 uses a semiconductor laser as a light source, and forms a laser spot on the optical disk 22 using a collimating lens, an objective lens, and the like. The semiconductor laser is driven by the laser driving circuit 58 shown in FIG.
After the waveform is corrected by 0, it is input to the laser drive circuit 58. Here, the input signal is switched by the switching circuit 62 between the EFM + signal and the test pattern signal generated by the test pattern generation circuit 64. The waveform correction circuit 60 is a circuit that converts an EFM signal into a short pulse train (for a specific circuit configuration, see, for example, Japanese Patent Application Laid-Open No. 3-185628). When the laser drive circuit 58 is modulated with a short pulse train waveform, The recording waveform WA shown in FIG. 3B is obtained. Further, the waveform correction circuit 60 is a circuit for converting the pulse width to be short, and the laser driving circuit 58 has a shortened waveform.
Is modulated, a recording waveform WB shown in FIG. 3C is obtained.

The waveform correction circuit 60 can be constituted by a delay element and an AND circuit. That is, after the input signal is delayed by the delay element, the logical product of the input signal and the first input signal is obtained, whereby the recording waveform WB of FIG. 3C is obtained. In the waveform correction circuit 60, the switching of the time axis in a large unit is performed by the linear velocity switching circuit 62 based on the control of the system controller 12, and then the switching of the time axis shown in FIG. Detailed time setting of Ta, Tb, Tc, and Td is performed.

The test pattern generation circuit 64 similarly switches the time axis in large units by switching the linear velocity, and as a pattern, 3T which is the highest frequency of EFM +
For example, 3,4,3,5,3,6,3,7,
It is configured to generate a repetitive pattern of a signal of a fixed length such as 3, 8, 3, 9, 3, 10, 3, 11T. Here, a plurality of types of specific patterns may be recorded. Although not shown, a sensor such as a thermistor for detecting the temperature is provided in the vicinity of the optical disk 22, and a temperature detecting circuit 66 for detecting the temperature from the sensor is provided. The circuit configuration may be such that the temperature characteristics of the forward voltage of a semiconductor, for example, a diode inside the preamplifier 26 are measured.

When recording a signal, the present apparatus first irradiates a laser spot on the optical disk 22, and reads an address signal provided in advance on a signal track by an address reproducing circuit (not shown). Then, the linear velocity is set by the system controller 12. For example, in a mode in which (1) the image quality is good, but the overall recording time is about 2 hours, the linear velocity is 6 m / s. (2) The image quality is normal, but the overall recording time is about 4 hours. In the mode, the linear velocity is set to 3 m / s. (3) Although the image quality is poor, the linear velocity is set to 1.5 in the mode in which the entire recording time is about 8 hours.
m / s can be selected.

Further, as described above, in addition to the above, when the resolution of an image to be recorded or a high-speed scene such as a car race is selected, a key input for setting the recording time with priority and an external control data are used. Based on this, the recording time can be changed by the switching terminal, or the recording time can be changed by selection by an external user.

Although the CLV control is performed here,
Even when the inner and outer linear velocities are changed to about 30 zones by CAV control or zone CAV control, the linear velocity is set at each position while the system controller 12 manages the track address position. It is applicable by doing. In this case, a basic T cycle is set based on the set linear velocity.

Next, the operation of the present embodiment will be described with reference to FIGS. FIG. 12 shows a temporal change in the storage amount of the temporary storage memory 28. In the area a, a signal is written, and in the area b, the written signal is read. That is, a signal written at a read speed different from the write speed is read. FIG. 13 is a flowchart showing the procedure of the operation. First, an operation when recording original data such as audio and video will be described. First, a recording mode, a reproduction mode, or a standby mode is determined. In the case of the recording mode (step SA), data such as audio and video to be recorded is compressed, and an error correction code, an address, and a sync signal are added and recorded in the temporary storage memory 28 (a in FIG. 12). Area, step SB). This operation is performed until the temporarily stored data reaches the full level (first storage amount) (step SC). The value of the full level is a value obtained by taking a margin from the recovery time from the power save state, for example, 100 msec.
The time is about c. This value is set according to the compression ratio mode at the time of recording or a mode set from the outside.

