JP2014059931A - Optical recording device and optical recording method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To speed up data recording including verification operation on an optical disk.SOLUTION: An optical recording device that performs recording on a multilayer optical disk 11 includes: a first optical pickup 32 that is capable of recording data on a recording layer 113 of the multilayer optical disk 11; a second optical pickup 32a that is capable of reading out data recorded on the multilayer optical disk 11; and a controller 83 that performs control of reading out the recorded data by using the second optical pickup 32a during recording of the data by using the first optical pickup 32 and performing verification. It is possible to generate a period in which recording on the recording layer of the multilayer optical disk and verification of the recorded data are simultaneously performed and to speed up recording including verification.

Description

  The present invention relates to an optical recording apparatus and an optical recording method capable of performing recording on an optical disc.

  For the purpose of increasing the capacity of an optical disc such as a DVD (Digital Versatile Disk) or a Blu-ray Disc (registered trademark), the recording layer is made multi-layered. Along with the increase in the number of recording layers, there is also known a system in which track king control at the time of recording or reproducing data on a recording layer is performed using a guide track provided in a layer different from the recording layer. For example, tracking control is performed using light (guide light) having a wavelength (red) of 650 nm to 680 nm on a guide track layer provided with a guide track having a groove structure, and one of the plurality of recording layers is recorded. In addition, there is an optical disk drive that performs recording using light (recording / reproducing light) having a wavelength (blue) of 390 nm to 420 nm.

  Also, in an optical disc drive capable of recording on an optical disc, in order to ensure the reliability of the recorded data, after the data is recorded on the optical disc with an optical pickup, the recorded data is reproduced, and the recording source data and reproduced data are A verify operation is performed to verify whether or not the data has been correctly recorded (see Patent Document 1).

JP 2006-155888 A

  Normally, in the verify operation, after data recording on the optical disc is completed, it is necessary to return the optical pickup to a position corresponding to the first track on which the data is recorded, and then read and reproduce the data. Therefore, as a result, the optical pickup traces the current recording position on the disk at least twice, which is one of the factors that hinder the overall recording time. This problem becomes conspicuous as the recording capacity of the medium increases as in a multilayer optical disc.

  In view of the circumstances as described above, an object of the present invention is to provide an optical recording apparatus and an optical recording method capable of speeding up recording including a verify operation.

  In order to achieve the above object, an optical recording apparatus according to an aspect of the present invention records on an optical disc having one or more recording layers capable of recording information and a guide layer provided with a guide track for tracking. A first optical pickup capable of recording data on the recording layer of the optical disc; and a second optical pickup capable of reading the recorded data from the optical disc; And a controller that controls to read the recorded data using the second optical pickup and perform verification during the recording of the data using the first optical pickup.

  The optical recording apparatus according to the present invention includes a first optical pickup and a second optical pickup that can operate independently from each other, and the control unit records data during recording of data using the first optical pickup. The data is read using the second optical pickup, and control is performed so as to perform verification. That is, according to the present invention, it is possible to generate a period in which recording on the recording layer of the multilayer optical disc and verification of the recording data are simultaneously performed, and recording including the verify operation can be speeded up.

  In the optical recording apparatus according to the present invention, the first optical pickup includes a recording optical system for performing recording by irradiating the recording layer of the optical disc with a recording laser beam, and the guiding laser beam. A guide optical system that irradiates the guide layer of the optical disc and outputs a first signal corresponding to the return light, and the second optical pickup irradiates the recording layer of the optical disc with a laser beam for reproduction. And a first reproducing optical system that outputs a second signal corresponding to the return light, and the optical recording apparatus further includes the first optical output from the guide optical system of the first optical pickup. A first tracking processing unit that performs processing related to tracking of the first optical pickup using a signal, and the second signal output from the first reproducing optical system of the second optical pickup are used. Te may be one which includes a second tracking processing unit for performing processing relating to the tracking of the second optical pickup.

  When the data recorded on the recording layer of the multilayer optical disc is reproduced by the second optical pickup, tracking is performed on the recording mark of the recording layer, thereby tracking the guide track of the guide layer. Compared to the case, for example, tracking error due to tilt is reduced, so that tracking can be performed with high accuracy, and the frequency of read retries during reproduction can be suppressed. Thereby, the time from the start of recording to the end of verification can be further shortened.

  The optical recording apparatus according to the present invention further includes a characteristic detector that detects a physical characteristic value of the return light based on the second signal output from the reproducing optical system of the second optical pickup. The control unit may perform OPC (Optimized Power Control) based on the detected physical characteristic value.

In the optical recording apparatus according to the present invention, the first optical pickup irradiates the recording layer of the optical disc with a reproducing laser beam and outputs a third signal corresponding to the return light. And the control unit controls to perform reproduction using the second reproduction optical system of the first optical pickup and the first reproduction optical system of the second optical pickup simultaneously. It may be.
Thereby, the transfer rate at the time of reproduction | regeneration can be raised significantly.

