JP2006269024A - Optical disk device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical disk device in which a tilt of a rotary shaft of an optical disk turntable can be adjusted with a less number of components. <P>SOLUTION: A motor mounting plate 114 is fixed by fastening screws and bosses 122 across a chassis 115 through compression springs. Also, the motor mounting plate is so structured that a single adjusting screw 100 can be screwed in from outside. With this structure, stress is applied to the motor mounting plate 114 by screwing in the adjusting screw 100. Thus, a tilt of the motor mounting plate 114 varies and the rotary shaft of a spindle motor is tilted. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an optical disc apparatus capable of recording or reading an optical disc such as a DVD (Digital Versatile Disc), and more particularly to an adjustment mechanism for adjusting a tilt of a pickup with respect to the optical disc.

  2. Description of the Related Art Conventionally, skew adjustment for adjusting a skew angle of an optical pickup with respect to an optical disk has been performed in a manufacturing process of an optical disk drive device. In this skew adjustment, when the optical pickup irradiates the optical disk with laser light, if the optical disk and the optical axis of the optical pickup are not orthogonal to each other, coma aberration occurs on the disk surface, making it impossible to focus on the pit of the optical disk. This is performed to prevent the data from being reproduced accurately.

  The skew adjustment will be described. The reflected light of the optical disc is detected by the optical system while changing the skew angle of the optical pickup with respect to the optical disc, and the jitter value is measured by the jitter measuring unit that measures the jitter. Then, the skew versus jitter characteristic is obtained, and the skew angle corresponding to the best jitter point is set as the adjustment target value.

For example, Patent Documents 1 to 3 disclose a method for adjusting various skew angles.
JP 2001-209947 A JP 2003-85803 A JP 2004-87031 A

  However, the methods disclosed in Patent Documents 1 and 2 disclose a method of adjusting the skew angle of the optical pickup with respect to the optical disc by adjusting the optical pickup side.

  In this respect, the skew angle can be adjusted not only by the optical pickup side but also by adjusting the inclination of the rotation axis of the rotary table of the optical disk.

  Patent Document 3 discloses a method of adjusting the rotation axis of the rotary table. Specifically, the inclination of the rotary shaft is adjusted by adjusting the height of the member that supports the motor that rotates the rotary table. ing.

  However, in Patent Document 3, fine adjustment is performed by adjusting the amount of screwing using a plurality of screws, and the number of parts is large. Moreover, when adjusting the height of the member that supports the motor using a plurality of screws, there is a possibility that the member is likely to be deformed because there are a plurality of portions where the screw stress is applied to the member.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide an optical disc apparatus capable of adjusting the inclination of the rotation axis of the rotary table of the optical disc with a small number of parts.

  An optical disc apparatus according to the present invention includes a disc table that holds an optical disc, a spindle motor that rotationally drives the disc table, a motor attachment plate that attaches the spindle motor, a support member that supports the motor attachment plate, and a support member. The chassis to which the motor mounting plate is fixed, the optical pickup that reads and writes the signal recorded on the optical disc by the light beam, and the angle at which the optical beam emitted from the optical pickup is applied to the optical disc is adjusted. An adjustment unit, a jitter measurement unit that measures a jitter value based on a signal output from the optical pickup, and a control unit that controls the entire apparatus. The adjusting means includes a screw portion that comes into contact with a predetermined position of the motor mounting plate by external twisting. The control means rotates the spindle motor to rotationally drive the disk table, reads the signal recorded by the optical pickup, and measures the jitter value by the jitter measuring means based on the read signal. Based on the measurement result of the jitter value from the jitter measuring means, the angle of the rotation shaft of the spindle motor is adjusted by pressing the motor mounting plate by twisting the screw portion. The optical pickup is executed near the middle circumference between the inner circumference and the outer circumference of the optical disc. The support member includes a spring. The motor mounting plate is coupled and fixed to the chassis via a spring.

