JP2004199818A - Optical pickup device and optical disk unit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical pickup device which can accurately and stably output a signal including information required for controlling light emitting power without increasing its manufacturing cost. <P>SOLUTION: The light emitting power of luminous flux emitted from a light source 51a is monitored by a power monitor means, the output signal of the power monitor means receives the prescribed band restriction by a band restriction means 75. In such a case, a signal including information about an average value of the light emitting power is outputted as a monitor signal by setting the band restriction means so that a high frequency component included in the output signal of the power monitor means is eliminated, and thus the light emitting power of luminous flux emitted from the light source can be stably monitored even if recording speed for recording information on an information recording medium 15 is increased. The optical pickup device therefore can accurately and stably output a signal including information required for controlling light emitting power without increasing its manufacturing cost. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an optical pickup device and an optical disc device, and more particularly, to irradiating a recording surface of an information recording medium with light and receiving reflected light from the recording surface and recording information on the information recording medium. The present invention relates to an optical disk device.
[0002]
[Prior art]
2. Description of the Related Art In recent years, personal computers (hereinafter, also referred to as “personal computers”) have been able to handle AV (Audio-Visual) information such as music and video as their functions have been improved. Since the amount of information of these AV information is very large, an optical disk such as a CD (compact disc) or a DVD (digital versatile disc) has attracted attention as an information recording medium. Optical disk devices have become popular as one of the peripheral devices of personal computers. In an optical disk device, recording or erasing of information is performed by irradiating a minute spot of a laser beam onto a recording surface of an optical disk on which a spiral or concentric track is formed, and information is reproduced based on reflected light from the recording surface. And so on. The optical disc device is provided with an optical pickup device as a device for irradiating the recording surface of the information recording medium with laser light and receiving light reflected from the recording surface.
[0003]
In general, an optical pickup device includes a light source that emits laser light at a predetermined light emission power (output), guides laser light emitted from the light source to a recording surface of an information recording medium, and transmits laser light reflected by the recording surface. An optical system for guiding to a predetermined light receiving position, a light receiving element disposed at the light receiving position, and the like are provided.
[0004]
In an optical disc, information is recorded by the length of each of a mark area and a space area having different reflectances and a combination thereof. Therefore, when recording information on the optical disc, the light emission power of the light source is controlled so that a mark area and a space area are formed at predetermined positions.
[0005]
One example of a write-once optical disc (hereinafter also referred to as "dye-type disc" for convenience) such as CD-R (CD-recordable), DVD-R (DVD-recordable), and DVD + R (DVD + recordable) containing an organic dye in the recording layer is an example. As shown in FIG. 10A, when forming the mark area M in the write data MD, the emission power LP is increased (Pw in FIG. 10A) to heat and melt the dye, and The substrate part that has been altered or deformed. On the other hand, when the space region S is formed, the light emission power LP is set to be as small as that during reproduction (Pr in FIG. 10A) so that the substrate is not deteriorated or deformed. As a result, the reflectance in the mark area is lower than that in the space area. Such a method of controlling the light emission power is also called a single pulse recording method. Note that the light emission power when forming the mark area is also called peak power (or recording power), and the light emission power when forming the space area is also called bias power. That is, it has two types of emission power.
[0006]
In addition, a rewritable optical disc such as a CD-RW (CD-rewritable), a DVD-RW (DVD-rewritable), and a DVD + RW (DVD + rewritable) including a special alloy in a recording layer (hereinafter, also referred to as a “phase-change disc” for convenience). In (2), when forming the mark area, the special alloy is heated to the first temperature and then rapidly cooled to be in an amorphous state. On the other hand, when forming the space region, the special alloy is heated to a second temperature (<first temperature) and then gradually cooled to be in a crystalline state. Thereby, the reflectance is lower in the mark area than in the space area. In this case, as shown in FIG. 10B as an example, in order to remove the influence of heat storage, the light emission power for forming the mark area may be divided into a plurality of pulses (multi-pulse). Is being done. Such a control method of the light emission power is also called a multi-pulse recording method. In this multi-pulse recording method, the rule of making the light emission power at the time of forming a mark area multi-pulse is called a recording strategy. In the recording strategy, the light emission power Pw at the time of heating is also called peak power (or recording power), the light emission power Pr at the time of cooling is also called bias power, and the light emission power Pe at the time of forming a space area is erase power (or erase power). ). That is, it has three types of emission power. With the increase in recording speed, even for a dye-type disc, for example, in a DVD-type optical disc (DVD-R, DVD + R, etc.), as shown in FIG. Has been proposed. However, in this case, the light emission power at the time of cooling in the recording strategy is the same as the light emission power at the time of forming the space area. That is, there are two types of light emission power, peak power Pw and bias power Pr.
[0007]
Usually, a light source such as a semiconductor laser is a current drive type, and its light emission power is controlled by a current (drive current) supplied from a driver. The relationship between the drive current and the light emission power is called “IL characteristic”. In general, since a part of the drive current is converted into heat in the light source, the temperature of the light source gradually increases during use, and the IL characteristics may change. That is, the emission power fluctuates even when the drive current is constant. Therefore, during recording, so-called APC (Automatic Power Control) is performed, which monitors the light emission power of the light beam emitted from the light source and suppresses the fluctuation of the light emission power. However, in recent years, with the increase in recording speed, the pulse width has become extremely short, and in particular, the monitoring accuracy of peak power has been reduced. Therefore, several methods and apparatuses for accurately monitoring peak power have been proposed (for example, see Patent Documents 1 and 2).
[0008]
[Patent Document 1]
JP-A-11-213429
[Patent Document 2]
Japanese Patent Application Laid-Open No. H11-134692
[0009]
[Problems to be solved by the invention]
However, in the optical disk devices disclosed in Patent Documents 1 and 2, a plurality of partial pulses in a multi-pulsed recording signal are changed to one pulse to increase the pulse width, thereby increasing the peak power. Because of the improved monitor accuracy, the amorphization of the special alloy becomes insufficient and the recording quality may be degraded.
[0010]
Also, for example, in an optical disk device built in a notebook-type personal computer, the optical pickup device moves with the loading / unloading of the optical disk, and the layout between the optical pickup device and the signal processing circuit board is limited. The length of the signal cable may be longer than that of an optical disk device built in a desktop personal computer, for example. In an optical disk device compatible with high-speed recording, a wideband amplifier is generally used as an amplifier for amplifying a signal (monitor signal) output from a light receiving element (FSPD) for receiving a monitor light beam. The operation of this broadband amplifier becomes unstable when the signal cable becomes long and the so-called capacitive load increases, for example, ringing may occur, or in the worst case, oscillation may occur. As a result, the monitoring accuracy of the light emission power may be reduced, and the recording quality may be deteriorated.