  In the optical recording apparatus according to the present invention, the control unit is configured to perform the first optical pickup and the previous optical signal based on the second signal output from the first reproduction optical system of the second optical pickup. The tilt correction of the optical pickup 2 may be performed.

  An optical recording method according to another aspect of the present invention is a method for recording on a multilayer optical disc having one or more recording layers capable of recording information and a guide layer provided with a guide track for tracking. The data is recorded on the recording layer of the optical disc by the first optical pickup, and the recorded data is reproduced during the recording by the optical pickup operable independently of the first optical pickup. Then, verify is performed.

  As described above, according to the present invention, it is possible to speed up recording including a verify operation.

1 is a diagram showing an optical recording system according to an embodiment of the present invention. It is a figure which shows the accommodation form of the disc cartridge in the optical recording system of FIG. 1, and the several multilayer optical disk in this. It is a figure which shows the structure of the disk cartridge in the optical recording system of FIG. 1, a multilayer optical disk, and a drive unit. It is sectional drawing which shows the structure of a multilayer optical disk. FIG. 5 is a diagram illustrating a configuration of a region divided by radial positions of a guide layer and a recording layer in the multilayer optical disc of FIG. It is a figure which shows the structure of the disk drive in the optical recording system of FIG. 1 centering on a 1st optical pick-up. It is a figure which shows the structure of the disk drive in the optical recording system of FIG. 1 centering on a 2nd optical pick-up. It is a figure for demonstrating the mechanism of the verify operation | movement in the disk drive of FIG. It is a figure explaining the modification 1 of this embodiment. It is a figure explaining the modification 2 of this embodiment.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
<First Embodiment>
FIG. 1 is a diagram showing an optical recording system according to the first embodiment of the present invention.

FIG. 1 is a diagram showing the overall configuration of an optical recording system.
The optical recording system 1 includes a disk cartridge 10, a disk transport mechanism 20, a drive unit 30, a RAID controller 40, and a host device 50. Details of each will be described below.

[Disc cartridge 10]
The disk cartridge 10 is a unit in which a multilayer optical disk 11 as a plurality of multilayer optical recording media is individually detachably accommodated.

  FIG. 2 is a view showing a storage form of the disk cartridge 10 and a plurality of multilayer optical disks 11 therein. As the accommodation form of the plurality of multilayer optical discs 11 in the disc cartridge 10, flat stacking, vertical alignment, and the like are assumed. In any case, it is preferable that a certain gap is provided between adjacent multilayer optical discs 11 so that the multilayer optical disc 11 can be smoothly inserted into and removed from the disc cartridge 10. The shape of the disk cartridge 10 is assumed to be, for example, a rectangular parallelepiped shape or a cylindrical shape from the viewpoint of handling by the user and the storage efficiency of the multilayer optical disk 11. In the example of FIG. 2, a rectangular parallelepiped disk cartridge 10 in which a plurality of multilayer optical disks 11 are accommodated in a flat stack is used.

FIG. 3 is a diagram showing the configuration of the disk cartridge 10, the multilayer optical disk 11, and the drive unit 30.
At least one side surface of the disk cartridge 10 is provided with an opening 110 for inserting and removing the multilayer optical disk 11 and a door (not shown) for opening and closing the opening 110. The door is opened and closed in conjunction with the operation of loading / unloading the multilayer optical disk 11 from / to the disk cartridge 10 by the disk transport mechanism 20, and is closed at other times. The plurality of multilayer optical disks 11 accommodated in the disk cartridge 10 are taken out by the disk transport mechanism 20 and selectively transported (loaded) to the plurality of disk drives 31 in the drive unit 30.

  In the present invention, the configuration of the disk cartridge 10 is not limited to that shown in FIG. Various modifications such as the shape of the disk cartridge 10, the number and position of the openings, the presence / absence of a door, and the accommodation form of a plurality of multilayer optical disks 11 are possible.

[Multilayer optical disc 11]
The multilayer optical disk 11 accommodated in the disk cartridge 10 is assumed to be a so-called guide layer separation type multilayer optical disk in which the guide layer and the recording layer are separated into separate layers.

FIG. 4 is a cross-sectional view showing a configuration of a multilayer optical disc 11 that is a guide layer separation type multilayer optical disc.
The multilayer optical disc 11 has a guide layer 112 and a plurality of recording layers 113. In the example of the multilayer optical disk 11 in FIG. 9, the number of recording layers 113 is “4”. An intermediate layer 114 having optical transparency is interposed between the guide layer 112 and the recording layer 113 closest to the guide layer 112 and between the adjacent recording layers 113. These layers are the protective layer 115, the recording layer 113, the intermediate layer 114, the recording layer 113, the intermediate layer 114, the recording layer 113, the intermediate layer from the side on which the recording / reproducing light R1 and the guide light R2 from the optical pickup 32 are incident. The layer 114, the recording layer 113, the intermediate layer 114, and the guide layer 112 are stacked in this order.
Each recording layer 113 is distinguished from the opposite side of the laser beam incident side (guide layer side) as “recording layer L0”, “recording layer L1”, “recording layer L2”, and “recording layer L3”. To do.