  An optical disc apparatus according to the present invention includes a disc table that holds an optical disc, a spindle motor that rotationally drives the disc table, a motor attachment plate that attaches the spindle motor, a support member that supports the motor attachment plate, and a support member. The chassis to which the motor mounting plate is fixed, the optical pickup that reads and writes the signal recorded on the optical disc by the light beam, and the angle at which the optical beam emitted from the optical pickup is applied to the optical disc is adjusted. An adjustment unit, a jitter measurement unit that measures a jitter value based on a signal output from the optical pickup, and a control unit that controls the entire apparatus. The adjusting means includes a screw portion that comes into contact with a predetermined position of the motor mounting plate by external twisting. The control means rotates the spindle motor to rotationally drive the disk table, reads the signal recorded by the optical pickup, and measures the jitter value by the jitter measuring means based on the read signal. Based on the measurement result of the jitter value from the jitter measuring means, the angle of the rotation shaft of the spindle motor is adjusted by pressing the motor mounting plate by twisting the screw portion.

  Preferably, the optical pickup is executed near the middle circumference between the inner circumference and the outer circumference of the optical disc.

  Preferably, the support member includes a spring. The motor mounting plate is coupled and fixed to the chassis via a spring.

  The optical disc apparatus according to the present invention includes an adjusting unit that adjusts an angle at which the light beam emitted from the optical pickup is applied to the optical disc, and the adjusting unit is a predetermined one of the motor mounting plate by twisting from outside. Includes a threaded portion that contacts the point. Therefore, since the adjustment can be performed with a simple configuration, an optical disc apparatus with low cost can be provided.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals, and description thereof will not be repeated.

  FIG. 1 is a schematic block diagram of an optical disc apparatus according to an embodiment of the present invention.

  Referring to FIG. 1, an optical disc apparatus 1 records and / or reproduces information such as music and video on an optical disc 70 on which concentric or spiral information recording tracks such as CDs and DVDs are formed. .

  The optical disk apparatus 1 includes a disk insertion detection unit 2, a spindle motor 3, an optical pickup 4, a movement motor 5, a laser drive unit 6, a signal processing unit 7, a data slice signal generation unit 8, and a servo control unit. (Focusing control unit, tracking control unit) 9. Further, the optical disc apparatus 1 includes a video / audio signal input / output unit 10, a remote controller 11, a remote control receiving unit 12, a display unit 13, a jitter measuring unit 15, and a control unit 20 for controlling the above-described units. Yes.

  The optical pickup 4, the signal processing unit 7, the data slice signal generation unit 8, and the servo control unit 9 constitute an information reading unit.

  The disc insertion detection unit 2 detects that the optical disc 70 has been inserted from a disc insertion unit (not shown), and inputs the signal to the control unit 20. The inserted optical disk 70 is mounted on the spindle motor 3. The spindle motor 3 is driven to rotate in accordance with an instruction from the control unit 20 and controls the mounted optical disk 70 to rotate at a predetermined speed.

  The optical pickup 4 irradiates light for recording and / or reproducing information on the optical disc 70, receives reflected light from the optical disc 70, converts it into an electrical signal, and outputs it to the control unit 20. Is moved in the radial direction on the optical disk 70 by the moving motor 5 composed of a linear motor.

  The optical pickup 4 condenses and irradiates the light emitted from the semiconductor laser 41 onto the optical disc 70 via the collimating lens 42, the beam splitter 43, and the objective lens 44. The reflected light from the optical disk 70 is received by the photodetector 46 through the objective lens 44, the beam splitter 43, and the condenser lens 45.

  The light emission of the semiconductor laser 41 is controlled by the laser driving unit 6 that operates in response to an instruction from the control unit 20. The light detector 46 includes a divided photodiode that divides the light receiving surface into a plurality of regions and outputs an electric signal corresponding to the light reception intensity for each light receiving surface. The output signal from the light detector 46 is a signal process. Input to part 7.

  The objective lens 44 is held by a lens holder 47, and the lens holder 47 is provided with a focusing coil 48 and a tracking coil 49. The focusing coil 48 moves the objective lens 44 in a direction perpendicular to the disk surface of the optical disk 70 by a magnetic action with a magnet (not shown). Similarly, the tracking coil 49 moves the objective lens 44 in a direction perpendicular to the recording track of the optical disc 70 in parallel with the disc surface of the optical disc 70.

