JP2009252331A - Optical pickup apparatus and optical disk device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical pickup apparatus and an optical disk device, which stably hold an objective lens and which can be miniaturized. <P>SOLUTION: The optical pickup device is provided with a lens holding member 124 holding the objective lens, a fixing member 126 which is fixedly installed, a first magnet 127 arranged between the lens holding member and the fixing member, a second magnet 128 disposed on an opposite side of the first magnet across the lens holding member, projection members 131 and 231 which project in a direction of the first magnet or the second magnet from the lens holding member and can abut on a side in a direction parallel to a direction connecting the first magnet and the second magnet in the first magnet or the second magnet in the projection direction, and a supporting member 132 whose one end is connected to the projection member and whose other end is connected to the fixing member and which elastically supports the lens holding member. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an optical pickup device and an optical disc device.

  An optical disc device (drive device) records data on an optical disc such as a CD (compact disc), DVD, or Blu-ray disc, and reproduces data recorded on the optical disc. An optical pickup device is provided with an optical pickup device that irradiates an optical disc with laser light and receives reflected light from the optical disc. Patent Document 1 discloses an example of an optical pickup device.

  By the way, when data is written to or read from the optical disc, there is a demand for increasing the data transfer rate in the optical pickup device. To increase the data transfer speed, for example, (1) a method of increasing the rotational speed of the optical disk to increase the data transfer speed, and (2) two optical pickup devices are mounted on one optical disk device and two pickups are provided. There is a method of reading and writing data simultaneously on the device.

  Increasing the number of revolutions of the optical disk as described in (1) above requires a high output of the semiconductor laser for reading and writing data, but there is a limit to increasing the output of the semiconductor laser. Further, when the output of the semiconductor laser is high, the temperature of the optical pickup device rises due to heat generated during laser emission. Therefore, it is necessary to provide a bulky heat radiating member in the optical pickup device to suppress the temperature rise. However, since the weight of the optical pickup device becomes heavy, there is a problem that the controllability of the optical pickup device is affected.

  Further, as described in (2) above, when two optical pickup devices are mounted on one optical disc device, the optical pickup device is arranged in the radial direction of the optical disc (direction from the inner circumference to the outer circumference or from the outer circumference to the inner circumference). Two guide shafts are required for the movement. The guide shaft extends in two directions in the radial direction of the optical disc, centering on a spindle motor that rotates the optical disc. In such a configuration, since there are two drive mechanisms, there is a limit to the miniaturization of the entire optical disc apparatus, and for example, it becomes difficult to mount the optical disc apparatus on a portable video camera or the like that is carried and used. There was a problem.

JP 2007-35212 A

  By the way, in order to increase the data transfer speed in the optical pickup device, two optical components (for example, a laser diode, a collimator lens, etc.) and an actuator (for example, a biaxial actuator) are mounted in one pickup device. In addition, there is a method of simultaneously reading and writing data with two systems of optical components and actuators.

  However, the conventional biaxial actuator has a problem that the longitudinal direction of the suspension supporting the lens holder is long, so that even if two systems of actuators are arranged in parallel, one optical pickup device is enlarged. For example, in the case of a cartridge type recording medium in which an optical disk is built in a cartridge, it is necessary to insert two systems of biaxial actuators into the opening of the cartridge. However, a simple combination of conventional two-axis actuators has failed to establish a configuration that allows two types of actuators to be inserted into the opening of the cartridge.

  For example, the objective lens driving device of Patent Document 1 is a device having a single optical component configuration and actuator. In the objective lens driving device of Patent Document 1, an apparatus cover that covers the lens holder and the magnet is provided in order to restrict movement of the lens holder that holds the objective lens in the tracking direction. And the protrusion part provided in the apparatus cover controls the movement of a lens holder. Therefore, there is a problem that the entire objective lens driving device becomes large.

  Further, in the objective lens driving device of Patent Document 1, the wire that supports the lens holder is connected to the lens holder at one end and is connected to the support member that supports the wire at the other end. Therefore, in order to exhibit the elastic characteristics of the wire, if the length of the wire is increased, the distance between the lens holder on one end side and the support member on the other end side becomes longer. For this reason, there is a problem that the entire objective lens driving device becomes large from this point.

