JP2003263741A - Optical information recording apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical information recording apparatus which accurately controls light-emitting power in a method for recording information on a recording medium by irradiating the medium with a laser beam by carrying out the multi-pulse emission from a laser beam source under a predetermined light-emission rule with at least two or more power levels of a bias level and a peak level. <P>SOLUTION: When carrying out trial writing for determining the light- emission power for recording prior to actually recording the information, the differential efficiency of the laser beam source is also calculated in the same focus-on state as in an original recording operation. The differential efficiency is calculated in the same conditions as in the actual recording operation, and the light-emission power in recording is accurately determined and controlled by the trial writing. In the multi-pulse emission, light is emitted with a single pulse waveform when treating long mark data of 10 T or more so as to detect the peak level, and the detected peak level is provided for the calculation of the differential efficiency. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical information recording device for recording information on a recording medium such as an optical disc by a laser beam from a laser light source.

[0002]

2. Description of the Related Art With the spread of multimedia, music CDs
(Compact Disc), CD-ROM, recently DVD
A reproduction-only medium (recording medium) such as a (Digital Versatile Disc) -ROM and an information reproducing apparatus have been put into practical use. Recently, in addition to write-once optical discs using dye media and rewritable MO discs using magneto-optical (MO) media, phase-change media have also attracted attention, and information using these recording media has been attracting attention. A recording / reproducing device has been put into practical use. Also, rewritable DVD media have attracted much attention as next-generation multimedia recording media and large-capacity storage media. The phase-change type medium is for recording information by reversibly changing the recording material into a crystalline phase and an amorphous phase. In addition, unlike the MO media, the phase-change type media does not require an external magnetic field and can record and reproduce information only by laser light from a light source composed of a semiconductor laser, and information can be recorded and erased once by laser light. It is possible to perform overwrite recording that is performed at the same time.

As a general recording waveform for recording information on a dye type medium, for example, there is a single pulse semiconductor laser emission waveform generated based on an 8-16 modulation code (EFM modulation code). In the single pulse recording with this recording waveform, there is a problem that the recording mark is distorted like a tear due to heat storage. Therefore, as an LD emission waveform rule (strategy) for recording information on a dye-based medium, as shown in FIG. 5C, a dye is generated by laser light having a multi-pulse waveform based on recording data such as an EFM modulation code. A method of forming a mark on a system medium has been proposed.

A method has been proposed in which the mark portion of this multi-pulse waveform is composed of a head heating pulse A and a plurality of subsequent continuous heating pulses B. C indicates an unheated light emitting portion of the multi-pulse portion, and D indicates a space portion. Further, the light emission power Pw of the heating pulses A and B shows a peak power, and the light emission power Pb of the portions C and D (≈Pr)
Indicates bottom power.

Further, in order to record information on the phase change medium, as shown in FIG.
It is common to form marks by laser light having a multi-pulse waveform using Pe and Pb (three values). The mark portion of this multi-pulse waveform has a head heating pulse A for preheating the recording film of the phase change medium sufficiently above the melting point, a plurality of subsequent continuous heating pulses B, and continuous cooling therebetween. It consists of pulse C. Heating pulse A,
B emission power (peak power) is Pw, cooling pulse C
Letting Pb be the light emission power (bottom power) and Pr be the read power, each light emission power is set to Pw> Pb.apprxeq.Pr. The space portion of the multi-pulse waveform is composed of the erase pulse D, and the emission power (erasing power) Pe thereof is set to Pw>Pe> Pb.

When recording on a dye-based medium or a phase change medium, it is necessary to correctly control the recording light emission power. Since a driving current-emission power characteristic of a semiconductor laser easily fluctuates due to self-heating, etc., APC (Aut
omatic Power Control) control is performed. This is because a part of the emitted light of the semiconductor laser is a photo detector (PD).
The drive current for the semiconductor laser is controlled by using a monitor current generated in proportion to the emission power of the semiconductor laser.

When only information reproduction is taken into consideration, a high frequency current is generally superimposed on the drive current of the semiconductor laser for noise suppression, but since it is a constant current in terms of direct current, feedback in a relatively low band is performed. APC can be easily realized by forming a loop.

