JP2008108400A - Disk drive apparatus and disk recording capacity discrimination method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enable rapid discrimination of a recording capacity of a disk without relying on management information read-out. <P>SOLUTION: A head section (pickup) is put into a state of performing information read-out in a specific radial position with respect to a loaded disk and the disk is rotated at a specific speed. The frequency of a read-out wobble signal is measured and the recording capacity of the disk is discriminated. If reproduction is performed in the specific radial position at a specific rotating speed, the measured wobble frequency varies due to the difference in the density complying with the disk capacity and therefore, the capacity discrimination is made possible by the wobble signal frequency. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a disk drive device for recording or reproducing information on a disk recording medium on which a wobbling groove is formed, and a disk recording capacity determination method thereof.

JP 2000-322742 A JP 2006-179138 A

  Patent Documents 1 and 2 disclose a technique for determining the type of an optical disc by measuring the wobble period of the optical disc on which a wobbling groove is formed.

As a technique for recording / reproducing digital data, optical discs (including magneto-optical discs) such as CD (Compact Disc), Mini Disc (Mini-Disc), and DVD (Digital Versatile Disc) are used as recording media. There is data recording technology.
For example, CD-type discs include CD-DA (Compact Disc-Digital Audio), CD-ROM (Compact Disc-Read Only Memory), CD-R (Compact Disc-Recordable), and CD-RW (Compact Disc-Rewritable). Etc. are known.
In addition, DVD-type discs include DVD-ROM (Digital Versatile Disc-Read Only Memory), DVD-R (Digital Versatile Disc-Recordable), DVD-RW (Digital Versatile Disc-Rewritable), DVD + R, DVD + RW, DVD-RAM. (Digital Versatile Disc-Random Access Memory) is known.

These optical disks include, for example, CD-DA, CD-ROM, DVD-ROM and other reproduction-only types, CD-R, CD-RW, DVD-R, DVD-RW, DVD + R, DVD + RW, DVD- There is a type that can record user data such as RAM. In the recordable type, data can be recorded by using a magneto-optical recording method, a phase change recording method, a dye film change recording method, or the like. The dye film change recording method is also called a write-once recording method, and can be recorded only once and cannot be rewritten. On the other hand, the magneto-optical recording method and the phase change recording method can rewrite data, and are used for various purposes including recording of various content data such as music, video, games, application programs and the like.
Furthermore, in recent years, a high-density optical disk called a Blu-ray Disc (registered trademark) has been developed, and the capacity has been significantly increased.

  A read-only management information area called PIC (Permanent Information & Control data), for example, is secured on the inner circumference side of the optical disk described above, as in the disk 90 shown in FIG. In the PIC area, various information such as physical information of the disk is stored in advance, and information corresponding to the recording capacity of the disk is also stored.

For example, FIG. 8 shows a part of the configuration of the disk drive device. The operation of reading the PIC by the disk drive device is as follows.
When the system controller 10 gives an instruction to read the PIC to the servo system 38, the servo system 38 executes thread transfer and focus / tracking servo control of the optical pickup 1, and the optical pickup 1 performs data in the PIC area. A state in which reading can be executed.
Further, the system controller 10 controls the spindle driver 17 to cause the spindle motor 2 to execute a CLV (Constant Linear Velocity) rotation operation so as to obtain a predetermined linear velocity for reading at a radial position as the PIC area.
The optical pickup 1 irradiates the PIC area of the disk 90 with a laser and detects the reflected light. The information signal obtained from the reflected light is supplied to the reproduction system 39, and the information recorded on the PIC is decoded in the reproduction system 39 and supplied to the system controller 10.
For example, when the disk 90 is loaded, the disk drive device reads the PIC information in this manner, thereby acquiring the disk type, recording capacity, various other physical information, and management information.

Incidentally, the linear velocity at the time of disc recording / reproduction is determined according to the type (format) of the disc. For example, in the same type of disc, when there are discs with different recording capacities, the recording density is different. Therefore, it is necessary to change the spindle rotation speed in accordance with the recording capacity.
The “recording capacity” in this specification refers to a recording capacity per one recording layer of the disc. For example, in Blu-ray Disc, not only a disc having one recording layer, but also a two-layer disc having two recording layers and a disc having more than one recording layer have been developed. It refers to the recording capacity per layer.

  The need to change the spindle rotation speed in accordance with the recording capacity means that when reading PIC, the rotation speed of the spindle motor is such that a predetermined linear velocity can be obtained according to the recording capacity of the disk. Means that must be decided. That is, before reading the PIC and grasping the recording capacity of the disk, the disk drive device determines the recording capacity of the disk, and the PIC cannot be read unless the rotation speed of the spindle motor is set according to the recording capacity. become.

However, this has not been a problem in the past due to the following circumstances.
That is, in a certain type of optical disc, if there is only one type of recording capacity, the rotational speed of the spindle motor and the center frequency of the reproduction signal processing PLL (PLL for reproduction clock generation) are set when the disc is loaded. I was able to decide uniquely. Of course, in this case, it is not necessary to control the rotation speed of the spindle motor in accordance with the recording capacity, and for this reason, the information on the recording capacity of the disk stored in the PIC is rarely used (utilization). Did not have to).

Considering a CD type optical disc, there are a plurality of types of disc recording capacities (640 MB (Mega Byte), 700 MB, etc.). In CD, the difference in recording capacities is about 10%. There was no problem even if the linear velocity deviated from the predetermined velocity.
As is well known, for a signal (reproduced RF signal) read from the disk, a reproduction clock synchronized with the signal is generated by PLL processing, and the reproduction signal is processed based on the reproduction clock. In other words, if the linear velocity is within a range in which a recovered clock can be generated by the PLL circuit, the recovery process can be executed without any problem.
In the case of CD, the difference in linear velocity according to the recording capacity is such that it falls within the capture range of the PLL circuit. Therefore, for example, when the spindle motor is rotated so that a predetermined linear velocity can be obtained with a 640 MB disk, a reproduction clock synchronized with the reproduction RF signal can be generated even if a 700 MB disk is loaded.

