JP3805699B2 - Optical head device, optical head support device, and optical disk device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an optical head device including an optical head for at least one of optically recording information on an optical disk and optically reproducing information from the optical disk, and an optical head support for supporting the optical head. The present invention relates to an optical disc apparatus including an optical head apparatus.
[0002]
[Prior art]
An optical disc apparatus is an apparatus that performs at least one of optically recording information on an optical disc that is a disk-shaped recording medium and optically reproducing information from the optical disc. The optical disc apparatus has an optical head that irradiates an optical disc with a light beam used for recording or reproducing information, and an optical head support device that supports the optical head to be movable with respect to the optical disc. In the present application, an assembly including the optical head and the optical head support device is referred to as an optical head device.
[0003]
Compared to a magnetic recording device represented by a hard disk device, the optical disk device has advantages such as that the recording medium can be exchanged and that the resistance to destruction of the head and the surface of the recording medium is high and the reliability is high. Therefore, the optical disk device is widely used as an external storage device in computers and various electronic file systems.
[0004]
On the other hand, the optical disk apparatus should be improved because it is difficult to increase the access speed for moving the optical head to a desired track because the weight of the optical head is large. In order to overcome this, many efforts have been made to reduce the weight of the optical head and improve the performance of the drive mechanism of the optical head.
[0005]
For example, Japanese Patent Application Laid-Open No. 2001-23198 uses a swing arm as an optical head support device in the same manner as a hard disk device, and the tip of the swing arm needs to include an objective lens in the entire optical system of the optical head. An optical head device having a minimum number of components is disclosed.
[0006]
JP-A-2-23546 discloses an optical head including a floating slider similar to the floating head in a hard disk device, an optical head attached to the slider, and a support portion for supporting the optical head. An apparatus is disclosed. The flying slider and the optical head are slightly lifted from the optical disk by the air flow generated between the optical disk rotating at high speed and the flying slider.
[0007]
Japanese Laid-Open Patent Publication No. 7-176070 includes a floating slider, an optical head attached to the slider, a leaf spring-like support portion for supporting the optical head, and the optical head on the surface of the optical disk. An optical head device is disclosed in which a floating control slider is provided with a drive device for focus control that moves in a vertical direction.
[0008]
[Problems to be solved by the invention]
In the optical head device disclosed in Japanese Patent Application Laid-Open No. 2001-23198, the tip of the swing arm is lighter than the conventional optical head, so that the access speed can be increased. However, in this head device, a tracking control drive mechanism and a focus control drive mechanism are provided at the base of the swing arm. Therefore, this optical head device requires many optical members and driving mechanisms, and there is a problem that it is difficult to achieve a reduction in size and weight of the entire optical head device.
[0009]
In addition, the optical head device disclosed in Japanese Patent Laid-Open No. 2-23546 can achieve high-speed access equivalent to that of a hard disk device. However, in this head device, the optical head has no drive means for focus control. For this reason, in this head device, for example, when the thickness of the protective layer in the optical disc is uneven, or the air flow velocity changes due to the change in the relative velocity between the optical head and the optical disc, the flying height of the slider and the optical head increases. When it fluctuates, there is a problem that the focal point of the light beam deviates from the surface on which information is recorded on the optical disc.
[0010]
Further, in the optical head device disclosed in Japanese Patent Laid-Open No. 7-176070, an assembly including a floating slider, an optical head, and a focus control drive device is attached to the tip of a leaf spring-like support portion. . Therefore, the support portion needs to have an appropriate rigidity for supporting an assembly having a large weight and an appropriate elasticity for moving the assembly following the surface shake of the optical disc. Therefore, this optical head device has a problem that it is difficult to design the material and shape of the support portion.
[0011]
The present invention has been made in view of such problems, and an object thereof is to provide an optical head device, an optical head support device, and an optical disc device that enable focus control of the optical head and high-speed access.
[0012]
[Means for Solving the Problems]
The optical head device of the present invention is
An optical head for optically recording information on an optical disk and / or optically reproducing information from the optical disk;
An optical head supporting device that supports the optical head so as to face the optical disc and moves the optical head in a direction crossing the track of the optical disc,
The optical head has a light source that emits light emitted to the optical disc, a light receiving element, and an optical system that irradiates the optical disc with light emitted from the light source and guides return light from the optical disc to the light receiving element,
The optical head support device is flexible, has a first support member that supports the optical head, and has higher rigidity than the first support member, and supports the first support member. A second support member that is rotatable so that the optical head supported by the optical head moves in a direction crossing the track of the optical disc, and an optical head moving device that moves the optical head in a direction perpendicular to the surface of the optical disc. Is.