  A guide track 121 having a land / groove structure is spirally or concentrically provided on the surface of the guide layer 112 facing the recording layer 113. In the guide track 121, physical address information is formed by wobbling or pit rows on the side wall surface. The guide track 121 is formed with a track pitch (for example, 0.64 μm) corresponding to red laser light used for recording / reproduction of a DVD (Digital Versatile Disk), for example. The average pitch between the land and the groove is, for example, 0.32 μm. Hereinafter, the laser beam of the red laser beam is referred to as “guide light”.

  In the optical recording system 1 of the present embodiment, for example, the push-pull method (PP: Push-Pull), the differential push-pull method (DPP: Differential Push-Pull), and the three beams in each of the land and groove of the guide track 121. Tracking control is performed by law. By performing tracking control in each of the land and groove of the guide track 121, information can be recorded on the recording layer 113 at a track pitch of 0.32 μm.

  The recording layer 113 is a layer on which information is recorded at a track pitch (0.32 μm) corresponding to blue laser light used for recording / reproducing of a Blu-ray Disc (registered trademark), for example. Hereinafter, this blue laser light is referred to as “recording / reproducing light” or “recording light”. The recording layer 113 is composed of, for example, a light absorption layer and a reflection layer. As the light absorption layer, organic dyes such as cyanine dyes and azo dyes, and inorganic materials such as Si, Cu, Sb, Te, and Ge are used. When the target recording layer 113 in the multilayer optical disc 11 is irradiated with the recording light, the reflectance of the area irradiated with the recording light is changed, and the area where the reflectance is changed is formed as a recording mark. Information is recorded in layer 113.

  The tracking control and the acquisition of the physical address and the reference clock at the time of recording information on the recording layer 113 are performed by using the guide track 121 of the guide layer 112. Therefore, the recording track 113 has a guide track having a land / groove structure. 121 is not necessary. Therefore, the surface of the recording layer 113 may be flat.

FIG. 5 is a diagram showing a configuration of regions divided by radial positions of the guide layer 112 and the recording layer 113 in the multilayer optical disc 11.
The guide layer 112 and the recording layer 113 are divided into the lead-in area, the data area, and the lead-out area in common from the inner peripheral side depending on the position in the radial direction.

In the lead-in area of the guide layer 112, management information unique to the multilayer optical disk 11 is recorded in advance by wobbling of guide tracks or pit rows provided in lands and grooves.
The management information unique to the multilayer optical disc 11 includes, for example, recommended information such as the number of recording layers, recording method, recording linear velocity, laser power and laser drive pulse waveform during recording / reproduction, position information of the data area, position of the OPC area Contains information. The OPC area is provided, for example, on the inner peripheral side of the lead-in area.
Also, in the lead-in area of the guide layer 112, the position information (disk radius position) of each recording layer 113 is recorded in advance by wobbling of the guide track or pit rows provided in the land and groove. Has been.

  In the data area of the guide layer 112, physical address information assigned to the data area is recorded in advance by wobbling of the guide track 121 or prepit rows provided in lands and grooves.

  In the lead-out area of the guide layer 112, the same information as the information recorded in the lead-in area may be recorded in advance by wobbling of the guide track 121 or a prepit row provided in the land and groove. Good.

  The lead-in area of the recording layer 113 (hereinafter referred to as “recording layer lead-in area”) is an area where management information used for recording / reproduction of the recording layer 113 is recorded by a recording mark. Management information used for recording / reproduction of the recording layer 113 includes layer information such as a layer number assigned to which recording layer 113 is assigned, replacement management information regarding replacement processing of a defective area, OPC processing (calibration processing). The recording condition data such as the optimum laser power at the time of recording determined by (1) is included. Among these, at least the layer information is, for example, information recorded with a recording mark on each recording layer 113 before the multilayer optical disc 11 is actually used for data recording by the user. Such layer information may be recorded in advance on each recording layer when, for example, a multilayer optical disc is manufactured. If recording is performed when a multilayer optical disc is manufactured, layer information can be recorded for each manufacturing lot, so that layer information can be recorded more accurately without being subject to fluctuations in lot-to-lot variations.

[Disc transport mechanism 20]
The disk transport mechanism 20 takes out the target multilayer optical disk 11 from the disk cartridge 10 and loads it in the disk drive 31 in the drive unit 30, or conversely returns the multilayer optical disk 11 ejected from the disk drive 31 to the disk cartridge 10. Mechanism.

  The disk transport mechanism 20 operates independently so that, for example, a plurality of multilayer optical disks 11 can be taken out simultaneously or sequentially from the disk cartridge 10 and can be separately loaded into the plurality of disk drives 31 in the drive unit 30. A plurality of possible transport mechanisms may be provided.

[Drive unit 30]
A plurality of disk drives 31 are mounted on the drive unit 30. In the example of FIG. 5, five disk drives 31 are mounted. In the example of FIG. 5, five disk drives 31 are mounted. The number of multilayer optical disks 11 accommodated in the disk cartridge 10 and the number of disk drives 31 mounted in the drive unit 30 are not necessarily the same.