For example, consider the case where the spindle motor speed setting and the center frequency setting of the PLL circuit for generating a reproduction clock are set for a 640 MB disk, and a 700 MB disk PIC is read at a linear speed for the 640 MB disk.
FIG. 9A shows the capture range of the PLL circuit from the PLL allowable minimum frequency to the PLL allowable maximum frequency. The PLL center frequency is set in accordance with the case where information on a 640 MB disc is read at the linear speed for the 640 MB disc.
Here, even if a 700 MB disc is loaded, the reproduction RF signal from, for example, the PIC of the 700 MB disc falls within the range of the PLL allowable minimum frequency and the PLL allowable maximum frequency as shown in the figure. Therefore, a reproduction clock synchronized with the reproduction RF signal can be generated, and PIC information can be correctly decoded.
In this case, since the disc can be discriminated from the PIC information as a 700 MB disc, the linear velocity error and PLL center frequency setting can be corrected according to the recording capacity discrimination result.

  Conversely, when the spindle motor speed setting and the center frequency setting of the PLL circuit for generating the reproduction clock are set for 700 MB disk and the PIC of the 640 MB disk is read at the linear speed for 700 MB disk, the reproduction RF The frequency of the signal falls within the range of the PLL allowable minimum frequency and the PLL allowable maximum frequency, and PIC information can be decoded. Of course, in this case as well, the spindle rotational speed and the PLL center frequency setting may be corrected according to the determination result of the recording capacity.

  For this reason, conventionally, there is no problem even if the spindle rotational speed is not set so as to obtain a predetermined linear velocity corresponding to the recording capacity of the disc.

  However, as the capacity of the optical disk medium has increased, the above-mentioned point has occurred as a problem. For example, in a high-density optical disc such as a Blu-ray disc, there are a plurality of types having a plurality of recording capacities, but the difference between the recording capacities of the discs having the minimum recording capacities and the discs having the maximum recording capacities becomes considerably large. .

When the difference in recording capacity between the minimum recording capacity disk and the maximum recording capacity disk becomes larger than a certain level, a situation in which the PIC cannot be read occurs.
For example, it is assumed that the maximum recording capacity disk is loaded into the disk drive device and the PIC of this disk is read while the speed setting of the spindle motor and the PLL center frequency setting are set for the minimum recording capacity disk.
In that case, as shown in FIG. 9B, the RF signal frequency at the time of PIC reproduction exceeds the maximum allowable PLL frequency. Therefore, the reproduction clock cannot be properly generated, and the PIC information cannot be accurately decoded. As a result, after reading the recording capacity information of the disk stored in the PIC, the spindle rotational speed and the PLL center frequency setting cannot be reset to an appropriate value.

Conversely, when the PIC of the minimum recording capacity disk is read with the spindle motor speed setting and PLL center frequency setting set for the maximum recording capacity disk, as shown in FIG. The RF signal frequency during PIC playback falls below the PLL allowable minimum frequency.
Also in this case, PIC information cannot be read, and the spindle rotation speed and PLL center frequency setting cannot be reset.

  As shown in the above example, depending on the type of disc, the difference between the minimum and maximum recording capacities as the disc recording capacity type is larger than a certain level. In this case, information can be read with different capacity type settings. Therefore, the disc recording capacity cannot be determined based on the PIC information and appropriate settings cannot be made.

As a method for solving this problem, the performance of the PLL circuit for generating the recovered clock is greatly improved, and the range of the PLL allowable minimum frequency and the PLL allowable maximum frequency as the capture range is widened, so that the disk recording capacity is increased. It is conceivable that the PIC of each type of disk can be read even if the difference between the two is large.
However, this requires redesigning the reproduction signal processing LSI including the PLL circuit, which entails enormous costs and time.
Also, if there are disk drive devices already on the market, all of the disk drive devices must be collected and the reproduction signal processing system LSI must be replaced, which also requires enormous costs and time. It is not a realistic method.

As another method, it is considered that the spindle speed and the PLL center frequency are changed in a combination as long as possible until the PIC can read the disk loaded in the disk drive device. It is done. That is, if there are x types of recording capacity types, the setting of the x types is sequentially performed to try to read the PIC.
However, in this case, of course, there is a high possibility that the time until the completion of reading the PIC will be long, and it will be a user-unfriendly device for the user, which is not an appropriate method.

  Therefore, the present invention provides a method for discriminating the recording capacity of a disk in a short time without depending on the recording capacity information stored in the PIC, even in the case of a type of disk in which the difference between the minimum recording capacity and the maximum recording capacity is large. The purpose is to do.

A disk drive device according to the present invention includes a head unit that reads information from a disk recording medium on which a wobbling groove is formed, a rotation driving unit that rotates the disk recording medium at a constant linear velocity, The wobble frequency measuring unit that measures the frequency of the wobble signal read to the head unit as wobbling groove information, and the head unit is in a state of reading information at a specific radial position with respect to the loaded disk recording medium. And a control unit for determining the recording capacity of the loaded disk recording medium based on the frequency detected by the wobble frequency measurement unit at the time when the rotation driving unit is rotated at a specific speed. .
In addition, the wobble frequency measurement unit is a frequency pulling unit that pulls in the oscillation frequency with respect to the average frequency of the wobble signal read by the head unit, and the frequency pulling unit performs the frequency pulling in, A phase pull-in unit that pulls in a phase of the oscillation frequency with respect to the wobble signal, and detects an input voltage value of the voltage controlled oscillator in the phase pull-in unit as a value corresponding to the wobble frequency.
The control unit sets a threshold for the frequency of the wobble signal measured by the wobble frequency measurement unit, and loads the frequency measured by the wobble frequency measurement unit based on a result of comparison with the threshold. The recording capacity of the disc recording medium is discriminated.

