JPH1186424A - Controller for optical disk device and its control method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the accuracy of the movement control of an optical pickup section in seek control relating to a controller for an optical device and a control method therefor. SOLUTION: This controller has a TES signal forming section 6 and a control means 1 for forming a control signal of a moving body moving on an optical disk in seek control. This control means 7 has a TZC signal forming section 6 which forms a TZC signal based on the TES signal and a control signal forming section which decides the kind of the optical disk medium to be set, detects an optimum phase A for a medium A for which the control signal formed in accordance with the phase A of the TZC signal is optimum or an optimum phase signal B for a medium B for which the control signal formed in accordance with the phase B of the TZC signal is optimum and forms the control signal of a moving body driving section in accordance with the phase A when the optical medium A is set and forms the control signal of the moving body driving section 3 in accordance with the phase B when the optical disk of the medium B is set.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a control device and a control method for an optical disk device capable of driving optical disks having different media such as a magnetic optical disk (MO) and a compact disk (CD).

[0002]

2. Description of the Related Art When performing seek control, an optical disk apparatus generates a tracking error signal (TES signal) of an optical pickup unit such as a focus lens of a laser beam based on a reflected signal from a driven optical disk. That T
The moving speed of the actuator is obtained based on the ES signal, and a speed control signal is generated from the difference from the target speed to control the optical pickup unit. At this time, a zero-cross signal (TZC signal) is generated from the TES signal, and the moving speed of the optical pickup unit is obtained from the edge interval (time) and the track pitch (distance) of the signal.

FIG. 8 is an explanatory diagram of the prior art. Fig. 8 (a)
Is a TES signal. FIG. 8B shows a TZC signal. FIG. 8C is an explanatory diagram of a driving method of the optical pickup unit of the optical disk device.

[0004] In FIG. 8C, in FIG.
Is an optical disk.

[0005] An optical pickup unit 101 moves on the optical disk 100 and receives the reflected light from the optical disk 100. 105 is a focus lens.

Reference numeral 106 denotes a reflecting mirror. 110 is a laser emitting unit. Reference numeral 111 denotes a light receiving unit,
It receives reflected light from zero.

Reference numeral 116 denotes a TES signal circuit which generates a tracking error signal (TES signal) based on the reflected light from the optical disc 100. 117 is TZC
A signal circuit for generating a zero cross signal (TZC signal) based on the TES signal.

Reference numeral 118 denotes a control signal generation circuit,
The moving speed of the optical pickup unit is obtained based on the C signal,
This is to generate a control signal for a driving device of the optical pickup unit.

In the configuration shown in FIG.
Is reflected by the reflecting mirror 106 and irradiated on the optical disk. The light reflected on the optical disc 100 is reflected by the reflecting mirror 106 and received by the light receiving unit 111.

The TES signal circuit is a TES signal having a periodic property determined according to a track pitch based on an optical signal by reflected light when the optical pickup unit 101 moves across a track of an optical disk during a seek.
Generate (a). The TZC signal circuit 117 generates a TZC signal based on the TES signal.

The control signal generation circuit 118 calculates .DELTA.t / L based on the edge interval (.DELTA.t) of the TZC signal and the track pitch (L) of the optical disk to obtain the moving speed of the optical pickup unit, and calculates the moving speed of the optical pickup unit. A control signal that gives an optimum control speed is generated based on the difference.

[0012]

As described above, when controlling the movement of the optical pickup unit, it is necessary to accurately determine the moving speed of the optical pickup unit.
The generation of the ES signal and the TZC signal is important. However, M
O has a problem in TES generation because of the use of a light beam having a small spot diameter for MO for CDs because of the medium structure in which embossed pits are present on the lands. It is necessary to consider how to use the signal. For this reason, the phase of the TZC signal that accurately reflects the position information of the optical pickup unit differs depending on the type of the medium. On the other hand, when performing seek control of the optical pickup unit, it is necessary to accurately determine the moving speed of the optical pickup unit across the optical disk. Conventionally, the moving speed of the optical pickup section crossing the track is determined based on the TZC signal without considering such a situation.
Therefore, in the conventional seek control, an error occurs in the movement control of the optical pickup unit depending on the type of the medium.

