JP2009176341A - Disk playback device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a disk playback device capable of maintaining a clearance between a pickup lens and a recording medium with a simple configuration. <P>SOLUTION: The disk playback device (1) includes a pickup lens (10) for receiving a light from a recording medium (2), a lens holder (20) for holding the pickup lens, a base (30) for movably holding the lens holder, and a separation mechanism (21) disposed in the lens holder that generates a force of a direction for separating the lens holder from the recording medium by an air flow generated by rotating the recording medium. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a disk reproducing apparatus, and more particularly to a disk reproducing apparatus having a mechanism for avoiding contact with a disk.

  In a disk reproducing apparatus, the density of a disk for recording and reproducing information is increasing. In order to perform recording and reproduction on such a high-density disk, it is necessary to make the spot diameter of the laser beam smaller. Therefore, in a playback apparatus compatible with BD (Blue-ray Disc) and HD-DVD (High Definition Digital Versatile Disc), a blue laser with a wavelength of 405 nm and a numerical aperture (NA) of 0.85 (for BD) or 0 Objective lenses such as .65 (for HD-DVD) are used. Further, when such a high NA objective lens is used, the working distance between the objective lens and the disk surface becomes very small (about 0.1 mm for BD, about 1 mm for HD-DVD), and the objective lens is There has been a problem that there is a high possibility that the disk surface will be damaged by contact with the disk surface.

  Therefore, the arm 4 that moves the head 3 that holds the objective lens along the information disk 2 receives the airflow generated by the rotation of the information disk 2 and the slider 5 that generates buoyancy is provided between the arm 4 and the information disk 2. An information recording / reproducing apparatus provided between the two is known (for example, Patent Document 1). In such an information recording / reproducing apparatus, a force in a direction away from the information disk 2 is applied to the arm 4 by the floating force generated by the slider 5, whereby the head 3 connected to the arm 4 is connected to the information disk 2. It is configured to prevent contact.

Japanese Patent Laying-Open No. 2003-257058 (5th page, FIG. 1)

  However, the air flow generated by the rotation of the information recording medium may cause the slider itself, which generates a floating force to float the entire arm that moves the head, to come into contact with the information recording medium, resulting in a risk of damaging the information recording medium. When there was an increase in sex, there was a problem. Furthermore, a slider that generates buoyancy that causes the entire arm that moves the head to float due to the airflow generated by the rotation of the information recording medium itself has a large structure, which is a factor that hinders cost increases and downsizing of the playback device. There was a problem of becoming.

  Accordingly, an object of the present invention is to provide a disc reproducing apparatus that can solve the above-mentioned problems.

  It is another object of the present invention to provide a disc reproducing apparatus that can maintain a clearance between a pickup lens and a disc with a simple configuration.

  The disk reproducing apparatus according to the present invention includes a pickup lens that receives light from the disk, a lens holder that holds the pickup lens, a base that holds the lens holder movably, and an air flow that is generated when the disk rotates. It has a separation mechanism disposed on the lens holder that generates a force in a direction to separate the lens holder from the disk.

  According to the disk reproducing apparatus according to the present invention, since the separation mechanism for generating the force in the direction of separating the lens holder from the disk is provided by the air flow generated by the rotation of the disk, the pickup lens and the disk are in contact with each other. It became possible to prevent the risk of doing.

  Further, according to the disk reproducing apparatus according to the present invention, since the separation mechanism for generating the force in the direction of separating from the disk is provided on the lightweight lens holder, the separation mechanism itself does not need to be enlarged, and the apparatus is substantially reduced. The risk of contact between the pickup lens and the disk can be prevented without increasing the overall size.

  Hereinafter, a disc reproducing apparatus according to the present invention will be described with reference to the drawings. However, it should be noted that the technical scope of the present invention is not limited to these embodiments, but extends to the invention described in the claims and equivalents thereof.

  FIG. 1 is a diagram showing a schematic configuration of a disc reproducing apparatus.

  The disc reproducing apparatus 1 includes an optical head 3 having various elements for reproducing (and / or recording) optical information from a disc 2 such as a CD, a DVD, a BD, an HD-DVD, and an MD, and a drive motor 6. Lead screw (feed screw) 4 as a main shaft for moving the disc 2 along the radial direction A, a guide 7 as a sub shaft, and a drive motor (not shown) for rotating the disc 2 in the direction of arrow B Etc.

  As shown in FIG. 1, the optical head (pickup) 3 reproduces (and / or reproduces) information from a guide portion 5 for engaging with the lead screw 4, an engaging portion 8 for engaging with the guide 7, and the disc 2. Or a pickup lens 10 for recording.