When the amount of data stored in the temporary storage memory 28 reaches the full level, the data is
8 and written on the optical disk 22 (region b in FIG. 12, step SD). This operation is performed until the temporarily stored data reaches the empty level (second storage amount) (step SE). Then, when the empty level is reached, data reading is stopped (step SF). Then, data writing to the temporary storage memory 28 is performed again (step SB).

In the present embodiment, at the time when it is determined that the mode is the recording mode, the system controller 12 determines whether the optimization of the waveform correction of the recording signal has been completed (step SG). If the waveform correction optimizing process has already been performed, it is not necessary to perform this optimizing process many times. It is determined whether a predetermined time has elapsed after the setting of the optical disc 22 or the end of the optimizing process, or whether a predetermined temperature change has occurred. If either of them exceeds a predetermined value, the waveform correction process is performed. To do. If the optimization process has not been completed, a sector in which the original data is to be recorded is stored (step SH), and the mode shifts to the recording test mode (step SI).

In the recording test mode, as shown in step SI, while the original data is being recorded in the temporary storage memory 28, for example, an empty area is previously searched from the management area of the optical disk 22, and Recording layers 3 and 7
The pickup 24 moves to an area (recording track) where the test signal is radially closest to the current position by performing a focus jump to any one of the above, or the pickup 24 moves to an area dedicated to a predetermined recording test. I do. Then, a test pattern signal is written into the corresponding area of the disk 22 for one correction block, for example, 16 sectors (one sector is 2048 bytes). That is, the switching circuit 62 is switched to the test pattern generation circuit 64 side,
The test pattern signal is supplied to the laser drive circuit 58 via the waveform correction circuit 60. The laser drive circuit 58 records the input test signal on the optical disc 22. According to one method at the time of this recording, the light emission level of the laser is measured, a difference from the light emission level that should be originally calculated is calculated from the measured value, and the light emission level is corrected based on the difference.

In the second method, the test pattern signal is recorded while changing the laser power, and the pickup 24 kicks again on the recorded track, reproduces the test signal of this track and reproduces the test signal at each laser power. Measure jitter. Then, the waveform correction parameter at the laser power at which the jitter value becomes the best, that is, Ta to Td of the waveform correction circuit 60 is changed. The change of Ta to Td of the waveform correction circuit 60 which is a waveform correction parameter
The correction is performed using a correction coefficient that is compiled in a table in advance in accordance with the tendency of the characteristics of the optical disc 22. In this measurement, the jitter was measured, but the asymmetry may be measured instead of the jitter, and the laser power at which the asymmetry value becomes a predetermined value may be set as the optimum power.

The operation in the above-described recording test mode is performed within a time period from when the signal is accumulated in the temporary storage memory 28 until the signal reaches the full level. That is, the waveform correction circuit 60 is set with the value of the waveform correction parameter at the time when the level has reached the full level. At the end of the recording test mode,
The recording test mode of any of the corresponding recording layers 3 and 7 is released, and the pickup jumps to the recording sector of the original data stored at the time of the focus jump to any of the corresponding recording layers 3 and 7 to start. It waits (step SJ). Then, when the storage amount of the temporary storage memory 28 reaches the full level, the original data is recorded in the recording sector (steps SC and SD).

As described above, according to the present embodiment, the focus jump to one of the corresponding recording layers 3 and 7 is performed by utilizing the idle time of the pickup during the writing of the data to the temporary storage memory, and the test signal is Recording and reproduction are performed, and the jitter of the reproduction signal is measured.
Then, a correction parameter of the recording pulse waveform is set so as to reduce the jitter. For this reason, data recording can be performed without requiring any special time for setting the waveform correction parameters and without giving the user a sense of incongruity.