  The disc recording capacity discriminating method of the present invention reads information from a disc recording medium as a disc recording capacity discriminating method of a disc drive apparatus for recording or reproducing information on a disc recording medium in which a wobbling groove is formed. A step of causing the head unit to read information from the loaded disk recording medium at a specific radial position; a step of rotating the loaded disk recording medium at a specific speed by a rotation driving unit; As the wobbling groove information of the loaded disk recording medium, the step of measuring the frequency of the wobble signal read by the head unit, and based on the measured frequency of the wobble signal, the loaded disk recording medium Determining the recording capacity.

According to the present invention, when there are a plurality of recording capacity types on a certain type of disc, the recording capacity can be determined by measuring the wobble frequency.
For example, assume that there are three types of recording capacities A, B, and C. When a disk having a recording capacity A is loaded, a rotational speed for obtaining a predetermined linear velocity (for example, a linear velocity defined in the disk format) at a specific radius position r is defined as VA. Further, when a disk having a recording capacity A is loaded, it is assumed that the wobble frequency observed when reading information at a specific radius position r with the spindle rotation speed as VA is F.
Then, when the disk is loaded and reproduction at the radial position r is performed at the rotational speed VA, if the wobble frequency is F, the disk can be identified as a disk having the recording capacity A. On the other hand, discs with recording capacities B and C have different recording densities and wobble periods, so that wobble frequencies other than F are observed when reproduction is performed in the same situation. That is, the wobble frequency observed depending on the recording density is a predetermined value other than F.
In other words, by performing reproduction at a specific radial position at a specific rotational speed, a value corresponding to the recording capacity of the disc is detected as a measured value of the wobble frequency.

According to the present invention, by performing reproduction at a specific radial position and at a specific rotation speed, a value corresponding to the recording capacity of the disk is detected as a measured value of the wobble frequency, and the recording of the loaded disk is thereby performed. The capacity can be determined. In other words, the recording capacity of the disc can be determined without relying on management information such as PIC, and the setting (rotation setting or PLL center frequency setting) according to the recording capacity can be made based on the determination result. Even if is loaded, it can be properly reproduced.
Further, since the present invention can be realized only by adding microcomputer software as a control unit without adding new hardware, there is no cost increase due to an increase in parts.
Further, the frequency measurement of the wobble signal is performed at high speed by dedicated hardware as a wobble frequency measurement unit, so that the discrimination operation can be performed quickly and the performance of the disk drive device is also improved.

  Embodiments of a disk drive device and a disk recording capacity determination method according to the present invention will be described below. Here, an example of a disk drive device corresponding to a high-density disk such as a Blu-ray disk will be given.

FIG. 1 is a block diagram of a disk drive device according to the present embodiment that can perform recording and reproduction corresponding to an optical disk 90.
The disc 90 is, for example, a recordable disc of the above-described Blu-ray disc system. In the case of a recordable disc, a groove (groove) is formed on the disc by meandering (wobbling), and this wobbling groove is used as a recording / reproducing track. Groove wobbling includes so-called ADIP (Address in Pregroove) data. In other words, the address on the disk can be obtained by detecting the wobbling information of the groove.
In the case of a recordable disc, recording marks are recorded as phase change marks and dye change marks on tracks formed by wobbling grooves. These marks are recorded in RLL (1, 7) PP modulation system (RLL; Run Length Limited, PP: Parity preserve / Prohibit rmtr (repeated minimum transition run length)) and the like.

When the disk 90 is loaded into the disk drive device, it is loaded on a turntable (not shown), and is rotationally driven by the spindle motor 2 at a constant linear velocity (CLV) during recording / reproducing operations.
During reproduction, the mark information recorded on the track on the disk 90 is read out by the optical pickup (optical head) 1.
When the disk 90 is a recordable disk, the user data is recorded as a phase change mark or a dye change mark on the track on the disk 90 by the optical pickup 1 at the time of data recording.
In addition, an area as a PIC is prepared on the inner peripheral side of the disk 90, and reproduction-only management information and physical information of the disk are recorded by embossed pits or wobbling grooves. Is done.
Further, the ADIP information embedded as wobbling of the groove track on the disk 90 is also read from the recordable disk 90 by the optical pickup 1.

In the optical pickup 1, a laser diode serving as a laser light source, a photodetector for detecting reflected light, an objective lens serving as an output end of the laser light, a laser beam is irradiated onto the disk recording surface via the objective lens, and An optical system or the like for guiding the reflected light to the photodetector is formed. The laser diode outputs, for example, a so-called blue laser having a wavelength of 405 nm. The NA by the optical system is 0.85.
In the optical pickup 1, the objective lens is held so as to be movable in the tracking direction and the focus direction by a biaxial mechanism.
The entire optical pickup 1 can be moved in the radial direction of the disk by a thread mechanism 3.
The laser diode in the optical pickup 1 is driven to emit laser light by a drive signal (drive current) from the laser driver 13.

Reflected light information from the disk 90 is detected by a photo detector, converted into an electrical signal corresponding to the amount of received light, and supplied to the matrix circuit 4.
The matrix circuit 4 includes a current-voltage conversion circuit, a matrix calculation / amplification circuit, and the like corresponding to output currents from a plurality of light receiving elements as photodetectors, and generates necessary signals by matrix calculation processing.
For example, a reproduction RF signal corresponding to reproduction data, a focus error signal for servo control, a tracking error signal, and the like are generated.
Further, a push-pull signal is generated as a signal related to groove wobbling, that is, a signal for detecting wobbling.
The reproduction RF signal output from the matrix circuit 4 is supplied to the reproduction processing system 5, the focus error signal and tracking error signal are supplied to the optical block servo circuit 11, and the push-pull signal is supplied to the wobble processing system 6.

The reproduction processing system 5 includes an A / D conversion unit 20, a Viterbi decoding unit 21, a reproduction processing unit 22, and a PLL unit 23.
The A / D converter 20 converts the reproduction RF signal, which is an analog signal, into digital data. The output of the A / D conversion unit 20 is supplied to the subsequent Viterbi decoding unit 21 and also to the PLL unit 23, and a reproduction clock CKd used for the reproduction process is generated by the phase locked loop. The generated clock CKd is used as a sampling clock for the A / D conversion unit 20 and used for decoding processing in the Viterbi decoding unit 21.