[0011]
The present invention has been made under such circumstances, and a first object of the present invention is to accurately and stably output a signal including information necessary for controlling the emission power without increasing the cost. It is an object of the present invention to provide a possible optical pickup device.
[0012]
It is a second object of the present invention to provide an optical disk apparatus capable of performing high-quality recording stably at high speed.
[0013]
[Means for Solving the Problems]
The invention according to claim 1 is an optical pickup device that irradiates a recording surface of an information recording medium with light and receives reflected light from the recording surface, the light source comprising: a light source; An optical system that condenses light on a recording surface and guides a return light beam reflected by the recording surface to a predetermined light receiving position; a photodetector disposed at the light receiving position; and a light emission power of a light beam emitted from the light source An optical pickup device comprising: a power monitoring means for monitoring a frequency band; and a band limiting means for performing a predetermined band limitation on an output signal of the power monitoring means.
[0014]
According to this, the luminous flux of the light beam emitted from the light source is monitored by the power monitoring means, and the output signal of the power monitoring means is subjected to a predetermined band limitation by the band limitation means. Therefore, for example, the band limiting unit is set so that the high frequency component included in the output signal of the power monitoring unit is limited. As a result, a signal including information on the average value of the light emission power is output as a monitor signal, and the light emission power of the light beam emitted from the light source is reduced even when the recording speed when recording information on the information recording medium is increased. Monitoring can be performed stably. Further, even if a wideband amplifier is used to amplify the output signal of the power monitor, for example, the influence of ringing or the like can be removed by the band limiter, so that a stable monitor signal can be output. Further, since the band limiting means can be easily constituted by inexpensive general-purpose parts, it is possible to suppress the rise in parts costs and working costs to an extremely low level. Therefore, it is possible to output a signal including information necessary for controlling the light emission power with high accuracy and stability without increasing the cost.
[0015]
In this case, as in the optical pickup device according to the second aspect, the band limiting unit may include a low-pass filter.
[0016]
According to a third aspect of the present invention, there is provided an optical disc apparatus for irradiating light onto a recording surface of an information recording medium to perform at least recording among information recording, reproduction, and erasing. An optical disc device comprising: an optical pickup device; and power correction means for correcting the emission power of the light source based on an output signal of the band limiting means.
[0017]
According to this, since the light emission power of the light source is corrected by the power correction unit based on the output signal of the band limiting unit in the optical pickup device according to claim 1 or 2, for example, information can be transferred to the information recording medium at high speed. Even in the case of recording, the emission power can be accurately and stably corrected. As a result, it is possible to stably perform high-quality recording at a high speed.
[0018]
According to a fourth aspect of the present invention, there is provided an optical disc apparatus for irradiating a recording surface of an information recording medium with light to perform at least recording among information recording, reproduction, and erasure, comprising: a light source; Power monitoring means for monitoring the emission power of the luminous flux; bandwidth limiting means for performing a predetermined bandwidth limitation on the output signal of the power monitoring means; output signal of the bandwidth limiting means and output signal of the power monitoring means. An optical disc device comprising: a selection unit for selecting any one of them; and a power correction unit for correcting the emission power of the light source based on an output signal of the selection unit.
[0019]
According to this, the luminous flux of the light beam emitted from the light source is monitored by the power monitoring means, and the output signal of the power monitoring means is subjected to a predetermined band limitation by the band limitation means. Then, one of the signals output from the band limiter and the power monitor is selected by the selector, and the light emission power of the light source is corrected by the power corrector based on the selected signal. Therefore, for example, when information is recorded on an information recording medium, the selecting means selects a signal from which the signal used for correcting the emission power can be extracted relatively stably and with high accuracy. It can be corrected well. As a result, it is possible to stably perform high-quality recording at a high speed.
[0020]
In this case, as in the optical disk device according to the fifth aspect, the band limiting unit may include a low-pass filter.
[0021]
In each of the optical disk devices according to the fourth and fifth aspects, as in the optical disk device according to the sixth aspect, the selecting unit selects an output signal of the band limiting unit when the recording speed is equal to or higher than a predetermined threshold. In the case where the recording speed is lower than the threshold value, the output signal of the power monitoring means may be selected.
[0022]
In each of the optical disk devices according to the fourth and fifth aspects, as in the optical disk device according to the seventh aspect, the selecting unit selects an output signal of the band limiting unit at a timing of forming a mark area, and selects a space area. The output signal of the power monitoring means can be selected at the timing of forming.
[0023]
In each of the optical disk devices according to the fourth and fifth aspects, as in the optical disk device according to the eighth aspect, the selection unit includes a changeover switch, and the output of the band limiting unit is controlled according to a setting state of the changeover switch. One of a signal and an output signal of the power monitoring means can be selected.
[0024]
In each of the optical disk devices according to the third to eighth aspects, as in the optical disk device according to the ninth aspect, the power correction unit is a first sample-hold unit that samples and holds at a timing of forming a space area, and a mark area. At least one of the second sample-and-hold means for sampling and holding at the timing of forming.
[0025]
In this case, as in the optical disk device according to claim 10, the power correction unit includes the first sample and hold unit, and corrects emission power based on an output signal of the first sample and hold unit. It can be.
[0026]
In this case, as in the optical disk device according to the eleventh aspect, the power correction unit may correct the light emission power when forming the space area.
[0027]
In the optical disk device according to the ninth aspect, as in the optical disk device according to the twelfth aspect, the power correction unit includes the second sample and hold unit, and based on an output signal of the second sample and hold unit. To correct the emission power.
[0028]
In this case, as in the optical disk device according to the thirteenth aspect, the power correction means can correct the light emission power when forming the mark area.
[0029]
In the optical disk device according to the ninth aspect, as in the optical disk device according to the fourteenth aspect, the power correction means includes the first sample and hold means and the second sample and hold means, The light emission power can be corrected based on the output signal of the means.
[0030]
In this case, as in the optical disk device according to claim 15, the power correction unit corrects the emission power when forming the space area based on the output signal of the first sample and hold unit, and The light emission power when forming the mark area can be corrected based on the output signal of the sample hold means.
[0031]
In each of the optical disk devices according to the third to fifteenth aspects, as in the optical disk device according to the sixteenth aspect, recording on the information recording medium is performed by a multi-pulse recording method, and the power correction means includes a peak power, At least one of the erasing power and the bias power may be corrected.