  Accordingly, the present invention has been made in view of the above problems, and an object of the present invention is to provide a new and improved light that can stably hold an objective lens and can be downsized. To provide a pickup device and an optical disk device.

  In order to solve the above problems, according to an aspect of the present invention, a lens holding member that holds an objective lens, a fixed member that is fixedly installed, and a first member provided between the lens holding member and the fixing member A magnet, a second magnet provided on the opposite side of the first magnet across the lens holding member, a first magnet direction or a second magnet direction protruding from the lens holding member, and a first in the protruding direction A projecting member capable of contacting the side surface in a direction substantially parallel to the direction connecting the first magnet and the second magnet in the magnet or the second magnet, one end connected to the projecting member, and the other end connected to the fixing member Thus, an optical pickup device having a support member that elastically supports the lens holding member is provided.

The protruding member may be provided so as to protrude from the lens holding member in a direction substantially parallel to a direction connecting the first magnet and the second magnet.
The protruding member may be provided on a side surface of the lens holding member that is substantially parallel to a direction connecting the first magnet and the second magnet.
The protruding members may be provided in pairs with the lens holding member interposed therebetween.

  In order to solve the above problem, according to another aspect of the present invention, a light emitting element that irradiates light toward an optical disc, an objective lens that can collect the light onto the optical disc, and a lens that holds the objective lens A holding member, a fixing member fixedly installed, a first magnet provided between the lens holding member and the fixing member, and a second magnet provided on the opposite side of the first magnet across the lens holding member. The magnet projects from the lens holding member in the first magnet direction or the second magnet direction, and is substantially parallel to the direction connecting the first magnet and the second magnet in the first magnet or the second magnet in the projecting direction. An optical disc comprising: a projecting member capable of contacting a side surface in the direction; and an optical pickup device having one end connected to the projecting member and the other end connected to a fixing member and a support member that elastically supports the lens holding member. An apparatus is provided.

The optical pickup device may be provided such that the direction connecting the first magnet and the second magnet is substantially perpendicular to the radial direction of the optical disc.
The optical pickup device is provided in a pair in a direction connecting the first magnet and the second magnet, and the optical pickup device provided in the pair has an optical disc in the direction connecting the first magnet and the second magnet. It may be provided so as to be substantially perpendicular to the radial direction.

  According to the present invention, the objective lens can be stably held and downsized.

  Exemplary embodiments of the present invention will be described below in detail with reference to the accompanying drawings. In addition, in this specification and drawing, about the component which has the substantially same function structure, duplication description is abbreviate | omitted by attaching | subjecting the same code | symbol.

  First, an optical disk device 100 according to a first embodiment of the present invention will be described with reference to FIG. FIG. 1 is a block diagram showing a configuration of an optical disc apparatus 100 according to the present embodiment.

  The optical disc apparatus 100 includes, for example, a spindle motor 101, a spindle motor driver 102, a control unit 103, a signal processing unit 104, an external interface 105, an optical pickup device 110, a laser driver 111, and a biaxial driver 112. And RF amplifier 113.

The spindle motor 101 receives a drive signal from the spindle motor driver 102. The spindle motor 101 rotates the disk table 20 (see FIG. 3) on which the optical disk 5 is placed at a predetermined speed.
The spindle motor driver 102 receives a control signal from the control unit 103 and generates a drive signal related to the rotational drive of the spindle motor 101. The spindle motor driver 102 sends the generated drive signal to the spindle motor 101.

The control unit 103 performs input / output of signals with the external interface 105. Further, the output signal output from the RF amplifier 113 is input to the control unit 103.
The control unit 103 generates a tracking error signal and a focus error signal based on the output signal output from the RF amplifier 113. The control unit 103 sends the generated tracking error signal and focus error signal to the two-axis driver 112.
Further, the control unit 103 generates a control signal for controlling the spindle motor 101 and the laser diode 151 based on the output signal output from the RF amplifier 113. The control unit 103 sends the generated control signal to the spindle motor driver 102 and the laser driver 111. Further, the control unit 103 sends a control signal to the signal processing unit 104.