However, when performing APC during recording,
Since the recording power changes at high speed to form the marks / spaces, it is necessary to devise control. For example, CD
System and DVD system, recorded data DSV (Digital Sum
If a feedback loop of a low band is configured by utilizing the fact that the value of (Value) becomes zero, the recording power can be controlled with the same simple structure as that at the time of reproduction, but the accurate power cannot be controlled. .

Therefore, for example, when recording is performed on a CD-R (dye-based) medium by the strategy shown in FIG. 7C, for example, the maximum data length is 11
If the light emission power is sampled / held for each mark / space when recording the data of the mark or space of T length, the control band may be several MHz even when the disc rotation speed is set to about 4 times speed. The recording power can be accurately controlled with a relatively inexpensive structure.

However, in the case of a DVD type medium, it is desirable that both the dye type / phase change type are recorded by using the above-mentioned multi-pulse emission waveform instead of single pulse emission, and the peak level power detection is performed. However, a simple sample / hold circuit requires a very high-speed control band in the light receiving system and the subsequent circuit, which is not practical.

As a method of solving such a problem,
According to Japanese Unexamined Patent Publication No. 9-171631, by providing a period in which an emission waveform of a semiconductor laser is appropriately driven in a non-pulse state, an amorphization level (peak power) and a reading level (bottom power) during recording on a phase change medium are provided. Power).

When the technique disclosed in Japanese Unexamined Patent Publication No. 9-171631 is applied to the mark recording power control of the recording strategy of the dye-based medium as shown in FIG. 5C, the portion recorded in the non-pulse state The recording mark is not formed well due to continuous heating and becomes a defective portion. However, since the APC operation is performed at a relatively long interval, the error correction function hardly affects the reproduction. Further, since the space recording power is generally a constant power, it is possible to control the space recording power without damaging the recording data by sampling / holding when recording relatively long space data. Therefore, the space recording power control interval can be controlled at a shorter interval than the mark recording power control interval.

On the other hand, since the optimum value of the recording power changes depending on the ambient temperature, the type of recording medium, the linear velocity, etc., generally in a dye medium or a phase change medium, an OPC (Optimum Power Control) is performed before recording information. The recording power is optimized by so-called trial writing. OPC
Is a recording media PCA (Power Calibration Are
This is performed by trial-writing, recording and reproducing predetermined information in a predetermined area called a). Specifically, test data of a predetermined pattern consisting of marks (3T) to 14 times (14T) three times the channel clock period T is recorded by changing the emission power in multiple steps, and this test data is reproduced. Then, DC modulation of the RF signal at each power, asymmetry of the RF signal after AC coupling, and the like are calculated as evaluation criteria. Modulation M is
For example, assuming that the maximum amplitude of the RF signal is Ip-p and the maximum value of the RF signal is Imax, M = Ip-p / Imax ............ (1) In addition, asymmetry β after AC coupling
Is the positive peak level X1 of the RF signal after AC coupling,
It is expressed as follows using the negative peak level X2.

Β = (X1 + X2) / (X1−X2) (2) where X1 + X2: difference between positive and negative peak levels of RF signal after AC coupling X1−X2: RF signal peak to peak after AC coupling It is a value. The optimum recording power is obtained based on the modulation M and the asymmetry β after AC coupling.

[0015]

The LD drive current-LD emission power characteristics of this type of semiconductor laser are shown in FIG.
Shown in. When driving the semiconductor laser to emit light, a driving current is supplied.
With respect to the bias current Ib for light emission of the reference bias power Pb, the erase level superimposed current ΔIe and the peak level superimposed current (ΔIe + Δ) when the erase power Pe (in the case of a phase change type medium) and the peak power Pw are emitted.
Ip) is superposed. Erase level superimposed current ΔIe and peak level superimposed current (ΔIe + ΔI
p) can be obtained from the differential efficiency η of the semiconductor laser and the erase level.

That is, the differential efficiency η is defined as the slope ΔP / ΔI of the LD drive current-LD emission power characteristic of the semiconductor laser as shown in FIG. Assuming that the driving currents of the semiconductor laser corresponding to the bottom power Pb / erase power Pe / peak power Pp are Ib, Ie, and Ip, respectively, the bottom power Pb / peak power Pp has the following relationship.