[0032]
In each of the optical disk devices according to the third to fifteenth aspects, as in the optical disk apparatus according to the seventeenth aspect, recording on the information recording medium is performed by a single-pulse recording method, and the power correction unit determines the peak power and the peak power. At least one of the bias powers can be corrected.
[0033]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a block diagram showing a schematic configuration of an optical disk device according to one embodiment of the present invention.
[0034]
The optical disk device 20 shown in FIG. 1 includes a spindle motor 22, an optical pickup device 23, a laser control circuit 24, an encoder 25, a motor driver 27, a reproduction signal processing circuit 28 for rotating and driving an optical disk 15 as an information recording medium. , A servo controller 33, a buffer RAM 34, a buffer manager 37, an interface 38, a ROM 39, a CPU 40, a RAM 41, and the like. Note that the arrows in FIG. 1 indicate typical flows of signals and information, and do not indicate all of the connection relationships of the respective blocks. The optical disk device 20 is assumed to be compatible with an information recording medium conforming to the standard of the CD system (CD-R, CD-RW, etc.) as an example. The user data is recorded on a CD-R by a single pulse recording method, and is recorded on a CD-RW by a multi-pulse recording method.
[0035]
The optical pickup device 23 is a device for irradiating the recording surface on which the spiral or concentric tracks of the optical disk 15 are formed with laser light and receiving the reflected light from the recording surface. The optical pickup device 23 includes a light source unit 51, a collimator lens 52, a first beam splitter 54, a second beam splitter 71, an objective lens 60, a first detection lens 58, as shown in FIG. A first light receiver 59 as a light detector, a second detection lens 72, a second light receiver 73, a first amplifier (AMP) 74a, a second amplifier (AMP) 74b, and a low-pass filter (LPF) 75 , A multiplexer (MUX) 76 as a selection means, a driving system (a focusing actuator, a tracking actuator, and a seek motor (all not shown)) and the like.
[0036]
The light source unit 51 includes a semiconductor laser 51a as a light source that emits a light beam having a wavelength of 780 nm. In the present embodiment, the direction in which the maximum intensity of the light beam emitted from the semiconductor laser 51a is emitted is the + X direction. The collimator lens 52 is disposed on the + X side of the light source unit 51, and converts a light beam emitted from the semiconductor laser 51a into substantially parallel light.
[0037]
The second beam splitter 71 is arranged on the + X side of the collimator lens 52, and branches a part of the light beam emitted from the semiconductor laser 51a as a monitor light beam in the −Z direction. The first beam splitter 54 is arranged on the + X side of the second beam splitter 71, and splits the return light beam from the optical disc 15 in the −Z direction. The objective lens 60 is disposed on the + X side of the first beam splitter 54, and focuses a light beam transmitted through the first beam splitter 54 on a recording surface of the optical disc 15.
[0038]
The first detection lens 58 is disposed on the −Z side of the first beam splitter 54, and receives the return light beam branched in the −Z direction by the first beam splitter 54 on a light receiving surface of the first light receiver 59. Focus on The first light receiver 59 includes a plurality of light receiving elements that output signals including wobble signal information, reproduction data information, focus error information, track error information, and the like, similarly to a normal optical disk device.
[0039]
The second detection lens 72 is disposed on the −Z side of the second beam splitter 71, and receives the monitoring light beam branched in the −Z direction by the second beam splitter 71 by the second light receiver 73. Focus on the surface. As the second light receiver 73, a normal light receiving element is used.
[0040]
The first amplifier 74a amplifies the output signal of the first light receiver 59 with a predetermined gain. The signal amplified here is output to the reproduction signal processing circuit 28. The second amplifier 74b amplifies the output signal of the second light receiver 73 with a predetermined gain. Note that the first amplifier 74a and the second amplifier 74b may be integrated. Each of the amplifiers is a wideband amplifier so that high-speed recording can be performed. The low-pass filter 75 removes a high-frequency component included in the output signal Samp of the second amplifier 74b. That is, the signal Slpf including the information on the averaged light emission power is output from the low-pass filter 75.
[0041]
The multiplexer 76 selects one of the output signal Samp of the second amplifier 74b and the output signal Slpf of the low-pass filter 75 based on the select signal SEL from the encoder 25, and outputs the selected signal as the monitor signal Smux. Output to Here, as an example, when the select signal SEL is “0” (low level), the output signal Samp of the second amplifier 74b is selected, and when the select signal SEL is “1” (high level), the low-pass filter 75 is selected. Output signal Slpf is selected. In other words, the multiplexer 76 has a role of an on / off switch of the low-pass filter 75.
[0042]
The operation of the optical pickup device 23 configured as described above will be briefly described. A light beam emitted from the semiconductor laser 51a (hereinafter also referred to as an “emitted light beam”) is converted into substantially parallel light by a collimating lens 52, A part thereof is branched in the −Z direction by the second beam splitter 71, and the rest enters the first beam splitter 54. The emitted light flux transmitted through the first beam splitter 54 is condensed as a minute spot on the recording surface of the optical disc 15 via the objective lens 60. The reflected light reflected on the recording surface of the optical disk 15 is converted into substantially parallel light by the objective lens 60 as a return light flux, and enters the first beam splitter 54. The return light beam branched in the −Z direction by the first beam splitter 54 is received by the first light receiver 59 via the first detection lens 58. A signal corresponding to the amount of received light is output from the first light receiver 59, and the signal is amplified by the first amplifier 74a and then output to the reproduction signal processing circuit 28. The emitted light beam branched in the −Z direction by the second beam splitter 71 is received by the second light receiver 73 via the second detection lens 72 as a monitor light beam. A signal corresponding to the amount of received light is output from the second light receiver 73, and the signal is amplified by the second amplifier 74b, and then, via a low-pass filter 75 or a low-pass filter, depending on the setting state of the multiplexer 76. The signal is output to the reproduction signal processing circuit 28 without passing through the signal 75.
[0043]
As shown in FIG. 3, the reproduction signal processing circuit 28 includes a first I / V amplifier 28a, a servo signal detection circuit 28b, a wobble signal detection circuit 28c, an RF signal detection circuit 28d, a decoder 28e, and a second I / V amplifier 28a. / V amplifier 28f, first sample and hold circuit 28g, second sample and hold circuit 28h, A / D converter 28i, and the like.