(Configuration of the disk drive 31)
6 and 7 are diagrams showing the configuration of a disk drive 31 that is an optical recording apparatus.
The disk drive 31 includes a first optical pickup 32 and a second optical pickup 32a. The first optical pickup 32 includes a recording / reproducing optical system corresponding to the recording / reproducing light and a guide optical system corresponding to the guide light. The second optical pickup 32a includes a reproducing optical system.

  The disk drive 31 includes a first PU corresponding circuit group 22 corresponding to the first optical pickup 32, a second PU corresponding circuit group 22a corresponding to the second optical pickup 32a, and a controller 83. The disk drive 31 includes a disk motor 91 that drives the multilayer optical disk 11.

  Further, the disk drive 31 includes a disk motor drive unit that controls the disk motor 91, a first feed mechanism that sends the first optical pickup 32 in the radial direction of the multilayer optical disk 11, and a second optical pickup 32a that is a multilayer optical disk. 11 includes a second feed mechanism for feeding in the radial direction. In FIG. 6 and FIG. 7, these illustrations are omitted.

  The controller 83 includes a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), and the like. The controller 83 controls the entire disk drive 31 based on a program loaded in the main memory area allocated to the RAM.

  As shown in FIG. 6, the recording / reproducing optical system of the first optical pickup 32 includes a first light source 33, a first collimator lens 34, a first polarization beam splitter 35, a first relay lens 36, and a second relay lens 36. The collimator lens 37, the combining prism 38, the quarter wavelength plate 39, the objective lens 60, the first light receiving lens 61, the first light receiving portion 62, and the like. Here, the combining prism 38, the quarter wavelength plate 39, and the objective lens 60 belong to both the recording / reproducing optical system and a guide optical system described later.

  The first light source 33 includes a laser diode that emits blue laser light as recording / reproducing light R1. The recording / reproducing light R 1 emitted from the first light source 33 is converted into parallel light by the first collimator lens 34, and passes through the first polarization beam splitter 35, the first relay lens 36 and the second collimator lens 37. The light enters the combining prism 38. The synthesizing prism 38 makes the optical axes of the recording / reproducing light R1 incident from the second collimator lens 37 and the guide light R2 incident from a third collimator lens belonging to a guide optical system, which will be described later, coincide with each other. And is incident on the objective lens 60 through the quarter-wave plate 39. The incident recording / reproducing light is collected by the objective lens 60 so as to be focused on the target recording layer 113 of the multilayer optical disc 11.

  The recording / reproducing light (returned light) reflected by the recording layer 113 is incident on the combining prism 38 via the objective lens 60 and the quarter wavelength plate 39, and is transmitted through the combining prism 38 in the incident direction. Return to the first polarization beam splitter 35 via the collimator lens 37 and the first relay lens 36. The first polarization beam splitter 35 reflects the return light of the first wavelength from the first relay lens 36 at an angle of about 90 degrees and passes through the first light receiving lens 61 to the first light receiving unit 62. Make it incident.

  For example, the first light receiving unit 62 includes a light receiving element whose light receiving surface is divided into four in the disk radial direction and the tangential direction, and outputs a voltage signal of a level corresponding to the light receiving intensity for each divided light receiving surface. To do.

  The guide optical system includes a second light source 63, a third collimator lens 64, a second polarizing beam splitter 65, a second relay lens 66, a fourth collimator lens 67, a combining prism 38, and a quarter wavelength plate 39. The objective lens 60, the second light receiving lens 68, the second light receiving portion 69, and the like.

  The second light source 63 emits guide light R2 that is red laser light. The guide light R2 emitted from the second light source 63 is converted into parallel light by the third collimator lens 64, and is combined through the second polarization beam splitter 65, the second relay lens 66, and the fourth collimator lens 67. The light enters the prism 38. As described above, the guide light R2 incident on the combining prism 38 is combined by the combining prism 38 so that the optical axis coincides with the recording / reproducing light R1 incident from the second collimator lens 37 of the recording / reproducing optical system. Then, the light enters the objective lens 60 through the quarter-wave plate 39. The incident guide light R <b> 2 is collected by the objective lens 60 so as to be focused on the guide layer 112 of the multilayer optical disk 11.

  The guide light R2 (return light) reflected by the guide layer 112 enters the synthesis prism 38 through the objective lens 60 and the quarter wavelength plate 39, and is reflected by the synthesis prism 38 at an angle of about 90 degrees. Returning to the second polarizing beam splitter 65 via the fourth collimator lens 67 and the second relay lens 66. The second polarization beam splitter 65 reflects the return light of the guide light R2 from the second relay lens 66 at an angle of about 90 degrees, and passes through the second light receiving lens 68 to the second light receiving unit 69. Make it incident.

  The second light receiving unit 69 is constituted by, for example, a light receiving element whose light receiving surface is divided into four in the disk radial direction and the tangential direction. The second light receiving unit 69 outputs a voltage signal corresponding to the amount of received light for each divided light receiving surface.