The present invention is not limited to the above-described embodiment, but includes, for example, the following.

(1) In the above embodiment, the waveform correction parameters are set when writing data to the temporary storage memory 28. However, the setting may be performed by using the idle time when reading data. FIG. 14 shows a change in the storage amount of the temporary storage memory 28 during reproduction. In the case of a DVD, the temporary storage memory 28 can store information for about 500 msec. Therefore, even if one round of the track is 80 msec, there is a time margin of about six rounds. Disc 2 by pickup 24
At the time when reproduction is started from the sector at the second predetermined position, tracking and focus error monitoring and error processing in signal processing are performed, and then signal writing to the temporary storage memory 28 is started (region c in FIG. 14). At the point in time when the level exceeds the empty level, the reproduction to the AV decoder 30 is started (the area d in the figure), and the reproduction signal from the pickup 24 is written to the temporary storage memory 28 until the level reaches the full level. When the level becomes full, the temporary storage memory 2
8 is prohibited (area e), and the A-V decoder 3
Reproduction to 0 is performed until the empty level is reached. At this time, usually, the track is kicked and waited so that the pickup 24 comes to the sector to be reproduced next. In this state, it is determined whether the waveform correction optimization processing has been completed. If the processing has not been completed, the above-described waveform correction optimizing process is performed.

(2) The change of the correction coefficient is not performed simply by the individual cycle T, but is performed by 3T, 11T, 3T,
It is more preferable to consider that the signal before and after the 3T signal such as 4T is short or long.

(3) In the above embodiment, it is conceivable that the recording and reproduction of the test signal are repeated many times. In order to reduce the number of repetitions, a temperature characteristic which greatly affects the recording characteristic shown in FIG. 5 is measured in advance by the temperature sensor. Then, the correction coefficients Ta to Td are corrected based on the measured values. For example, if the measured temperature is 10 degrees, the optical disk 22 is hard to warm up, so the direction is changed to increase Td with respect to Tc. When the temperature is as high as 40 degrees, the temperature is changed in such a manner that Tc is made longer than Td.

(4) In the above embodiment, the jitter value of the reproduction signal of the test signal is measured, because the jitter value is related to the quality of the reproduction signal. For example, RF signal,
In particular, a high frequency component such as the 3T signal may be extracted and the amplitude may be controlled so as to be maximum.

(5) It is known that the phase change optical disc as described above has a limit on the number of times of recording, and that the jitter increases as the number of times of recording increases. Therefore, in a preferred embodiment, there is provided means for counting the number of times of recording by linking to a track, and this number of times of recording is updated. Then, with the increase in the number of times of recording, for example, the limit jitter value at the end of test recording is increased. Further, it is desirable that the time from Ta to Td be changed stepwise, as the number of recordings changes so as to prevent good recording.

(6) In the above embodiment, when the linear velocity which is the highest transfer rate is 6 m / s as the waveform correcting means, the signal waveform shown in FIG. 3C is used to simplify the recording signal generation circuit. ing. However, even at a linear velocity of 6 m / s, a plurality of different types of correction means may be used.

(7) In the above embodiment, as a waveform correcting means, a signal is recorded after correcting the waveform of a recording pulse into a pulse train composed of a plurality of short pulses in a region where the linear velocity is low, and the recording pulse is recorded in a region where the linear velocity is high. After a short waveform correction, record the signal. However, the optimal waveform correction may vary depending on the structure and type of the optical disc, and the waveform shown in the above embodiment is not always the optimal correction. For example, in some cases, a method of correcting the waveform of a recording pulse into a pulse train composed of a plurality of short pulses regardless of the linear velocity is employed, and the amplitude of the short pulse train converted in a region where the linear velocity is high and a region where the linear pulse is low are changed. For example, it is possible to increase the phase margin in the entire area of the optical disk by a method such as increasing the amplitude of the tip portion in a region where the linear velocity is high, and such a correction method is also included in the present invention.