[0044]
The first I / V amplifier 28a converts a current signal, which is an output signal of the first amplifier 74a, into a voltage signal. The servo signal detection circuit 28b detects a servo signal (such as a focus error signal or a track error signal) based on the output signal of the first I / V amplifier 28a. The servo signal detected here is output to the servo controller 33. The wobble signal detection circuit 28c detects a wobble signal based on the output signal of the first I / V amplifier 28a. The RF signal detection circuit 28d detects an RF signal based on the output signal of the first I / V amplifier 28a.
[0045]
The decoder 28e extracts ATIP (Absolute Time In Pregroove) information and a synchronization signal from the wobble signal detected by the wobble signal detection circuit 28c. The ATIP information extracted here is output to the CPU 40, and the synchronization signal is output to the encoder 25. The decoder 28e performs demodulation processing, error correction processing, and the like on the RF signal detected by the RF signal detection circuit 28d, and then stores the reproduced information in the buffer RAM 34 via the buffer manager 37. When the reproduction information is music data, a signal from the decoder 28e is output to an external audio device or the like via a D / A converter (not shown).
[0046]
The second I / V amplifier 28f converts a current signal, which is an output signal of the multiplexer 76, into a voltage signal. The first sample-hold circuit 28g performs sampling / hold on the output signal of the second I / V amplifier 28f in synchronization with the timing signal ST1 from the CPU 40. The output signal of the first sample-and-hold circuit 28g is converted into a digital signal SP1 by the A / D converter 28i, and then is notified to the CPU 40. The second sample / hold circuit 28h performs sampling / holding on the output signal of the second I / V amplifier 28f in synchronization with the timing signal ST2 from the CPU 40. The output signal of the second sample-and-hold circuit 28h is converted to a digital signal SP2 by the A / D converter 28i, and then is notified to the CPU 40. In the present embodiment, as an example, each sample and hold circuit starts sampling in synchronization with the rise of the timing signal, and holds the input signal at that time in synchronization with the fall. Also, each sample and hold circuit does not need to be particularly high-speed compatible, and is composed of general-purpose components.
[0047]
Referring back to FIG. 1, the servo controller 33 generates a control signal for correcting a focus shift based on the focus error signal from the reproduction signal processing circuit 28, and generates a control signal for correcting the track shift based on the track error signal. I do. Each control signal generated here is output to the motor driver 27.
[0048]
The motor driver 27 drives each actuator of the optical pickup device based on each control signal from the servo controller 33. That is, tracking control and focus control are performed by the servo signal detection circuit 28b, the servo controller 33, and the motor driver 27. The motor driver 27 drives the spindle motor 22 and the seek motor of the optical pickup device based on an instruction from the CPU 40.
[0049]
The encoder 25 extracts the data stored in the buffer RAM 34 via the buffer manager 37 based on an instruction from the CPU 40, performs data modulation, adds an error correction code, and the like, and generates a write signal to the optical disk 15. At the same time, the write signal is output to the laser control circuit 24 in synchronization with the synchronization signal from the reproduction signal processing circuit 28. Further, the encoder 25 outputs a select signal SEL to the multiplexer 76 according to an instruction from the CPU 40.
[0050]
As shown in FIG. 4, the laser control circuit 24 includes a D / A converter 24a, a pulse adjustment circuit 24b, a drive current output circuit 24c, and the like. The D / A converter 24a converts the power signals Dp1, Dp2, and Dp3 from the CPU 40 into current signals Ip1, Ip2, and Ip3, respectively. As shown in FIGS. 5A and 5B, Ip1 is a current signal corresponding to the bias power Pr, Ip2 is a current signal corresponding to a difference between the peak power Pw and the bias power Pr, and Ip3 is a current signal corresponding to the erase power Pe. This is a current signal corresponding to the difference from the bias power Pr. FIG. 5A shows the case where the optical disk 15 is a CD-R, and FIG. 5B shows the case where the optical disk 15 is a CD-RW.
[0051]
Returning to FIG. 4, the pulse adjustment circuit 24b adjusts the pulse with respect to the write signal WD from the encoder 25 based on the pulse adjustment signal Spuls from the CPU 40, and also superimposes the flag signal EFM1 in accordance with the pulse-adjusted write signal. , EFM2, and outputs them to the drive current output circuit 24c. “0” or “1” is output as each superimposition flag signal.
[0052]
The drive current output circuit 24c supplies a drive current corresponding to each superimposition flag signal to the semiconductor laser 51a. Here, as an example, as shown in FIGS. 6A and 6B, when both EFM1 and EFM2 are “0”, the drive current output circuit 24c outputs Ip1 (hereinafter, “bias current”). ) Is the drive current Idrv, and when only EFM1 is “1”, Ip1 + Ip2 (hereinafter also referred to as “peak current”) is the drive current Idrv. When only EFM2 is “1”, Ip1 + Ip3 (hereinafter, also referred to as “erase current”) is set as the drive current Idrv. Here, neither EFM1 nor EFM2 becomes “1”. FIG. 6A shows a case where the optical disk 15 is a CD-R, and FIG. 6B shows a case where the optical disk 15 is a CD-RW.
[0053]
Returning to FIG. 1, the interface 38 is a bidirectional communication interface with a host (for example, a personal computer), and is a standard interface such as ATAPI (AT Attachment Packet Interface), SCSI (Small Computer System Interface) and USB (Universal Serial Bus). Compliant with
[0054]
The ROM 39 has a program area and a data area. In the program area, a program described by a code readable by the CPU 40 is stored. In the data area of the ROM 39, a conversion formula (hereinafter referred to as “power conversion formula” for convenience) for obtaining the light emission power from the output signal of each sample and hold circuit is stored. Further, the data area of the ROM 39 stores power information including optimum bias power, peak power and erase power (only for phase change type discs), and pulse information such as a recording strategy for each type of optical disc.
[0055]
The CPU 40 controls the operation of each unit according to a program stored in a program area of the ROM 39, and temporarily stores data and the like necessary for the control in the RAM 41.
[0056]
Here, the processing operation of the CPU 40 when the optical disk 15 is loaded at a predetermined position of the optical disk device 20 configured as described above will be described.
[0057]
When the loading of the optical disk 15 is detected, the optical disk 15 is rotated at a predetermined linear velocity (for example, 1 × speed), and whether the optical disk 15 is a dye type disk or a phase change type disk is detected based on the reflectance. Here, when the reflectance is high (for example, 65% or more), the disk is a dye-type disk (in this case, CD-R). When the reflectance is low (for example, about 20%), the phase-change disk (in this case, -RW).