This point will be described in detail with reference to FIGS. FIG. 2 shows the structure of the MO medium and its TES signal (MO signal).
-TES). FIG. 2A shows the structure of the MO medium.
In MO, there is a group (guide groove) between lands. Embossed pits are formed in the ID portion of the land to serve as a header. Then, there is a data recording section for recording data on the front surface, followed by a mirror section on which data is not recorded, following the header on the same track.

For such an MO, a TES signal is generated by a push-pull method (the push-pull method will be described later).
Signals tend to be unstable. Further, the generation of the TES signal becomes unstable due to the reflection in the mirror surface portion and the data recording portion. However, the guide groove between the lands
In, the generation of the TES signal is stable. Therefore,
In order to accurately determine the moving speed of the optical pickup unit in a seek based on the TES signal generated by the push-pull method, time measurement is performed using the phase (timing) of the TZC signal reflecting the guide groove (group). Is good.

FIG. 2B shows a TES signal generated when seeking in the seek direction from left to right in the figure. When the seek direction changes from right to left, the polarity of the TES signal is opposite to that in FIG.

FIG. 3 shows the structure of a CD medium and its TES signal (CD-TES). FIG. 3A shows the structure of a CD medium. CDs have no lands, and data is recorded in pits on tracks. TE for a CD medium with the beam spot diameter of the laser wavelength used for recording and reproduction of the MO medium
When the S signal is generated, the push-pull method cannot generate a TES signal when the pit depth is 1/4 of the laser wavelength (the spot diameter of the laser beam with respect to the MO is smaller than the optimum spot diameter of the CD). Therefore, a heterodyne method is used to generate a TES signal of a CD in an optical disk device capable of driving a heterogeneous medium using an optimum spot diameter for the MO (the heterodyne method will be described later). In this case, since the track pitch of the CD is wider than the spot diameter, detection by the heterodyne method is limited in a mirror portion existing between pits, and generation of a TES signal becomes unstable. Therefore, the TES signal is generated stably in the pits on the CD medium. Therefore, when measuring the seek speed of the optical pickup unit of the CD medium, it is preferable to monitor the TZC signal reflecting the pit.

FIG. 3B shows a TES signal generated when the CD is sought from left to right in the figure. When the seek direction changes from left to right, the polarity of the TES signal is opposite to that in FIG.

FIG. 4 shows the relationship between the TES signal and the TZC signal when the MO medium and the CD medium are compared in the same seek direction. In FIG. 4, (a) shows the T of the MO.
This is an ES signal.

(B) is the TZC signal, which is the TES of the MO.
It is generated based on the signal. (c) is the TE of the CD
This is the S signal.

(D) is the TZC signal, which is the TES of the CD.
It is generated based on the signal. In FIG. 4A, point A is the timing of crossing the guide groove (groove) in the MO medium. This timing corresponds to the falling edge of the TZC signal as shown in FIG.
Is a stable reflection of the group.

In FIG. 4C, point B is the timing of crossing a pit on a CD medium. This timing corresponds to the rising edge of the TZC signal and stably reflects the pits of the CD, as shown in FIG.

As described above, when the moving speed in the seek of the optical pickup unit is obtained based on the TES signal as shown in FIG. 4, the inter-track distance is determined for MO based on the timing of the falling edge of the TZC signal. The speed of movement of
For a CD, it is preferable to determine the moving speed between tracks based on the timing of the rising edge of the TZC signal. In the case where the seek direction is opposite, in FIG.
Since the polarities of the S signal and the TZC signal are different, the optimum edges are also reversed. That is, the rising edge for MO,
The falling edge is good for CD.

As described above, without considering the type of medium, T
If the moving speed in the seek control of the optical pickup unit is obtained based on the ZC signal, an error may occur depending on the medium. SUMMARY OF THE INVENTION It is an object of the present invention to provide a control apparatus and a control method for an optical disc apparatus capable of obtaining a moving speed of an optical pickup unit in seek control at an optimum phase of a TZC signal according to a medium and performing movement control with a small error. .