(8) Irrespective of the linear velocity, a method of correcting the waveform of the recording pulse into a pulse train composed of a plurality of short pulses is adopted, and the pulse width of the short pulse train converted in the region where the linear velocity is high and the region where the linear velocity is low is adjusted. You may change it. For example, in a region where the linear velocity is low, the recording waveform is the recording waveform WE in FIG.
In the region where the linear velocity is high, the pulse width of the short pulse train of the recording waveform WE is widened to obtain the recording waveform WF shown in FIG.
Since the heat storage effect at the time of signal recording decreases as the linear velocity increases, even if the pulse length of the short pulse train is increased, the tear-like distortion does not increase. When the pulse width of the short pulse train is increased, the energy supplied to the recording layer increases, and as a result, the recording power can be reduced as compared with the case where the pulse width is narrow.

In the recording waveforms WE and WF shown in FIG. 8, as in the recording waveforms WC and WD in FIG. 7, the laser power is made lower or lower than the erase level before and / or after the recording pulse train. May be modulated between the recording power and the reproduction power level or the off level of the laser during the period corresponding to

(9) In the above-described embodiment, the present DVD standard is a two-layer disc which is exclusively used for reproduction. For example, one of the two layers is constituted by a phase-change recording layer, and the other is reproduced. The present invention can be applied to any one of a two-layer optical disc that is a dedicated layer and a two-layer optical disc that is a phase-change recording layer, as shown in FIG. In addition, the present invention is similarly applicable to a multilayer optical disc in which at least one layer is a phase change recording layer. On the other hand, the configuration of the apparatus of the present invention is as follows. On the recording layer of a multilayer optical disc having at least one recording layer that changes phase reversibly optically, optical data is recorded with pulse width modulated recording data of input data to be recorded. An optical pickup means for irradiating a recording laser beam obtained by modulation to form a mark and irradiating a reproduction laser beam on the mark to reproduce the recording data, and for reaching the first storage amount of the input data A temporary storage unit that reads the input data written at a read speed different from the write speed until the input data written reaches a second storage amount lower than the first storage amount, and supplies the read input data to the optical pickup unit; Focus jump control is performed on the optical pickup means so as to focus and irradiate a recording laser beam or a reproduction laser beam onto each layer of the multilayer optical disc. An optical pickup control unit, and during the period in which the input data is written to the temporary storage unit, and during an idle time when the optical pickup unit does not perform each of the recording, reproduction, and seek operations, or the temporary storage. Performing a recording test on the recording layer during a period during which the input data is being read from the unit and within an idle time when the optical pickup unit does not perform each of the recording, reproducing, and seeking operations. Waveform correction means for storing a waveform correction value for correcting the pulse waveform of the recording data on the device side and / or the multi-layer optical disc side based on the result, and at the time of recording, using the waveform correction value to record the recording data. An optical disc recording / reproducing apparatus characterized by performing waveform correction. Further, means for recognizing a multilayer optical disc having two or more layers, means for recognizing that at least one layer is a phase change recording layer,
Focus jump means for focusing and irradiating the light spot, and waveform correction means for testing and storing waveform correction values of a plurality of phase change recording layers are provided.

(10) The present invention can be similarly applied to an optical disk device having no compression / decompression block, for example, a computer peripheral device such as a DVD-RAM or a DVD-R / W. These devices record and reproduce compressed / decompressed data, but do not have a compression / decompression circuit as a device. For example, compressed data is output to an external computer via a bus such as ATAPI or IEEE 1394 without being expanded, and is expanded by software on the computer. In such devices controlled by an external control input, in order to optimize recording, a pickup records, reproduces,
Or, it monitors the busy state or the unselect state such as during the seek operation, and performs the waveform correction optimizing process when the state becomes the unselect state.