  The signal processing unit 104 receives an output signal (RF signal) output from the RF amplifier 113 and a control signal output from the control unit 103. The signal processing unit 104 performs signal processing such as extracting data recorded on the optical disc 5 based on the RF signal and generating a reproduction signal. The external interface 105 accepts user operations.

  The optical pickup device 110 irradiates the optical disc 5 with laser light or receives light reflected by the optical disc 5. The optical pickup device 110 includes an objective lens 121 (see FIGS. 2 and 3), a biaxial actuator 120 (see FIGS. 2 and 3) for driving the objective lens 121, a laser diode 151 (see FIG. 2), and the like. is doing.

The objective lens 121 is driven while tracking control and focus control are performed by the biaxial actuator 120. The objective lens 121 irradiates the optical disk 5 with the laser light emitted from the laser diode 151. The objective lens 121 can collect laser light on the disk 5.
The biaxial actuator 120 is a drive device that causes the objective lens 121 to follow the optical disk 5 that rotates at high speed. The biaxial actuator 120 can drive the objective lens 121 in the biaxial direction of the focus direction and the tracking direction.
The laser diode 151 is an example of a light emitting element, and receives a drive signal from the laser driver 111 to emit laser light.

  Further, the optical pickup device 110 has a light receiving element (not shown) that receives the reflected light of the laser light. The light receiving element converts the received laser light into an electrical signal and outputs the signal to the RF amplifier 113.

  The laser driver 111 receives a control signal from the control unit 103 and generates a laser driving signal related to driving of the laser diode 151. The laser driver 111 sends the generated laser drive signal to the laser diode 151.

  The biaxial driver 112 receives a tracking error signal and a focus error signal from the control unit 103 and generates a tracking drive signal and a focus drive signal related to the follow-up drive of the objective lens 121. The biaxial driver 112 sends the generated tracking drive signal and focus drive signal to the biaxial actuator 120 of the optical pickup device 110.

  The RF amplifier 113 receives an output signal based on the reflected light of the laser beam from the optical pickup device 110. The RF amplifier 113 amplifies the output signal and sends the amplified signal to the control unit 103 and the signal processing unit 104.

  Next, the configuration of the optical pickup device 110 according to the present embodiment will be described with reference to FIG. FIG. 2 is a side view showing the internal configuration of the optical pickup device 110 according to the present embodiment.

  As shown in FIG. 2, the optical pickup device 110 includes, for example, an optical component including a laser diode 151, a collimator lens 152, a rising mirror 153, and a biaxial actuator 120. The optical pickup device 110 is configured by two identical systems of the same optical component and the biaxial actuator 120. As a result, the data transfer rate can be increased in reading data from the optical disk 5 and writing data to the optical disk 5.

  In FIG. 2, the arrangement configuration of the two systems of optical components and the biaxial actuator 120 is shown to be symmetrical, but the present invention is not limited to such an example. Other arrangement configurations may be used as long as the optical pickup device 110 can read data from the optical disk 5 and write data to the optical disk 5 in two systems.

  The laser diode 151 irradiates laser light in the direction of the rising mirror 153 via the collimator lens 152. Laser light emitted from the laser diode 151 is condensed on the optical disk 5 through the objective lens 121.

The collimator lens 152 changes the laser light from the laser diode 151 from divergent light to parallel light.
The rising mirror 153 has an inclined surface formed on the laser diode 151 side, reflects most of the laser light emitted from the laser diode 151 by 90 °, and guides the laser light toward the optical disk 5.

  In addition to the components described above, the optical pickup device 110 may include a light receiving element that receives laser light, a prism that guides the laser light reflected by the optical disk 5 to the light receiving element side, and the like.

Next, the positional relationship between the optical pickup device 110 and the biaxial actuator 120 according to the present embodiment will be described with reference to FIGS.
FIG. 3 is a plan view showing the biaxial actuator 120 according to the present embodiment, and shows the positional relationship with the cover 14 of the cartridge 10 of the cartridge type recording medium. A cover 14 in FIG. 3 is a cover on one side of the cartridge 10, and FIG. 3 is a state in which the cover 12 on the other side shown in FIG. 4 and the built-in optical disk 5 are removed. FIG. 4 is a side view showing the biaxial actuator 120 according to this embodiment, and shows a positional relationship with the cartridge 10 of the cartridge type recording medium.