The reproduced RF signal read from the disk 90 and digitized is subjected to binarization decoding processing by the Viterbi decoding unit 21. For example, the Viterbi decoding unit 21 performs PR (Partial Response) equalization processing and Viterbi decoding (maximum likelihood decoding) processing, and binary data by partial response maximum likelihood decoding processing (PRML detection method: Partial Response Maximum Likelihood detection method). Get a column.
The obtained binary data string is subjected to decoding processing, error correction processing, and the like in the reproduction processing unit 22, and the reproduction data is demodulated. In other words, the reproduction processing unit 22 performs demodulation processing, deinterleaving, ECC decoding processing for performing error correction, and the like on the data recorded on the disk 90 that has been subjected to RLL (1, 7) PP modulation, and the like. The reproduction data Dp from is demodulated.

  The reproduction data demodulated by the reproduction processing unit 22 is transferred to the host interface 8 and transferred to the host device 100 based on an instruction from the system controller 10. The host device 100 is, for example, a computer device or an AV (Audio-Visual) system device.

If the disc 90 is a recordable disc, ADIP information processing is performed during recording / reproduction.
That is, a push-pull signal (wobble signal) output from the matrix circuit 4 as a signal related to groove wobbling is supplied to the wobble processing system 6.
The wobble processing system 6 is provided with an A / D converter 24, an MSK / STW demodulator 25, a wobble data decoder 26, and a PLL unit 27.
The push-pull signal (wobble signal) is converted into digital data by the A / D converter 24, and then MSK demodulation and STW demodulation are performed by the MSK / STW demodulator 25 to demodulate a data string that constitutes an ADIP address and the like. . This data string is decoded by the wobble data decoder 26, and ADIP information such as an address value is demodulated. The demodulated ADIP information is supplied to the system controller 10.
The PLL unit 27 generates a wobble clock CKw that is synchronized with the push-pull signal (wobble signal). The wobble clock CKw is processed by the A / D converter 24, the MSK / STW demodulator 25, and the wobble data decoder 26. Used as a clock.
As will be described later with reference to FIG. 2, the PLL unit 27 is provided with a configuration in which the system controller 10 can detect the wobble frequency.

During recording, recording data is transferred from the host device 100, and the recording data is supplied to the recording processing unit 7 via the host interface 8.
The recording processing unit 7 performs error correction code addition (ECC encoding), interleaving, subcode addition, and the like as recording data encoding processing. Further, RLL (1-7) PP modulation is performed on the data subjected to these processes.

The recording data processed by the recording processing unit 7 is subjected to a recording compensation process in the write strategy unit 14 for fine adjustment of optimum recording power and laser drive pulse waveform for recording layer characteristics, laser beam spot shape, recording linear velocity, etc. The laser drive pulse signal in a state where the adjustment is performed is supplied to the laser driver 13. The laser driving pulse signal waveform is adjusted based on an instruction from the system controller 10.
Then, the laser driver 13 supplies the laser driving pulse signal subjected to the recording compensation process to the laser diode in the optical pickup 1 to execute the laser emission driving. As a result, a mark corresponding to the recording data is formed on the disk 90.
The laser driver 13 includes a so-called APC circuit (Auto Power Control), and the laser output depends on the temperature or the like while monitoring the laser output power by the output of the laser power monitoring detector provided in the optical pickup 1. Control to be constant. The target value of the laser output at the time of recording and reproduction is given from the system controller 10, and the laser output level is controlled to be the target value at the time of recording and reproduction.

The optical block servo circuit 11 generates various servo drive signals for focus, tracking, and thread from the focus error signal and tracking error signal from the matrix circuit 4 and executes the servo operation.
That is, a focus drive signal and a tracking drive signal are generated according to the focus error signal and the tracking error signal, and the biaxial driver 18 drives the focus coil and tracking coil of the biaxial mechanism in the optical pickup 1. Thus, a tracking servo loop and a focus servo loop are formed by the optical pickup 1, the matrix circuit 4, the optical block servo circuit 11, the biaxial driver 18, and the biaxial mechanism.
The optical block servo circuit 11 turns off the tracking servo loop in response to a track jump command from the system controller 10 and outputs a jump drive signal to execute a track jump operation.
The optical block servo circuit 11 generates a thread drive signal based on a thread error signal obtained as a low frequency component of the tracking error signal, access execution control from the system controller 10, and the like. To drive. Although not shown, the sled mechanism 3 has a mechanism including a main shaft that holds the optical pickup 1, a sled motor, a transmission gear, and the like. The sled mechanism 3 drives the sled motor according to a sled drive signal. The slide movement is performed.

The spindle servo circuit 12 performs control to rotate the spindle motor 2 at CLV.
The spindle servo circuit 12 obtains the wobble clock CKw generated by the PLL processing for the wobble signal in the PLL unit 27 as the current rotational speed information of the spindle motor 2, and compares it with predetermined CLV reference speed information. Generate a spindle error signal.
Further, at the time of data reproduction, the reproduction clock CKd generated by the PLL unit 23 becomes the current rotation speed information of the spindle motor 2, so a spindle error signal is generated by comparing this with predetermined CLV reference speed information. You can also
The spindle servo circuit 12 outputs a spindle drive signal generated according to the spindle error signal, and causes the spindle driver 17 to execute CLV rotation of the spindle motor 2.
Further, the spindle servo circuit 12 generates a spindle drive signal in response to a spindle kick / brake control signal from the system controller 10, and also executes operations such as starting, stopping, acceleration, and deceleration of the spindle motor 2.

Various operations of the servo system and the recording / reproducing system as described above are controlled by a system controller 10 formed by a microcomputer.
The system controller 10 executes various processes in accordance with commands from the host device 100 given through the host interface 8.
For example, when a write command (write command) is issued from the host device 100, the system controller 10 first moves the optical pickup 1 to an address to be written. Then, the recording processing unit 7 causes the encoding process to be executed as described above for data transferred from the host device 100 (for example, video data, audio data, etc.). Recording is executed by the laser driver 13 driving to emit laser light in accordance with the encoded data as described above.