For this purpose, first, with the optical disk activated, it is determined whether the type of the optical disk, that is, whether it has a single layer or a multi-layer or a recording layer, by either inserting the optical disk or turning on the power. And there is a recording layer, and
Determine if recording optimization is required. The necessity of recording optimization is indicated by, for example, a flag. For example, when the power is turned on or the optical disk is inserted, the logical value is "0", which indicates that recording optimization is required. Then, once the optimization is completed, the flag becomes “1”. However, when a predetermined time has elapsed, or when the temperature of the apparatus at the time of obtaining the waveform correction value is measured, and there is a predetermined temperature change with respect to the temperature measured at the time of the previous optimization, , The flag becomes “0”. By checking this flag, if there is a recording layer, the unselect state is monitored, and the waveform is optimized at that time. As a configuration, a focus jump unit for focusing on the signal surface of each layer may be provided, and the waveform correction unit may test the waveform correction values of a plurality of recording layers and store an optimal waveform correction value. Based on the determination whether the type of the multilayer optical disc is read-only or recordable,
In the case of a recordable multilayer optical disc, a focus jump to a predetermined recording layer is performed during a recording test, and the track returns to the original recording layer when the test recording is completed.

(11) With a removable optical disk, it is necessary to stably reproduce what has been recorded by one device by another device. However, with the improvement in recording density, such stable reproduction is becoming difficult. In the above-described embodiment, the optimum recording is performed in the own apparatus, but a method for improving the compatibility in another apparatus will be described below. In such a case, by recording the waveform correction value on the optical disc, when the optical disc is started, if the correction value is referred to, there is no need to perform test recording again. Recording can be easily performed.
That is, the waveform correction value may be recorded on either the apparatus side or the optical disk side (in other words, the waveform correction value is stored on the apparatus side and / or the multilayer optical disk side). In addition, the waveform correction value is (at the same time as) simultaneously with the unique identification mark (disc unique identification information) of the optical disc.
Record it also on the device side. Accordingly, when the waveform correction value is recorded in the apparatus, when the same optical disc is started again by the same apparatus, test recording is performed again by referring to the identity of the unique identification mark of the optical disc and the waveform correction value. When recording the waveform correction value on the optical disk at the time of shipment of the optical disk, the apparatus reads out the waveform correction value, refers to the waveform correction value, and records the correction value on the optical disk, so that the optimum value is recorded. Recording can be done easily.

As a specific example, in the case of a DVD, the lead-in area has a radius of less than 24 mm at the innermost circumference of the optical disk. The area after 24 mm is a data area. Conventionally, in the lead-in area, the type of optical disk (playback only, write once, recording / playback type), layer (single layer disk, double layer optical disk, parallel, opposite), reflectance (single layer 0.7, 2)
Layer 0.3), physical information such as a start address and an end address of the data are described.

In this embodiment, in addition to these, the optimum recording laser power (power is shown in FIG.
3B shows an amplitude value corresponding to a laser power such as Pw or Pe of a recording waveform as shown in FIG. 3B, and an optimum recording waveform correction value (the correction value is basically a temporal profile of FIG. 3B). This shows the temporal relationship between certain Ta and Td.
These four values may be recorded, or a symbol such as a table of a plurality of types of these values may be recorded), the linear velocity, and the recording temperature (may be omitted as the above conditions). , A recording device (specifying the recording device when recorded in the market), a maker name (only the manufacturer of the optical disc when recorded at the time of manufacture. The device maker is recorded in accordance with the data), the manufacturing lot No.
only. If the information is also recorded in the market, the optical disk maker and the device number corresponding to the above data are recorded).

(12) When recording is performed on a two-layer optical disk by the optical disk device, the recorded data may be encrypted so as not to be read by another company. They may be collectively recorded on the recording layer.