[0013]
In the optical head device of the present invention, the optical head is supported movably by the first support member having flexibility, and indirectly supported by the second support member having higher rigidity than the first support member. Is done. As the second support member rotates, the optical head is moved in a direction crossing the track of the optical disk. The optical head is moved in a direction perpendicular to the surface of the optical disc by the optical head moving device.
[0014]
In the optical head device of the present invention, the optical head moving device is provided on one of the first support member and the second support member, and on the other of the first support member and the second support member. You may have a coil.
[0015]
In the optical head device of the present invention, the optical head contains a light source, a light receiving element, and an optical system, and floats above the optical disk with a predetermined interval between the optical disk and an air flow generated between the optical head and the rotating optical disk. You may have the housing | casing which does.
[0016]
The optical head support device of the present invention supports an optical head for optically recording information on an optical disc and / or reproducing information from the optical disc so as to face the optical disc. And an apparatus for moving the optical head in the direction crossing the track of the optical disk. The optical head support device has a flexible first support member for supporting the optical head, a rigidity higher than that of the first support member, and supports the first support member. A second support member that is rotatable so that the optical head supported by the support member moves in a direction transverse to the track of the optical disk, and an optical head movement for moving the optical head in a direction perpendicular to the surface of the optical disk. Device.
[0017]
In the optical head support device of the present invention, the optical head is supported by the first support member and the second support member, and the optical head is moved in the direction perpendicular to the surface of the optical disk by the optical head moving device. Further, when the second support member is rotated, the optical head is moved in a direction crossing the track of the optical disk.
[0018]
In the optical head support device of the present invention, the optical head moving device is provided on one of the first support member and the second support member, and on the other of the first support member and the second support member. May be provided.
[0019]
The optical disc apparatus of the present invention is
A rotating device for rotating the optical disc;
An optical head for optically recording information on an optical disk and / or optically reproducing information from the optical disk;
An optical head support device that supports the optical head so as to face the optical disc and moves the optical head in a direction crossing the track of the optical disc;
A drive device for driving the optical head support device,
The optical head has a light source that emits light emitted to the optical disc, a light receiving element, and an optical system that irradiates the optical disc with light emitted from the light source and guides return light from the optical disc to the light receiving element,
The optical head support device is flexible, has a first support member that supports the optical head, and has higher rigidity than the first support member, and supports the first support member. A second support member that can be rotated so that the optical head supported by the optical head moves in a direction transverse to the track of the optical disk, and an optical head moving device that moves the optical head in a direction perpendicular to the surface of the optical disk. And
The drive device rotates the second support member.
[0020]
In the optical disk device of the present invention, the optical head is supported by the first support member having flexibility so as to be movable, and is indirectly supported by the second support member having higher rigidity than the first support member. The As the second support member rotates, the optical head is moved in a direction crossing the track of the optical disk. The optical head is moved in a direction perpendicular to the surface of the optical disc by the optical head moving device.
[0021]
In the optical disk apparatus of the present invention, the optical head moving device is provided on one of the first support member and the second support member, and on the other of the first support member and the second support member. You may have a coil.
[0022]
In the optical disk apparatus of the present invention, the optical head houses a light source, a light receiving element, and an optical system, and floats above the optical disk with a predetermined interval between the optical disk and an air flow generated between the optical head and the rotating optical disk. You may have a housing | casing.
[0023]
In the optical disc apparatus of the present invention, a plurality of sets of optical heads, optical head support devices, and driving devices may be provided for one optical disc.
[0024]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
First, the configuration of an optical head device and an optical head support device according to an embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a plan view of the optical head device according to the present embodiment, and FIG. 2 is a side view of the optical head device according to the present embodiment.
[0025]
The optical head device and the optical head support device according to the present embodiment are used for an optical disk device according to the present embodiment to be described later. This optical disk apparatus is an apparatus that performs at least one of optically recording information on an optical disk that is a disk-shaped recording medium and optically reproducing information from the optical disk. An optical disc has an information recording surface that is a surface on which information is recorded. An optical disc has a plurality of tracks.