[0058]
Next, the bias power corresponding to the detection result is output as a power signal Dp1 to the D / A converter 24a of the power control circuit. Then, information (identification information) for identifying the type of the optical disk 15 recorded at a predetermined position on the optical disk 15 is read, and the power information and the pulse information stored in the data area of the ROM 39 are read out based on the identification information. The power information and the pulse information optimum for the optical disk 15 are extracted by referring to the information. Note that power information and pulse information recorded at a predetermined position on the optical disk 15 may be used.
[0059]
Subsequently, based on the extracted power information, the power signals Dp1, Dp2, and Dp3 are output to the D / A converter 24a of the power control circuit. The power signal Dp3 is output only when the optical disk 15 is a phase change disk. Further, based on the extracted pulse information, it outputs a pulse adjustment signal Spuls to the pulse adjustment circuit 24b of the power control circuit. Then, the processing when the optical disk 15 is loaded ends.
[0060]
Next, a processing operation for recording data on the optical disk 15 using the optical disk device 20 will be briefly described. It is assumed that the above-described processing when the optical disk 15 is loaded has already been performed.
[0061]
Upon receiving the recording request command from the host, the CPU 40 outputs a control signal for controlling the rotation of the spindle motor 22 to the motor driver 27 based on the recording speed, and reproduces that the recording request command has been received from the host. Notify the signal processing circuit 28. Further, the CPU 40 instructs the buffer manager 37 to store the user data received from the host in the buffer RAM 34.
[0062]
The CPU 40 sets “0” or “1” to the select signal SEL via the encoder 25. Here, as an example, “0” is set when the recording speed is lower than a predetermined threshold, and “1” is set when the recording speed is higher than the predetermined threshold. Note that the threshold can be set to an arbitrary value from the host and changed to an arbitrary value, for example.
[0063]
When the rotation of the optical disk 15 reaches a predetermined linear velocity, tracking control and focus control are performed as described above. Note that the tracking control and the focus control are performed as needed until the recording process ends. Further, the reproduction signal processing circuit 28 extracts the ATIP information at every predetermined timing and notifies the CPU 40 of the extracted ATIP information.
[0064]
The CPU 40 outputs a signal for controlling the seek motor to the motor driver 27 based on the ATIP information so that the optical pickup device 23 is located at the designated writing start point.
[0065]
Upon receiving from the buffer manager 37 that the amount of user data stored in the buffer RAM 34 has exceeded a predetermined amount, the CPU 40 instructs the encoder 25 to create a write signal. Then, when the optical pickup device 23 reaches the writing start point, it notifies the encoder 25. Thus, the user data is recorded on the optical disk 15 via the encoder 25, the laser control circuit 24, and the optical pickup device 23. When all the user data from the host is recorded, the recording process ends.
[0066]
Next, a description will be given of emission power correction processing that is performed as needed during the recording of the user data.
[0067]
First, the case where the optical disc 15 is a CD-R and the designated recording speed is lower than the threshold will be described. Therefore, “0” is set to the select signal SEL.
[0068]
When the recording of the user data is started, the CPU 40 generates timing signals ST1 and ST2 in synchronization with the write signal, and outputs each to the corresponding sample-and-hold circuit. Here, as an example, as shown in FIG. 7A, a pulse signal for sampling and holding the signal level corresponding to the light emission power when forming the space region is used as the timing signal ST1 as the first sample and hold circuit 28g. And a pulse signal for sampling and holding the signal level corresponding to the light emission power when forming the mark area is output to the second sample and hold circuit 28h as the timing signal ST2.
[0069]
Since the select signal SEL is “0”, the multiplexer 76 selects the output signal Samp of the second amplifier 74b as an example, as shown in FIG. 7A, and generates the monitor signal Smux as a reproduction signal processing circuit. 28.
[0070]
The monitor signal Smux is converted into a voltage signal by the second I / V amplifier 28f, sampled and held by each sample and hold circuit, and then output to the CPU 40 via the A / D converter 28i. Here, the signal SP1 output from the A / D converter 28i includes information on the light emission power corresponding to the drive current Ip1, and the signal SP2 includes information on the light emission power corresponding to the drive current Ip1 + Ip2.
[0071]
The CPU 40 calculates the light emission power from the signal SP1 using the power conversion formula, and compares the light emission power with the bias power extracted from the ROM 39 (hereinafter, also referred to as “optimal bias power” for convenience). In this case, the current value corresponding to the difference is calculated based on the differential efficiency (LD efficiency) obtained in advance. Then, the CPU 40 corrects the current signal Ip1 from the calculation result, and outputs a power signal Dp1 corresponding to the corrected current signal Ip1. This makes it possible to make the light emission power when forming the space region substantially coincide with the optimum bias power.
[0072]
Further, the CPU 40 calculates the light emission power from the signal SP2 using the power conversion formula, compares the light emission power with the peak power extracted from the ROM 39 (hereinafter also referred to as “optimum peak power” for convenience), and determines whether the power is equal to or more than a predetermined value. If there is a difference, a current value corresponding to the difference is calculated based on the differential efficiency. Then, CPU 40 corrects current signal Ip2 based on the calculation result, and outputs power signal Dp2 corresponding to the corrected current signal Ip2. When the current signal Ip1 is corrected, it is determined whether or not the current signal Ip2 needs to be corrected in consideration of the correction. This makes it possible to make the light emission power when forming the mark area substantially coincide with the optimum peak power.
[0073]
Here, the current signal Ip2 may be modified by utilizing the fact that the light emission power and the drive current have a substantially linear relationship. For example, when the optimum bias power is 1 mW, the optimum peak power is 10 mW, and the differential efficiency is 20 mW / 100 mA, the current signal Ip2 is 45 mA (= (10-1) × 100/20). Therefore, the CPU 40 may output the power signal Dp2 corresponding to 45 mA. Thereby, the processing is simplified, and the processing can be speeded up.
[0074]
Next, a case where the optical disk 15 is a CD-R and the recording speed is equal to or higher than the threshold will be described. Therefore, "1" is set to the select signal SEL.
[0075]
When the recording of the user data is started, the CPU 40 sets the timing signals ST1 and ST2 to “1” (high level) as shown in FIG. 7B as an example. Note that the timing signals ST1 and ST2 remain "1" until the correction processing ends.
[0076]
Since the select signal SEL is “1”, the multiplexer 76 selects the output signal Slpf of the low-pass filter 75 and outputs it to the reproduction signal processing circuit 28 as the monitor signal Smux. That is, as shown in FIG. 7B, a signal including information about the light emission power that has been substantially averaged (hereinafter also referred to as “average power” for convenience) is output as the monitor signal Smux.
