WO2007077714A1

WO2007077714A1 - Servo control device, information reproducing device, information reproducing/recording device, servo control method, servo control program, and information reproducing medium where servo control program is recorded

Info

Publication number: WO2007077714A1
Application number: PCT/JP2006/324514
Authority: WO
Inventors: Takaaki Ujiie; Yoshimichi Nishio; Yoshihiro Hashizuka
Original assignee: Pioneer Corporation
Priority date: 2006-01-06
Filing date: 2006-12-08
Publication date: 2007-07-12
Also published as: JP2009064478A

Abstract

A servo control device for performing servo control to record information in an optical recording medium having a lot of information layers by enabling light to stably and quickly reach an desired layer, even if the types of the information layers are different, an information reproducing device, a servo control method, an servo control program, and an information recording medium where a servo control program is recorded are provided. The servo control device has a constitution in which when the types of layers of an information recording medium identified by identifying means are different from one another and when the focus position of light emitted from light-emitting means is moved across the information layers, control means controls the rotational speed of the information recording medium to the one of when the information recorded in the movement-destination information layer is reproduced by means of rotating mean and moves the focus positions to the movement-destination information layer by means of moving means.

Description

Specification

Servo control device, information reproducing device, information reproducing / recording device, servo control method, servo control program, and information recording medium recording servo control program

[0001] The present application relates to the field of servo control of an optical disc information reproducing / recording apparatus.

Background art

[0002] An information recording medium called a disk-shaped optical disc and an optical disc apparatus capable of recording / reproducing with respect to such an information recording medium are non-contact, have a large capacity, and can be accessed at high speed. It is a portable and low-cost medium. As a recording / playback device for various types of information, for example, a recording / playback device for digital audio signals and digital video signals, It is also widely used as an external storage device for computers.

[0003] On the other hand, optical discs, which are optical information recording media used in powerful devices, can be used in addition to conventional single-layer discs that have a large recording capacity. Various (multilayer) optical discs in which a plurality of information recording layers are formed in the rotational axis direction have been proposed or put into practical use. As an example of such a multi-layer optical disk, for example, in a read-only DVD 2-layer optical disk called DV D (Digital Versatile Disc) -DL (Dual layer), the multiple layers, layer 0 and layer (layer) Since the addresses are recorded in advance in both of the information recording layers of l, on the optical disk apparatus side that reproduces the information, it moves to another layer at any position in the radial direction of the disk between these multiple layers (focus) Jump), you can check the address in that layer.

[0004] For this reason, in the conventional optical disk apparatus, when control including a focus jump between these recording layers is performed, a focus jump is normally performed at the current address position, and then a search is made to the target address position. Was doing the operation.

[0005] Further, according to Patent Document 1 below, in a disk drive device that records or reproduces data on a signal recording surface having a plurality of layers, a signal is recorded between different signal recording surfaces (layers). When accessing, if the search is to the inner circumference, the rotation speed of the optical disk is accelerated, and if the search is to the outer circumference, the rotation speed of the optical disk is reduced.

Patent Document 1: Japanese Patent Laid-Open No. 10-143873

Disclosure of the invention

Problems to be solved by the invention

[0006] On the other hand, in the case of a multi-layer disc in which different types of optical discs are multi-layered, when searching to the inner circumference, the rotational speed of the optical disc is not necessarily accelerated but may be reduced. . In this case, the rotational speed of the accelerated optical disk must be decelerated, and more search time is required.

[0007] Further, in the case of a multi-layer disc in which different types of optical discs are multilayered, there is a case where the rotation speed of the optical disc is not necessarily reduced when searching to the outer periphery. In this case, the rotational speed of the decelerated optical disk has to be accelerated, and more search time is required.

[0008] Therefore, the present application has been made in view of the above inconveniences, and an example of the problem is that, in an optical recording medium having many information layers, the desired information can be quickly obtained even when the physical formats of the information layers are different. It is an object of the present invention to provide a servo control device, an optical disk reproducing device, a servo control method, a servo control program, and an information recording medium on which a servo control program is recorded.

Means for solving the problem

[0009] The servo control device according to claim 1 of the present invention is the servo control device for reproducing the information from an information recording medium having a plurality of information layers on which information to be reproduced is formed. Rotating means for rotating the recording medium, light emitting means for emitting light incident on the information recording medium, and light emitted from the light emitting means is condensed on the information layer and reflected from the information layer A light receiving means for receiving the received light, an optical signal generating means for generating a light electric signal reflected from the information layer and received by the light receiving means, and the electric signal generated by the electric signal generating means. A determining means for determining the type of the information layer, a moving means for moving a condensing position of the light emitted from the light emitting means from one information layer to another information layer, and A computing means for computing the number of rotations of the information recording medium when reproducing information recorded in the information layer on the basis of the electrical signal generated by the electrical signal generating means; When the converging position is moved using the moving means, the calculation means calculates the number of rotations of the information recording medium when reproducing the information recorded in the information layer of the movement destination, Control means for rotating the information recording medium by the rotating means based on the calculation result by the calculating means, and when the types of the plurality of information layers in one information recording medium determined by the determining means are different Then, when the condensing position of the light emitted from the light emitting means moves between the information layers of different types, the control means uses the rotating means to record the information recording medium. The number of rotations of the medium is controlled to the number of rotations of the information recording medium when reproducing information recorded on the information layer at the destination, and the position of the information layer at the destination is determined using the moving means. The condensing position is moved.