  The signal processing unit 7 generates an RF signal (reflection intensity) based on the output signal from the light detector 46 and outputs it to the data slice signal generation unit 8. The data slice signal generation unit 8 generates a data slice signal obtained by binarizing the RF signal and inputs the data slice signal to the control unit 20. The control unit 20 detects pits formed on the optical disc 70 based on the data slice signal.

  Further, the signal processing unit 7 generates a focus error signal and a track error signal based on the output signal from the light detector 46 and outputs the focus error signal and the track error signal to the servo control unit 9. The focus error signal is a signal corresponding to the amount of deviation of the condensing point of the light irradiated to the optical disc 70 through the objective lens 44 from the surface of the optical disc 70, and the track error signal is the deviation of the condensing point from the recording track. It is a signal corresponding to the quantity.

  The servo controller 9 controls the current supply to the focusing coil 48 and the tracking coil 49 on the basis of the focus error signal and the track error signal to move the objective lens 44, so that the focal point of the optical disc 70 is adjusted. Servo control is performed so as to be positioned on the disk surface and on the recording track.

  The video / audio signal input / output unit 10 is connected to an external device such as a display, a speaker, and a television receiver (not shown). The video / audio signal input / output unit 10 outputs video and audio signals reproduced from the optical disc 70, An audio signal is input.

  The remote controller 11 is for operating various operations of the optical disc apparatus 1 and includes operation keys (all not shown) for operating various operations. In response to the operation of these keys, the remote controller 7 transmits a corresponding signal as an infrared signal. The remote control receiving unit 12 receives an infrared signal sent from the remote control 11 and outputs the signal to the control unit 20. The display unit 13 is provided on the front panel of the optical disc apparatus 1 main body, and displays the contents operated by the remote controller 11, the operation status of the optical disc apparatus 1, and the like.

  The jitter measurement unit 15 receives the data slice signal from the data slice signal generation unit 8 during the jitter measurement test, measures the jitter value, and outputs the jitter value to the control unit 20. The control unit 20 can also display the result on the display unit 13. The user can monitor the jitter value based on the jitter measuring unit 15 on the display unit 13.

  Here, recording / reproduction of information with respect to the optical disc 70 will be described. First, information is reproduced from the optical disk 70 by irradiating the optical disk 70 with light from the semiconductor laser 41 while rotating the optical disk 70 at a predetermined speed by the spindle motor 3 and receiving the reflected light by the photodetector 46. Then, the servo control unit 9 controls the current supply to the focusing coil 48 based on the focus error signal from the signal processing unit 7 to move the objective lens 44, and the condensing point of the light from the semiconductor laser 41 is the optical disc. The focus is turned on (focus pull-in) so as to be positioned on the 70th surface. Further, the servo control unit 9 controls the current supply to the tracking coil 49 based on the track error signal from the signal processing unit 7 to move the objective lens 44 so that the light condensing point of the light from the semiconductor laser 41 is desired. The track is turned on (track pull-in) so as to be positioned on the recording track.

  After the focus on and track on, the servo controller 9 controls the current supply to the focusing coil 48 and the tracking coil 49 based on the focus error signal and the track error signal to maintain the focus on state and the track on state. Thus, focusing servo control and tracking servo control are performed.

  Then, the RF signal output from the signal processing unit 7 in this servo state is input to the data slice signal generation unit 8, and the data slice signal generated by binarizing the RF signal by the data slice signal generation unit 8 is the control unit. 20 is input. The control unit 20 detects the presence or absence of pits formed on the optical disc 70 based on the data slice signal, reads the information recorded on the optical disc 70, and reproduces the read information as a video signal or an audio signal. The video / audio signal input / output unit 10 outputs the signal to an external device.

  Similarly, information is recorded on the optical disc 70 by forming pits on the optical disc 70 with light from the semiconductor laser 41 in a focusing and tracking servo state. At this time, the video signal and the audio signal input from the video / audio signal input / output unit 10 are encoded by the control unit 20, and the semiconductor laser 41 is controlled according to the encoded data under the control of the control unit 20. Light emission is controlled. Thereby, pits corresponding to the encoded data are formed on the recording track of the optical disc 70, and video and audio information is recorded. Pits can be formed by causing the semiconductor laser 41 to emit light at a higher output than when reading information.