[0024]

A control device according to the present invention includes a TES signal generator for generating a tracking error signal for an optical disc, a zero-cross signal based on the tracking error signal in seek control, and a zero-cross signal based on the zero cross signal. Control means for generating a control signal for driving a moving body moving on the optical disk, wherein the control means generates a zero-cross signal based on the tracking signal.
The C signal generation unit determines the type of the optical disk medium set, and determines the control signal generated based on the phase A of the zero cross signal based on the optimum phase A for the optical disk medium A or the phase B of the zero cross signal. The optimum phase B for the optical disk medium B having the optimum generated control signal is detected, and when the optical disk of the medium A is set, the control signal of the moving body driving unit is generated based on the phase A of the zero cross signal. And a control signal generator for generating a control signal for the moving body driver based on the phase B of the zero-cross signal when the optical disk of the medium B is set.

According to the control method of the present invention, a tracking error signal of an optical disk is generated, a zero-cross signal is generated based on the tracking signal, a type of the optical disk medium set is determined, and a phase A of the zero-cross signal is determined. Optical disc medium A in which the generated control signal is optimal
The optimum phase B for the optical disc medium B in which the control signal generated based on the optimum phase A or the phase B of the zero-cross signal is optimum is detected, and when the optical disc of the medium A is set, the movement based on the phase A is performed. A control signal is generated for generating a control signal for the body driving unit, and for generating a control signal for the moving body driving unit based on the phase B when the optical disk of the medium B is set.

FIG. 1 is a diagram showing a basic configuration of the present invention.
In FIG. 1, reference numeral 1 denotes a heterogeneous medium driving device which can drive an optical disk having a different medium.

Reference numeral 2 denotes a medium driving unit, which is a driving unit for driving an optical disk. Reference numeral 3 denotes a moving body driving unit that drives an optical pickup unit such as a focus lens.

Reference numeral 4 denotes an optical signal input unit for inputting an optical signal output from the heterogeneous medium driving device 1. 5
Is a control device.

Reference numeral 6 denotes a TES signal generation unit for generating a TES signal based on the optical signal input to the optical signal input unit 4. 7 is a control means.

Reference numeral 10 denotes a TZC signal generation unit,
The TZC signal is generated based on the TES signal generated by the signal generator 6. Reference numeral 15 denotes a control signal generation process for generating a control signal for driving the moving body driving unit 3 in the seek control, and the moving speed of the moving body driving unit 3 based on the time interval of the edge of the TZC signal. Is a process for generating an optimal control signal by comparing the calculated value with a target value.

Numeral 16 denotes a process for determining an optimum phase of the TZC signal, and an optimum phase (edge) for the medium A of the TZC signal.
This is a process for detecting the optimum phase (edge) of the TZC signal for the medium B.

Reference numeral 17 denotes a medium type determination process for determining the type of the medium of the optical disk set in the heterogeneous medium drive 1. The operation of the basic configuration of the present invention shown in FIG. 1 will be described.

The optical signal input unit 4 inputs an optical signal reflected from the optical disk of the heterogeneous medium drive 1. The TES signal generator 6 generates a TES signal based on the optical signal input to the optical signal input unit 4. The TZC signal generation unit 10
T based on the TES signal generated by the ES signal generator 6
Generate a ZC signal.

The control signal generator 14 determines the type of the medium and determines the optimum phase of the TZC signal according to the type of the medium. Then, based on the optimum phase of the TZC signal, a moving speed at which the moving body driving unit 3 moves between tracks is obtained, and an optimum control signal for driving the moving body driving unit 3 is generated based on the moving speed.

According to the present invention, in the seek control of an optical disk apparatus capable of driving different types of media, the phase (edge) of the TZC signal that is optimal for each medium is detected, and the optical pickup unit (edge) is detected based on the detected phase. Since the moving body is controlled, a control signal with a small control error can be generated. Therefore, the performance of the optical disk device can be improved.

[0036]

FIG. 5 shows an embodiment of the apparatus configuration of the present invention. In FIG. 5, reference numeral 31 denotes an MO host IF circuit, which is an interface for MO with a host computer (not shown).

Reference numeral 32 denotes an MO signal control circuit.
Read control and write control. 34
Denotes a laser light emitting unit, which is a unit of a laser light source.

Reference numeral 35 denotes a CD host IF circuit, which is an interface for a CD with a host computer (not shown). Numeral 36 denotes a CD signal control circuit for controlling read of a CD.