The servo control method according to claim 6 of the present invention is the servo control method for reproducing the information from the information recording medium having a plurality of information layers on which the information to be reproduced is formed. A rotating step for rotating; a light emitting step for emitting light incident on the information recording medium; and the light emitted in the light emitting step is condensed on the information layer and reflected from the information layer. A light receiving step for receiving light, an electrical signal generating step for generating an electrical signal from the light reflected from the information layer and received by the light receiving step, and generated for the electrical signal generating step. A discriminating step for discriminating the type of the information layer based on the electrical signal, and a condensing position of the light emitted in the light emitting step from one information layer to another information layer Travel distance and The number of rotations of the information recording medium when the information recorded in the information layer is reproduced is calculated based on the electric signal generated in the electric signal generating step. In the calculation step and the movement step, when the condensing position is moved, the rotation number of the information recording medium when reproducing the information recorded in the information layer of the movement destination is calculated in the calculation step. And a control step of rotating the information recording medium according to the calculation result in the calculation step, the rotation step, and the control step of rotating the information recording medium. A plurality of the information in the information recording medium When the type of the information layer is different, the condensing position of the light emitted in the light emission step moves between the information layers of different types, and in the control step, the rotation step! The number of rotations of the information recording medium is controlled to the number of rotations of the information recording medium when information recorded on the information layer at the movement destination is reproduced, and at the position of the information layer at the movement destination in the movement step It is characterized by moving the condensing position.

A servo control program according to claim 7 of the present invention includes a computer included in a servo control device for reproducing the information from an information recording medium having a plurality of information layers on which information to be reproduced is formed. Rotating means for rotating the information recording medium, light emitting means for emitting light incident on the information recording medium, and condensing the light emitted from the light emitting means on the information layer and from the information layer Light receiving means for receiving the reflected light, electric signal generating means for generating an electric signal from the light reflected from the information layer and received by the light receiving means, and the electric signal generated by the electric signal generating means And a moving means for moving the condensing position of the light emitted from the light emitting means from one information layer to the other information layer based on the information layer. A calculating means for calculating, based on the electric signal generated by the electric signal generating means, the number of rotations of the information recording medium when the information recorded in the information layer is reproduced in the information layer; When the converging position is moved using the moving means, the number of rotations of the information recording medium when reproducing the information recorded in the information layer at the movement destination is calculated by the calculating means. And a function as a control means for rotating the information recording medium by the rotating means based on a calculation result by the calculating means, and a plurality of types of the information layers in the one information recording medium determined by the determining means. In a different case, when the light collection position of the light emitted from the light emitting means moves between the different information layers, the control means is controlled by the rotating means. It functions to control the rotational speed of the information recording medium to the rotational speed of the information recording medium when reproducing the information recorded in the information layer of the moving destination, and uses the moving means to move the moving destination It is made to function so that the said condensing position may be moved to the position of the said information layer. Brief Description of Drawings

FIG. 1 is a block diagram showing a schematic configuration example of an optical disc playback apparatus according to an embodiment.

FIG. 2 is a diagram showing a positional relationship between a focus position of a pickup and an information layer of an optical disc according to the embodiment.

FIG. 3 is a flowchart showing the search control operation in the dual-layer optical disc of the embodiment.

Explanation of symbols

1 · · • Optical disc

2 ··· • Pickup

3 ··· • Motor section

4 · · · Driver section

5 ··· • Amplifier

6 ··· • Signal processor

7 · · · Digital-to-analog converter

8 ··· • Microcomputer

LB… Laser beam

BEST MODE FOR CARRYING OUT THE INVENTION

Next, an embodiment that is most suitable for the present application will be described with reference to the drawings.

[0015] In the following embodiments, when there are a plurality of information layers for writing information or reading information on an optical disc such as a DVD, the pickup is moved between different information layers. Thus, the servo control operation is described above.

[0016] It should be noted that a plurality of information layers present on one optical disc are different types of information layers or the same type of information layers.

(I) Overall configuration and operation

First, an overall configuration of an optical disk information reproducing apparatus including an optical disk servo control apparatus according to an embodiment will be described with reference to FIG.

FIG. 1 is a block diagram showing a schematic configuration example of an optical disc information recording / reproducing apparatus according to an embodiment. FIG.

As shown in FIG. 1, the laser beam LB emitted from the pickup 2 is reflected by the information layer of the optical disc 1, and the reflected laser beam LB is converted into information in the information layer of the optical disc 1. In response to the change, the change is converted into an electric signal Si in the pickup 2. Based on the converted electrical signal Si, the microcomputer section 8 analyzes servo information. Also, depending on the type of optical disc, the converted electrical signal Si is recorded on the optical disc 1 and includes the number of information layers and the servo information of the information layer. Is analyzed in the microcomputer section 8. The pickup 2 (or the objective lens inside the pickup 2) is moved to a desired position based on the number of information layers and the analysis result of the focus servo information.

Next, the detailed operation of the optical disc information recording / reproducing apparatus S according to the embodiment will be described with reference to FIG.

This optical disc information recording / reproducing apparatus S irradiates the information layer of the optical disc 1 with a laser beam LB, and converts the laser beam LB reflected on the optical disc 1 into an electric signal Si. Pickup 2 as means, electric signal generating means, and moving means, amplification section 5 for amplifying input electric signal Si and outputting amplified signal Sa, and signal processing for input amplified signal Sa The signal processing unit 6 outputs the digital video Z audio signal Sda and the signal Spm including information such as servo information, and outputs the driver signals Sdp and Sdm by processing the input control signal Smp. Digital video Z audio signal Sda and digital signal based on control signal Scd Digital video Z audio signal Sd a Digital-analog conversion to output analog video Z audio signal So A conversion unit 7 (hereinafter referred to as a DAC unit) and a determination means for performing calculation based on the signal Spm and outputting a control signal Scd for controlling the DAC unit 7 and a control signal Smp for controlling the pickup 2 and the motor unit 3 , Calculating means, control means, reproducing means, and recording information generating means 8 and amplifying the input motor driver signal Sdm and pickup driver signal Sdp to obtain motor control signal Sm and pickup control signal Sp Recorded on the optical disk 1, the driver section 4 to output, the motor section 3 as a rotating means for rotating the optical disk 1 based on the input motor control signal Sm, and the optical disk 1 It consists of an input unit 9 that allows the position from which information is to be read to be input from the outside.