[0026]
As shown in FIGS. 1 and 2, the optical head device 1 according to the present embodiment performs at least one of optically recording information on an optical disk and optically reproducing information from the optical disk. And an optical head support device 20 according to the present embodiment for supporting the optical head 10 so as to face the optical disc and moving the optical head 10 in a direction crossing the track of the optical disc. Yes. In the following description, it is assumed that the optical head 10 performs both optically recording information on the optical disc and optically reproducing information from the optical disc. Note that the recording / reproducing method in the optical disc apparatus according to the present embodiment may be any method that includes irradiating the optical disc with light for recording or reproducing information. As the recording / reproducing system, there are a system using pits, a system using phase change, a magneto-optical system, and the like.
[0027]
The optical head support device 20 is flexible, has a first support member 21 that elastically supports the optical head 10, and is more rigid than the first support member 21. A second support member 22 to be supported and an optical head moving device 23 for moving the optical head 10 in a direction perpendicular to the surface of the optical disk are provided. The second support member 22 is rotatable so that the optical head 10 supported by the first support member 21 moves in a direction crossing the track of the optical disk.
[0028]
The second support member 22 has a bearing portion 24 and an arm portion 25 extending in one direction from the bearing portion 24. The bearing portion 24 is rotatably attached to the shaft 29. The shaft 29 is fixed with respect to a housing of an optical disk device described later. The arm part 25 is plate-shaped. The second support member 22 has sufficient rigidity so as not to be easily deformed in a normal use state.
[0029]
A tracking control coil 31 is attached to the opposite side of the bearing portion 24 from the arm portion 25. In the optical disc apparatus, two magnets 32 are provided so as to face each other with a part of the coil 31 sandwiched from above and below, and two magnets 33 are provided so as to face each other with a part of the coil 31 sandwiched from above and below. Yes. In the coil 31, a portion sandwiched between the two magnets 32 and a portion sandwiched between the two magnets 33 are located on substantially opposite sides. The magnets 32 and 33 are fixed to the housing of the optical disc apparatus. The magnets 32 and 33 generate a vertical magnetic field in FIG. When a current is passed through the coil 31, a force is generated in the coil 31 in the direction of rotation about the shaft 29. By this force, the arm portion 25 rotates about the shaft 29. The coil 31 and the magnets 32 and 33 constitute a drive device 30 that drives the optical head support device 20.
[0030]
The first support member 21 has a leaf spring shape that is long in one direction. The length of the first support member 21 is shorter than the length of the second support member 22. One end portion of the first support member 21 is fixed to one surface (the upper surface in FIG. 2) of the arm portion 25 at an intermediate position in the longitudinal direction of the arm portion 25. The other end portion of the first support member 21 is disposed in the vicinity of the distal end portion of the arm portion 25. Further, the first support member 21 is bent so that the other end portion is separated from one surface of the arm portion 25. At the other end of the first support member 21, the optical head 10 is attached to the surface (the upper surface in FIG. 2) that is away from the arm portion 25 of the two surfaces of the first support member 21. Yes.
[0031]
The optical head moving device 23 includes a focus control coil 26 provided on the first support member 21 and a magnet 27 provided on the arm portion 25. The focus control coil 26 is attached to a position corresponding to the optical head 10 on the surface close to the arm portion 25 (the lower surface in FIG. 2) of the two surfaces of the first support member 21. The magnet 27 is attached to a position close to the focus control coil 26 on one surface of the arm portion 25 (the upper surface in FIG. 2). FIG. 3 shows the positional relationship among the optical head 10, the focus control coil 26, and the magnet 27 when viewed from the lower side in FIG. 2. The arrangement of the focus control coil 26 and the magnet 27 may be the reverse of the above description.
[0032]
The magnet 27 generates a horizontal magnetic field in FIGS. When a current is passed through the focus control coil 26, a vertical force in FIG. 2 is generated in the coil 26. By this force, the optical head 10 moves in the vertical direction with respect to the arm portion 25. Further, the vertical position of the optical head 10 can be controlled by controlling the magnitude of the current flowing through the coil 26.