Pb = Pe−η (Ie−Ib) = Pe−η · ΔIe Pp = Pe + η (Ip−Ie) = Pe + η · ΔIp From the above equations, the erase level superimposed current ΔIe and the peak level superimposed current ΔIe + ΔIp are as follows. Can be asked for.

[0018] ΔIe = (Pe−Pb) / η ΔIe + ΔIp = (Pb−Pe) / η

Therefore, in order to perform the recording operation, it is necessary to previously calculate the differential efficiency η of the semiconductor laser and determine the drive current for each power level. In general, the recording operation is performed in the focus-off state prior to the recording operation, and the recording level power is sampled to calculate the differential efficiency η.

However, as described in Japanese Patent No. 2553284, the differential efficiency characteristic of the semiconductor laser changes depending on the focus on / off due to the influence of so-called return light, which is reflected light from the medium returning to the semiconductor laser. There's a problem. Even if the differential efficiency is obtained in the focus-off state before the recording operation, there is an error in the differential efficiency in the recording state (that is, the focus-on state), so that the emission power cannot be controlled accurately.

An object of the present invention is to provide an optical information recording device capable of accurately controlling the light emission power in recording operation.

Particularly, in a system for recording information by causing a laser light source to irradiate a laser beam on a recording medium by multi-pulse light emission according to a predetermined light emission rule based on at least a binary or more power level of a bias level and a peak level. An object of the present invention is to provide an optical information recording device capable of accurately controlling the light emission power.

[0023]

The invention according to claim 1 is
According to the information having the data length based on the predetermined recording modulation method, the laser light source is caused to emit the pulsed light in accordance with the predetermined light emission rule with the power level of at least the binary value of the bias level and the peak level to emit the laser light on the recording medium. In an optical information recording device for irradiating and recording information, test writing is performed by changing the emission power of the laser light source in multiple steps to a predetermined area on the recording medium before recording information. Means, and a monitor element for outputting a current corresponding to the light emission power of the laser light source as a monitor signal,
Focusing the laser light source by a differential efficiency calculation means for calculating the differential efficiency of the laser light source based on the emission power of the laser light source and a monitor signal obtained from the monitor element, and a differential efficiency calculation processing by the differential efficiency calculation means. Differential efficiency calculation processing control means that is caused to emit light in the ON state and that is executed when trial writing is performed by the test writing means, and power that determines the light emission power during recording using the differential efficiency calculated by the differential efficiency calculation means And a determining unit.

Therefore, when the test writing for determining the light emission power at the time of recording is performed prior to the recording of the information, the differential efficiency of the laser light source is also calculated in the focus-on state so that the original recording operation does not occur. Without affecting, the differential efficiency is calculated under the same conditions as during the recording operation, and the light emission power during recording can be accurately determined and controlled.

According to a second aspect of the present invention, in the optical information recording apparatus according to the first aspect, the differential efficiency calculation processing control means sets the emission power of the laser light source in multiple stages during trial writing by the trial writing means. Immediately before changing and performing trial writing recording, a recording operation is performed with a constant light emission power for a predetermined period, and the differential efficiency calculation unit calculates the differential efficiency.

Therefore, in the system for recording information by causing the laser light source to irradiate the laser light on the recording medium by multi-pulse light emission according to a predetermined light emission rule with at least a binary or more power level of the bias level and the peak level. Also, the differential efficiency can be calculated accurately.

According to a third aspect of the present invention, in the optical information recording apparatus according to the second aspect, one trial writing is performed in a block unit composed of a plurality of sectors, and the differential efficiency calculation processing control means is concerned. A recording operation is performed with a constant light emission power for a predetermined number of sectors in a block, the differential efficiency is calculated by the differential efficiency calculating means, and the test writing means emits light from the laser light source for the remaining sectors in the block. The power was changed in multiple steps so that trial writing could be performed.

Therefore, it is possible to appropriately execute the differential efficiency calculation process and the trial writing process within the original range of the trial writing process without preparing a special area for calculating the differential efficiency.

According to a fourth aspect of the present invention, in the optical information recording apparatus according to the third aspect, the trial writing means has multi-step light emission determined based on the differential efficiency calculated immediately before trial writing in the block. Test writing is performed for each sector by power.

Therefore, in the trial writing stage, trial writing can be performed with more appropriate light emission power using accurate differential efficiency, and the light emission power for recording to be determined becomes more appropriate.