[0077]
The monitor signal Smux is converted into a voltage signal by the second I / V amplifier 28f, and is output to the CPU 40 via each sample and hold circuit and the A / D converter 28i. Here, each sample and hold circuit outputs the output signal of the second I / V amplifier 28f without holding it. Therefore, the signal SP1 and the signal SP2 output from the A / D converter 28i are the same as each other.
[0078]
The CPU 40 calculates the light emission power (in this case, the average power) from the signal SP1 or the signal SP2 using the power conversion formula. Further, the CPU 40 calculates an optimum average power (hereinafter, also referred to as “optimum average power”) from the optimum bias power, the optimum peak power, and the duty of the pulse in the write signal, and compares the calculated average power with the detected average power. As a result, if there is a difference equal to or greater than a predetermined value, at least one of the current signals Ip1 and Ip2 is corrected based on the difference and the duty. Then, the power signal is corrected according to the corrected current signal. This makes it possible to make the light emission power when forming the space area substantially match the optimum bias power, and make the light emission power when forming the mark area almost match the optimum peak power. In this case, each sample and hold circuit is substantially unnecessary.
[0079]
The case where the optical disk 15 is a CD-RW and the recording speed is lower than the threshold will be described. Therefore, “0” is set to the select signal SEL.
[0080]
When the recording of the user data is started, the CPU 40 generates the timing signal ST2 in synchronization with the write signal, and outputs the timing signal ST2 to the second sample and hold circuit 28h. Here, as an example, as shown in FIG. 8A, a pulse signal for sampling and holding the signal level corresponding to the erase power is output as the timing signal ST2.
[0081]
Since the select signal SEL is “0”, the multiplexer 76 selects the output signal Samp of the second amplifier 74b as an example, as shown in FIG. 8A, and generates the monitor signal Smux as a reproduction signal processing circuit. 28.
[0082]
The monitor signal Smux is converted into a voltage signal by the second I / V amplifier 28f, sampled and held by the second sample and hold circuit 28h, and then output to the CPU 40 via the A / D converter 28i. Here, the signal SP2 output from the A / D converter 28i includes information on the emission power corresponding to the drive current Ip1 + Ip3.
[0083]
The CPU 40 calculates the light emission power from the signal SP2 using the power conversion formula, and compares the light emission power with the erase power extracted from the ROM 39 (hereinafter, also referred to as “optimum erase power” for convenience). In this case, a current value corresponding to the difference is calculated based on the differential efficiency obtained in advance, and an optimum erase current is obtained. The CPU 40 calculates the optimum bias current and the optimum peak current from the optimum erase current and the duty of the pulse in the write signal. Then, the current signals Ip1, Ip2, and Ip3 are obtained from the optimum bias current, the optimum peak current, and the optimum erase current, and the power signals Dp1, Dp2, and Dp3 corresponding to the current signals are output. As a result, the bias power, the erase power, and the peak power can be made substantially equal to their optimum values. In this case, the first sample and hold circuit 28g is substantially unnecessary.
[0084]
Further, a case where the optical disc 15 is a CD-RW and the recording speed is equal to or higher than the threshold will be described. Therefore, the select signal SEL is set to “1”.
[0085]
When the data recording is started, the CPU 40 sets the timing signal ST2 to “1” (high level) as shown in FIG. 8B as an example. Note that the timing signal ST2 remains “1” until the emission power correction processing ends.
[0086]
Since the select signal SEL is “1”, the multiplexer 76 selects the output signal Slpf of the low-pass filter 75 as an example, and outputs the selected signal Slpf to the reproduction signal processing circuit 28 as the monitor signal Smux, as shown in FIG. Output. That is, a signal including information on the average power is output as the monitor signal Smux.
[0087]
The monitor signal Smux is converted into a voltage signal by the second I / V amplifier 28f, and is output to the CPU 40 via the second sample and hold circuit 28h and the A / D converter 28i. Here, the second sample and hold circuit 28h outputs the output signal of the second I / V amplifier 28f without holding it.
[0088]
The CPU 40 calculates the average power from the signal SP2 using the power conversion formula. Further, the CPU 40 calculates the optimum average power from the optimum bias power, the optimum erase power, the optimum peak power, and the duty of the pulse in the write signal, compares the calculated average power with the detected average power, and, as a result of the comparison, a value equal to or more than a predetermined value. If there is a difference, the current signal is corrected based on the difference and the duty. Then, a power signal is output according to the corrected current signal. As a result, the bias power, the erase power, and the peak power can be made substantially equal to their optimum values. In this case, each sample and hold circuit is substantially unnecessary.
[0089]
In addition, a brief description will be given of a processing operation when reproducing data recorded on the optical disk 15 using the optical disk device 20.
[0090]
When receiving the command of the reproduction request from the host, the CPU 40 outputs a control signal for controlling the rotation of the spindle motor 22 to the motor driver 27 based on the reproduction speed, and also notifies the motor driver 27 of the reception of the command of the reproduction request. The processing circuit 28 is notified. Further, the CPU 40 instructs the drive current output circuit 24c to use the bias current as the drive current.
[0091]
When the rotation of the optical disk 15 reaches a predetermined linear velocity, tracking control and focus control are performed as described above. Note that the tracking control and the focus control are performed as needed until the reproduction process ends. Further, the reproduction signal processing circuit 28 extracts the ATIP information at predetermined timings until the reproduction processing ends, and notifies the CPU 40 of the extracted ATIP information.
[0092]
The CPU 40 outputs a signal for controlling the seek motor to the motor driver 27 based on the ATIP information so that the optical pickup device 23 is located at the reading start point. Then, when the optical pickup device 23 reaches the reading start point, it notifies the reproduction signal processing circuit 28.
[0093]
Then, the reproduction signal processing circuit 28 detects the RF signal as described above, performs demodulation processing, error correction processing, and the like, and then stores it in the buffer RAM 34. The buffer manager 37 transfers the reproduced data stored in the buffer RAM 34 to the host via the interface 38 when the data is prepared as sector data.
[0094]
As is apparent from the above description, in the optical pickup device according to the present embodiment, the second beam splitter 71, the second detection lens 72, the second light receiver 73, and the second amplifier 74b are used. Power monitoring means is configured.