The recording / reproducing apparatus for such an optical disk may be exactly the same as that of the above-described embodiment. However, test recording is performed in a test recording area prepared in a lead-in area as a test recording area. . In addition to this area, any area may be used as long as the recorded data is not destroyed by normal data recording / reproduction. At the time of the first start-up, the recording / reproducing apparatus reproduces the test recording area and the like in the lead-in area and also reproduces the waveform correction value. If there is no waveform correction value, the above-described recording test is performed to measure the optimum value of the waveform correction parameter, and the measured optimum value is encoded and written in the recording area. Thus, if the recording correction is performed by reproducing the optimum value from the next time, it is not necessary to perform the correction work again. At this time, the name of the manufacturer, the manufacturing lot number, and the like are confirmed, and, for example, a method of reading the correction value changes depending on the manufacturing lot.

The same applies to the case where correction values have been recorded on the optical disc in advance. At the time of the first start-up, the test recording area prepared in the lead-in area is reproduced, and the waveform correction value is reproduced. Then, the correction value is reproduced by a decoder, and the waveform correction value is stored in a register for recording by referring to the name of the optical disk maker, the production lot number, and the like. At the time of subsequent recording, data is written using this waveform correction optimum value.

(13) More specifically, the temperature at the time of measurement is measured by the temperature sensor, and the value of this temperature is recorded together with the correction value. Conditions such as linear velocity are also recorded at the same time. Then, when reproducing these conditions at the same time at the time of reproduction and performing new recording, parameters such as temperature and linear velocity at that time are compared, and as a result, if there is a difference between them, this difference and this are corrected. Correct the correction value from the calculation formula or table to be used. Then, the corrected value is recorded as an optimum value.

(14) In the case of a two-layer optical disk, if the recording area is on the first layer and the data of the second layer is also written intensively on the first layer, the processing at the time of reproduction is simplified. In this case, data of two layers is reproduced as in the case of a single layer,
The setting is performed for each layer, but when there is no data and the correction value is recorded, first, the above-described recording test is performed on the first layer to measure the optimum value. Then, the recording test is performed by performing a focus jump to the second layer, and an optimum value is measured. After that, these two data are encoded, moved to the recording area of the first layer, and the optimum value is written in this recording area. Thus, from the next time onward, if this optimum value is reproduced and recording correction is performed, it is not necessary to perform correction work again.

The present invention having the above-described configuration may further include the following configuration. That is, the disc-specific identification information read from the multilayer optical disc may be recorded together with the waveform correction value. Further, the disc unique identification information and the waveform correction value may be reproduced. The test signal used in the recording test is composed of a predetermined number of repetitive signals of a specific signal sequence that shows a tendency for jitter to deteriorate when the test signal is recorded and reproduced. The repetition of the specific signal sequence of the test signal may include at least the shortest wavelength among the recording wavelengths. Further, the means for evaluating the quality of the waveform correction value includes a measuring means for measuring a jitter value of a signal reproduced from the waveform correction value, and a determination for judging whether the jitter value measured by the measuring means is within a predetermined value. Means for storing the test signal so as to use the recording parameter when recording the test signal when the result of the determination by the determining means is within the predetermined value; and If the result of the determination in step (1) is out of the predetermined value, the quality of the test signal may be re-evaluated by changing a recording parameter, and the quality of the test signal may be re-evaluated. A coefficient means for counting the number of quality re-evaluations performed by the quality re-evaluation means; and a prohibition means for prohibiting the writing of the test signal when the count value of the coefficient means exceeds a prescribed value. May be further provided. Further, according to a temperature measuring means for measuring a reference temperature on the device side when the optimal waveform correction value is obtained, and according to a temperature change from the reference temperature measured by the temperature measuring means,
The apparatus may further include a temperature changing unit for changing the waveform correction value. Further, the apparatus may further include a recording number management unit that manages the number of recordings of the overwritten recording data, and a number changing unit that changes the waveform correction value according to the number of recordings counted by the recording number management unit. . Further, the present invention is a multi-layer optical disc having at least one recording layer which can be recorded and reproduced by the above-described optical disc recording / reproducing apparatus and has an optically reversible phase change. The optical disk may further include a test recording area for recording a waveform correction value for correcting a pulse waveform of the recording data based on the recording data. Further, the test recording area may be provided in a lead-in area, and may record the waveform correction values of all the recording layers.