  The optical disc apparatus 1 having the above configuration performs reproduction of information from the optical disc 70, recording of information on the optical disc 70, and the like by operating the remote controller 11 under the control of the control unit 20. Further, the optical disc apparatus 1 performs an initial operation of reading information recorded on the innermost circumference side of the optical disc 70 when the optical disc 70 is inserted under the control of the control unit 20. Then, based on the information read in the initial operation, the type and recording contents of the inserted optical disk 70 are determined, and subsequent operations such as recording and reproduction of information are controlled.

  In the following, adjustment of the skew angle of the optical pickup with respect to the optical disc 70 will be described in particular. Specifically, a method for adjusting the inclination of the rotation axis of the rotary table of the optical disc 70 will be described.

  FIG. 2 is a configuration diagram of the optical disk rotation mechanism and its periphery. Here, a view when viewed from above in the direction of the rotary table is shown.

  Referring to FIG. 2, the optical disk is attached to spindle motor 3 by a disk guide mechanism (not shown) and placed on the upper surface of fixed rotary table 112, and then the disk is attracted by a suction force generated by a magnet or the like (not shown). It rotates integrally with the spindle motor 3 while being sandwiched between the clamper 113 and the rotary table 112.

  The spindle motor 3 is firmly attached to the motor attachment plate 114 and is fixed to the chassis 115 via an adjustment mechanism described later.

  Two guide shafts 117 that guide the optical pickup 4 in the radial direction of the disk are attached and fixed to the chassis 115 via four fixing members 118. The optical pickup 4 is driven by a moving motor along the guide shaft 117 and moves freely in the disk radial direction.

  Next, the configuration of the adjustment mechanism will be described.

  FIG. 3 is a side view of an optical disk rotation mechanism.

  Referring to FIG. 3, spindle motor 3 is mounted on motor mounting plate 114.

  The motor mounting plate 114 is fixed between the chassis 115 by a support member such as a boss 122. Further, the spindle motor 3 is attached to a predetermined position of the motor attachment plate 114 by the positioning guide pins 124.

  Further, an adjustment screw 100 is provided so as to come into contact with the motor mounting plate 114. A compression spring is sandwiched between the outer periphery of a support member such as the boss 122 between the chassis 115 and the motor mounting plate 114.

  FIG. 4 is a diagram for explaining the connection between the motor mounting plate 114 and the chassis 115.

  As shown in FIG. 4, the fixing screws 102 and the bosses 122 are fixed via the compression springs 104. Further, it is fixed by a fixing screw 103 and a boss 123 through a compression spring 105. It is also assumed that the adjustment screw 100 can be screwed in from the outside. With this structure, stress is applied to the motor mounting plate 114 by screwing the adjusting screw 100. As a result, the support member has a structure via the compression spring, and the inclination of the motor mounting plate 114 changes. That is, the rotation shaft of the spindle motor 3 is inclined.

  In the present invention, the inclination of the motor mounting plate 114 is changed by screwing the adjustment screw from the outside with a single adjustment screw 100 to adjust the inclination of the rotation shaft of the spindle motor 3. The chassis 115 is provided with a plurality of adjustment holes as positions where adjustment screws are screwed from the outside. In FIG. 2, three adjustment holes H1 to H3 are shown as an example of the adjustment holes.

  While monitoring the jitter value indicating the quality of the RF signal read out by the optical pickup 4, the user drives the spindle motor 3 in various directions by screwing adjustment screws into predetermined adjustment holes of the plurality of adjustment holes. It is possible to adjust by tilting the rotation axis.

  According to the configuration of the present application, it is possible to adjust the jitter value by adjusting the rotation axis of the spindle motor 3 by applying stress to one part of the motor mounting plate 114 as one adjustment screw, thereby reducing the number of parts and reducing the cost. It is possible to provide an inexpensive optical disc apparatus. Moreover, since there is only one place where stress is applied by the adjusting screw, it is possible to suppress the problem of deformation of the member.