The present invention as defined in claim 5 is any one of claims 1 to 4.
In the optical information recording device according to any one of the above, the predetermined recording modulation method is to cause multi-pulse light emission at the time of recording mark information, and the differential efficiency calculation processing control means, when calculating the differential efficiency immediately before trial writing. In the detection of the laser power of the laser light source in (1), the peak level light emission power is detected by emitting light in a single pulse state for a predetermined period.

Therefore, in the system for recording information by causing the laser light source to emit multi-pulses in accordance with a predetermined light emission rule with a power level of at least two values of the bias level and the peak level and irradiating the laser light on the recording medium. Also, the differential efficiency can be calculated accurately.

According to a sixth aspect of the present invention, in the optical information recording apparatus according to the fifth aspect, the differential efficiency calculation processing control means, when the data length is a predetermined length or more, the peak level is a single pulse state for a predetermined period. To emit light.

Therefore, the invention according to claim 5 can be easily realized by using so-called long mark data.

[0035]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described with reference to FIGS. In this embodiment, the DVD
An example of application to an optical information recording / reproducing apparatus as an optical information recording apparatus for recording (adding) code data in a ROM format on a dye-based medium is shown, and a recording modulation method is 8-
Mark edge (PWM: Pulse Width Modulation) recording is performed using 16 modulation codes (EFM modulation codes). In the present embodiment, by using such a medium and recording data, a semiconductor laser as a laser light source is caused to emit a multi-pulse with an emission waveform as shown in FIG. 5 for recording to form a recording mark / space. Information is recorded.

FIG. 1 shows an example of the basic overall structure of such an optical information recording / reproducing apparatus capable of recording / reproducing, and FIG. 2 shows an example of the internal structure of the system controller.

In the optical information recording / reproducing apparatus 1 of the present embodiment, a laser beam is applied to a recording medium 2 of, for example, DVD + R which is rotationally driven by a spindle motor (not shown) for reproducing or recording operation. A semiconductor laser (LD) 3 is provided as a laser light source that emits light. The laser light emitted from the semiconductor laser 3 is converted into a parallel light flux by the collimator lens 4, and then passes through the polarization beam splitter 5 and the objective lens 6 to make a recording medium 2.
It is focused and illuminated on top. The return light reflected from the recording medium 2 passes again through the objective lens 6 and again the polarization beam splitter 5
Is reflected by the incident light to be separated from the incident light and is incident on the divided light receiving element (PD) 8 whose light receiving region is divided into four by the detection lens 7 and is received. The light receiving signal of each divided area received by the divided light receiving element 8 serves as the basis of the RF signal serving as an information signal, the focusing servo signal Fo, and the tracking servo signal Tr. / Amplified R
The F signal is input to the system controller 10 and is used to output reproduction data as a reproduction signal.

On the other hand, focusing servo signal Fo
The tracking servo signal Tr and the tracking servo signal Tr are input to a Fo / Tr servo control device (not shown) to be used for servo control of a focusing / tracking actuator (not shown) for the objective lens 6, and for the recording medium 2. The laser light is controlled to properly track on the track in the focused state.

Further, a monitor element 13 for receiving a part of the light emitted from the semiconductor laser 3 via the mirror 11 and the detection lens 12 is provided. A power monitor signal obtained by current-voltage converting / amplifying a monitor current proportional to the light emission power of the semiconductor laser 3 detected by the monitor element 13 by the IV amplifier 14 is input to the system controller 10 and used for APC control or the like. .

In such a basic configuration, when reproducing information, the LD driving device 15 drives the semiconductor laser 3 to emit light with reproduction power (read power) Pr, and the light of the reproduction power from the semiconductor laser 3 is emitted. The recording medium 2 is irradiated through the pickup optical system, and the reflected light is received by the light receiving element 8 through the optical pickup optical system and photoelectrically converted,
The IV amplifier 9 performs current / voltage conversion / amplification and reproduction signal (RF
Signal).

Furthermore, a part of the light emitted from the semiconductor laser 3 is incident on the monitor element 13, and a monitor current proportional to the light emission power is converted into a current voltage by the IV amplifier 14, and the power monitor signal is amplified. , APC control can be performed.