[0033]
Next, the configuration and operation of the optical head 10 will be described in detail with reference to FIGS. 4 is a plan view of the optical head 10 with a part of the housing removed, and FIG. 5 is a cross-sectional view of the optical head 10. As shown in FIGS. 4 and 5, the optical head 10 includes a housing 11. The casing 11 includes a rectangular plate-shaped substrate portion 11a, two side wall portions 11b that rise in a vertical direction from two side portions of the substrate portion 11a, and a plate disposed on the two side wall portions 11b. And a medium facing portion 11c. FIG. 4 shows the optical head 10 with the medium facing portion 11c removed.
[0034]
The medium facing portion 11c forms a medium facing surface that faces the optical disc that is a recording medium. In the medium facing portion 11c, a portion in the vicinity of the end portion (the right end portion in FIG. 5) on the inflow side of the air flow generated between the rotating optical disc is a tapered portion. When the optical disk rotates, an air flow that flows in from the tapered portion and passes between the optical disk and the housing 11 causes a lift force in a direction away from the optical disk in the housing 11. The casing 11 floats from the optical disk at a predetermined interval from the optical disk by this lift.
[0035]
On the substrate portion 11a, a semiconductor laser 12 as a light source that emits light irradiated on the optical disk, a light receiving element 13, a front monitor photodetector 14, and a hologram mirror 15 are provided. A circular opening is formed in the medium facing portion 11c, and an objective lens 16 is attached to the lower surface of the medium facing portion 11c so as to close the opening. In addition, one end of a flexible printed circuit board 17 is connected to the board part 11a. The other end portion of the flexible printed circuit board 17 is connected to a circuit in an optical disk device to be described later. The upper surface of the substrate portion 11a and the lower surface of the medium facing portion 11c are both surfaces that reflect light.
[0036]
The hologram mirror 15 is disposed directly below the objective lens 16 and is inclined at an angle of 45 ° with respect to the optical axis of the objective lens 16. The hologram mirror 15 is a reflection type diffraction grating.
[0037]
The light receiving element 13 has light receiving portions 13a to 13d divided into four. Each of the light receiving portions 13a to 13d is configured by a photodiode, for example.
[0038]
The semiconductor laser 12 emits light toward the hologram mirror 15. The front monitor photodetector 14 is disposed at a position for receiving a part of the light emitted from the semiconductor laser 12. The output signal of the photodetector 14 is used to automatically adjust the amount of light emitted from the semiconductor laser 12. The light emitted from the semiconductor laser 12 enters the hologram mirror 15. The reflected light (0th order light) from the hologram mirror 15 enters the objective lens 16. This light passes through the objective lens 16 and is irradiated onto the optical disc as a converged light beam. The light incident on the optical disc is reflected by the information recording surface in the optical disc and returns to the objective lens 16.
[0039]
The return light from the optical disk passes through the objective lens 16 and enters the hologram mirror 15. The + 1st order diffracted light emitted from the hologram mirror 15 is reflected once by the lower surface of the medium facing portion 11 c and enters the light receiving portions 13 a and 13 b of the light receiving element 13. Further, the + 1st order diffracted light enters the light receiving portions 13a and 13b while converging. On the other hand, the −1st order diffracted light emitted from the hologram mirror 15 is reflected on the upper surface of the substrate portion 11 a, then reflected on the lower surface of the medium facing portion 11 c, and enters the light receiving portions 13 c and 13 d of the light receiving element 13. The −1st-order diffracted light once converges so as to have the smallest diameter before the light receiving portions 13c and 13d, and then enters the light receiving portions 13c and 13d as diverging light. The hologram mirror 15 may have a function of converging or diverging + 1st order diffracted light and −1st order diffracted light.
[0040]
In the light receiving element 13, the directions of the boundary lines of the light receiving portions 13a and 13b and the boundary lines of the light receiving portions 13c and 13d correspond to the track direction on the optical disc.
[0041]
Here, with reference to FIG. 6 to FIG. 8, a detection method of the focus error signal, the tracking error signal, and the information reproduction signal in the present embodiment will be described. FIG. 6 shows two light fluxes incident on the light receiving element 13 in a state where the light irradiated from the objective lens 16 to the optical disc has the smallest diameter on the information recording surface of the optical disc (hereinafter referred to as a focused state). In the in-focus state, the diameter of the light beam incident on the light receiving portions 13a and 13b of the light receiving element 13 is equal to the diameter of the light beam incident on the light receiving portions 13c and 13d.