  The biaxial actuator 120 of the optical pickup device 110 is disposed at a position as shown in FIGS. 3 and 4 when reading data on the optical disc 5 or writing data on the optical disc 5.

  The recording media shown in FIGS. 3 and 4 are cartridge type recording media in which an optical disk (not shown) on a disc is built in the cartridge 10. The cartridge 10 is about 1 cm thick, for example. The cartridge type recording medium is provided with an opening 16 so that data can be written or read during recording or reproduction. The opening 16 is formed with a long opening in the radial direction of the optical disc.

  As shown in FIGS. 3 and 4, the optical pickup device 110 has an objective lens 121, an actuator cover 122, a base 123, and a lens holder 124.

  The objective lens 121 and two lens holders 124 that hold the objective lens 121 are provided in one optical pickup device 110 so as to be perpendicular to the radial direction of the optical disc (tangential direction to the track direction of the optical disc). Placed in.

  The actuator cover 122 is provided with an opening so that the two objective lenses 121 are exposed. The actuator cover 122 covers components such as a lens holder 124 described later on the base 123. In the present embodiment, internal components such as the lens holder 124 do not come into contact with the actuator cover 122.

  3 and 4, the optical pickup device 110 and the disk table 20 are inserted into the opening 16 of the cartridge 10. By inserting the optical pickup device 110 and the disk table 20 into the opening 16 of the cartridge 10, the objective lens 121 comes close to the optical disk built in the cartridge 10, for example, about several hundred μm. After that, it is possible to read data recorded on the optical disc and write data to the optical disc.

In this embodiment, the two systems of optical components and the biaxial actuator 120 are configured so that the two objective lenses 121 are accommodated in the opening 16 of the existing cartridge 10. As a result, data can be read and written simultaneously by the two optical components and the two-axis actuator 120, so that the data transfer speed can be increased.
In addition, two optical components and two-axis actuator 120 are provided in one optical pickup device 110, and the entire optical disc device 100 is smaller than the case where two optical pickup devices are separately mounted on the optical disc device. Can be achieved.

  Next, the biaxial actuator 120 according to the present embodiment will be described with reference to FIGS. In this embodiment, two systems of two-axis actuators 120 are arranged in parallel. Each of the two-axis actuators 120 has the same configuration and function, and therefore, one of the two-axis actuators 120 will be mainly described.

  FIG. 5 is a perspective view showing the biaxial actuator 120 according to the present embodiment, and is a view of the biaxial actuator 120 as viewed from the upper right. FIG. 6 is a plan view showing the configuration of one biaxial actuator 120 of the two systems of biaxial actuators 120 according to this embodiment, and is a view of the biaxial actuator 120 as viewed from above. Although the biaxial actuator 120 shown in FIG. 5 and the biaxial actuator 120 shown in FIG. 6 have different configurations of the stoppers 131 and 231, other components have the same configuration and operation.

  The biaxial actuator 120 according to this embodiment includes a lens holder 124, a drive coil 125, a suspension fixing member 126, magnets 127 and 128, a stopper 131 (231), a suspension 132, and yokes 141, 142, and 143. Etc.

  The lens holder 124 is an example of a lens holding member, and holds the objective lens 121. The lens holder 124 has a substantially rectangular parallelepiped shape, and the objective lens 121 is placed on the upper surface. The lens holder 124 has a through hole (not shown) penetrating in the vertical direction at the center, and the objective lens 121 is installed on the upper part of the through hole. As a result, the laser light emitted from the laser diode 151 passes through the through hole and enters the objective lens 121. As shown in FIG. 5, the upper surface of the lens holder 124 is provided with a protruding member that surrounds the objective lens 121, and stably holds the objective lens 121.

  The lens holder 124 is disposed between the magnet 127 and the magnet 128. A drive coil 125 is installed on the side surface of the lens holder 124 facing the magnets 127 and 128. A stopper 131 (231) is installed on the side surface of the lens holder 124 in a direction substantially parallel to the direction connecting the magnet 127 and the magnet 128 (tangential direction in the track direction of the optical disk).

  The lens holder 124 is suspended by the suspension 132 via the stopper 131 (231).