On the other hand, the recording operation will be described. Normal,
When information is recorded on a dye-based medium such as a DVD + R, as shown in FIG. 5, the peak power Pw corresponding to the peak level, the space level, and the bias power Pb are 2
Different types of power are required (in the present embodiment, the bottom level (bias level Pb) for multi-pulse light emission at the time of mark formation will be described as the same level as the space level. However, the bottom level and the space level are different from each other. Sometimes treated as a level).

When recording information, the host controller 2
Under the control of 1, the data encoder 22 and the LD waveform control circuit 23 generate a pulse control signal based on the recording data composed of the 8-16 modulation code, and the LD driving device 15 drives the driving current according to the pulse control signal. Due to
By driving the semiconductor laser 3 to emit light with a multi-pulse waveform as shown in FIG. 5C and irradiating the recording layer of the recording medium 2, recording marks are formed on the recording medium 2 to record information. .

The host controller 21 outputs a bias level current drive signal and a peak level current superimposition signal to the LD drive device 15 in order to control the space / peak power emission level.

The power monitor signal obtained from the IV amplifier 14 is used for long space data output (for example, 10T).
The power sample timing signal output from the host controller 21 to the above space data) is sampled / held by the sample / hold circuit 24 at the timing of H → L, and space level power control is performed.

The peak level power is supplied to the semiconductor laser 3 by superimposing the peak level current superposition signal calculated from the differential efficiency η of the semiconductor laser 3 on the space level drive current (bias level current drive signal). To do.

The RF signal from the IV amplifier 9 is sent to the host controller 21 via the data decoder 25.
In addition, the peak level / bottom level detection signal can be taken in via the peak / bottom detection circuit 26.

With such a configuration, in the present embodiment, the semiconductor laser 3 is in the focus-on state during the OPC operation (trial writing process) performed to optimize the recording power level prior to the original recording operation. Differential efficiency η
Is calculated and the light emission power during the recording operation is determined.

Therefore, first, the processing when the OPC operation is performed will be described with reference to FIG. When performing the trial writing, basically, the host controller 21 is performing the write operation (write gate signal = H), and the sector (DVD format 8-
In the case of 16 modulation codes, a sector synchronization signal is generated each time 1488 * 26 = 38688 channel clocks) is switched, and the peak level current superposition signal is updated every time the sector synchronization signal is generated to gradually change the light emission power. Change to.

After the recording in which the power is changed stepwise is finished, the recorded area is reproduced, the RF signal is sampled for each sector, and the RF signal is sampled by using the formula shown in the formula (2). The asymmetry (β) is calculated in the sector, and the power during the recording operation is determined by the calculated β. The value of β with the best recording quality is experimentally obtained in advance according to the type of the recording medium 2.

Here, in order to calculate the differential efficiency η before the recording operation, generally, the recording light emission is performed in the focus-off state and the recording level power is detected. The differential efficiency characteristics of the semiconductor laser 3 differ depending on whether it is on or off. Therefore, in the present embodiment, O
During PC operation, recording is performed with a constant light emission power for a predetermined period immediately before recording by changing the light emission power stepwise, and at this time, the light emission power is sampled to obtain the differential efficiency η.

In general, one OPC operation is often performed in a predetermined block unit because of easy handling of addresses, and in the DVD system, one ECC block = 16 sectors is often used. Therefore, as shown in FIG. 3, for example, of the 16 sectors, the first 6 sectors are recorded with a constant emission power, the emission power is sampled during this period, and the emission power is gradually increased in the remaining 10 sectors. Change it to make it a normal test writing.

Normally, however, as shown in FIG. 5C, multi-pulse light emission in which peak level / bottom level is alternately emitted during mark data recording, and the peak level is changed in such a light emission state. It is not realistic to sample. Therefore, as indicated by the K portion in FIG. 3, during light emission for calculating the differential efficiency η, light emission is performed in a single pulse state for a certain period to sample the peak level.
The timing of setting the single pulse state is when the long mark data is generated (for example, 10T mark or more). Further, the power sample timing signal becomes H at the time when the long space is generated during the normal recording operation, but when emitting light for calculating the differential efficiency η, it is set at H in conjunction with setting the long mark data to the single pulse state, and the peak level is reached. To sample. The differential efficiency η of the semiconductor laser 3 can be calculated from the peak bell sampled in this way and the light emission levels at two space levels sampled when a long space occurs.