[0021] The output signal So output from the DAC unit 7 is viewed by the user via a power amplifier (not shown) or the like, or a loudspeaker such as a speaker, such as a liquid crystal display device.

Next, each component will be specifically described.

The electric signal Si includes information recorded on the information layer of the optical disc 1 and servo information related to the condensing position of the laser beam LB.

[0024] For example, the electrical signal Si includes information for determining whether the pickup 2 is in an appropriate position for reading information in the information layer of the optical disc 1 (focus error signal information and tracking error). Error signal information such as signal information) and servo information such as linear velocity information for the pickup 2 to read out the information recorded in the information layer.

[0025] The amplification unit 5 receives an electric signal Si indicating information recorded on the optical disc 1 and servo information. The electric signal Si is amplified in the force amplifying unit 5 which is a weak signal, and is output as an amplified signal Sa that can be easily handled in the signal processing unit 6 in the subsequent stage.

[0026] The amplified signal Sa and the control signal Smp are input to the signal processing unit 6. The signal processing unit 6 performs arithmetic processing on various kinds of information included in the amplified signal Sa, and outputs a processing signal Spm including information such as the digital video Z audio signal Sda and servo information.

[0027] For example, the signal processing unit 6 generates a digital video Z audio signal Sda by performing a decoding process on the amplified signal Sa that represents the information encoded and recorded on the optical disc 1, and outputs it. To do. Based on the control signal Smp, the servo signal included in the amplified signal Sa is set to an appropriate amplification factor and the servo circuit is opened and closed.

[0028] Further, the signal processing unit 6 receives the motor driver signal Sdm and the pickup 2 (or the inside of the pickup 2) for rotating the motor unit 3 at a predetermined rotational speed from the input control signal Smp. The pickup driver signal Sdp, which is a signal for moving the objective lens), is generated and output to the driver unit 4. [0029] The driver unit 4 amplifies the input motor driver signal Sdm to a voltage necessary for driving the motor unit 3, and outputs a motor control signal Sm. The driver unit 4 amplifies the input pickup driver signal Sdp to a current necessary for driving the pickup 2 (or an objective lens inside the pickup) and outputs a force pickup control signal SP.

The motor unit 3 rotates the optical disc 1 based on the input motor control signal Sm.

[0031] The digital video Z audio signal Sda and the control signal Scd are input to the DAC unit 7.

The DAC unit 7 converts the digital video Z audio signal Sda into an analog signal from the digital signal, generates an analog video Z audio signal So, and outputs the analog video Z audio signal So based on the control signal Scd. .

For example, the control signal Scd is a signal for performing stop or start control of the output of the analog video Z audio signal So to be output from the DAC unit 7.

A processing signal Spm is input to the microcomputer unit 8.

[0034] As described above, the processing signal Spm includes information such as the digital video Z audio signal Sda and servo information.

[0035] Servo information includes information indicating the intensity of reflected light from the optical disc 1 for measuring the reflectance of the information layer of the optical disc 1, focus error signal information indicating the state of the focus search caused by movement of the pickup 2, Track cross signal information and tracking error signal information indicating the track search status, information indicating the number of information layers, information layer type and linear velocity recorded in the information layer, or reflectivity for each information layer This includes optical disk reflectivity information.

[0036] The information indicating the reflected light intensity includes, for example, an electric signal level corresponding to the reflected light intensity. The microcomputer unit 8 determines the amplification factor of the electric signals of the focus servo circuit and the track servo circuit, which are composed of the pickup 2, the amplification unit 5, the signal processing unit 6, and the driver unit 4, according to the information indicating the reflected light intensity. To decide. This amplification factor is determined for each information layer if the intensity of reflected light differs for each information layer. As described above, the microphone mouth computer unit 8 is used in the focus servo circuit and the track servo circuit. The signal amplification factor is changed by the light reflectance of the information layer where the laser beam LB is focused. A focus servo circuit and a track servo circuit with an appropriately set amplification factor can operate stably.

The focus error signal is information representing the positional relationship between the focal position of the light beam LB emitted from the pickup 2 and the direction orthogonal to the information layer of the optical disc 1. For example, when the focus error signal is expressed by the so-called push-pull method, the closer the focus error signal approaches zero, the closer the focus position of the light beam LB and the information layer of the optical disc 1 become, (Excluding optical and electrical offsets)

[0038] The track cross signal is based on track information such as a land track and a groove track provided on the optical disc 1 when the pickup 2 is moved in the radial direction of the optical disc 1 with the focus servo circuit closed. Signal that changes. The microcomputer 8 calculates the distance that the pickup 2 has moved in the radial direction by counting the number of zero crossings of the track cross signal.

The track error signal is information indicating the positional relationship between the focal position of the light beam LB emitted from the pickup 2 and the radial direction parallel to the information layer of the optical disk 1. For example, when the track error signal is represented by the so-called DPP (Differential Push Pull) method for DVD or the three-beam method for CD (Compact Disc), the closer the track error signal is to zero, the more the focus of the light beam LB becomes. This indicates that the position of the optical disk 1 and the information layer of the optical disk 1 are approaching each other (excluding optical and electrical system offsets).

[0040] The number of information layers recorded in the information layer is recorded in advance in each layer, and is recognized by reading the information at least once. Information representing the linear velocity is determined in advance for each physical media type. The microcomputer unit 8 is recorded on the information layer from the information layer of the optical disc 1, and when reading information and recording information on the information layer, while detecting the focus error signal and the tracking error signal, Pickup 2 or Pickup 2 Pickup to control the pick-up driver signal, which is a signal to move the objective lens inside the pickup 2 Drive control information, and information indicating that the focus servo circuit and track servo circuit are closed at the appropriate timing The servo opening / closing information is output. [0041] Further, in this embodiment, when the focus position of the focus is moved from one information layer to another information layer, information indicating that the focus servo circuit and the track servo circuit are opened is displayed as servo open / close information. Output as. That is, when the focal point of the laser beam LB is moved from one information layer to another information layer, the pickup is moved after opening the focus servo circuit and the track servo circuit. After that, in order to focus the laser beam LB on another information layer, the focus servo circuit is closed and then the track servo circuit is closed.