[0042]
FIG. 7 shows two light beams incident on the light receiving element 13 in a state where the distance between the objective lens 16 and the optical disk is smaller than that in the focused state. In this state, the diameter of the light beam incident on the light receiving portions 13a and 13b of the light receiving element 13 is larger than the diameter of the light beam incident on the light receiving portions 13c and 13d.
[0043]
FIG. 8 shows two light beams incident on the light receiving element 13 in a state where the distance between the objective lens 16 and the optical disk is larger than that in the focused state. In this state, the diameter of the light beam incident on the light receiving portions 13c and 13d of the light receiving element 13 is larger than the diameter of the light beam incident on the light receiving portions 13a and 13b.
[0044]
Further, when the light emitted from the objective lens 16 to the optical disk accurately follows the track on the optical disk, the centers of the two light beams incident on the light receiving element 13 are on the boundary line between the light receiving parts 13a and 13b and the light receiving part. They are arranged on the boundary lines 13c and 13d, and there is no difference in intensity distribution on both sides of each boundary line in each light flux. When the light applied to the optical disk from the objective lens 16 deviates in one direction from the track, the intensity distribution of the two light beams incident on the light receiving element 13 changes, and each part incident on the light receiving portions 13a and 13c in each light beam It becomes darker than each part incident on the light receiving parts 13b and 13d. Similarly, when the light applied to the optical disk from the objective lens 16 is shifted in the opposite direction, the intensity distribution of the two light beams incident on the light receiving element 13 changes, and each part incident on the light receiving portions 13b and 13d is changed in each light beam. , It becomes darker than each part incident on the light receiving parts 13a, 13c.
[0045]
From the above, assuming that the outputs of the light receiving portions 13a, 13b, 13c, and 13d are A, B, C, and D, the focus error signal FE, the tracking error signal TE, and the information reproduction signal RF are respectively expressed by the following equations. It can be obtained by performing an operation to represent.
[0046]
FE = (A + B)-(C + D)
TE = (A + C)-(B + D)
RF = A + B + C + D
[0047]
A conductive pattern connected to the semiconductor laser 12, the light receiving element 13, and the photodetector 14 is formed on the substrate portion 11a. A flexible printed circuit board 17 is connected to this conductor pattern.
[0048]
Next, the operation of the optical head device 1 according to the present embodiment will be described. In this optical head device 1, the optical head 10 is movably supported by a flexible first support member 21, and indirectly by a second support member 22 having higher rigidity than the first support member 21. Supported by The optical head 10 is moved in a direction perpendicular to the surface of the optical disk 40 by the optical head moving device 23. The optical head moving device 23 includes a focus control coil 26 attached to the first support member 21 and a magnet 27 attached to the arm portion 25. Further, the optical head support device 20 is driven by the drive device 30 including the coil 31 and the magnets 32 and 33 so that the arm portion 25 rotates. Thereby, the optical head 10 is moved in a direction crossing the track of the optical disk.
[0049]
Next, the positional relationship between the optical head device 1 and the optical disk in the optical disk apparatus according to the present embodiment will be described with reference to FIGS. FIG. 9 shows the optical disk 40 and the optical head device 1 disposed below the optical disk 40. FIG. 10 shows the optical disk 40 and the optical head device 1 disposed above the optical disk 40. The optical disc 40 is attached to the spindle 41. The spindle 41 is rotated by a spindle motor 42. As shown in FIGS. 9 and 10, in the optical disk device according to the present embodiment, the optical head device 1 may be disposed below the optical disk 40 or may be disposed above the optical disk 40. . In any case, the optical head device 1 is arranged so that the optical head 10 faces the optical disc 40. The spindle 41 and the spindle motor 42 correspond to the rotating device in the present invention.
[0050]
Further, in the optical disk device according to the present embodiment, only one set of the optical head device 1 (the optical head 10 and the optical head support device 20) and the driving device 30 may be provided for one optical disk 40. A plurality of sets may be provided. FIG. 11 shows an example of the arrangement of two sets of the optical head device 1 and the driving device 30 provided for one optical disc 40. In an optical disc apparatus in which a plurality of sets of optical head devices 1 and driving devices 30 are provided for one optical disc 40, recording or reproduction can be performed simultaneously on a plurality of tracks on the optical disc 40.
[0051]
Next, the configuration of the optical disc apparatus according to the present embodiment will be described with reference to FIG. The optical disk apparatus according to the present embodiment includes a spindle 41 to which the optical disk 40 is attached, a spindle motor 42 that rotates the spindle 41, and a rotation control circuit 43 that controls the rotation speed of the optical disk 40 by controlling the spindle motor 42. And.