  The first optical pickup 32 is provided with a tracking actuator 70 and a focus actuator 79. The tracking actuator 70 moves the objective lens 60 in the disk radial direction that is perpendicular to the optical axis under the control of the tracking control unit 71. The focus actuator 79 moves the objective lens 60 in the optical axis direction under the control of the focus control unit 77.

  Further, the first optical pickup 32 has a first relay lens actuator 80 for moving the first relay lens 36 in the optical axis direction and a guide light in order to switch the recording layer 113 irradiated with the recording / reproducing light. In order to focus R2 on the guide layer 112, a second relay lens actuator 81 that moves the second relay lens 66 in the optical axis direction is provided.

Next, the configuration of the first PU corresponding circuit group 22 will be described.
As shown in FIG. 6, the first PU corresponding circuit group 22 includes a tracking error generation unit 82, a tracking control unit 71, a data modulation unit 72, a first light source driving unit 73, a second light source driving unit 74, and the like. , A data reproduction unit 76, a focus control unit 77, a first relay control unit 84, a second relay control unit 85, and a focus error generation unit 86.

  The data modulator 72 modulates the recording data supplied from the controller 83 and supplies the modulated signal to the first light source driver 73.

  The first light source drive unit 73 generates a drive pulse for driving the first light source 33 based on the modulation signal from the data modulation unit 72.

  The equalizer 75 performs an equalization process such as PRML (Partial Response Maximum Likelihood) on the reproduction RF signal from the first light receiving unit 62 to generate a binary signal.

  The data reproduction unit 76 demodulates data from the binary signal output from the equalizer 75, performs decoding processing such as error correction from the demodulated data, generates reproduction data, and supplies the reproduction data to the controller 83.

  The tracking error generation unit 82 generates a tracking error signal based on the output of the second light receiving unit 69 by, for example, a push-pull method, a differential push-pull method, a three-beam method, or the like.

  The tracking controller 71 performs tracking control by controlling the tracking actuator 70 based on the tracking error signal to move the objective lens 60 in a direction perpendicular to the optical axis. The tracking error generation unit 82 and the tracking control unit 71 correspond to a “first tracking processing unit” in the claims.

  The focus error generation unit 86 generates a focus error signal based on, for example, the astigmatism method based on the output of the first light receiving unit 62.

  The focus control unit 77 performs focus control by controlling the focus actuator 79 and moving the objective lens 60 in the optical axis direction based on the focus error signal.

  The first relay control unit 84 controls the first relay lens actuator 80 so as to switch the recording layer to be recorded and reproduced.

The second relay control unit 85 controls the second relay lens actuator 81 so that the guide light R2 is focused on the guide layer 112.
The above is the description of the first PU corresponding circuit group 22.

Next, the configuration of the second optical pickup 32a and the second PU corresponding circuit group 22a corresponding to the second optical pickup 32a will be described.
As shown in FIG. 7, the reproduction optical system of the second optical pickup 32a includes a third light source 33a, a fifth collimator lens 34a, a third polarization beam splitter 35a, a third relay lens 36a, and a sixth relay lens 36a. It comprises a collimator lens 37a, a quarter wavelength plate 39a, an objective lens 60a, a third light receiving lens 61a, a third light receiving portion 62a, and the like.

  The third light source 33a includes a laser diode that emits blue laser light as reproduction light R3. The reproduction light R3 emitted from the third light source 33a is converted into parallel light by the fifth collimator lens 34a, and the third polarization beam splitter 35a, the third relay lens 36a, and the sixth collimator lens 37a, 1/4. The light enters the objective lens 60a through the wave plate 39a. In the objective lens 60a, the incident reproduction light R3 is condensed so as to be focused on the target recording layer 113 of the multilayer optical disc 11.

  The reproduction light (return light) reflected by the recording layer 113 is transmitted to the third polarization beam splitter 35a via the objective lens 60a, the quarter wavelength plate 39a, the sixth collimator lens 37a, and the third relay lens 36a. Return. The third polarization beam splitter 35a reflects the return light of the first wavelength from the third relay lens 36a at an angle of about 90 degrees, and passes through the third light receiving lens 61a to the third light receiving unit 62a. Make it incident.

  The third light receiving unit 62a is composed of, for example, a light receiving element whose light receiving surface is divided into four in the disk radial direction and the tangential direction, and outputs a voltage signal of a level corresponding to the light receiving intensity for each divided light receiving surface. To do.

  The second optical pickup 32a is provided with a tracking actuator 70a and a focus actuator 79a. The tracking actuator 70a moves the objective lens 60a in the disk radial direction that is perpendicular to the optical axis under the control of the tracking control unit 71a. The focus actuator 79a moves the objective lens 60a in the optical axis direction under the control of the focus control unit 77a.

  Further, the second optical pickup 32a is provided with a third relay lens actuator 80a for moving the third relay lens 36a in the optical axis direction in order to switch the recording layer 113 irradiated with the recording / reproducing light. Yes.