Further, for example, when a read command for requesting transfer of certain data recorded on the disk 90 is supplied from the host device 100, the system controller 10 first performs seek operation control for the instructed address. That is, a command is issued to the optical block servo circuit 11, and the access operation of the optical pickup 1 targeting the address specified by the seek command is executed.
Thereafter, operation control necessary for transferring the data in the designated data section to the host device 100 is performed. That is, data is read from the disk 90, the reproduction processing in the reproduction processing system 5 is executed, and the requested data is transferred.

  The memory unit 9 stores program codes executed in the system controller 10 (microcomputer), is used for temporarily storing work data being executed, various management information read from the disk 90, physical information, etc. In this figure, the memory unit 9 is shown as including both a volatile memory and a non-volatile memory. For example, ROM (Read Only Memory) for storing programs, RAM (Random Access Memory) for temporary storage of calculation work areas and various information, and nonvolatile memories such as EEPROM-Electrically Erasable and Programmable Read Only Memory (ROM) .

Further, as the sensor 15, a sensor for detecting the position of the optical pickup 1 (radial position with respect to the disk 90 due to sled movement) is provided.
FIG. 3 schematically shows a state in which the disk 90 is mounted on the spindle motor 2. As shown in FIG. 3, the sensor 15 detects that the optical pickup 1 is a laser at a specific radial position d of the disk 90. The sensor detects that the irradiation is in a position state.
Information detected by the sensor 15 is supplied to the system controller 10. The system controller 10 determines based on the detection information from the sensor 15 whether or not the optical pickup 1 is in a position state in which recording / reproduction can be performed with respect to the radial position d of the disk 90 (position d from the center of the disk). it can.

1 has been described as a disk drive device connected to the host device 100, the disk drive device of the present invention may have a form that is not connected to other devices. In this case, an operation unit and a display unit are provided, and the configuration of the interface part for data input / output is different from that in FIG. That is, it is only necessary that recording and reproduction are performed in accordance with a user operation and a terminal unit for inputting / outputting various data is formed.
Of course, various other examples of the configuration of the disk drive device are conceivable. For example, an example of a read-only device is also conceivable.

FIG. 2 shows a configuration example of the PLL unit 27 in the wobble processing system 6.
The PLL unit 27 is configured to have a two-stage PLL processing system as the frequency pulling unit 28 and the phase pulling unit 29. The wobble signal is converted into binary values of H and L by the binarization circuit 38 and input to the frequency acquisition unit 28 and the phase acquisition unit 29.
The frequency pulling unit 28 includes a speed comparator 30, a PI filter 31, and a VCO (Voltage Controlled Oscillator) 32. In the speed comparator 30, the frequency pull-in unit 28 performs frequency comparison between the wobble signal from the A / D conversion unit 24 and the oscillation frequency of the VCO 32, and the frequency error obtained as a result of the comparison is averaged by the PI filter ( Integrated) to become the control voltage of the VCO 32. As a result, the oscillation frequency of the VCO 32 is drawn into the wobble signal frequency.
The phase pulling unit 29 includes a phase comparator 33, a PI filter 34, a limiter 35, a VCO 36, and a register 37.
Then, the phase comparison between the wobble signal and the oscillation frequency of the VCO 36 is performed by the transfer comparator 33, the phase error obtained as a result of the comparison is averaged (integrated) by the PI filter, and the control voltage of the VCO 36 is obtained via the limiter 35. Become. The limiter 35 limits the control voltage with respect to the VCO 36 using the control voltage ± α subjected to the frequency pull-in in the frequency pull-in unit 28 as a limit value. The oscillation output of the VCO 36 is the wobble clock CKw.

That is, the PLL unit 27 generates a wobble clock CKw by performing frequency acquisition and phase acquisition on the wobble signal.
Here, the voltage applied to the VCO 36 is stored in the register 37. The applied voltage value reflected in the register 37 is a value corresponding to the wobble frequency.
Therefore, the system controller 10 can detect the wobble signal frequency by multiplying the value stored in the register 37 by a predetermined coefficient.
The fact that the frequency error component is averaged by the PI filter 31 and that the wobble signal frequency can be detected by multiplying the control voltage for the VCO 36 by a coefficient means that the system controller 10 can increase the wobble signal frequency in one trial. It means that it can be detected accurately.

Hereinafter, the recording capacity determination operation of the disk 90 according to this example will be described.
Hereinafter, in order to make the explanation easy to understand, it is considered to specifically determine the capacity of three types of recording capacities of 23 GB (Giga Byte), 25 GB, and 30 GB. The disks 90 having the respective capacities are hereinafter referred to as a 23 GB disk, a 25 GB disk, and a 30 GB disk.

The disk drive device must control the linear velocity so that the frequency of the wobble signal read from the disk 90 is always the predetermined value “F”. Therefore, the spindle servo circuit 12 performs spindle servo control (CLV control) that increases the rotational speed of the spindle motor 2 as the inner peripheral side of the disk 90 is read and decreases the rotational speed toward the outer peripheral side.
Considering a disk 90 with a different recording capacity, if the linear velocity when reading a 23 GB disk is “V”, the linear velocity when reading a 25 GB disk is “(23/25) V”. If the linear velocity when reading a 30 GB disk is set to “(23/30) V”, the wobble signal frequency can be maintained at the predetermined value “F” regardless of the difference in capacity.
Conversely, if the 25 GB disk is mounted when the spindle motor 2 is rotating at the speed for 23 GB disk, the wobble signal frequency to be read is “(23/25) F”, and the 30 GB disk is If it is attached, the wobble signal frequency is “(23/30) F”.

This is collectively shown in FIG.
In FIG. 4, when the optical pickup 1 is at the radial position d shown in FIG. 3, when the rotational speed of the spindle motor 2 is set to a speed for a 23 GB disk, or to a speed for a 25 GB disk, a 30 GB disk is used. The wobble signal frequency observed according to the recording capacity of the loaded disc 90 is shown for each of the cases where the speed is set to the above-mentioned speed.