[0052]
The optical disc apparatus further includes the optical head device 1 (the optical head 10 and the optical head support device 20) and the driving device 30 described above.
[0053]
The optical disc apparatus further includes a semiconductor laser drive control circuit 44 for controlling the drive of the semiconductor laser 12 in the optical head 10 and a focus error signal FE and a tracking error signal TE based on the output signal of the light receiving element 13 in the optical head 10. And a signal processing circuit 45 that generates and outputs an information reproduction signal RF, a focus control circuit 46 that controls the optical head moving device 23, and a tracking control circuit 47 that controls the driving device 30.
[0054]
The optical disk apparatus further receives the output signal of the signal processing circuit 45, and also controls the rotation control circuit 43, the semiconductor laser drive control circuit 44, the focus control circuit 46, and the tracking control circuit 47, and the optical disk apparatus. A drive interface 48 that exchanges signals between an external device and the drive controller 50 is provided.
[0055]
FIG. 13 is a block diagram showing the configuration of the drive controller 50. The drive controller 50 includes a central processing unit (hereinafter referred to as CPU) 51, a read only memory (hereinafter referred to as ROM) 52, a random access memory (hereinafter referred to as RAM) 53, and a drive controller. An input / output control unit 54 that exchanges data with 50 external circuits and a bus 55 that connects them to each other are provided. The CPU 51 performs various control functions in the optical disc apparatus by executing programs recorded in the ROM 52 using the RAM 53 as a work area.
[0056]
In the optical disk apparatus shown in FIG. 12, the rotation control circuit 43 controls the spindle motor 42 based on a command from the drive controller 50, so that the rotation speed of the optical disk 40 is controlled. Further, the semiconductor laser drive control circuit 44 controls the drive of the semiconductor laser 12 in the optical head 10 based on a command from the drive controller 50, whereby the emitted light of the semiconductor laser 12 is controlled. Specifically, the control of the emitted light of the semiconductor laser 12 is the intensity of the emitted light, the pulse width when the semiconductor laser 12 is driven by a pulse, and the like.
[0057]
In the optical disk apparatus shown in FIG. 12, the focus error signal FE, the tracking error signal TE, and the information reproduction signal RF are generated by the signal processing circuit 45 based on the output signal of the light receiving element 13 in the optical head 10. . These signals are sent to the drive controller 50.
[0058]
The drive controller 50 controls the focus control circuit 46 based on the focus error signal FE, and the focus control circuit 46 controls the optical head moving device 23. Thereby, focus control is performed so that the in-focus state is always achieved regardless of the surface shake of the optical disc 40.
[0059]
The drive controller 50 controls the tracking control circuit 47 based on the tracking error signal TE, and the tracking control circuit 47 controls the driving device 30. Thereby, tracking control is performed so that the light emitted from the optical head 10 follows the track. The tracking control circuit 47 also controls the drive device 30 based on a command from the drive controller 50 to control access for moving the optical head 10 to a desired track.
[0060]
As described above, in the present embodiment, the optical head 10 is movably supported by the first support member 21 having flexibility, and the second support member has higher rigidity than the first support member 21. 22 indirectly supported. The second support member 22 is rotated so that the optical head 10 moves in a direction crossing the track of the optical disk 40. Therefore, according to the present embodiment, access for moving the optical head 10 to a desired track can be performed as fast as the hard disk device.
[0061]
Further, in the present embodiment, the optical head 10 is placed on the surface of the optical disc 40 by the focus control coil 26 provided on the first support member 21 and the magnet 27 provided on the second support member 22. It is moved in the vertical direction. Therefore, according to the present embodiment, the focus control of the optical head 10 can be performed with a simple configuration.
[0062]
In the present embodiment, the first support member 21 having flexibility supports the optical head 10 so that the optical head 10 can be moved in a direction perpendicular to the surface of the optical disk 40, while providing a second support with high rigidity. The member 22 moves the optical head 10 in a direction crossing the track of the optical disk 40. Thus, the functions of the first support member 21 and the second support member 22 are different. Therefore, what is necessary is just to design the 1st supporting member 21 and the 2nd supporting member 22 so that each function can be exhibited. Therefore, according to the present embodiment, the design of the optical head support device 20 is facilitated.