[0095]
In the optical disk device according to the present embodiment, a power correction unit is realized by the reproduction signal processing circuit 28, the CPU 40, and a program executed by the CPU 40. However, it goes without saying that the present invention is not limited to this. That is, the above-described embodiment is merely an example, and at least a part of each component realized by the processing according to the program by the CPU 40 may be configured by hardware, or all components may be configured by hardware. It is good.
[0096]
As described above, according to the optical pickup device 23 according to the present embodiment, a part of the light beam emitted from the semiconductor laser 51b is received by the second light receiver 73 and amplified by the second amplifier 74b. After that, the high-frequency component is removed by the low-pass filter 75. That is, a signal including information on the average value of the light emission power is output from the low-pass filter 75, and even if the recording speed is high, the light emission power of the light beam emitted from the semiconductor laser 51b can be stably monitored. Can be. Further, for example, even if ringing occurs in the second amplifier 74b, the influence can be removed by the low-pass filter 75, so that a stable monitor signal can be output. Further, the low-pass filter 75 can be easily formed with inexpensive general-purpose components. That is, it is possible to output a signal including information necessary for controlling the light emission power accurately and stably without increasing the cost.
[0097]
According to the optical disc device 20 of the present embodiment, when recording information on the optical disc 15 and the recording speed is lower than the predetermined threshold, the light emission of the semiconductor laser 51a is performed based on the output signal of the second light receiver 73. When power-related information is detected, and when the recording speed is equal to or higher than a predetermined threshold, information relating to the light-emitting power of the semiconductor laser 51a is detected based on the output signal of the low-pass filter 75. Can be accurately detected. Therefore, even when the IL characteristic of the semiconductor laser 51a changes, particularly at the time of high-speed recording, it is possible to always maintain the optimum light emission power, and as a result, recording with excellent recording quality is stably performed at high speed. It becomes possible.
[0098]
In the above-described embodiment, the case where the select signal SEL is set to “0” or “1” based on the recording speed has been described. However, the present invention is not limited to this. When the length of the signal cable between the optical pickup device 23 and the reproduction signal processing circuit 28 is longer than a predetermined length, the select signal SEL may be fixed to “1” in advance. In this case, for example, a dip switch may be provided so that the select signal SEL can be set from the outside. Alternatively, the select signal SEL may be set by the host. Further, a monitoring circuit that monitors the output signal Samp of the second amplifier 74b and sets the select signal SEL to “1” when the quality of the signal becomes equal to or lower than a predetermined level may be provided.
[0099]
In the above embodiment, the case where the select signal SEL is set in accordance with the recording speed has been described. However, the present invention is not limited to this. For example, as shown in FIG. It may be set to "1" and the select signal SEL may be set to "0" when forming a space area. This case will be described with reference to FIG. FIG. 9 shows a timing chart when the optical disk is a CD-RW.
[0100]
As shown in FIG. 9 as an example, the CPU 40 outputs, as a timing signal ST1, a pulse signal for sampling and holding a signal level corresponding to the light emission power when forming the space area, in synchronization with the write signal. A pulse signal for sampling and holding the signal level corresponding to the light emission power when forming the mark area is output as the timing signal ST2, and when forming the mark area, the select signal SEL is set to "1" and the space area is set. Is formed, the encoder 25 is instructed to set the select signal SEL to "0".
[0101]
The multiplexer 76 selects the signal Samp when the select signal SEL is “0”, selects the output signal Slpf when the select signal SEL is “1”, and outputs the selected signal to the reproduction signal processing circuit 28 as the monitor signal Smux. .
[0102]
The monitor signal Smux is converted into a voltage signal by the second I / V amplifier 28f, sampled and held by each sample and hold circuit, and then output to the CPU 40 via the A / D converter 28i. Here, the signal SP1 output from the A / D converter 28i includes information regarding the average power when forming the mark area, and the signal SP2 includes information regarding the emission power corresponding to the driving current Ip1 + Ip3.
[0103]
Then, the CPU 40 calculates the light emission power corresponding to the drive current Ip1 + Ip3 based on the signal SP2, and obtains an optimum erase current. Further, the CPU 40 calculates the average power when forming the mark area based on the signal SP1, calculates the optimum average power from the optimum bias power, the optimum peak power, and the duty of the pulse in the write signal, and performs the same as described above. Correct the current signals Ip1 and Ip2. Further, the current signal Ip3 is corrected based on the optimum erase current obtained from the signal SP2 and the corrected current signal Ip1. Then, it outputs power signals Dp1, Dp2, and Dp3 according to the corrected current signals Ip1, Ip2, and Ip3, respectively. As a result, the bias power, the erase power, and the peak power can be made substantially equal to their optimum values. Even when the optical disk 15 is a CD-R, the emission power can be corrected in substantially the same manner.
[0104]
In the above embodiment, the case where two sample hold circuits are provided has been described. However, the present invention is not limited to this. For example, when the optical disk 15 is a CD-R and only the bias power or the peak power is detected, the sample hold circuit is provided. The number of circuits may be one. Thereby, cost reduction can be promoted.
[0105]
In the above embodiment, the case where the multiplexer 76 is mounted on the optical pickup device has been described. However, the present invention is not limited to this. For example, a processing circuit that performs the same processing as the multiplexer 76 may be added to the reproduction signal processing circuit 28. good.
[0106]
Further, in the above embodiment, when it is almost certain that the recording speed is always equal to or higher than the predetermined threshold, the output signal of the low-pass filter 75 may be set to be always output to the reproduction signal processing circuit 28. . In this case, the multiplexer 76 need not be provided.
[0107]
In the above embodiment, the case where the low-pass filter 75 is mounted on the optical pickup device has been described. However, the present invention is not limited to this. For example, the low-pass filter 75 and the multiplexer 76 are different from the optical pickup device. They may be arranged separately. However, it is preferable that the distance between the second amplifier 74b and the low-pass filter 75 is as short as possible.
[0108]
Further, in the above embodiment, the case where the second beam splitter 71 is disposed between the collimator lens 52 and the first beam splitter 54 in order to extract the monitoring light flux has been described. However, the present invention is not limited to this. For example, of the light beams emitted from the semiconductor laser 51a, the light beams that are not captured by the collimator lens 52 may be branched by a reflection mirror or the like. In short, it is only necessary to obtain information on the light emission power of the light beam emitted from the semiconductor laser 51a. It is not always necessary to split the emitted light beam, and a part of the light beam emitted from the semiconductor laser 51a may be directly received by the second light receiver 73.