On the other hand, the control signal Smp output from the microcomputer unit 8 includes focus direction drive control information for driving the pickup 2 (or an objective lens in the pickup 2) in order to perform a focus search. The focus servo included in the signal processing unit 6 is used to focus on the desired information layer in the radial direction drive control information for driving the pickup 2 (or the objective lens in the pickup 2) in the radial direction of the optical disc 1. Amplification factor determination information for determining the amplification factor of the signal of the circuit and the track servo circuit, focus servo opening / closing information indicating that the focus servo circuit is opened and closed, and a track indicating that the track servo circuit is opened and closed Servo open / close information is included.

For example, the focus direction drive control information is information used to recognize the position of the information layer of the optical disc 1 in the focus direction (direction orthogonal to the information layer of the optical disc 1). By generating a pickup driver signal Sdp based on the focus direction drive control information, the focal position of the laser beam LB of the pickup 2 is brought close to and away from the information layer of the optical disc 1. Then, since the focus servo signal included in the electric signal Si obtained from the pickup 2 has a V, so-called S-characteristic, a focus search operation can be performed.

The track direction drive control information is information used for recognizing the position in the radial direction of the information layer of the optical disc 1 (parallel to the information layer of the optical disc 1 and in the radial direction of the optical disc 1). is there. By generating the pickup driver signal Sdp based on the radial direction drive control information, the focal position of the pickup 2 by the laser beam LB is moved in the information layer of the optical disc 1 in the radial direction of the optical disc 1. In this case, obtained from pickup 2 One period of the track error signal and the track cross signal included in the electric signal Si to be generated corresponds to the track pitch formed on the optical disc 1. Therefore, by counting the number of periods such as the track cross signal, the microcomputer unit 8 can recognize how many tracks the pickup 2 has moved in the radial direction of the optical disc 1.

The amplification factor determination information is information that determines the magnitude of an electric signal in the focus servo circuit and the track servo circuit configured by the pickup 2, the amplification unit 5, the signal processing unit 6, and the driver unit 4. Depending on the reflectivity of the information layer of the optical disc 1, the magnitude of the electric signal Si output from the pickup 2 differs. Therefore, the microcomputer unit 8 determines the amplification factors of the focus servo circuit and the track servo circuit based on the reflected light intensity of the information layer, which represents the reflectance of the information layer included in the electric signal Si.

[0046] The amplification factor determination information included in the control signal Smp corresponding to the amplification factor determined in the microcomputer unit 8 is used to determine the amplification factors of the focus servo circuit and the track servo circuit in the signal processing unit 6. To do. For example, by changing the resistance values of the amplifiers included in the focus servo circuit and the track servo circuit using an analog switch circuit, the amplification factors of the focus servo circuit and the track servo circuit can be changed and determined. Therefore, the amplification factor of the force servo circuit and the track servo circuit is set to be different for each information layer having a different reflectance.

[0047] The focus servo open / close information includes the force that opens the focus servo circuit configured by the pickup 2, the amplification unit 5, the signal processing unit 6, and the driver unit 4, or the light beam LB on the information layer. This information is used to determine whether to close the focus servo circuit when writing information and reading information from the information layer.

In the case of information for opening the focus servo circuit, the signal processing unit 6 sets, for example, an analog switch circuit included in the focus servo circuit to an open state in order to open the focus servo circuit. In the case of information for closing the focus servo circuit, the signal processing unit 6 sets, for example, an analog switch circuit included in the focus servo circuit to a closed state in order to close the focus servo circuit.

[0049] Track servo opening / closing information includes a pickup 2, an amplification unit 5, a signal processing unit 6, and a driver. Close the track servo circuit when performing the operation to write the information to the information layer using the optical beam LB and the operation to read the information from the information layer. This is information for determining whether to enter the state.

[0050] When the track servo opening / closing information is information for opening the track servo circuit, the signal processing unit 6 sets, for example, an analog switch circuit included in the track servo circuit to an open state in order to open the track servo circuit. . When the track servo open / close information is information for closing the track servo circuit, the signal processing unit 6 sets, for example, an analog switch circuit included in the track servo circuit to a closed state in order to close the track servo circuit.

[0051] When the microcomputer unit 8 writes information on the optical disc 1, the microcomputer unit 8 drives the signal processing unit 6, the amplification unit 5 and the pickup 2 and uses the laser beam LB to drive the optical disc. Write information to 1.

(II) Embodiment of the present application

Next, the present embodiment will be described with reference to FIG. 2 and FIG. In the present embodiment, the search control operation in the case where the optical disc 1 has two information layers is described.

FIG. 2 is a diagram showing the positional relationship between the double-layer optical disc 1, the pickup 2, and the focal point SO of the laser beam LB. FIG. 3 is a flowchart showing the search control operation in the double-layer optical disc.

Hereinafter, the search control operation will be described with reference to FIG.

An optical disc 1 shown in FIG. 2 is a schematic cross-sectional view showing a cross section of the optical disc 1 in which the vicinity of the center position of the optical disc 1 is omitted.

The optical disc 1 has two information layers, an information layer LO and an information layer L1. Information layer LO

It is based on the physical format of the CD. On the other hand, the information layer L1 is formed based on the physical format of the DVD!

[0056] A laser beam LB emitted from a semiconductor laser (not shown) provided in the pickup 2 is condensed by an objective lens (not shown) provided in the pickup 2, and is positioned at a position SO. In focus. [0057] The position SO is a focal point in the information layer LO on which the pickup 2 is focused in order to read information recorded in the information layer LO.