When the capacity is determined, it is determined in advance how many GB disk speed the spindle motor 2 is rotated. For example, if it is determined that the capacity determination is performed at the rotational speed for the 23 GB disk, the system controller 10 moves the optical pickup 1 to the radial position d in FIG. 3, and the wobble signal frequency read at this time is F when the 23 GB disk is loaded. The spindle speed is controlled so that
Since the system controller 10 knows by itself how many GB disks the spindle motor 2 is rotating, the capacity of the disk can be determined from the relationship shown in FIG.
For example, when the spindle motor 2 is rotated at a speed for a 23 GB disk and the frequency of the read wobble signal is (23/30) F, it is determined that the currently loaded disk 90 is a 30 GB disk. it can.
If the frequency of the read wobble signal is F when the spindle motor 2 is rotated at a speed for a 25 GB disk, the currently loaded disk can be identified as a 25 GB disk.

A processing example of the system controller 10 for performing such determination is shown in FIG.
The system controller 10 first controls the transfer of the optical pickup 1 in step F100. In step F101, the detection signal of the sensor 15 is monitored. That is, the system controller 10 instructs the optical block servo circuit 11 to execute sled movement so that the optical pickup 1 is positioned at a specific radial position d.
When the detection signal of the sensor 15 is turned on in step F101 and it is confirmed that the optical pickup 1 has been transferred to the radial position d, in step F102, the spindle servo circuit 12 is instructed to rotate, for example, for a 23 GB disk. That is, when a 23 GB disk is loaded, the rotation speed at which a predetermined linear velocity is obtained at the radial position d is indicated. As a result, the spindle motor 2 is rotationally driven at a rotational speed for a 23 GB disk.

  In this state, the system controller 10 measures the wobble signal frequency in step F103. In other words, the optical pickup 1 is started to irradiate the laser, and the optical block servo circuit 11 is instructed to perform focus pull-in, focus servo settling, and tracking servo settling, thereby setting a reproduction operation state. Then, during the reproduction operation, the control voltage value stored in the register 37 of the PLL unit 27 is read and multiplied by a predetermined coefficient value to measure the wobble signal frequency.

When the wobble signal frequency is measured, it may be confirmed whether the frequency value is F, (25/23) F, or (30/23) F. That is, the relationship shown in FIG. 4 (in the case of the rotational speed for a 23 GB disk) may be applied.
If the wobble signal frequency = F, the process proceeds from step F104 to F105, and the capacity of the loaded disk 90 is determined to be 23 GB.
If the wobble signal frequency = (25/23) F, the process proceeds from step F106 to F107, and the capacity of the loaded disk 90 is determined to be 25 GB.
If the wobble signal frequency = (30/23) F, the process proceeds from step F108 to F109, and the capacity of the loaded disk 90 is determined to be 30 GB.

  After determining the recording capacity of the disk 90 in this manner, the system controller 10 may then change the setting of the spindle rotation speed and the PLL center frequency according to the determined recording capacity.

  If the value of the wobble signal frequency is not any of F, (25/23) F, and (30/23) F, the process proceeds to step F110 and may be processed as a disk error. For example, a disk ejection process or a disk error notification to the host device 100 is performed as a disk incompatible with the present disk drive device.

In the process of FIG. 5, the spindle motor 2 is rotated at the rotational speed for the 23 GB disk in step F102. Of course, the spindle motor 2 is rotated at the rotational speed for the 25 GB disk or the rotational speed for the 30 GB disk. Rotation may be performed.
As can be seen from FIG. 4, when the spindle motor 2 is rotated at the rotational speed for the 25 GB disk in step F102, the measured wobble is 23 GB if the measured wobble signal frequency is (23/25) F. If the signal frequency is F, a 25 GB disk may be determined, and if the measured wobble signal frequency is (30/25) F, the process may be determined as a 30 GB disk.
When the spindle motor 2 is rotated at the rotational speed for the 30 GB disk in step F102, if the measured wobble signal frequency is (23/30) F, the measured wobble signal frequency is (25 / 30) If it is F, a 25 GB disk may be determined, and if the measured wobble signal frequency is F, it may be determined that the disk is a 30 GB disk.

  As described above, the function of determining the recording capacity of the loaded disk 90 without depending on the PIC information can be realized. This disc recording capacity discriminating function is possible only by adding software without adding new hardware.

  However, in reality, it may be difficult to determine the capacity by the processing of FIG. 5 using the relationship of FIG. 4 as it is, and there are points to consider. This will be described below.

<Consideration 1: Variation in mounting position of optical head position sensor>
First, the sensor 15 for detecting the position of the optical pickup 1 shown in FIG. When the variation width is α, the mounting position of the sensor 15 is in the range of d ± α. Therefore, the wobble signal frequency variation due to the mounting position variation is
{(D + α) / d} F ≧ (frequency of wobble signal) ≧ {(d−α) / d} F
It becomes the range. Note that the value of α is guaranteed in advance by a manufacturing standard or the like.

<Consideration 2: Disk eccentricity>
When the disk 90 is mounted on the spindle motor 2, it is only necessary that the center of the disk 90 and the center of the spindle motor axis always coincide with each other. This deviation is called eccentricity. An error occurs in the linear velocity due to the eccentricity. If this error is β [%], the linear velocity error due to eccentricity is ± β [%]. Note that the value of β is also guaranteed in advance by a manufacturing standard or the like.

<Consideration 3: Accuracy of spindle speed control>
Depending on the accuracy of the rotational speed control of the spindle motor 2, jitter and a steady error occur in the linear velocity of the disk. Since it is difficult to make these zero, normally, the design is performed on the assumption that there is an error in a certain range in the linear velocity by the spindle velocity control.
When this error is γ [%], the linear velocity error by the spindle speed control is ± γ [%]. Note that the value of γ is also guaranteed in advance by a manufacturing standard or the like.