  The drive coil 125 is installed on the side surface of the lens holder 124 facing the magnets 127 and 128. The drive coil 125 has a configuration normally applied to a biaxial actuator. For example, the drive coil 125 has one focusing drive coil and a pair of tracking drive coils arranged in the tracking control direction (also called the tracking direction, ie, the radial direction of the optical disk). Each coil of the drive coil 125 is formed by winding a metal wire such as a copper wire.

  The suspension fixing member 126 is an example of a fixing member, and is provided in parallel with the lens holder 124, the magnet 127, and the magnet 128 in a direction connecting the magnet 127 and the magnet 128. The length in the tracking direction of the suspension fixing member 126 is longer than the length in the tracking direction of the member to which the lens holder 124 and the stopper 131 (231) are coupled. Suspension 132 is connected to both ends of suspension fixing member 126. The suspension fixing member 126 is connected and fixed to, for example, the base 123 and the yoke 143 of the optical pickup device 110, and stably supports the suspension 132.

  The magnet 127 is an example of a first magnet, and is installed between the lens holder 124 and the suspension fixing member 126. The magnet 128 is an example of a second magnet, and is provided on the opposite side of the magnet 127 with the lens holder 124 interposed therebetween.

  The magnets 127 and 128 have, for example, a substantially rectangular parallelepiped shape. The length of the magnets 127 and 128 in the tracking direction is substantially the same as the length of the lens holder 124 in the tracking direction.

  The magnets 127 and 128 are fixed to the yoke 141 and the yoke 143, for example. The magnets 127 and 128 have a configuration that is normally applied to a biaxial actuator in which two magnets sandwich the lens holder, and detailed description of the magnetization of each of the magnets 127 and 128, the direction of the lines of magnetic force, and the like is omitted. Note that the biaxial actuator 120 configured with the two magnets 127 and 128 sandwiching the lens holder 124 is advantageous in that the lens holder 124 can be moved uniformly in the focusing direction and the tracking direction.

  When the optical disc apparatus 100 receives an impact from the outside, both ends of the magnet 128 in the tracking direction come into contact with the stopper 131 in the case of FIG. 5 and come into contact with the stopper 231 (stopper surface 231B) in the case of FIG. In the case of FIG. 6, both ends of the magnet 127 in the tracking direction are in contact with the stopper 231 (stopper surface 231A).

  The stoppers 131 are provided in pairs at both ends of the lens holder 124 in the tracking direction with the lens holder 124 interposed therebetween. The stopper 131 is an example of a protruding member. In the case of FIG. 5, the stopper 131 is formed to protrude from the lens holder 124 in the direction of the magnet 128. Further, as shown in FIG. 6, the stopper 231 of the present embodiment is formed so as to protrude from the lens holder 124 in both directions of the magnet 127 and the magnet 128.

  In the case of FIG. 5, the stopper 131 protruding in the direction of the magnet 128 can contact the side surface of the magnet 128 that is substantially parallel to the direction connecting the magnet 127 and the magnet 128. In the case of FIG. 6, the stopper 231 protruding in the direction of the magnet 128 can abut on the side of the stopper surface 231 </ b> A that is substantially parallel to the direction connecting the magnet 127 and the magnet 128. In addition, the stopper 231 protruding in the direction of the magnet 127 can be in contact with the side surface of the magnet 127 that is substantially parallel to the direction connecting the magnet 127 and the magnet 128 on the stopper surface 231B.

In the optical disc apparatus 100, for example, when receiving an impact from the outside, the lens holder 124 moves by an inertial force (for example, moves in the arrow direction (tracking direction) shown in FIG. 7). FIG. 7 is an enlarged plan view showing a stopper 231 portion of the biaxial actuator 120 according to the present embodiment shown in FIG.
Without the stopper 131 (231), a moment force may be generated in the suspension 132 depending on the moving direction of the lens holder 124 and the degree of impact, and the suspension 132 may be deformed.
However, since the stopper 131 (231) is formed as described above, the stopper 131 (231) comes into contact with the magnets 127 and 128, so that the suspension 132 can be prevented from being deformed. Further, since the stopper 131 (231) contacts the magnets 127 and 128, it is not necessary to provide a cover or the like for restricting the movement of the components of the biaxial actuator 120 outside the biaxial actuator 120.