[0065]

As described above, according to the present invention,
The recording signal waveform of the data is corrected by using the idle time of the pickup generated at the time of writing or reading data in the temporary storage means for temporarily storing data at the time of recording or reproduction. Data recording can be performed satisfactorily without requiring time for waveform correction.

[Brief description of the drawings]

FIG. 1 is a recording waveform diagram showing a basic operation of the present invention.

FIG. 2 is a main cross-sectional view illustrating an example of an optical disc.

FIG. 3 is a diagram showing a recording waveform according to one embodiment of the present invention.

FIG. 4 is a diagram illustrating a relationship between a linear velocity and a phase margin in various recording waveforms.

FIG. 5 is a diagram illustrating a temperature variation of a relationship between a linear velocity and a phase margin.

FIG. 6 is a diagram illustrating a relationship between a linear velocity and a recording power in various recording waveforms.

FIG. 7 is a diagram showing another recording waveform according to the present invention.

FIG. 8 is a diagram showing another recording waveform according to the present invention.

FIG. 9 is a block diagram showing a main part of the optical disc device according to the present embodiment.

FIG. 10 is a block diagram illustrating a configuration example of a preamplifier in FIG. 9;

FIG. 11 is a diagram showing a form of an optical disc in a DVD.

FIG. 12 is a diagram showing a change in a storage amount at the time of writing data in a temporary storage memory.

FIG. 13 illustrates a main operation in one embodiment.

FIG. 14 is a diagram showing a change in a storage amount when data is read from a temporary storage memory.

FIG. 15 is a diagram showing a state of a recording mark being made into teardrops.

FIG. 16 is a diagram showing a state of correction of a recording mark according to a conventional technique.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Key input part 12 ... System controller 14 ... Signal processing part 16 ... Servo processor 18 ... Driver 20 ... Spindle motor 22 ... Optical disk, multilayer optical disk 24 ... Pickup 26 ... Preamplifier 28 ... Temporary storage memory 30 ... Decoder 49 ... Servo error signal Generation circuit 50 Amplifier 52 Equalizer 54 PLL circuit 56 Jitter generation circuit 58 Laser drive circuit 60 Waveform correction circuit 62 Switching circuit 64 Test pattern generation circuit 66 Temperature detection circuit

Claims (15)