In order to read the information recorded at the position S1 in the information layer L1, it is necessary to move the pickup 2 so that the position S1 is focused.

[0059] In this case, the focus of the pickup 2 may move to the position S1 via the path K12 and then move to the position S1 via the path K12.

[0060] The focus of the pickup 2 may move to the position S1 via the path K22 after moving to the position SK2 via the path K21.

[0061] The position S1 is located on the outer peripheral side of the optical disc 1 with respect to the position SO. Therefore, if the information layer LO and the information layer L1 are in the same optical disk physical format and the servo control is not performed with a constant angular velocity (for example, when the linear velocity is constant), the rotation of the optical disc 1 at the position S1 is performed. The number is slower than the rotational speed of the optical disc 1 at the position SO.

However, when the information layer L0 in the present embodiment is a CD physical format, the linear velocity, which is the relative velocity between the pickup 2 and the optical disc 1, is from 1.2 mZ seconds to 1.4 mZ seconds. When the information on the inner circumference (radius position 25 mm from the center of the optical disk 1) is read by the pickup 2, the rotation speed of the optical disk is 459 rpm (revolutions per minute) to 535 rpm.

[0063] On the other hand, when the information layer L1 is a DVD physical format, the linear velocity is about 3.49 mZ seconds, so the information on the outer periphery (radius position 58 mm from the center of the optical disc 1) is read by the pickup 2 In this case, the rotation speed of the optical disk 1 is about 575 rpm (revolutions per minute).

[0064] Therefore, the rotational speed of the optical disc 1 at the position S1 on the outer peripheral side is larger than the rotational speed of the optical disc 1 at the position SO.

[0065] The relationship between the linear velocity L (mZ seconds), the radial position r (mm) of the central force of the optical disc 1, and the rotational speed M (rpm) of the optical disc 1 is expressed by equation (1). .

[0066] [Equation 1]

L / (2 X π X (r / 1000)) X 60 = M formula (1)

In this embodiment, when the focus position of the pickup 2 is at the position SO, the information layer L When trying to read information at position SI of 1, the optical disc information recording / reproducing apparatus s operates as follows.

[0067] After reading the information on the position SO in the information layer LO, the microcomputer unit 8 receives an instruction to read the information on the position S1 in the information layer L1.

This command may be recorded in the information at the position SO of the information layer LO and may be received from the input unit 9 by the microphone computer unit 8. The input unit 9 may be a switch of the optical disc information recording / reproducing apparatus S or may be an external information device.

[0069] Then, the microcomputer unit 8 calculates the number of rotations of the optical disc 1 at the position S1 necessary for reading the information recorded at the position S1 in the information layer L1.

[0070] The radial position of the position S1 is calculated by the microcomputer unit 8 performing an operation based on the physical format type of the information layer L1 of the optical disc 1 and the address information of the position S1.

[0071] The physical format type of the information layer L1 of the optical disc 1 is recorded in the control area of the microcomputer unit 8 force optical disc 1 and is recognized in advance using the information force pickup 2. Alternatively, information indicating the physical format type of the information layer L1 of the optical disc 1 is input from the input unit 9, and is recognized by the microcomputer unit 8.

[0072] Further, the address information of the position S1 is recognized by the microcomputer unit 8 from information recorded at the position S1 in the information layer L1 or a command received by the microcomputer unit 8 from the outside.

[0073] For example, if the position S1 is a radial position of 58 mm and the information layer L1 is a DVD physical format, the linear velocity is about 3.49 mZ seconds. The rotation speed of disk 1 is about 575 rpm. The microcomputer section 8 calculates this rotational speed of 575 rpm based on equation (1).

Then, the microcomputer unit 8 outputs a control signal Smp to the signal processing unit 6 so as to open the focus servo circuit and the track servo circuit (open state).

Then, the microcomputer unit 8 outputs a control signal Smp, which is information indicating that the rotation speed of the motor unit 3 is about 575 rpm, to the signal processing unit 6. The signal processing unit 6 to which the control signal Smp has been input sends the motor driver signal so that the rotational speed of the motor unit 3 is about 575 rpm. The Sdm is output to the driver unit 4. The driver unit 4 outputs a motor control signal Sdm to the motor unit 3 so that the rotational speed of the motor unit 3 is about 575 rpm. The motor unit 3 sets the rotational speed of the optical disc 1 to about 575 rpm.

[0076] It should be noted that the rotational speed of the optical disk 1 when the focus of the pickup 2 is at the position SO before the rotational speed of the optical disk 1 is changed to about 575 rpm is approximately when the position SO is a radial position of 25 mm. 495rpm force is about 535rpm.

[0077] Then, when the rotational speed of the optical disc 1 is changed to about 575 rpm, the microcomputer unit 8 causes the path Kl 1 via the focal position force position SK1 of the light beam LB emitted from the pickup 2. The pickup driver signal Sdp is output to the driver unit 4 via the signal processing unit 6 so as to reach the position S 1 through the path K12.

[0078] On the path Kl 1, the focus position of the light beam LB emitted from the pickup 2 performs a focus search operation and then performs a focus jump from the information layer L0 to the information layer L1. In this case, the microcomputer unit 8 controls to change the wavelength of the laser beam LB emitted from the semiconductor laser in the pickup 2 in the vicinity of the focal position force position SO of the light beam LB emitted from the pickup 2. .

[0079] Specifically, the wavelength emitted by the semiconductor laser power in the information layer L0 in the CD format is about 780 nm. The wavelength emitted by the semiconductor laser in the information layer L1 in the DVD format is about 650 nm. is there. This wavelength change of the semiconductor laser is performed at the position SO before the focus jump is performed by the pickup 2 under the control of the microcomputer unit 8.

In addition, the microcomputer unit 8 has a signal processing unit 6 so that the light beam LB emitted from the pickup 2 reaches the position S 1 through the path K21 and the path K22 via the focal point position SK2 of the light beam LB. The pickup driver signal Sdp is output to the driver unit 4 via.