Next, the configuration of the second PU corresponding circuit group 22a will be described.
The second PU corresponding circuit group 22a includes a tracking error generation unit 82a, a tracking control unit 71a, a third light source driving unit 73a, an equalizer 75a, a data reproduction unit 76a, a focus error generation unit 86a, a focus control unit 77a, A characteristic detector 78a and a third relay controller 84a are provided.

  The third light source drive unit 73a generates a drive current for emitting the reproduction light R3 from the third light source 33a, and supplies the drive current to the third light source 33a.

  The equalizer 75a performs an equalization process such as PRML (Partial Response Maximum Likelihood) on the reproduction RF signal from the third light receiving unit 62a to generate a binary signal.

  The data reproducing unit 76 a demodulates data from the binary signal output from the equalizer 75 a, performs decoding processing such as error correction from the demodulated data, generates reproduced data, and supplies the reproduced data to the controller 83.

  The tracking error generation unit 82a generates a tracking error signal by the push-pull method, the differential push-pull method, the 3-beam method, or the like based on the output of the third light receiving unit 62a.

  The tracking control unit 71a performs tracking control by controlling the tracking actuator 70a based on the tracking error signal and moving the objective lens 60a in a direction perpendicular to the optical axis. Here, the tracking error generator 82a and the tracking controller 71a correspond to a “second tracking processor” in the claims.

  The focus error generation unit 86a generates a focus error signal by, for example, the astigmatism method based on the output of the third light receiving unit 62a.

  The focus control unit 77a performs focus control by controlling the focus actuator 79a and moving the objective lens 60a in the optical axis direction based on the focus error signal.

  The third relay control unit 84a controls the third relay lens actuator 80a so as to switch the recording layer to be reproduced.

  The characteristic detection unit 78a receives the voltage signal output from the third light receiving unit 62a, detects the physical characteristic value of the reproduction light (return light) based on this voltage signal, and supplies it to the controller 83.

  A plurality of the disk drives 31 described above are mounted on the drive unit 30 and can be controlled independently, and information can be recorded and reproduced on the loaded multilayer optical disk 11 simultaneously.

[RAID controller 40]
A RAID (Redundant Arrays of Inexpensive Disks) controller 40, in response to a recording command from the host device 50, multiplexly records data on one or more disk drives 31 in the drive unit 30, or records them in a distributed manner by striping. RAID control is performed. The controller 83 of each disk drive 31 to which a recording or reproduction instruction is given from the RAID controller 40 performs control for recording or reproducing data on the multilayer optical disk 11.

[Host device 50]
The host device 50 is the highest-level device that controls the optical recording system 1. The host device 50 may be a personal computer. The host device 50 creates or prepares data for recording, and supplies a recording command for the data for recording to the RAID controller 40. Further, the host device 50 supplies a read command including a file name designated by a user or the like to the RAID controller 40, and acquires data of the corresponding file name from the RAID controller 40 as a response.

  As illustrated in FIG. 3, the host device 50 includes a CPU 51, a memory 52, a drive I / F 53, a disk transport mechanism I / F 54, and a system bus 56.

The CPU 51 performs arithmetic processing for executing a program stored in the memory 52 and controls exchange of information with each unit through the system bus 56.
The memory 52 is a main memory that stores programs to be executed by the CPU 51, operation results, and the like.

  The drive I / F 53 is an interface for communicating with the plurality of disk drives 31 through the RAID controller 40.

  The disk transport mechanism I / F 54 is an interface for communicating with the disk transport mechanism 20.

[Verify operation]
Next, a verify operation in the disk drive 31 according to the present embodiment will be described.

FIG. 8 is a diagram for explaining a verification mechanism in the disk drive 31 according to the present embodiment.
The disk drive 31 has a first optical pickup 32 and a second optical pickup 32a. For example, the first optical pickup 32 and the second optical pickup 32a may be independent so that they can be moved individually in the disk radial direction, or can be moved simultaneously. It may be integrated. 6, 7, and 8, it is assumed that the first optical pickup 32 and the second optical pickup 32 a are independent from each other. In this case, the controller 83 can move the first optical pickup 32 and the second optical pickup 32a in the disk radial direction by controlling the corresponding feed mechanisms (not shown).

The second optical pickup 32a is spirally formed on the guide layer 112, for example, with respect to the recording position so that the recorded data can be reproduced during recording of the data by the first optical pickup 32. It is positioned on the downstream side in the recording direction X along the provided guide track 121. Here, the downstream side in the recording direction X along the guide track 121 is:
1. 1. Downstream side in the disk circumference 2. Downstream side in the disk radial direction The meaning of the downstream side between the recording layers of a multilayer optical disk is included.

Next, the verify operation by the disk drive 31 according to the present embodiment will be described with reference to FIG.
A data recording command is given from the host device 50 to the controller 83 of one or more disk drives 31 in the drive unit 30 through the RAID controller 40. Since the operation of each disk drive 31 when receiving a recording command is the same, the operation of one disk drive 31 will be described.

  The controller 83 of the disk drive 31 controls the first feed mechanism so as to move the first optical pickup 32 to the disk radial position corresponding to the unrecorded area in the multilayer optical disk 11, and controls a disk motor drive unit (not shown). The multi-layer optical disk 11 is driven to rotate at an appropriate speed by control.