  Unlike the stopper 131 in FIG. 5, the stopper 231 can stably restrict the movement of the lens holder 124 by adopting a shape protruding in both directions of the magnets 127 and 128 like the stopper 231 in FIG. 6. it can.

  Further, the stopper 131 (231) is connected to the one end 132a of the suspension 132 at the tip protruding to the magnet 128 side, as shown in FIGS. FIG. 8 is a plan view showing a suspension 132 portion of the biaxial actuator 120 according to the present embodiment shown in FIG.

The suspension 132 is an example of a support member. The suspension 132 is a plate spring member, for example, and is a plate-like member whose height (thickness) in the vertical direction when installed on the biaxial actuator 120 is thinner than that in the width direction.
The suspension 132 has one end 132 a connected to the stopper 131 (231) and the other end 132 b connected to the suspension fixing member 126. The suspension 132 elastically suspends the lens holder 124 via the stopper 131 (231).
The suspensions 132 are provided in pairs with the lens holder 124 in between. For example, as shown in FIG. 6, two suspensions 132 are provided in the vertical direction on one side.

  As shown in FIG. 8, the suspension 132 has a U-shape bent near both end portions 132a and 132b when viewed from above. In the suspension 132, suspension fixing portions are formed at both end portions 132a and 132b, and a spring effective portion effective as an elastic member is formed between the suspension fixing portions.

Here, the suspension fixing portion is a portion where the suspension 132 is fixed to another member, and is connected to the stopper 131 (231) and the suspension fixing member 126. The suspension fixing portion has a strength as a fixing member for fixing the suspension 132.
The spring effective portion is a portion that exhibits elastic performance as an elastic member of the suspension 132. The length of the effective spring portion should be as long as possible. When the length of the effective spring portion is short, the lens holder 124 moves so as to draw an arc centering on the suspension fixing member 126 side. Can be on a straight line.

Further, the suspension 132 may be formed so that the width in the vicinity of both end portions 132a and 132b is wider than the width of the spring effective portion using the degree of freedom of the shape of the leaf spring member. As a result, even when the suspension 132 is formed of a single plate-like member, the rigidity of the suspension fixing portion can be made higher than that of the spring effective portion only by partially forming the width.
Further, by partially forming a wide width, the suspension 132 can achieve both of ensuring elasticity as an elastic member and ensuring strength as a fixing member for fixing the suspension 132.

The yokes 141, 142, and 143 are, for example, metal members, and can prevent leakage of magnetic lines of force from the magnets 127 and 128 to the outside, and can prevent thermal demagnetization of the magnets 127 and 128.
The yoke 141 is, for example, a plate-like member that is long in the tracking direction, and fixes the magnet 127.

The yoke 142 is, for example, a plate-like member that is long in the tracking direction, and fixes the two magnets 128. The yoke 142 is disposed between the two magnets 128.
In the conventional one-axis biaxial actuator, a yoke is always provided on a magnet (corresponding to the magnet 128 of this embodiment) far from the suspension fixing member (corresponding to the suspension fixing member 126 of this embodiment). Therefore, when two conventional single-axis actuators are simply combined and arranged so that the lens holders 124 are arranged in parallel as in this embodiment, the yokes are arranged in a double manner.
However, the overall length in the longitudinal direction of the suspension 132 can be shortened by arranging one yoke 142 in common for the two magnets 128 as in this embodiment.

  The yoke 143 is fixed to the base 123, for example. The yoke 143 is connected to the yoke 141 and the yoke 142.

  The operation of the biaxial actuator 120 according to the present embodiment is as follows. That is, the biaxial actuator 120 drives the lens holder 124 in the focus control direction (focusing direction, that is, the traveling direction of the laser beam in the objective lens 121) when a focus drive signal is input to the drive coil 125. Further, the biaxial actuator 120 drives the lens holder 124 in the tracking direction when a tracking drive signal is input to the drive coil 125.

  On the other hand, when an external impact is applied to the optical disc apparatus 100 on which the biaxial actuator 120 is installed, the lens holder 124 moves by inertial force. The stopper 131 (231) comes into contact with the magnets 127 and 128. As a result, no moment force is generated in the suspension 132, and the suspension 132 can be prevented from being deformed.