[0081] In the path K22, the focus position of the light beam LB emitted from the pickup 2 performs a focus search operation and then performs a focus jump from the information layer L0 to the information layer L1. In this case, in the vicinity of the focal position force position SK2 of the light beam LB emitted from the pickup 2, the microcomputer unit 8 is connected to the semiconductor laser in the pickup 2. Control to change the wavelength of emitted laser beam LB.

[0082] Specifically, the wavelength at which the semiconductor laser power is also emitted in the information layer LO is about 780 nm, whereas the wavelength at which the semiconductor laser power is also emitted in the information layer L1 is about 650 nm. This wavelength change of the semiconductor laser is performed by the pickup 2 based on the control of the microcomputer unit 8 at the position SK2 before the focus jump.

[0083] This will be described in more detail below.

[0084] Since the information layer LO is a CD physical format, the wavelength of the laser beam for reading the information recorded in the information layer LO is about 780 nm.

[0085] On the other hand, since the information layer L1 is a DVD physical format, the wavelength of the laser beam LB for reading information recorded in the information layer L1 is about 650 nm.

Accordingly, the microcomputer unit 8 has a laser beam L emitted from the pickup 2.

The pickup driver signal Sdp is output to the driver unit 4 via the signal processing unit 6 so that the wavelength of B is changed to about 650 nm as well as about 780 nm force.

[0087] After the wavelength of the laser beam LB emitted from the pickup 2 changes to about 650 nm, the microcontroller unit 8 outputs a control signal Smp to the signal processing unit 6 so as to close the focus servo circuit.

[0088] Then, the signal processing unit 6 performs the focus search operation on the information layer L1.

Close the focus servo circuit.

Next, the microcomputer unit 8 sends a control signal Smp to the signal processing unit 6 so as to close the track servo circuit in order to accurately move the focus of the laser beam LB emitted from the pickup 2 to the position S1. Is output.

[0090] When the track servo circuit is closed, the focus of the laser beam LB traces the center of a land track or the center of a groove track in the information layer of the optical disc 1.

Then, the information recorded in the information layer L1 is incident on the pickup 2 as reflected light of the laser beam LB, and is input to the microcomputer unit 8 via the amplification unit 5 and the signal processing unit 6. .

[0092] The microcomputer unit 8 reflects the reflected light of the laser beam LB reflected from the information layer L1. Based on the information layer LI information is analyzed. Information in the information layer L1 includes a track number (track address). The microcomputer unit 8 can recognize how many tracks the position S1 and the focal point of the laser beam LB deviate by recognizing the track address (track error recognition).

[0093] If the focal point of the laser beam LB can be moved by the number of tracks in which a track error has occurred by moving the objective lens in the pickup 2, the microcomputer unit 8 includes the signal processing unit 6 and the driver. The control signal Smp is output via the unit 4 so that the objective lens jumps by the track error in the radial direction of the optical disc 1 (fine search).

[0094] After the objective lens performs track jump, the microcomputer unit 8 analyzes the track address included in the information layer L1 again based on the reflected light of the laser beam LB reflected from the information layer L1.

[0095] As a result of the analysis, if the focus of the laser beam LB is at the position S1, the microcomputer unit 8 picks up the information recorded in the information layer L1 at the position S1, the pickup 2 and the amplification unit 5 Analysis is performed via the signal processing unit 6.

In the above-described embodiment, when the motor unit 3 matches the rotation speed at the position S1 that is the search target position, the pickup 2 is moved, and the frequency of the laser semiconductor in the pickup 2 is set. However, the present embodiment is not limited to this.

[0097] For example, after switching to the laser beam LB having a wavelength corresponding to the physical format of the information layer L1 at the search target position S1, the motor unit 3 adjusts the rotation speed to the rotation speed at the position S1 that is the search target position. An operation can also be performed.

[0098] When the focal point of the laser beam LB moves to the position SK1 via the path K11, the microcomputer unit 8 opens the track servo circuit and moves the pickup 2 from the position SK1 to the search target. Move to near position S1. Then, the microcomputer unit 8 closes the tracking servo circuit. Then, the microcomputer unit 8 performs the above-described fine search and moves the focal point of the laser beam LB to the search target position S1.

Next, the operation of the present embodiment will be described using the flowchart of the present embodiment in FIG. [0100] The operation of each step will be described.

[0101] In step S1, the microcomputer unit 8 determines whether or not a jump request to another information layer has been received from the information layer of the optical disc 1 where the focal point of the laser beam LB is located.

[0102] If the microcomputer unit 8 has not received a jump request, step S1 is repeated. If the microcomputer unit 8 has received the jump request, the process proceeds to step S2.

[0103] In step S2, the microcomputer section 8 determines whether or not the information layer media type (physical format) for which a jump request has been made is known.

[0104] Microcomputer unit 8 If the type of media in the information layer for which a jump request has been made is not known, the process proceeds to step S17. Microcomputer part 8 If the type of media in the information layer for which a jump request has been made, proceed to step S3.

[0105] In step S3, whether or not the rotation speed (number of rotations) of the jump destination information layer differs from the rotation speed of the information layer of the optical disc 1 where the focal point of the laser beam LB is located Judging.

[0106] If the microcomputer unit 8 determines that the rotation speeds are the same, the process proceeds to step S4. If the microcomputer unit 8 determines that the rotation speed is different, the step

Proceed to S17.

[0107] In step S4, the microcomputer unit 8 calculates the distance in the radial direction from the rotation center position of the optical disc 1 at the search target position. Then go to step S5.

In step S5, from the media type of the search target information layer acquired in step S2 and the radial distance of the search target position acquired in step S4, the number of rotations of the optical disc 1 at the search target position is calculated by the microcomputer. Part 8 calculates. Then go to step S6.