  FIG. 2 is a diagram showing a schematic configuration of the optical head 3 used in the reproducing apparatus 1 shown in FIG. 2A is a schematic perspective view of the optical head 3, and FIG. 2B is a cross-sectional view taken along the line XX ′ in FIG.

  The optical head 3 includes a pickup lens 10, a lens holder 20 that holds the pickup lens 10, and the lens holder 20 in a direction perpendicular to the disk 2 (focusing direction) and in a direction parallel to the rotation direction of the disk 2 (tracking direction). A base 30 or the like that is movably held is provided. The lens holder 20 is movably held by being connected to the base 30 by, for example, four wires or the like, but the wires and the like are omitted in FIG.

  An inclined convex portion 21 is provided at the end of the lens holder 20 at a location facing the disk 2 as a separation mechanism for separating the lens holder 20 from the disk 2. As the disk 2 rotates in the direction of arrow B (see FIG. 1), an air flow in the direction of arrow C is generated and flows into the space between the lens holder 20 and the base 30 and the disk 2. The flowing air flow changes in the direction of arrow D along the inclined shape of the convex portion 21. The lens holder 20 receives a force (lift) in the direction of arrow E away from the disk 2 in response to a change in the airflow.

  The lift force received by the lens holder 20 increases as the distance between the convex portion 20 and the disk 2 becomes narrower due to the air flow between them. Conversely, the wider the distance between the convex portion 20 and the disk 2, the weaker it becomes. Therefore, when the pickup lens 10 held by the lens holder 20 approaches the disk 2, the lift in the direction of arrow E increases and the pickup lens 10 is moved away from the disk 2. The possibility of damaging the disk 2 in contact with the disk 2 is extremely low.

  Since the weight of the lens holder 20 is sufficiently light compared to the base 30, the lead screw 4, the guide 7, and the like, the lens holder 20 can be easily separated from the disk 2 by the lift generated by the convex portion 21. Similarly, in order to obtain lift for separating the lens holder 20, it is not necessary to provide a very large convex portion 21, so that the size of the lens holder 20 itself is increased, which hinders downsizing of the reproducing apparatus. It will not be.

In the above example, the convex portion 21 has an inclined shape such that its cross section is a triangle. However, the shape of the convex portion 21 is not limited to this, and the cross section may be a blade cross-sectional shape or the like. good. The height (a) of the convex portion 21, the clearance (b) between the apex of the lens 10 and the disc 2, and the clearance (c) between the apex of the convex portion 21 and the disc 2 are a> 0 and b <c. The relationship is established.
FIG. 3 is a diagram showing a schematic configuration of another optical head 100. 3A is a schematic perspective view of the optical head 100, and FIG. 3B is a sectional view taken along line XX ′ in FIG.

  The optical head 100 can be used in the reproducing apparatus 1 instead of the optical head 3 and moves the pickup lens 10, the lens holder 110 that holds the pickup lens 10, and the lens holder 110 in the focusing direction and the tracking direction with respect to the disk 2. It has a base 30 or the like that can be held. The lens holder 110 is held movably by being connected to the base 30 by, for example, four wires or the like, but the wires and the like are omitted in FIG.

  The surface of the lens holder 110 is formed to have an overall inclination so that the lens holder itself functions as a separation mechanism for separating the lens holder 110 from the disk 2. As the disk 2 rotates in the direction of arrow B (see FIG. 1), an air flow in the direction of arrow C is generated and flows into the space between the lens holder 110 and the base 30 and the disk 2. The flowing air flow changes in the direction of arrow D along the inclined shape of the lens holder 110. The lens holder 110 receives a force (lift) in the direction of an arrow E that is separated from the disk 2 in response to a change in the airflow.

  The lift force received by the lens holder 110 increases as the distance between the lens holder 110 and the disk 2 becomes narrower due to the air flow between them. Conversely, the wider the distance between the lens holder 110 and the disk 2, the weaker. Therefore, when the pickup lens 10 held by the lens holder 110 approaches the disk 2, the lift in the direction of arrow E increases and the pickup lens 10 is moved away from the disk 2. The possibility of damaging the disk 2 in contact with the disk 2 is extremely low.

Since the weight of the lens holder 110 is sufficiently light as compared with the base 30, the lead screw 4, the guide 7, and the like, the lens holder 110 can be easily separated from the disk 2 by the lift generated by the lens holder 110. Similarly, since it is not necessary to enlarge the lens holder 110 itself in order to obtain a lift force for separating the lens holder 110, it does not hinder downsizing of the reproducing apparatus. The height (d) of the apex of the lens holder 110, the clearance (e) between the apex of the lens 10 and the disk 2, and the clearance (f) between the apex of the lens holder 110 and the disk 2 are d> 0 and e The relationship <f is established.
FIG. 4 is a diagram showing a schematic configuration of still another optical head 101. 4A is a schematic perspective view of the optical head 101, and FIG. 4B is a sectional view taken along line XX ′ in FIG.