  The controller 83 controls the first relay lens of the first optical pickup 32 so that the recording light from the objective lens 60 of the first optical pickup 32 is focused on the target recording layer 113 (L0) of the multilayer optical disc 11. A control command is supplied to the focus control unit 77 so as to control the position of the optical axis direction 36 and start pulling in the focus servo.

  The controller 83 also has an optical axis of the second relay lens 66 of the first optical pickup 32 so that the guide light from the objective lens 60 of the first optical pickup 32 is focused on the guide layer 112 of the multilayer optical disc 11. A control command is supplied to the tracking control unit 71 so as to control the position in the direction and start the tracking servo pull-in.

  The controller 83 of the disk drive 31 stores the recording data 201 transferred from the host device 50 through the RAID controller 40 in the memory 52 and transfers the recording data 201 from the memory 52 to the data modulation unit 72. The data modulator 72 generates a recording signal by modulating the recording data 201 and adding an error correction code, and supplies the recording signal to the first light source driving unit 73. The first light source driving unit 73 generates a driving pulse for the first light source 33 based on the recording signal and supplies it to the first light source 33. Thereby, recording of data on the recording layer 113 by the recording light from the first optical pickup 32 is started. That is, data recording to the target recording layer 113 of the multilayer optical disc 11 is started.

  When the recording of data by the first optical pickup 32 is completed by a predetermined amount, for example, a predetermined data amount, a predetermined time, a predetermined radial distance, etc., the controller 83 moves the second optical pickup 32a in the multilayer optical disc 11. The second feed mechanism is controlled to move to the disk radial position where the current recording is started.

  The controller 83 causes the third relay lens of the second optical pickup 32a to focus the reproduction light from the objective lens 60a of the second optical pickup 32a on the target recording layer 113 (L0) of the multilayer optical disc 11. A control command is supplied to the focus control unit 77 so as to control the position of the optical axis direction 36a and start pulling in the focus servo. Further, the controller 83 supplies a control command to the tracking control unit 71a so as to start the tracking servo pull-in by DPD with respect to the recording mark of the target recording layer 113 (L0) of the multilayer optical disc 11.

  Next, the controller 83 supplies a control command to the third light source driving unit 73a so that the reproduction light is emitted from the third light source 33a. Thereby, the reproduction of the data recorded by the first optical pickup 32 is started. The data 202 reproduced by the data reproducing unit 76 a is supplied to the controller 83 and stored in the memory 52.

  The CPU 51 of the controller 83 executes the verify 203 by collating the reproduction data 202 stored in the memory 52 with the recording data 201, for example. The verify 203 is executed each time reproduction data 202 in a unit that can be verified is obtained from the multilayer optical disc 11. When an error such as a collation mismatch is detected in the verify process, the CPU 51 records the data unit in which the error is detected in another area by a replacement process.

  Further, the CPU 51 of the controller 83, for example, performs OPC based on a signal read from the recorded area by the second optical pickup 32a even during data recording using the first optical pickup 32. (Optimized Power Control) 204 can be executed.

  That is, the characteristic detection unit 78a receives the voltage signal output from the third light receiving unit 62a, detects the physical characteristic value of the return light based on this voltage signal, and supplies the characteristic value data 209 to the controller 83. To do. As the physical characteristic value of the return light, for example, an asymmetry value which is an evaluation index indicating the symmetry of amplitude between the shortest recording mark and the shortest space and the longest recording mark and the longest space in the reproduction RF signal, and similarly the symmetry of the RF signal However, the present invention is not limited to these values.

  The CPU 51 of the controller 83 corrects the intensity level (power level) of the recording laser beam emitted from the first light source 33 of the first optical pickup 32 based on the characteristic value detected by the characteristic detector 78a. The predetermined OPC 204 is executed, for example, by supplying a control signal for correction to the first light source driving unit 73.

[Effects of this embodiment]
As described above, the disk drive 31 according to the present embodiment is configured so that the recorded data can be reproduced by the second optical pickup 32a during recording by the first optical pickup 32. As a result, the recording data can be verified in parallel with the recording of the data on the multilayer optical disk 11. As a result, the time from the start of recording to the end of verification can be greatly shortened. In particular, when recording a large amount of data, a remarkable speed increase is achieved.

  Furthermore, according to the present embodiment, when the data recorded on the multilayer optical disc 11 is reproduced by the second optical pickup 32a, the track mark is performed on the recording mark of the recording layer. Compared to the case where tracking is performed on the guide track 121, for example, tracking error due to tilt can be reduced, so that tracking can be performed with high accuracy and the frequency of retries during playback can be suppressed. Can also shorten the time from the start of recording to the end of verification.