  Further, when adjusting the inclination of the rotating shaft, the jitter value is monitored and set to an optimum value in the vicinity of the middle circumference between the inner circumference and the outer circumference of the disk. Thereby, the displacement can be suppressed to about ½ by distributing the displacement of the inclination to the innermost periphery and the outermost periphery. Jitter measurement near the middle circumference can be realized by reading the TOC information of the disc, identifying the middle circumference address based on the start address and the end address, and moving the pickup 4.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

1 is a schematic block diagram of an optical disc device according to an embodiment of the present invention. FIG. 3 is a configuration diagram of an optical disk rotation mechanism and its surroundings. It is a side view of the rotation mechanism of an optical disk. It is a figure explaining the connection between the motor attachment board 114 and the chassis 115. FIG.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Optical disk apparatus, 2 Disk insertion detection part, 3 Spindle motor, 4 Optical pick-up, 5 Moving motor, 6 Laser drive part, 7 Signal processing part, 8 Data slice signal generation part, 9 Servo control part, 10 Video / audio signal input Output unit, 11 Remote control unit, 12 Remote control reception unit, 13 Display unit, 15 Jitter measurement unit, 20 Control unit, 100 Adjustment screw, 102, 103 Fixing screw, 104, 105 Compression spring, 112 Rotary table, 113 Disc clamper, 114 motor mounting plate, 115 chassis, 122 boss.

Claims (4)

A disk table for holding an optical disk;
A spindle motor that rotationally drives the disk table;
A motor mounting plate for mounting the spindle motor;
A support member for supporting the motor mounting plate;
A chassis to which the motor mounting plate is fixed via the support member;
An optical pickup for reading or writing a signal recorded on the optical disc by a light beam;
Adjusting means for adjusting an angle at which a light beam emitted from the optical pickup is irradiated to the optical disc;
Jitter measuring means for measuring a jitter value based on a signal output from the optical pickup;
Control means for controlling the entire apparatus,
The adjusting means includes a screw portion that comes into contact with a predetermined place of the motor mounting plate by external twisting,
The control means rotates the spindle motor to rotationally drive the disk table, reads a signal recorded by the optical pickup, and a jitter value is measured by the jitter measuring means based on the read signal. ,
By pressing the motor mounting plate by twisting the screw portion based on the measurement result of the jitter value from the jitter measuring means, the angle of the rotation shaft of the spindle motor rotational drive is adjusted,
The optical pickup is executed near the middle circumference between the inner circumference and the outer circumference of the optical disc,
The support member includes a spring;
The optical disk apparatus, wherein the motor mounting plate is coupled and fixed to the chassis via the spring. A disk table for holding an optical disk;
A spindle motor that rotationally drives the disk table;
A motor mounting plate for mounting the spindle motor;
A support member for supporting the motor mounting plate;
A chassis to which the motor mounting plate is fixed via the support member;
An optical pickup for reading or writing a signal recorded on the optical disc by a light beam;
Adjusting means for adjusting an angle at which a light beam emitted from the optical pickup is irradiated to the optical disc;
Jitter measuring means for measuring a jitter value based on a signal output from the optical pickup;
Control means for controlling the entire apparatus,
The adjusting means includes a screw portion that comes into contact with a predetermined place of the motor mounting plate by external twisting,
The control means rotates the spindle motor to rotationally drive the disk table, reads a signal recorded by the optical pickup, and a jitter value is measured by the jitter measuring means based on the read signal. ,
An optical disc apparatus, wherein an angle of a rotation shaft of the spindle motor is driven by pressing the motor mounting plate by twisting the screw portion based on a jitter value measurement result from the jitter measuring means.   The optical disc apparatus according to claim 2, wherein the optical pickup is executed in the vicinity of a middle circumference between an inner circumference and an outer circumference of the optical disc. The support member includes a spring;
The optical disk apparatus according to claim 2, wherein the motor mounting plate is coupled and fixed to the chassis via the spring.

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