  The optical head 101 can be used in place of the optical head 3 in the reproducing apparatus 1 and moves the pickup lens 10, the lens holder 120 that holds the pickup lens 10, and the lens holder 120 in the focusing direction and the tracking direction with respect to the disk 2. A base 31 or the like that can be held is provided. The lens holder 120 is movably held by being connected to the base 31 by, for example, four wires or the like, but the wires and the like are omitted in FIG.

  A part of the base 31 is provided with an opening 32 as a separation mechanism for separating the lens holder 120 from the disk 2. As the disk 2 rotates in the direction of arrow B (see FIG. 1), an air flow in the direction of arrow C is generated and flows into the opening 32 of the base 31 as indicated by arrow D. Since the air flow that has flowed into the lens holder 120, the lens holder 120 receives a force in the direction of an arrow E that is separated from the disk 2.

  As shown in FIG. 4B, the opening 32 is formed so as to be lowered toward the lower left in the drawing. When the lens holder 120 attempts to approach the recording medium 120, the air flow is changed to the lens holder 120. Designed to hit strongly. Accordingly, when the pickup lens 10 held by the lens holder 120 approaches the disk 2, the force in the direction of arrow E becomes strong, and the pickup lens 10 is moved away from the disk 2. The possibility of damaging the disk 2 in contact with the disk 2 is extremely low.

  5 and 6 are diagrams showing a schematic configuration of still another optical head 102. FIG. 5 is a schematic perspective view of the optical head 102, FIG. 6 (a) is a top view of the optical head 102, and FIG. 6 (b) is a sectional view taken along line XX ′ in FIG. 5 (a).

  The optical head 102 can be used in place of the optical head 3 in the reproducing apparatus 1, and moves the pickup lens 10, the lens holder 130 that holds the pickup lens 10, and the lens holder 130 in the focusing direction and the tracking direction with respect to the disk 2. It has a base 30 or the like that can be held. The lens holder 130 is movably held by being connected to the base 30 by, for example, four wires or the like, but the wires and the like are omitted in FIGS. 5 and 6.

  The lens holder 130 generally has a first wall 131 and a second wall 132 for controlling the air flow, and the lens holder itself functions as a separation mechanism for separating the lens holder 130 from the disk 2. An inclined portion 133 is formed so as to have an inclination. As the disk 2 rotates in the direction of arrow B (see FIG. 1), an air flow in the direction of arrow C is generated and flows into the space between the lens holder 130 and the disk 2. The flowing air flow is between the first wall portion 131 and the second wall portion 132 of the lens holder 130, and the flow changes in the direction of the arrow D along the inclined shape of the inclined portion 133. The lens holder 130 receives a force (lift) in the direction of an arrow E that is separated from the disk 2 in response to a change in the airflow. Here, in particular, the lens holder 130 has the first and second wall portions 131 and 132 as compared with the lens holder 110 shown in FIG. It becomes possible to guide between. Therefore, it is possible to increase the force (lifting force) acting in the direction in which the lens holder 130 is separated from the disk 2.

  The lift force received by the lens holder 130 becomes stronger as the distance between the lens holder 130 and the disk 2 becomes narrower due to the air flow between them. Conversely, the wider the distance between the lens holder 130 and the disk 2, the weaker. Therefore, when the pickup lens 10 held by the lens holder 130 approaches the disk 2, the lift in the direction of arrow E increases, and the pickup lens 10 is moved away from the disk 2. The possibility of damaging the disk 2 in contact with the disk 2 is extremely low.

  Since the weight of the lens holder 130 is sufficiently light compared to the base 30, the lead screw 4, the guide 7, and the like, the lens holder 130 can be easily separated from the disk 2 by the lift generated by the lens holder 130. Similarly, since it is not necessary to enlarge the lens holder 130 itself in order to obtain a lift force for separating the lens holder 130, it does not become a factor that hinders downsizing of the reproducing apparatus.

  7 and 8 are diagrams showing a schematic configuration of still another optical head 103. FIG. 7 is a schematic perspective view of the optical head 103, FIG. 8A is a top view of the optical head 103, FIG. 8B is an XX ′ sectional view in FIG. 8A, and FIG. c) is a YY ′ cross-sectional view in FIG.

  The optical head 103 can be used in place of the optical head 3 in the reproducing apparatus 1 and moves the pickup lens 10, the lens holder 20 that holds the pickup lens 10, and the lens holder 20 in the focusing direction and the tracking direction with respect to the disk 2. It has a base 33 or the like that can be held. The lens holder 20 is movably held by being connected to the base 33 by, for example, four wires or the like, but the wires and the like are omitted in FIGS.