[0109] In step S6, the microcomputer unit 8 controls the motor unit 3 so as to rotate the optical disc 1 at the number of rotations calculated in step S5. Next, the process proceeds to step S7, and the subsequent processing is performed together with the change to the calculated rotational speed.

[0110] In step S7, the microcomputer unit 7 performs a predetermined search. Determine whether the method is search method 1 or search method 2. The search method is stored in advance in a memory (not shown) of the microcomputer unit 8. If the search method is 2, go to step S14. If the search method is 21, proceed to step S8.

[0111] In step S8, the microcomputer unit 8 moves the focal position of the laser beam LB to a radius position where the search target position is located. Next, the process proceeds to step S9.

In step S 9, the microcomputer unit 8 drives a laser semiconductor having a laser wavelength corresponding to the information layer at the search target position, and changes the wavelength of the laser beam LB emitted from the pickup 2. Next, the process proceeds to step S10.

In step S10, the microcomputer unit 8 performs a focus search operation on the information layer at the search target position, and closes the focus servo circuit. Then go to step S11.

[0114] In step S11, the microcomputer unit 8 closes the track servo circuit. Then go to step S12.

[0115] In step S12, the microcomputer unit 8 picks up the ID (Identification) information including the track address and the like recorded in the information layer of the search target where the focal point of the laser beam LB is located, the pickup 2 and the amplification unit 5 And reading and analyzing via the signal processing unit 6. 〖こ Step S 13 〖こ itmu.

[0116] In step S13, the microcomputer unit 8 records the data in the information layer of the search target where the focal point of the laser beam LB is located. If the track address differs from the track address of the search target position, the microcomputer 8 To move the focus of the laser beam LB to the search target position.

Next, search method 2 will be described.

[0118] In search method 2, step S14 force is also described in step S16.

In step S14, the microcomputer unit 8 drives the laser semiconductor having the laser wavelength corresponding to the information layer at the search target position, and changes the wavelength of the laser beam LB emitted from the pickup 2. Next, the process proceeds to step S15.

[0120] In step S15, the microcomputer unit 8 sets the information layer at the search target position. Is subjected to a focus search operation to close the focus servo circuit. Then go to step S16.

[0121] In step S16, the microcomputer unit 8 moves the focal position of the laser beam LB to the radius position where the search target position is, and proceeds to step S11.

[0122] In step S17, a search that has been performed conventionally is performed. That is, when the search target position is on the inner periphery, the rotation speed of the optical disc 1 is increased, and when the search target position is on the outer periphery, the search operation is performed to decrease the rotation speed of the optical disc 1.

[0123] In the present embodiment, the force of using two recording / reproducing layers is not limited to this, and the present invention can also be applied to a case where there are three or more recording / reproducing layers.

[0124] In addition, the recording / playback layer is DVD-ROM (Read Only Memory), DVD-R (recordable), DVD-RW (Rewritable) DVD + RW DVD-RAM (Random Access memory), CD-ROM CD-R It is not limited to CD-RW, CD—DA (Digital Audio), BD (Blu-ray Disc), HD DVD (High-Definition DVD), etc., and any optical disk medium can be used.

[0125] The program corresponding to the flowchart of FIG. 3 is recorded in advance on a flexible disk or in advance via a network such as the Internet, and is read and executed by a general-purpose microcomputer or the like. By doing so, it is possible to make the general-purpose microcomputer or the like function as the CPU according to the embodiment.

[0126] As described above, according to the configuration of the servo control device described in the present embodiment, even when there are a plurality of different types of information layers on one optical disc, If the rotational speed of the optical disk can be recognized, the optical disk is rotated to the rotational speed at the target information layer position, and the focus position of the pickup is moved to the target information layer position. Can be made.

[0127] Since normal servo control can be quickly applied to the target information layer, the time required to read the information recorded in the target information layer can be shortened. It is out.

[0128] In other words, the method of moving the pickup is reinforced by controlling the rotational speed of the optical disc as in the prior art. If you want to read the information recorded in the target information layer by applying servo control after moving the focus position of the pickup to the target information layer position Compared to, the search time can be shortened.

[0129] For example, when the wavelengths of light to be irradiated are different between the information layers, in the conventional technology, the servo control is not applied after the focus position of the pickup is moved to the target information layer position. In addition, the servo information related to the target information layer may be moved to a part where it is recorded, and the servo information may be read out. It takes time until normal servo control is performed.

[0130] In addition, when moving the focus position of the pickup from the information layer on the inner periphery to the information layer on the outer periphery, conventionally, the rotation speed of the optical disk is decreased and the information layer on the outer periphery is changed to V. Then, do the servo control!

[0131] However, in this case, when the rotational speed of the optical disk must be increased in order to read the information recorded in the information layers with different outer circumferences, the conventional servo control device performs normal servo control. In order to fail and fail, it took time to perform normal servo control again. In addition, since the pick-up moves and the rotational speed of the optical disc must be decreased and then increased again, it takes time to reach the target rotational speed.

[0132] Further, when moving the focus position of the pickup from the outer information layer to the different information layer on the inner periphery, conventionally, by increasing the rotational speed of the optical disc, the information layer on the inner periphery is different. And apply servo control.

[0133] However, in this case, in order to read out information recorded in different information layers on the inner circumference, the rotational speed of the optical disk must be reduced. In this case, the conventional servo control device is normal. Since servo control could not be applied and failed, it took time to perform normal servo control again. In addition, since the pick-up moves and the rotation speed of the optical disk must be increased and then the rotation speed must be decreased again, it takes time to reach the target rotation speed.

[0134] Also, according to the configuration of the servo control device described in the present embodiment, even when there are a plurality of different types of information layers on one optical disk, the optical disk is rotated for each information layer. If the rotation number can be recognized by force, the optical disk can be rotated to the rotation speed at the target information layer position and focused on the target information layer.

[0135] Since the focus position of the pickup can be moved to the target position in the target information layer and normal servo control can be quickly applied, the information recorded in the target information layer can be read out. Time can be shortened.