[0063]
In the present embodiment, the optical head 10 disposed at the tip of the optical head support device 20 includes the semiconductor laser 12 as the light source, the light receiving element 13, and the light emitted from the semiconductor laser 12 on the optical disc 40. And an optical system that guides return light from the optical disc 40 to the light receiving element 13. Therefore, according to the present embodiment, the configuration of the optical head device 1 is simplified as compared with the case where the constituent elements of the optical head are divided and arranged at the tip portion and the base portion of the arm.
[0064]
Further, in the present embodiment, the optical head 10 has the casing 11 that floats above the optical disk 40 with a predetermined gap between the optical head 40 and the optical disk 40 by an air flow generated between the optical head 10 and the rotating optical disk 40. . Therefore, according to the present embodiment, the distance between the optical head 10 and the optical disk 40 can be kept substantially constant with a simple configuration. Further, by using the flying of the optical head 10 by the air flow and the control method using the focus control coil 26 and the magnet 27, the position of the optical head can be controlled with higher accuracy.
[0065]
In addition, this invention is not limited to the said embodiment, A various change is possible. For example, the configuration of the optical head is not limited to the configuration in the embodiment, and can be arbitrarily designed.
[0066]
【The invention's effect】
As explained above, claim 1 Or 2 The optical head device according to claim 1, 3 The optical head support device according to claim 1 or claim 4 to 6 In the optical disk device according to any one of the above, the optical head is indirectly supported by the second support member that is movably supported by the first support member having flexibility and that has higher rigidity than the first support member. Supported by As the second support member rotates, the optical head is moved in a direction crossing the track of the optical disk. The optical head is moved in a direction perpendicular to the surface of the optical disc by the optical head moving device. Therefore, according to the present invention, there is an effect that the focus control of the optical head and high-speed access are possible.
[0067]
Claims 2 Optical head device or claim 5 In the described optical disc apparatus, the optical head has a housing that floats above the optical disc with a predetermined gap between the optical disc and an optical disc by an air flow generated between the optical disc and the rotating optical disc. Therefore, according to the present invention, there is an effect that the distance between the optical head and the optical disk can be kept substantially constant with a simple configuration.
[Brief description of the drawings]
FIG. 1 is a plan view of an optical head device according to an embodiment of the present invention.
FIG. 2 is a side view of an optical head device according to an embodiment of the present invention.
3 is an explanatory diagram showing a positional relationship among an optical head, a focus control coil, and a magnet when viewed from below in FIG. 2;
FIG. 4 is a plan view of an optical head according to an embodiment of the present invention in a state where a part of a housing is removed.
FIG. 5 is a cross-sectional view of an optical head according to an embodiment of the present invention.
FIG. 6 is an explanatory diagram for describing a detection method of a focus error signal, a tracking error signal, and an information reproduction signal according to an embodiment of the present invention.
FIG. 7 is an explanatory diagram for describing a detection method of a focus error signal, a tracking error signal, and an information reproduction signal according to an embodiment of the present invention.
FIG. 8 is an explanatory diagram for explaining a detection method of a focus error signal, a tracking error signal, and an information reproduction signal according to an embodiment of the present invention.
FIG. 9 is an explanatory diagram for explaining a positional relationship between the optical head device and the optical disc in the optical disc apparatus according to the embodiment of the present invention.
FIG. 10 is an explanatory diagram for explaining a positional relationship between the optical head device and the optical disc in the optical disc apparatus according to the embodiment of the present invention.
FIG. 11 is an explanatory diagram showing an example of the arrangement of two sets of optical head devices and driving devices provided for one optical disc.
FIG. 12 is an explanatory diagram showing a configuration of an optical disc device according to an embodiment of the present invention.
13 is a block diagram showing a configuration of a drive controller in FIG. 12. FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Optical head apparatus, 10 ... Optical head, 11 ... Housing | casing, 12 ... Semiconductor laser, 13 ... Light receiving element, 14 ... Photodetector for front monitor, 15 ... Hologram mirror, 16 ... Objective lens, 20 ... Optical head support Device: 21 ... first support member, 22 ... second support member, 23 ... optical head moving device, 24 ... bearing portion, 25 ... arm portion, 26 ... focus control coil, 27 ... magnet, 30 ... drive device 31 ... Coil for tracking control, 32, 33 ... Magnet, 40 ... Optical disk.