Further, the differential efficiency η is calculated immediately before the trial writing operation, and the trial writing currents for the seventh and subsequent sectors are driven by the superimposed current calculated based on the obtained differential efficiency η, thereby performing the trial writing. It can sometimes emit light with accurate light emission power.

FIG. 4 is a schematic flow chart showing an example of processing control associated with the above OPC operation executed by the host controller 21 having a built-in CPU and the like. Since the processing control is performed when the OPC operation is executed, first, the OP
It is determined whether or not the C operation is executed (step S
1). When the OPC operation is executed, the block for trial writing this time is set in the PCA area and the sector N
o. Is initialized to 0 (S2). Then, in order to start the operation, the write gate signal is turned on (switched to the H level) (S3). At this time, the focus on state is set so that the focus actuator and the like also operate.

Then, a constant light emission level for calculating the differential efficiency is set, and the corresponding bias level current drive signal and peak level current superimposition signal are output to the LD drive device 15, whereby the semiconductor laser 3 is kept constant. The light is emitted with the light emission power (S4). At this time, the sector No. Is incremented by +1 (S5). Then, it is monitored whether or not the long mark data of 10T or more appears in the predetermined write data for trial writing (S6). When the long mark data appears (Y of S6), the multi-pulse emission waveform is obtained. Instead, light is emitted with a single pulse light emission waveform as shown by K in FIG. 3 (S7). The power sample timing signal is also switched to the H level in synchronization with the change to the single pulse light emission waveform (S8), and the peak power level in the single pulse light emission state is held by the sample hold circuit 24.
To detect. The peak level at this time is determined by switching the power sample timing signal to the L level (S9). The above process is not performed until the long mark data of 10T or more appears, and the multi-pulse light emission is simply repeated at a constant power level.

On the other hand, in order to detect the bottom level as well, it is monitored whether or not long space data of 10T or more has appeared in predetermined write data for trial writing (S1).
0), when long space data appears (S1
(Y of 0), the power sample timing signal is switched to the H level (S11), and the bottom power level is detected by the sample hold circuit 24. The bottom level at this time is determined by switching the power sample timing signal to the L level (S12).

Such processing is performed in the block 6
When the processing is repeated up to the sector (N in S13) and the processing for 6 sectors is completed (Y in S13), the peak level and the bottom level detected based on the long mark data and the long space data are used. The differential efficiency η of the laser 3 is calculated (S14). The processing of step S14 is executed as a function of the differential efficiency calculation means, and the processing of steps S4 to S14 is executed as a function of the differential efficiency calculation processing control means.

Subsequently, the calculated differential efficiency η is used to set the light emission power at the time of performing trial writing on the subsequent sector (S15), and the sector No. Is incremented by +1 (S16), and trial writing is performed on the sector according to a predetermined multi-pulse light emission waveform (S16).
17). This trial writing process is performed with the sector No. If 16 does not reach 16 (N in S18), the light emission power level is increased by a predetermined number of steps (S19), and the process is repeated. The processing of steps S15 to S19 is executed as a function of the trial writing means.

Finally, the sector No. When the trial writing up to 16 is executed (Y of S18), the write gate signal is turned off (switched to the L level) (S20), and the sector No. in the block is changed. The reproducing operation is performed for 7 to 16 (S21), and the light emitting power determination process for the original recording operation is performed thereafter (S22). The processing of step S22 is executed by the function of the power determining means.

In the present embodiment, a dye-based medium such as DVD + R is assumed and the case of binary light emission level of peak level / bias level as shown in FIG. 5 is described. The same can be applied to the case of using a three-valued light emission level of peak level / erase level / bias level as in the case of the phase change type medium shown.

[0062]

According to the first aspect of the present invention, the differential efficiency of the laser light source is also calculated in the focus-on state when performing the trial writing for determining the light emission power during recording prior to the recording of information. By doing so, the differential efficiency can be calculated under the same conditions as in the recording operation without affecting the original recording operation, and the emission power during recording can be accurately determined and controlled.

According to the second aspect of the invention, in the optical information recording apparatus according to the first aspect, the laser light source emits multi-pulses in accordance with a predetermined light emission rule based on at least a binary power level of a bias level and a peak level. The differential efficiency can be accurately calculated even in the method of recording information by irradiating the recording medium with laser light.