[0136] The present invention is not limited to the above embodiment. The above embodiment is an exemplification, and the present invention has the same configuration as that of the technical idea described in the claims of the present invention, and any device that exhibits the same function and effect is the present embodiment. It is included in the technical scope of the invention.

[0137] Further, the entire disclosure of the Japanese patent application (No. 2006-001848) including the specification, claims, drawings and abstract filed on January 6, 2006 is referred to in its entirety. To be incorporated here.

Claims

The scope of the claims

[1] In a servo control device for reproducing the information from an information recording medium having a plurality of information layers on which information to be reproduced is formed, rotating means for rotating the information recording medium;

Light emitting means for emitting light incident on the information recording medium;

A light receiving means for condensing the light emitted from the light emitting means on the information layer and receiving the light reflected from the information layer;

An electric signal generating means for generating an electric signal from the light reflected from the information layer and received by the light receiving means;

Determining means for determining the type of the information layer based on the electrical signal generated by the electrical signal generating means;

Moving means for moving the condensing position of the light emitted from the light emitting means from one information layer to another information layer;

Calculation means for calculating the number of rotations of the information recording medium when reproducing information recorded on the information layer based on the electric signal generated by the electric signal generation means. When,

When the converging position is moved using the moving means, the number of rotations of the information recording medium when reproducing the information recorded in the information layer at the movement destination is calculated by the calculating means, Control means for rotating the information recording medium by the rotating means based on a calculation result by the calculating means,

In the case where the types of the plurality of information layers in the one information recording medium determined by the determination unit are different, the condensing position of the light emitted from the light emitting unit is different in the information layer. When moving the information recording medium, the control means controls the rotation speed of the information recording medium by the rotation means to the rotation speed of the information recording medium when reproducing the information recorded in the information layer of the movement destination. In addition, the servo control apparatus is characterized in that the converging position is moved to the position of the information layer of the moving destination using the moving means.

[2] In the focus control device according to claim 1, The control means controls the number of rotations of the information recording medium by the rotation means to the number of rotations of the information recording medium when reproducing information recorded in the information layer as a movement destination. After moving the condensing position in the parallel direction to the vicinity of the transfer destination, the light emitting step force is used to move the condensing position of the emitted light to the information layer at the destination using the moving means. A servo control device characterized by being moved.

[3] In the focus control device according to claim 1,

The control means controls the number of rotations of the information recording medium by the rotation means to the number of rotations of the information recording medium when reproducing information recorded in the information layer of the movement destination. After moving the light condensing position of the light emitted from the light emitting means to the information layer using the moving means, the light converging position is moved to the vicinity of the transfer destination in a direction parallel to the information layer. Servo control device characterized by moving.

[4] The servo control device according to any one of claims 1 to 3,

Based on the electric signal generated by the electric signal generating means, reproducing means for reproducing audio information or video information recorded in the information layer;

An information reproducing apparatus comprising:

[5] The information reproducing apparatus according to claim 4,

Recording information generating means for generating recording information to be recorded on the information layer, and the electric signal generating means generates an electric signal from the light reflected from the information layer and received by the light receiving means. An information reproduction recording apparatus for driving the light emitting means based on the recording information generated by the recording information generating means.

[6] According to a servo control method for reproducing the information from an information recording medium having a plurality of information layers on which information to be reproduced is formed, a rotation step of rotating the information recording medium;

A light emitting step for emitting light incident on the information recording medium;

The light emitted in the light emitting step is condensed on the information layer, and the information is A light receiving step for receiving light reflected from the information layer;

An electric signal generating step for generating an electric signal from the light reflected from the information layer and received in the light receiving step;

A discriminating step for discriminating the type of the information layer based on the electric signal generated in the electric signal generating step;

A moving step of moving a condensing position of light emitted in the light emitting step from one information layer to another information layer;

A calculation step for calculating the number of rotations of the information recording medium when reproducing the information recorded in the information layer based on the electric signal generated in the electric signal generation step. When,

When moving the condensing position in the moving step, the number of rotations of the information recording medium when reproducing the information recorded in the information layer of the moving destination is calculated in the calculation step. And a control step of rotating the information recording medium in the rotation step based on the calculation result in the calculation step.

When the types of the plurality of information layers in the one information recording medium determined in the determination step are different, the condensing position of the light emitted in the light emission step moves between the information layers of different types. In the control step, the rotational speed of the information recording medium is controlled to the rotational speed of the information recording medium when reproducing the information recorded in the information layer of the movement destination. In the moving step, the converging position is moved to the position of the information layer that is the moving destination.

A computer included in a servo control device for reproducing the information from an information recording medium having a plurality of information layers on which information to be reproduced is formed;

Rotating means for rotating the information recording medium,

An electrical signal is generated from the light reflected from the information layer and received by the light receiving means. Electrical signal generating means,

Discrimination means for discriminating the type of the information layer based on the electrical signal generated by the electrical signal generation means;

Moving means for moving a light collection position of light emitted from the light emitting means from one information layer to another information layer;

A calculating means for calculating the number of rotations of the information recording medium when reproducing the information recorded in the information layer based on the electric signal generated by the electric signal generating means;

When the converging position is moved using the moving means, the number of rotations of the information recording medium when reproducing the information recorded in the information layer at the movement destination is calculated by the calculating means, Based on the calculation result by the calculation means, the rotation means functions as a control means for rotating the information recording medium,

In the case where the types of the plurality of information layers in the one information recording medium determined by the determination unit are different, the condensing position of the light emitted from the light emitting unit is different in the information layer. When the information recording medium is moved, the control means controls the rotation speed of the information recording medium to the rotation speed of the information recording medium when the information recorded in the information layer of the movement destination is reproduced by the rotating means. And a servo control program for causing the condensing position to move to the position of the information layer at the destination using the moving means.

8. A recording medium, wherein the servo control program according to claim 7 is recorded in a computer in a readable manner.