Claims (6)

An optical head for optically recording information on an optical disk and / or optically reproducing information from the optical disk;
An optical head supporting device that supports the optical head so as to face the optical disc and moves the optical head in a direction crossing a track of the optical disc,
The optical head includes a light source that emits light emitted to the optical disk, a light receiving element, and an optical system that irradiates the optical disk with light emitted from the light source and guides return light from the optical disk to the light receiving element. And
The optical head support device is flexible, has a first support member that supports the optical head, and is more rigid than the first support member, supports the first support member, and A second support member rotatable so that the optical head supported by the first support member moves in a direction crossing the track of the optical disc, and light for moving the optical head in a direction perpendicular to the surface of the optical disc have a head moving device,
The first support member and the second support member are both plate-shaped long in one direction,
The length of the first support member is shorter than the length of the second support member,
One end of the first support member is fixed to one surface of the second support member at an intermediate position in the longitudinal direction of the second support member, and the other end of the first support member is , Disposed near the tip of the second support member,
The optical head is attached to the other end of the first support member,
The optical head moving device includes a magnet provided on one of the first support member and the second support member, and a coil provided on the other of the first support member and the second support member. And
The optical head device according to claim 1, wherein the magnet or the coil provided on the second support member is attached to the one surface of the second support member . The optical head has a housing that houses the light source, the light receiving element, and the optical system, and that floats above the optical disc with a predetermined gap between the optical disc and an air flow generated between the optical disc and the rotating optical disc. The optical head device according to claim 1 . An optical head for performing at least one of optically recording information on the optical disc and optically reproducing information from the optical disc is supported so as to face the optical disc, and the optical head is mounted on the optical disc. An optical head support device that moves in a direction crossing a track,
A flexible first support member for supporting the optical head;
Rigid than the first support member, supports the first support member, and can rotate so that the optical head supported by the first support member moves in a direction crossing the track of the optical disk. A second support member,
An optical head moving device for moving the optical head in a direction perpendicular to the surface of the optical disc ;
The first support member and the second support member are both plate-shaped long in one direction,
The length of the first support member is shorter than the length of the second support member,
One end of the first support member is fixed to one surface of the second support member at an intermediate position in the longitudinal direction of the second support member, and the other end of the first support member is , Disposed near the tip of the second support member,
The optical head is attached to the other end of the first support member,
The optical head moving device includes a magnet provided on one of the first support member and the second support member, and a coil provided on the other of the first support member and the second support member. And
The optical head support device , wherein the magnet or the coil provided on the second support member is attached to the one surface of the second support member . A rotating device for rotating the optical disc;
An optical head for optically recording information on an optical disk and / or optically reproducing information from the optical disk;
An optical head support device that supports the optical head so as to face the optical disc and moves the optical head in a direction crossing a track of the optical disc;
A drive device for driving the optical head support device;
The optical head includes a light source that emits light emitted to the optical disk, a light receiving element, and an optical system that irradiates the optical disk with light emitted from the light source and guides return light from the optical disk to the light receiving element. And
The optical head support device is flexible, has a first support member that supports the optical head, and is more rigid than the first support member, supports the first support member, and A second support member rotatable so that the optical head supported by the first support member moves in a direction crossing the track of the optical disc, and light for moving the optical head in a direction perpendicular to the surface of the optical disc A head moving device,
The drive device rotates the second support member ,
The first support member and the second support member are both plate-shaped long in one direction,
The length of the first support member is shorter than the length of the second support member,
One end of the first support member is fixed to one surface of the second support member at an intermediate position in the longitudinal direction of the second support member, and the other end of the first support member is , Disposed near the tip of the second support member,
The optical head is attached to the other end of the first support member,
The optical head moving device includes a magnet provided on one of the first support member and the second support member, and a coil provided on the other of the first support member and the second support member. And
The optical disk apparatus , wherein the magnet or coil provided on the second support member is attached to the one surface of the second support member . The optical head has a housing that houses the light source, the light receiving element, and the optical system, and that floats above the optical disc with a predetermined gap between the optical disc and an air flow generated between the optical disc and the rotating optical disc. The optical disc apparatus according to claim 4 . 6. The optical disc apparatus according to claim 4 , wherein a plurality of sets of the optical head, the optical head support device, and the driving device are provided for one optical disc.

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