<Consideration 4: Variation due to linear velocity error>
From the above consideration points 2 and 3, the frequency variation of the wobble signal due to the linear velocity error is
F {1+ (β / 100) + (γ / 100)} ≧ (frequency of wobble signal) ≧ F {1- (β / 100) − (γ / 100)}
It becomes the range.
Therefore, from the above consideration points 1 and 4, the value CmaxF when the frequency of the wobble signal varies highest is:
CmaxF = {(d + α) / d} F × {1+ (β / 100) + (γ / 100)}
= {(D + α) / d} {1+ (β + γ) / 100)} F
On the contrary, the value CminF when the lowest variation is
CminF = {(d-α) / d} F × {1- (β / 100)-(γ / 100)}
= {(D-α) / d} {1- (β + γ) / 100)} F
It is assumed.

FIG. 6A, FIG. 6B, and FIG. 6C are obtained by correcting FIG. 4 in consideration of these consideration points 1-4.
FIG. 6A shows the maximum value and the minimum value of the measured wobble signal frequency according to the capacity of the loaded disk 90 when the rotational speed for the 23 GB disk is used.
FIG. 6B shows the maximum value and the minimum value of the measured wobble signal frequency according to the capacity of the loaded disk 90 when the rotational speed for the 25 GB disk is used.
FIG. 6C shows the maximum value and the minimum value of the measured wobble signal frequency according to the capacity of the loaded disk 90 when the rotational speed is for a 30 GB disk.

An algorithm for discriminating the disk capacity using the relationship shown in FIGS. 6A, 6B, and 6C will be described below.
Since the system controller 10 knows by itself how many GB disk rotation speed the spindle motor 2 is rotating, if the frequency measurement value of the wobble signal is fmes, it can be determined as follows.

First, when the spindle motor 2 is set to a rotational speed for a 23 GB disk, as shown in FIG.
Xmax = CmaxF
Xmin ＝ CminF
Ymax = CmaxF × (25/23) F
Ymin = CminF × (25/23) F
Zmax = CmaxF × (30/23) F
Zmin = CminF × (30/23) F
First, an intermediate value between Xmax and Ymin is used as a threshold value to compare whether the frequency measurement value fmes is larger or smaller. That is,
fmes ≤ (Xmax + Ymin) / 2
If so, it is determined that the loaded disk 90 is a 23 GB disk. on the other hand,
fmes> (Xmax + Ymin) / 2
If the frequency measurement value fmes is equal to or smaller than the threshold value, the frequency value fmes is compared with the threshold value. That is,
fmes ≤ (Ymax + Zmin) / 2
If so, it is determined that the loaded disk 90 is a 25 GB disk. on the other hand,
fmes> (Ymax + Zmin) / 2
If so, it is determined that the loaded disk 90 is a 30 GB disk.

When the spindle motor 2 has a rotational speed for a 25 GB disk, as shown in FIG.
Xmax = CmaxF × (23/25) F
Xmin = CminF × (23/25) F
Ymax ＝ CmaxF
Ymin ＝ CminF
Zmax = CmaxF × (30/25) F
Zmin = CminF × (30/25) F
And First, an intermediate value between Xmax and Ymin is used as a threshold value to compare whether the frequency measurement value fmes is larger or smaller. That is,
fmes ≤ (Xmax + Ymin) / 2
If so, it is determined that the loaded disk 90 is a 23 GB disk. on the other hand,
fmes> (Xmax + Ymin) / 2
If the frequency measurement value fmes is equal to or smaller than the threshold value, the frequency value fmes is compared with the threshold value. That is,
fmes ≤ (Ymax + Zmin) / 2
If so, it is determined that the loaded disk 90 is a 25 GB disk. on the other hand,
fmes> (Ymax + Zmin) / 2
If so, it is determined that the loaded disk 90 is a 30 GB disk.

When the spindle motor 2 has a rotational speed for a 30 GB disk, as shown in FIG.
Xmax = CmaxF × (23/30) F
Xmin = CminF × (23/30) F
Ymax = CmaxF × (25/30) F
Ymin = CminF × (25/30) F
Zmax ＝ CmaxF
Zmin = CminF
And First, an intermediate value between Xmax and Ymin is used as a threshold value to compare whether the frequency measurement value fmes is larger or smaller. That is,
fmes ≤ (Xmax + Ymin) / 2
If so, it is determined that the loaded disk 90 is a 23 GB disk. on the other hand,
fmes> (Xmax + Ymin) / 2
If the frequency measurement value fmes is equal to or smaller than the threshold value, the frequency value fmes is compared with the threshold value. That is,
fmes ≤ (Ymax + Zmin) / 2
If so, it is determined that the loaded disk 90 is a 25 GB disk. on the other hand,
fmes> (Ymax + Zmin) / 2
If so, it is determined that the loaded disk 90 is a 30 GB disk.

FIG. 7 shows the capacity determination processing of the system controller 10 by taking as an example the case of the rotational speed for the 23 GB disk in FIG.
First, the system controller 10 controls the transfer of the optical pickup 1 in step F200. In step F201, the detection signal of the sensor 15 is monitored. That is, the system controller 10 instructs the optical block servo circuit 11 to execute sled movement so that the optical pickup 1 is positioned at a specific radial position d.
When it is confirmed in step F201 that the detection signal of the sensor 15 is turned on and the optical pickup 1 has been transferred to the radial position d, in step F202, the spindle servo circuit 12 is instructed to rotate the 23 GB disk. That is, when a 23 GB disk is loaded, the rotation speed at which a predetermined linear velocity is obtained at the radial position d is indicated. As a result, the spindle motor 2 is rotationally driven at a rotational speed for a 23 GB disk.

  In this state, in step F203, the system controller 10 measures the wobble signal frequency. In other words, the optical pickup 1 is started to irradiate the laser, and the optical block servo circuit 11 is instructed to perform focus pull-in, focus servo settling, and tracking servo settling, thereby setting a reproduction operation state. Then, during the reproduction operation, the control voltage value stored in the register 37 of the PLL unit 27 is read and multiplied by a predetermined coefficient value to measure the wobble signal frequency.