  According to the embodiment, the stopper 131 (231) restricts movement in the tracking direction. Further, the stopper 131 (231) has a support portion of the suspension 132, and since the suspension 132 is connected to the tip portion of the stopper 131 (231), the spring effective portion of the suspension 132 can be made long. .

  This point will be described with reference to FIG. FIG. 9 is a schematic diagram (right of FIG. 9) showing the biaxial actuator 120 according to the present embodiment and a schematic diagram (left of FIG. 9) showing a conventional biaxial actuator.

  The conventional biaxial actuator includes, for example, a lens holder 24 that holds the objective lens 21, a support portion 31 provided on the lens holder 24, a suspension fixing member 26, a rod-like suspension 32, and the like. In the conventional biaxial actuator, the effective length of the spring of the suspension 32 is the length from the connection portion 32 a between the suspension 32 and the support portion 31 to the connection portion 32 b between the suspension 32 and the suspension fixing member 26.

  The conventional biaxial actuator needs to provide the support portion 31 on the lens holder 24 in order to fix and support the suspension 32. In order to increase the effective length of the spring, it is necessary to dispose the suspension fixing member 26 as far as possible from the lens holder. Furthermore, there is a problem that a mold part is required to fix the suspension 26, and the longitudinal direction of the suspension becomes long.

  On the other hand, according to the present embodiment, the suspension 132 has a U-shape. Therefore, since the conventional mold parts are not necessary, the same effective spring length as that of the conventional one can be ensured. As a result, the lens holder 124 and the suspension fixing member 126 can be brought closer to each other than before, and the overall length of the biaxial actuator 120 can be shortened. Then, as shown in FIGS. 3 and 4, two objective lenses 121 can be inserted into the opening 16 of the cartridge type recording medium.

  Further, the stopper 131 (231) of the present embodiment not only prevents plastic deformation of the suspension 132 due to the movement of the lens holder 124, but also protrudes toward the magnets 127 and 128, so that the effective length of the spring is ensured long. be able to. As a result, the biaxial actuator 120 can be reduced in size.

  In the present embodiment, the stopper 131 (231) shares a member that restricts the movement of the lens holder 124 and a member that supports the suspension 132. Therefore, the overall weight can be reduced as compared with a case where a member for restricting the movement of the lens holder and a member for supporting the suspension are separately provided. As a result, the lens holder 124 can be easily controlled, and the controllability (sensitivity) of the lens holder 124 can be improved.

  The preferred embodiments of the present invention have been described in detail above with reference to the accompanying drawings, but the present invention is not limited to such examples. It is obvious that a person having ordinary knowledge in the technical field to which the present invention pertains can come up with various changes or modifications within the scope of the technical idea described in the claims. Of course, it is understood that these also belong to the technical scope of the present invention.

For example, although the case where the biaxial actuator 120 is applied as a follow-up driving device for the objective lens 121 is described in the above embodiment, the present invention is not limited to such an example. For example, the tracking drive device of the objective lens 121 may be a triaxial actuator. At this time, the triaxial actuator can drive the objective lens 121 in the triaxial directions of the focus direction, the tracking direction, and the radial tilt direction.
A tilt drive coil is provided on the surface of the lens holder 124 facing the magnets 127 and 128. A pair of tilt drive coils are arranged in the tracking direction.

  In the above embodiment, the two optical components and the biaxial actuator 120 are the same component, but the present invention is not limited to this example. For example, the structure which has two laser diodes which irradiate a different wavelength may be sufficient.

Moreover, although the said embodiment demonstrated the case where the stopper 131 (231) was installed in the side surface of the lens holder 124 of the direction substantially parallel to the direction which connects the magnet 127 and the magnet 128, this invention is limited to this example. Not. For example, a stopper may be provided on the side surface of the lens holder 124 in a direction substantially perpendicular to the direction connecting the magnet 127 and the magnet 128.
At this time, the length of the magnets 127 and 128 in the tracking direction is shorter than that of the lens holder 124. As a result, the stopper protruding in the direction of the magnet 128 can come into contact with the side surface of the magnet 128 that is substantially parallel to the direction connecting the magnet 127 and the magnet 128. Further, the stopper protruding in the direction of the magnet 127 can come into contact with the side surface of the magnet 127 in a direction substantially parallel to the direction connecting the magnet 127 and the magnet 128.