[Claims] 1. A multi-layer optical disc having at least one optically reversible phase-change recording layer on the recording layer.
An optical pickup for irradiating recording laser light obtained by optically modulating input data to be recorded with pulse width modulated recording data to form a mark, and irradiating a reproduction laser beam on the mark to reproduce the recording data Means for writing the input data until a first storage amount is reached;
A temporary storage unit that reads the written input data at a read speed different from the write speed until the input data reaches a second storage amount lower than the first storage amount, and supplies the read data to the optical pickup unit; Optical pickup control means for performing focus jump control on the optical pickup means so as to focus and irradiate a recording laser light or a reproduction laser light on each of the layers, and the input data is written to the temporary storage means. During a period during which the optical pickup means is not performing recording, reproduction, and seek operations, a recording test is performed on the recording layer, and a pulse waveform of the recording data is generated based on the test result. And / or a waveform correction means for storing a waveform correction value for correcting the error on the device side and / or the multilayer optical disc side, , An optical disc recording and reproducing apparatus which is characterized in that the waveform correction of the record data by using the waveform correction value. 2. A multi-layer optical disc having at least one optically reversible phase-change recording layer on the recording layer,
An optical pickup for irradiating recording laser light obtained by optically modulating input data to be recorded with pulse width modulated recording data to form a mark, and irradiating a reproduction laser beam on the mark to reproduce the recording data Means for writing the input data until a first storage amount is reached;
A temporary storage unit that reads the written input data at a read speed different from the write speed until the input data reaches a second storage amount lower than the first storage amount, and supplies the read data to the optical pickup unit; Optical pickup control means for performing focus jump control on the optical pickup means so as to focus and irradiate a recording laser light or a reproduction laser light onto each of the layers, and the input data is read from the temporary storage means. And the optical pickup means is recording, reproducing,
A recording test is performed on the recording layer during an idle time during which no seek operation is performed, and a waveform correction value for correcting a pulse waveform of the recording data is set on the apparatus side and / or the multi-layer based on the test result. An optical disc recording / reproducing apparatus, comprising: a waveform correcting means for storing the data on an optical disc side, wherein at the time of recording, the waveform of the recording data is corrected using the waveform correction value. 3. The optical disc recording / reproducing apparatus according to claim 1, wherein disc-specific identification information read from the multilayer optical disc is recorded together with the waveform correction value. 4. The optical disc recording / reproducing apparatus according to claim 3, wherein the disc-specific identification information and the waveform correction value are reproduced. 5. A test signal used in the recording test, comprising a predetermined number of repetitive signals of a specific signal sequence showing a tendency for jitter to deteriorate when the test signal is recorded / reproduced. The optical disk recording / reproducing apparatus according to claim 1. 6. The optical disk recording / reproducing apparatus according to claim 5, wherein the repetition of the specific signal sequence of the test signal includes at least the shortest wavelength among the recording wavelengths. 7. A means for evaluating the quality of the waveform correction value, a measuring means for measuring a jitter value of a signal obtained by reproducing the waveform correction value, and determining whether or not the jitter value measured by the measuring means is within a predetermined value. Determining means for determining, if the determination result determined by the determining means is within the predetermined value, a recording parameter setting means for storing the test signal so as to use the recording parameter when recording the test signal, 2. A quality re-evaluation means for changing a recording parameter and re-evaluating the quality of the test signal when the result of the determination by the determination means is out of the predetermined value. An optical disk recording / reproducing apparatus according to claim 7. 8. A coefficient means for counting the number of quality re-evaluations performed by the quality re-evaluation means, and when the count value of the coefficient means exceeds a prescribed value, writing of the test signal is prohibited. 8. The optical disk recording / reproducing apparatus according to claim 7, further comprising a prohibition unit for performing the operation. 9. A temperature measuring means for measuring a reference temperature on the device side when the optimum waveform correction value is obtained, and said waveform correction is performed according to a temperature change from said reference temperature measured by said temperature measuring means. 9. The optical disk recording / reproducing apparatus according to claim 1, further comprising a temperature changing unit for changing a value. 10. A recording number management means for managing the number of recording times when the recording data is overwritten, and a number changing means for changing the waveform correction value according to the number of recording times counted by the recording number management means. The optical disk recording / reproducing apparatus according to any one of claims 1 to 9, wherein: 11. The optical disk recording / reproducing apparatus according to claim 1, wherein the recording layer on which the recording test is performed is a layer different from a layer on which recording or reproducing is currently performed. apparatus. 12. The recording area of the recording layer on which the recording test is performed is a free area closest to an area on which recording or reproduction is currently performed.
An optical disc recording / reproducing device according to any one of the above. 13. The recording area of the recording layer on which the recording test is performed is a free area closest to the area on which recording or reproduction is currently performed and different from the layer on which recording or reproduction is currently performed. The optical disk recording / reproducing apparatus according to any one of claims 1 to 10, wherein: 14. An optical disk recording / reproducing apparatus according to any one of claims 1 to 13, capable of recording and reproducing.
What is claimed is: 1. A multi-layer optical disc having at least one optically reversible phase-change recording layer, wherein a waveform correction value for correcting a pulse waveform of the recording data based on a result of a recording test performed on the recording layer. An optical disc, comprising a test recording area for recording information. 15. The optical disk according to claim 14, wherein the test recording area is provided in a lead-in area, and records the waveform correction values of all the recording layers.