Numeral 38 denotes a light receiving section, which is an optical pickup section for receiving the laser light emitted by the laser emitting section 34 and reflected by the medium. Reference numeral 40 denotes a TES signal circuit, and a TES signal circuit based on the optical signal received by the light receiving unit 38
This is for generating an ES signal.

Reference numeral 42 denotes a control unit for controlling the driving of the optical pickup driving device 43. The control unit 42 generates and monitors a TZC signal, determines a seek direction, monitors an edge of the TZC, and monitors a moving speed of the light receiving unit 38. It performs calculations and the like.

Reference numeral 43 denotes an optical pickup driving device.
The optical pickup 56 is driven. A motor driving device 44 drives a motor of the optical disk device.

Numeral 45 is a medium sensor for detecting the type of medium of the optical disk set in the optical disk device. 46 is a sensor adapter.

Reference numeral 50 denotes an audio amplifier. A main MPU 51 controls the operation of each unit of the control device 5.

Reference numeral 52 denotes a ROM. 53 is a RAM. Reference numeral 54 denotes a medium type determination unit that determines the type of the medium of the optical disk set.

Reference numeral 46 denotes a sensor adapter, which is an adapter for the medium sensor 45. Reference numeral 56 denotes an optical pickup unit, which is an optical unit that moves on a medium such as a focus lens.

Note that the control means of FIG.
It includes a control unit 42 and a main MPU 51. FIG.
The operation of the configuration will be described.

In the configuration shown in FIG. 5, each unit operates under the control of the MPU 51. The medium sensor 45 determines the medium type, and the type is notified to the host computer via the MO host IF circuit 31 or the CD host IF circuit 35.

A command for the MO from the host computer such as an interrupt control signal from the host computer (not shown) is received by the MO host IF circuit 31,
A command for the CD is received by the CD host IF circuit 35. In accordance with each command, the MO signal control circuit 32 and the CD signal control circuit 36 start operating,
In the MO mode, writing or reading of MO data is executed. In the CD mode, reading of a CD is executed.

The laser light emitting section 34 emits a laser beam, irradiates the optical disk via the optical pickup section 56, and the reflected light is received by the light receiving section 38 via the optical pickup section 56.

In the write mode for the MO, the laser light emitting section 34 generates write light under the control of the MO signal control circuit 32, and data is recorded on the MO medium by the optical pickup section 56. In the data reading mode of the MO, the light receiving unit 38 receives the reflected light of the laser beam incident on the MO via the optical pickup unit 56, and the read data is controlled by the signal control circuit 32 for the MO. It is transmitted to the host computer via the MO host IF circuit.

Similarly, in the CD reading mode,
The light reflected by the light receiving section 38 is transmitted through the optical pickup section 56
Are received, controlled by the CD signal control circuit 36, and read. And the read data is CD host I
The data is transmitted to the host computer via the F circuit 35 or transmitted to the audio amplifier 50 and output as audio.

In the seek control of the optical pickup section, the optical pickup section 56 moves in a direction crossing the track of the optical disk, and the laser beam reflected by the medium of the optical disk is received by the light receiving section 38. Then, the optical signal received by the light receiving section 38 is input to the TES signal circuit 40. TE
S signal circuit is TES signal generator for MO and TES for CD
And a signal generation circuit (see FIG. 7). And M
O TES signal (TES1) and CD TES signal (TE
An S signal 2) is generated. Then, the optimal TES signal corresponding to the medium type is selected by the switching signal corresponding to the medium type, and is transferred to the control unit 42.

In the control section 42, the TES signal circuit 40
, A TZC signal is generated for the TES signal transferred from. Then, the control unit 42 selects an optimum edge of the TZCS signal according to the type of the medium, and calculates a movement time interval between tracks of the optical pickup unit 56 based on the edge. Then, the moving speed of the optical pickup unit 56 is obtained from the moving time and the track pitch of the optical disk of the set medium type. Then, a control signal of the optical pickup driving device 43 for controlling the movement of the optical pickup unit 56 is generated, and the optical pickup unit 56 is controlled.
Is controlled to move.

FIG. 6 shows an embodiment of the configuration of the control unit according to the present invention. In FIG. 6, reference numeral 34 denotes a laser emitting unit.