[0109]
Further, in the above-described embodiment, the case where the optical disc apparatus is compatible with a CD-based information recording medium has been described. However, the present invention is not limited to this. good. In short, any optical disk device that records information by pulsing laser light from a light source may be used.
[0110]
Further, in the above embodiment, the optical disk device capable of recording and reproducing information has been described. However, the present invention is not limited to this, and any optical disk device capable of recording information, at least among information recording, reproducing, and erasing, may be used. . Further, the optical disk device may be a built-in personal computer type or an external stationary type. Further, in the case of a built-in type, the personal computer may be a desktop type or a notebook type.
[0111]
Further, in the above embodiment, the case where there is one light source has been described, but the present invention is not limited to this. For example, a light source for CD and a light source for DVD may be provided. Further, a light source that emits a light beam having a wavelength of 405 nm may be provided together with the light source for CD and the light source for DVD, or instead of any one of the light sources. That is, an optical disk device that supports a plurality of types of information recording media may be used.
[0112]
【The invention's effect】
As described above, according to the optical pickup device of the present invention, it is possible to accurately and stably output a signal including information necessary for controlling the emission power without increasing the cost. is there.
[0113]
Further, according to the optical disk device of the present invention, there is an effect that recording with excellent recording quality can be stably performed at a high speed.
[Brief description of the drawings]
FIG. 1 is a block diagram illustrating a configuration of an optical disc device according to an embodiment of the present invention.
FIG. 2 is a diagram for explaining a detailed configuration of an optical pickup device in FIG. 1;
FIG. 3 is a block diagram for explaining a detailed configuration of a reproduction signal processing circuit in FIG. 1;
FIG. 4 is a block diagram for explaining a detailed configuration of a laser control circuit in FIG. 1;
FIG. 5A is a diagram for explaining a driving current in a single pulse recording system, and FIG. 5B is a diagram for explaining a driving current in a multi-pulse recording system.
FIG. 6A is a diagram for explaining a superimposition flag signal in a single pulse recording system, and FIG. 6B is a diagram for explaining a superimposition flag signal in a multi-pulse recording system.
FIGS. 7A and 7B are timing charts for explaining a timing signal of a sampling circuit for acquiring a monitor signal of a light emission power and an output signal of a multiplexer in a single pulse recording method, respectively. It is a chart.
FIGS. 8A and 8B are timing charts for explaining a timing signal of a sampling circuit for obtaining a monitor signal of a light emission power and an output signal of a multiplexer in a multi-pulse recording method, respectively. It is a chart.
FIG. 9 is a timing chart for explaining an example different from FIG. 8B in the multi-pulse recording method.
FIGS. 10A to 10C are timing charts for explaining differences in light emission pulses depending on recording methods.
[Explanation of symbols]
15 optical disk (information recording medium), 20 optical disk device, 23 optical pickup device, 28 reproduction signal processing circuit (part of power correction means), 28 g first sample hold circuit (first sample hold means) ), 28h... A second sample and hold circuit (second sample and hold means), 40... A CPU (part of power correction means), 75... A low-pass filter, and 76.

Claims (17)

An optical pickup device that irradiates light to a recording surface of an information recording medium and receives reflected light from the recording surface,
A light source;
An optical system for converging a light beam emitted from the light source on the recording surface and guiding a return light beam reflected on the recording surface to a predetermined light receiving position;
A light detector arranged at the light receiving position;
Power monitoring means for monitoring the emission power of the light beam emitted from the light source;
An optical pickup device comprising: a band limiting unit configured to perform a predetermined band limitation on an output signal of the power monitoring unit. The optical pickup device according to claim 1, wherein the band limiting unit includes a low-pass filter. An optical disc device that irradiates light onto a recording surface of an information recording medium and performs at least recording of information recording, reproduction, and erasing,
An optical pickup device according to claim 1 or 2;
An optical disc device comprising: power correction means for correcting the light emission power of the light source based on the output signal of the band limiting means. An optical disc device that irradiates light onto a recording surface of an information recording medium and performs at least recording of information recording, reproduction, and erasing,
A light source;
Power monitoring means for monitoring the emission power of the light beam emitted from the light source;
Band limiting means for performing a predetermined band limitation on an output signal of the power monitoring means;
Selecting means for selecting one of the output signal of the band limiting means and the output signal of the power monitoring means;
An optical disc device comprising: power correction means for correcting the light emission power of the light source based on the output signal of the selection means. The optical disk device according to claim 4, wherein the band limiting unit includes a low-pass filter. The selector selects the output signal of the band limiting unit when the recording speed is equal to or higher than a predetermined threshold, and selects the output signal of the power monitor unit when the recording speed is lower than the threshold. The optical disk device according to claim 4. 6. The apparatus according to claim 4, wherein the selection unit selects an output signal of the band limiting unit at a timing of forming a mark area, and selects an output signal of the power monitoring unit at a timing of forming a space area. An optical disc device according to claim 1. 6. The apparatus according to claim 4, wherein the selection unit includes a changeover switch, and selects one of an output signal of the band limiting unit and an output signal of the power monitor unit according to a setting state of the changeover switch. An optical disc device according to claim 1. The power correction unit includes at least one of a first sample and hold unit that samples and holds at a timing of forming a space region and a second sample and hold unit that samples and holds at a timing of forming a mark region. Item 10. The optical disk device according to any one of items 3 to 8. 10. The optical disk apparatus according to claim 9, wherein the power correction unit includes the first sample and hold unit, and corrects a light emission power based on an output signal of the first sample and hold unit. 11. The optical disk device according to claim 10, wherein the power correction unit corrects light emission power when forming a space area. 10. The optical disk device according to claim 9, wherein the power correction unit includes the second sample and hold unit, and corrects a light emission power based on an output signal of the second sample and hold unit. 13. The optical disk device according to claim 12, wherein the power correction unit corrects light emission power when forming a mark area. 10. The power correction unit according to claim 9, wherein the power correction unit includes the first sample and hold unit and the second sample and hold unit, and corrects emission power based on an output signal of each of the sample and hold units. Optical disk device. The power correction means corrects the emission power when forming a space area based on an output signal of the first sample and hold means, and forms a mark area based on an output signal of the second sample and hold means. 15. The optical disk device according to claim 14, wherein the light emission power at that time is corrected. Recording on the information recording medium is performed by a multi-pulse recording method,
The optical disk device according to claim 3, wherein the power correction unit corrects at least one of a peak power, an erase power, and a bias power. The recording on the information recording medium is performed by a single-pulse recording method, and the power correction unit corrects at least one of a peak power and a bias power. Optical disk device.

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