When the wobble signal frequency is measured, first, in step F204, it is determined whether or not the frequency measurement value fmes is one of fmes <Xmin or fmes> Zmax.
This is a case where the frequency measurement value fmes is a value that is not assumed at all, and if it falls under these, the process proceeds to step F210 and is processed as a disk error. For example, a disk ejection process or a disk error notification to the host device 100 is performed as a disk incompatible with the present disk drive device.

If neither fmes <Xmin nor fmes> Zmax, the frequency measurement value fmes is compared with a threshold value (Xmax + Ymin) / 2 in step F205.
And
fmes ≤ (Xmax + Ymin) / 2
If so, the process proceeds to step F206, and it is determined that the loaded disk 90 is a 23 GB disk. On the other hand, in step F205,
fmes> (Xmax + Ymin) / 2
If it is determined, the process proceeds to step F207, and the frequency measurement value fmes is compared with a threshold value (Ymax + Zmin) / 2. And
fmes ≤ (Ymax + Zmin) / 2
If so, the process proceeds to step F208 to determine that the loaded disk 90 is a 25 GB disk. on the other hand,
fmes> (Ymax + Zmin) / 2
If so, the process proceeds to step F209 to determine that the loaded disk 90 is a 30 GB disk.

After determining the recording capacity of the disk 90 in this manner, the system controller 10 may then change the setting of the spindle rotation speed and the PLL center frequency according to the determined recording capacity.
In this example, the spindle motor 2 is rotated at the rotational speed for the 23 GB disk. However, the same applies to the case where the spindle motor 2 is rotated at the rotational speed for the 25 GB disk or the rotational speed for the 30 GB disk in step F202. Capacity discrimination can be performed by processing.

  As described above, by comparing the frequency measurement value of the wobble signal with the fixed threshold values (Xmax + Ymin) / 2 and (Ymax + Zmin) / 2 prepared in advance, the disc capacity can be discriminated without depending on the PIC information. Can be performed.

As described above, the recording capacity of the disk 90 is obtained as a measurement value of the wobble signal frequency by performing reproduction at a specific rotational speed (for example, a rotational speed for a 23 GB disk) at the radial position d as described in the embodiment. A value corresponding to is detected, and the recording capacity of the loaded disc 90 can be determined. In other words, the recording capacity of the disc can be determined without relying on management information such as PIC, and the setting (spindle rotation speed setting and PLL center frequency setting) can be made according to the determination result. Even if the disc 90 is loaded, it can be properly reproduced.
For the sake of explanation, three types of discrimination of 23 GB disc, 25 GB disc, and 30 GB disc have been mentioned. However, even when other capacities exist, capacity discrimination can be executed by deriving the relationships corresponding to FIGS. .
Further, the position d of the optical pickup 1 at the time of capacity determination may be arbitrarily determined.

For the capacity determination process of this example, the system controller 10 need only be able to execute the process of FIG. 5 or 7 without adding new hardware, that is, only by adding microcomputer software. The capacity determination process of this example can be realized. Therefore, there is no burden on the hardware configuration and the implementation is easy.
Furthermore, since the frequency measurement of the wobble signal can be realized by the PLL unit 27 having the configuration shown in FIG. Therefore, it is possible to realize a disk drive device that can perform recording or reproduction quickly after loading the disk.

1 is a block diagram of a disk drive device according to an embodiment of the present invention. It is a block diagram of the PLL unit of the embodiment. It is explanatory drawing of the sensor of the position of the optical pick-up of embodiment. It is explanatory drawing of the capacity | capacitance discrimination | determination of embodiment. It is a flowchart of the capacity | capacitance discrimination | determination process of embodiment. It is explanatory drawing of the capacity | capacitance discrimination | determination of embodiment. It is a flowchart of the capacity | capacitance discrimination | determination process of embodiment. It is explanatory drawing of the reading operation | movement of PIC information. It is explanatory drawing of the relationship between a PLL frequency and RF signal frequency.

Explanation of symbols

  1 optical pickup, 2 spindle motor, 3 thread mechanism, 4 matrix circuit, 5 reproduction signal processing system, 6 wobble processing system, 10 system controller, 11 optical block servo circuit, 12 spindle servo circuit, 15 sensor, 27 PLL section, 28 Frequency pull-in section, 29 Phase pull-in section, 37 registers

Claims (4)

A head unit for reading information from a disk recording medium on which a wobbling groove is formed;
A rotational drive unit for rotationally driving the disk recording medium at a constant linear velocity;
A wobble frequency measuring unit that measures the frequency of a wobble signal read to the head unit as information on the wobbling groove of the disk recording medium;
The head unit is brought into a state in which information is read out from the loaded disk recording medium at a specific radial position, and the rotation drive unit is rotated at a specific speed. At that time, the wobble frequency measurement unit A control unit for determining the recording capacity of the loaded disk recording medium based on the detected frequency;
A disk drive device comprising: The wobble frequency measurement unit
A frequency pull-in unit that pulls in the oscillation frequency with respect to the average frequency of the wobble signal read out by the head unit;
In a state where the frequency pull-in is performed in the frequency pull-in unit, a phase pull-in unit that pulls in the phase of the oscillation frequency for the wobble signal, and
2. The disk drive device according to claim 1, wherein an input voltage value of the voltage controlled oscillator in the phase pulling unit is detected as a value corresponding to a wobble frequency. The control unit
Set a threshold for the frequency of the wobble signal measured by the wobble frequency measurement unit,
2. The disk drive device according to claim 1, wherein a recording capacity of the loaded disk recording medium is determined based on a result of comparing the frequency measured by the wobble frequency measuring unit with the threshold value. As a disc recording capacity determination method of a disc drive device that records or reproduces information on a disc recording medium on which a wobbling groove is formed,
Setting a head unit for reading information from a disk recording medium to a state in which information is read from a loaded disk recording medium at a specific radial position;
A step of rotating the loaded disk recording medium at a specific speed by a rotation driving unit;
Measuring the frequency of a wobble signal read by the head unit as wobbling groove information of the loaded disk recording medium;
Determining the recording capacity of the loaded disk recording medium based on the measured frequency of the wobble signal;
A disc recording capacity discrimination method comprising:

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