Reference numeral 38 denotes a light receiving section. 40 is a TES signal circuit. 42 is a control unit.

Reference numeral 43 denotes an optical pickup driving device.
The optical pickup 56 is driven. 56 is an optical pickup unit.

Reference numeral 82 denotes a focus lens. 83 is a reflecting mirror. Reference numeral 14 denotes a control signal generator.

Reference numeral 60 denotes an input section for inputting a signal. Reference numeral 61 denotes a TZC signal generation unit,
The TZC signal is generated based on the TES signal generated by the ES signal generation unit or the CD TES signal generation unit.

Reference numeral 62 denotes a seek direction determination unit which determines the seek direction of the light receiving unit (whether it is moving outward or inward).

Reference numeral 64 denotes an edge interval determination unit which determines an edge interval and detects a moving time (ΔT) between tracks. 64 'is a medium type determination unit.

Reference numeral 65 denotes a speed calculating unit for calculating the moving speed of the light receiving unit based on the moving time ΔT between tracks and the track pitch L. Reference numeral 66 denotes a movement control signal generation unit which generates a control signal for performing speed control or the like for the optical pickup driving device 43.

An output unit 67 outputs a control signal to the optical pickup driving device 43. 70 is D
The SP is for controlling each part of the control unit 42.

The control unit is a DSP. Note that the control signal generation processing 15 of FIG. 1 includes the processing of the speed calculation unit 65 and the movement control signal generation unit 66 of FIG. The optimum phase determination processing 16 in FIG. 1 is included in the processing of the edge interval determination unit 64 in FIG. Medium type determination processing 1 in FIG.
7 corresponds to the processing of the medium type determination unit 64 'in FIG.

The operation of the configuration shown in FIG. 6 will be described. DSP70
Controls each unit of the control unit 42. TES signal generated by the TES signal circuit and selected according to the MO mode or the CD mode (TES signal 1 or TES signal 2)
Are input from the input unit 60 to the TZC signal generation unit 61. The TZC signal generator 61 receives the input TES
A TZC signal is generated based on the signal. On the other hand, the seek direction determination unit 62 determines the moving direction of the optical pickup unit 56 in the seek control. The medium type determining unit 64 'determines the type of the medium of the optical disk set. Then, the medium type edge interval determination unit 64 determines the optimum edge of the TZC signal according to the type of medium and the seek direction, and determines the optical pickup unit 56 based on the edge interval of the TZC signal.
Is required to move between tracks. The speed calculation unit 65 calculates ΔΔ based on the time ΔT obtained by the edge interval determination unit 64 and the track pitch L of the set optical disk.
The moving speed of the light receiving unit is calculated based on T / L.

The movement control signal generator 66 generates a control signal for controlling the movement of the optical pickup 56. For example,
A difference between the target speed and the current speed is obtained, and a control signal for speed control is generated. The control signal is output from the output unit 67 to the optical pickup driving device. The optical pickup driving device 43 controls the optical pickup unit 56 according to the control signal.
Drive.

FIG. 7 shows an embodiment of the configuration of the TES signal circuit of the present invention. In FIG. 7, reference numeral 38 denotes a light receiving unit,
It has a split light receiver 80.

Reference numeral 40 denotes a TES signal circuit. 181 is M
A TES signal generation circuit for O, which generates a TES signal 1 by a push-pull method based on a quadrant signal.

Reference numeral 182 denotes a TES signal generation circuit for CD, which generates the TES signal 2 by the heterodyne method based on the quadrant signal. Reference numeral 183 denotes a multiplexer (MPX), which outputs a TES signal for MO (TES signal 1) or a TES signal for CD (TES signal) according to a switching signal.
The signal 2) is selected and output.

In the configuration shown in FIG. 7, the TES signal generating circuit 181 for the MO outputs the optical signals Ea and E
b, Ec, and Ed are input, and the difference (Ea + Ed) between two added signals obtained by adding the light receiving signals at the adjacent light receiving positions is obtained.
A TES1 signal is generated from (Eb + Ec).