  In the above embodiment, the stopper 131 protrudes only in the direction of the magnet 128, and the stopper 231 protrudes in both directions of the magnets 127 and 128. However, the present invention is not limited to this example. For example, the protruding member of the present invention may protrude only in the direction of the magnet 127.

1 is a block diagram showing a configuration of an optical disc device according to a first embodiment of the present invention. It is a side view which shows the internal structure of the optical pick-up apparatus which concerns on the embodiment. It is a top view which shows the biaxial actuator which concerns on the same embodiment. It is a side view which shows the biaxial actuator which concerns on the same embodiment. It is a perspective view which shows the biaxial actuator which concerns on the same embodiment. It is a top view which shows one structure among the biaxial actuators concerning the embodiment. It is an enlarged plan view which shows the stopper part of the biaxial actuator which concerns on this embodiment shown in FIG. It is a top view which shows the suspension part of the biaxial actuator which concerns on this embodiment shown in FIG. It is the schematic diagram which shows the biaxial actuator which concerns on the same embodiment, and the schematic diagram which shows the conventional biaxial actuator.

Explanation of symbols

DESCRIPTION OF SYMBOLS 5 Optical disk 100 Optical disk apparatus 101 Spindle motor 102 Spindle motor driver 103 Control part 104 Signal processing part 105 External interface 110 Optical pick-up apparatus 111 Laser driver 112 Two axis driver 113 RF amplifier 120 Two axis actuator 121 Objective lens 122 Actuator cover 123 Base 124 Lens Holder 125 Drive coil 126 Suspension fixing member 127, 128 Magnet 131, 231 Stopper 132 Suspension 141, 142, 143 Yoke 151 Laser diode 152 Collimator lens 153 Rising mirror

Claims (7)

A lens holding member for holding the objective lens;
A fixed member fixedly installed;
A first magnet provided between the lens holding member and the fixing member;
A second magnet provided on the opposite side of the first magnet across the lens holding member;
Projecting in the first magnet direction or the second magnet direction from the lens holding member, and connecting the first magnet and the second magnet in the first magnet or the second magnet in the projecting direction. A projecting member capable of contacting a side surface in a direction substantially parallel to the direction;
An optical pickup device comprising: a support member having one end connected to the protruding member and the other end connected to the fixing member and elastically supporting the lens holding member.   2. The optical pickup device according to claim 1, wherein the protruding member is provided to protrude from the lens holding member in a direction substantially parallel to a direction connecting the first magnet and the second magnet.   3. The optical pickup device according to claim 1, wherein the projecting member is provided on a side surface of the lens holding member that is substantially parallel to a direction connecting the first magnet and the second magnet.   The optical pickup device according to claim 1, wherein the protruding members are provided in pairs with the lens holding member interposed therebetween. A light emitting element that emits light toward the optical disc;
An objective lens capable of condensing the light on the optical disc;
A lens holding member for holding the objective lens, a fixing member fixedly installed, a first magnet provided between the lens holding member and the fixing member, and the first holding member sandwiching the lens holding member A second magnet provided on the opposite side of the magnet, and the lens holding member projecting in the first magnet direction or the second magnet direction, in the projecting direction of the first magnet or the second magnet A projecting member capable of contacting a side surface in a direction substantially parallel to a direction connecting the first magnet and the second magnet, one end connected to the projecting member, and the other end connected to the fixing member; And an optical pickup device having a support member that elastically supports the lens holding member.   6. The optical disc device according to claim 5, wherein the optical pickup device is provided so that a direction connecting the first magnet and the second magnet is substantially perpendicular to a radial direction of the optical disc. The optical pickup device is provided in a pair in a direction connecting the first magnet and the second magnet, and the optical pickup device provided in the pair includes the first magnet and the second magnet. The optical disc apparatus according to claim 5 or 6, wherein a direction connecting the two is provided so as to be substantially perpendicular to a radial direction of the optical disc.

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