According to the third aspect of the invention, in the optical information recording apparatus according to the second aspect, it is not necessary to prepare a special area or the like for calculating the differential efficiency, and the differential efficiency is within the range of the original trial writing process. The calculation process and the trial writing process can be appropriately divided and executed.

According to the fourth aspect of the invention, in the optical information recording apparatus according to the third aspect, it is possible to perform trial writing with more appropriate light emission power using accurate differential efficiency in the trial writing stage. The determined emission power at the time of recording can be made more appropriate.

According to a fifth aspect of the present invention, in the optical information recording apparatus according to any one of the first to fourth aspects, the laser light source has a predetermined power level of at least a binary value of a bias level and a peak level. The differential efficiency can be accurately calculated also in a system in which information is recorded by irradiating the recording medium with laser light by emitting multi-pulses according to the light emission rule.

According to the invention described in claim 6, the invention described in claim 5 can be easily realized by using so-called long mark data.

[Brief description of drawings]

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

FIG. 2 is a block configuration diagram showing an internal configuration example of the system control device.

FIG. 3 is a waveform diagram showing a processing example during an OPC operation.

FIG. 4 is a schematic flowchart showing an example of processing control during OPC operation.

FIG. 5 is a waveform diagram showing an example of an optical waveform in the case of a dye-based medium.

FIG. 6 is a waveform diagram showing an example of an optical waveform in the case of a phase change medium.

FIG. 7 is a waveform diagram showing an example of an optical waveform in the case of CD-R.

FIG. 8 is an LD drive current-LD emission power characteristic diagram of a semiconductor laser.

[Explanation of symbols]

2 recording media 3 laser light source 13 Monitor element

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Claims (6)

[Claims] 1. A recording medium in which a laser light source is pulse-emitted according to information having a data length based on a predetermined recording modulation method according to a predetermined light emission rule of at least a binary power level of a bias level and a peak level. In an optical information recording device for recording information by irradiating a laser beam on the recording medium, prior to the recording of information, the emission power of the laser light source is changed in multiple steps with respect to a predetermined area on the recording medium, and a trial is performed. Test writing means for writing, a monitor element for outputting a current corresponding to the light emission power of the laser light source as a monitor signal, a laser light source of the laser light source based on the light emission power of the laser light source and the monitor signal obtained from the monitor element The differential efficiency calculation means for calculating the differential efficiency and the differential efficiency calculation processing by the differential efficiency calculation means focus the laser light source. Differential efficiency calculation processing control means that is caused to emit light in the ON state and is executed when trial writing is performed by the test writing means, and power that determines the light emission power during recording using the differential efficiency calculated by the differential efficiency calculation means. An optical information recording device comprising: a determining unit. 2. The differential efficiency calculation processing control means, at the time of trial writing by the trial writing means, changes the light emission power of the laser light source in multiple steps to perform a trial writing recording, and a constant light emission power for a predetermined period. 2. The optical information recording apparatus according to claim 1, wherein the recording operation is performed by the method described above, and the differential efficiency is calculated by the differential efficiency calculating means. 3. One test writing is performed for each block composed of a plurality of sectors, and the differential efficiency calculation processing control means performs a recording operation with a constant light emission power for a predetermined number of sectors in the block. In addition, the differential efficiency is calculated by the differential efficiency calculating means, and the trial writing means performs trial writing recording by changing the emission power of the laser light source in multiple steps for the remaining sectors in the block. The optical information recording apparatus according to claim 2, wherein 4. The test writing means performs the test writing for each sector with multi-step emission power determined based on the differential efficiency calculated immediately before the trial writing in the block. The optical information recording device described. 5. A multi-pulse light emission is performed as mark recording information as the predetermined recording modulation method,
When detecting the laser power of the laser light source at the time of calculating the differential efficiency immediately before trial writing, the differential efficiency calculation processing control means causes the peak level to emit light in a single pulse state for a predetermined period to detect the peak level of light emitting power. The optical information recording device according to any one of claims 1 to 4, wherein 6. The light according to claim 5, wherein the differential efficiency calculation processing control means emits light so that the peak level is in a single pulse state for a predetermined period when the data length is a predetermined length or more. Information recording device.