The TES signal generation circuit for CD 182
Are the optical signals Ea, Eb, Ec, E
d is input, and two signals obtained by subtracting the light receiving signals at the adjacent light receiving positions, that is, the heterodyne signal (Ea + Ec)-(Eb + Ed) (Eb + Ed)-(Ea + Ec) are added to the sum of the four light receiving signals (Ea + Eb + Ec + E).
The TES2 signal is generated as a composite signal that is sampled and held alternately at each timing obtained by the zero cross detection in d).

The MPX (83) operates according to the switching signal
The TES signal 1 or the TES signal 2 is selected according to the medium of the optical disk set. That is, when the MO is set in the optical disk device, the TES signal 1 is selected, and when the CD is set in the optical disk device, the TES signal 2 is selected and output to the control unit.

[0072]

According to the present invention, in seek control of an optical disk apparatus capable of driving different types of media, the phase (edge) of a TZC signal that accurately reflects track information of each medium is detected, and the phase is detected. Since the optical pickup unit is controlled based on the control signal, a control signal with less error can be generated. Therefore, the performance of the optical disk device can be improved.

[Brief description of the drawings]

FIG. 1 is a diagram showing a basic configuration of the present invention.

FIG. 2 is an explanatory diagram of a TES signal of an MO.

FIG. 3 is an explanatory diagram of a TES signal of a CD.

FIG. 4 is an explanatory diagram of an optimal phase of a TZC signal.

FIG. 5 is a diagram showing an embodiment of the device configuration of the present invention.

FIG. 6 is an explanatory diagram of an embodiment of a control unit according to the present invention.

FIG. 7 is a diagram showing an embodiment of a TES signal circuit of the present invention.

FIG. 8 is an explanatory diagram of a conventional technique.

[Explanation of symbols]

 1: heterogeneous medium driving device 2: medium driving unit 3: moving unit driving unit 4: optical signal input unit 5: control device 6: TES signal generation unit 7: control means 10: TZC signal generation unit

Claims (4)

[Claims] 1. A TES signal generator for generating a tracking error signal for an optical disk, and a control for generating a zero-cross signal based on the tracking error signal in seek control and driving a moving body moving on the optical disk based on the zero-cross signal. Signal generating means for generating a zero-cross signal based on the tracking signal; determining a type of the optical disk medium set; and controlling the phase based on the phase A of the zero-cross signal. The optimum phase A for the optical disk medium A in which the control signal generated is optimum or the optimum phase B for the optical disk medium B in which the control signal generated based on the phase B of the zero cross signal is optimum is detected. When set, the control signal of the moving body drive unit based on the phase A And a control signal generation section for generating a control signal for the moving body drive section based on the phase B when the optical disk of the medium B is set. 2. The moving body is an optical pickup unit, and the control means determines a medium type of the optical disk medium and seeks the moving direction of the moving body in seek control of the optical pickup unit. A direction determining unit, an edge interval determining unit that determines an edge interval of an edge corresponding to an optimum phase of a zero cross signal according to a medium type, and calculating a moving speed of the optical pickup unit based on the edge interval and a track pitch of the medium. 2. The control device for an optical disk device according to claim 1, further comprising: a speed calculation unit; and a movement control signal generation unit that generates a movement control signal of the optical pickup unit based on a calculation result of the speed calculation unit. 3. The optical disk A of the medium A is a magneto-optical disk (MO), the optical disk of the medium B is a compact disk (CD), and the TES signal generation unit performs a push-pull method based on the optical signal divided into four. TES for MO
A TES signal generator for generating a signal and a TES for a CD based on the optical signal divided into four parts by a heterodyne method.
3. The control device for an optical disk device according to claim 1, further comprising a CD TES signal generation unit that generates a signal. 4. A method for controlling an optical disk device, comprising: generating a tracking error signal for an optical disk; generating a zero-cross signal based on the tracking signal; determining the type of the optical disk medium being set; The optimum phase A for the optical disk medium A in which the control signal generated is optimum or the optimum phase B for the optical disk medium B in which the control signal generated based on the phase B of the zero-cross signal is optimum is detected. Is set based on the phase A of the zero-cross signal, and a control signal for the moving body driver is generated based on the phase B of the zero-cross signal when the optical disk of the medium B is set. A control method for an optical disk device, comprising: generating a control signal for generating a control signal of (1).