<Modification 1>
FIG. 9 is a diagram illustrating a first modification of the present embodiment.
When data is reproduced from the multilayer optical disk 11 and transferred to the host device 50, the controller 83 may control to use the first optical pickup 32 and the second optical pickup 32a for reproduction. That is, the controller 83 controls the first optical pickup 32 and the second optical pickup 32a to simultaneously read data at different addresses on the multilayer optical disc 11, and combines the two reproduction data 205 and 202 in the memory 52 ( 206) and transfer to the host device 50. Thereby, the transfer rate at the time of reproduction | regeneration can be raised significantly.

<Modification 2>
FIG. 10 is a diagram illustrating a second modification of the present embodiment.
In the recording operation including the verification, the controller 83 can correct the tilt caused by the warp of the multilayer optical disc 11 in real time using the output of the third light receiving unit 62a of the second optical pickup 32a. It is. In order to perform the tilt correction, the first optical pickup 32 and the second optical pickup 32a are provided with a tilt actuator or the like for adjusting the inclinations of the objective lenses 60 and 60a in the radial direction and the tangential direction, respectively.

  The CPU 51 of the controller 83 detects the tilt amount using the output data 207 of the third light receiving unit 62a, generates a correction value so that the tilt amount becomes zero, and outputs a control signal to the tilt actuator. Thus, for example, even when data is being recorded on the multilayer optical disc 11, the tilt correction 208 of the first optical pickup 32 and the second optical pickup 32a can be performed.

As a specific method of correcting the tilt using the output of the third light receiving unit 62a of the second optical pickup 32a, a method using the modulation degree of the amplitude voltage of the sum signal (reproduced RF signal) of each voltage signal, etc. There is.
The modulation degree of the amplitude voltage of the reproduction RF signal is such that the peak voltage of the reproduction RF signal is RFtop and the bottom value is RFbottom.
(RFtop−RFbottom) / RFtop
It is represented by
The controller 83 performs tilt correction so that the modulation degree of the amplitude voltage of the reproduction RF signal is maximized.

  Note that the tilt correction based on the modulation degree of the amplitude voltage of the reproduction RF signal is merely an example, and other known methods may be used to perform the tilt correction.

The present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the gist of the present invention.
For example, as another embodiment of the present invention, only one disk drive 31 may be used, and in this case, a cartridge and a disk transport mechanism are not required, and thus the size can be reduced.

DESCRIPTION OF SYMBOLS 1 ... Optical recording system 11 ... Multi-layer optical disk 31 ... Disk drive 32 ... 1st optical pickup 32a ... 2nd optical pickup 50 ... Host apparatus 51 ... CPU
52 ... Memory 71, 71a ... Tracking controller 87, 82a ... Tracking error generator 78a ... Characteristic detector 112 ... Guide layer 113 ... Recording layer 201 ... Recorded data 202, 205 ... Playback data 203 ... Verify 204 ... OPC
206: Coupling 208 ... Tilt correction 207 ... Light receiving unit output data 209 ... Characteristic value data

Claims (6)

An optical recording apparatus for recording on an optical disc having one or more recording layers capable of recording information and a guide layer provided with a guide track for tracking,
A first optical pickup capable of recording data on the recording layer of the optical disc;
A second optical pickup capable of reading the recorded data from the optical disc;
An optical recording apparatus comprising: a control unit that performs control such that during recording of the data using the first optical pickup, the recorded data is read using the second optical pickup and verified. The optical recording apparatus according to claim 1,
The first optical pickup includes a recording optical system for performing recording by irradiating the recording layer of the optical disc with a recording laser beam, and irradiating the guide layer of the optical disc with a guide laser beam. A guide optical system that outputs a first signal corresponding to the return light,
The second optical pickup includes a first reproducing optical system that irradiates the recording layer of the optical disc with a reproducing laser beam and outputs a second signal corresponding to the return light,
The optical recording apparatus further includes:
A first tracking processing unit that performs processing related to tracking of the first optical pickup using the first signal output from the guide optical system of the first optical pickup;
A second tracking processing unit that performs processing related to tracking of the second optical pickup using the second signal output from the first reproducing optical system of the second optical pickup. Recording device. The optical recording apparatus according to claim 2,
Based on the second signal output from the reproduction optical system of the second optical pickup, further comprising a characteristic detection unit for detecting a physical characteristic value of the return light;
The control unit is an optical recording apparatus that performs OPC (Optimized Power Control) based on the detected physical characteristic value. The optical recording apparatus according to claim 1, wherein:
The first optical pickup includes a second reproduction optical system that irradiates the recording layer of the optical disc with a laser beam for reproduction and outputs a third signal corresponding to the return light,
The control unit controls to perform reproduction by simultaneously using the second reproduction optical system of the first optical pickup and the first reproduction optical system of the second optical pickup. The optical recording apparatus according to claim 1, wherein:
The controller performs tilt correction of the first optical pickup and the previous second optical pickup based on the second signal output from the first reproduction optical system of the second optical pickup. Optical recording device. A method of recording on an optical disc having one or more recording layers capable of recording information and a guide layer provided with a guide track for tracking,
Data is recorded on the recording layer of the optical disc by a first optical pickup, and the recorded data is reproduced during recording by an optical pickup operable independently of the first optical pickup. An optical recording method for performing verification.

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