  The lens holder 20 has the same shape as that shown in FIG. 2, and a convex portion 21 having an inclined shape at the end so as to function as a separation mechanism for separating the lens holder 20 from the disk 2. have. Furthermore, the end of the base 33 has a third wall portion 34 and a fourth wall portion 35 for controlling the air flow.

  When the disk 2 rotates in the direction of arrow B (see FIG. 1), an air flow in the direction of arrow C1 is generated and flows into the space between the lens holder 20 and the base 33 and the disk 2. The air flow that flows in is regulated by the third wall portion 34 and the fourth wall portion 35 of the base 33 as indicated by an arrow C 2, and the flow changes in the direction of the arrow D along the convex portion 21 of the lens holder 20. To do. The lens holder 20 receives a force (lift) in the direction of an arrow E that is separated from the disk 2 in response to a change in the airflow. Here, in particular, the lens holder 20 has the third wall portion 34 and the fourth wall portion 35 of the base 33 as compared with the case shown in FIG. And the disk 2 can be guided. Therefore, it is possible to increase the force (lift) that acts in the direction in which the lens holder 20 is separated from the disk 2.

  The lift force received by the lens holder 20 becomes stronger as the distance between the lens holder 20 and the disk 2 becomes narrower due to the air flow between them. Conversely, the wider the distance between the lens holder 20 and the disk 2, the weaker. Therefore, when the pickup lens 10 held by the lens holder 20 approaches the disk 2, the lift in the direction of arrow E increases and the pickup lens 10 is moved away from the disk 2. The possibility of damaging the disk 2 in contact with the disk 2 is extremely low.

  Since the weight of the lens holder 20 is sufficiently light compared with the base 33, the lead screw 4, the guide 7, and the like, the lens holder 20 can be easily separated from the disk 2 by the lift generated by the lens holder 20. Similarly, since it is not necessary to enlarge the lens holder 20 itself in order to obtain a lift force for separating the lens holder 20, it does not hinder downsizing of the reproducing apparatus.

  9 and 10 are diagrams showing a schematic configuration of still another optical head 104. FIG. 9 is a schematic perspective view of the optical head 104, FIG. 10 (a) is a top view of the optical head 104, FIG. 10 (b) is an XX ′ sectional view in FIG. 10 (a), and FIG. FIG. 10C is a YY ′ cross-sectional view in FIG.

  The optical head 104 can be used in place of the optical head 3 in the reproducing apparatus 1, and moves the pickup lens 10, the lens holder 130 that holds the pickup lens 10, and the lens holder 130 in the focusing direction and the tracking direction with respect to the disk 2. A base 36 or the like that can be held is provided. The lens holder 130 is movably held by being connected to the base 36 by, for example, four wires or the like, but the wires and the like are omitted in FIGS. 9 and 10.

  The lens holder 130 has the same shape as that shown in FIG. 6, and the first wall 131 and the second wall 132 for controlling the air flow, and the lens holder itself detaches the lens holder 130 from the disc 2. And an inclined portion 133 formed so as to have an overall inclination so as to function as a separation mechanism for separating from the distance. Further, the base 36 has an opening 32 formed so as to function as a separation mechanism for separating the lens holder 130 shown in FIG. 4 from the disk 2, and a third for controlling the air flow shown in FIG. A wall 34 and a fourth wall 35 are provided.

  As the disk 2 rotates in the direction of arrow B (see FIG. 1), an air flow in the direction of arrow C1 is generated. The generated airflow flows into the space between the lens holder 130 and the disk 2 through the opening 32 of the base 36 in the direction of the arrow C2. The air flow that flows in is restricted by the first wall portion 131 and the second wall portion 133 of the lens holder 130 as indicated by an arrow D, and is restricted by the third wall portion 34 and the fourth wall portion 35 of the base 36, The flow changes in the direction of arrow D along the inclined shape of the inclined portion 133. The lens holder 130 receives a force (lift) in the direction of an arrow E that is separated from the disk 2 in response to a change in the airflow. Here, in particular, since the lens holder 130 has the first wall portion 131 and the second wall portion 132, and the base 36 has the third wall portion 34 and the fourth wall portion 35, a large air flow is generated. It is possible to guide between the lens holder 130 and the disk 2. Therefore, it is possible to increase the force (lifting force) acting in the direction in which the lens holder 130 is separated from the disk 2.

  Since the weight of the lens holder 130 is sufficiently light compared with the base 36, the lead screw 4, the guide 7, and the like, the lens holder 130 can be easily separated from the disk 2 by the lift generated by the lens holder 130. Similarly, since it is not necessary to enlarge the lens holder 130 itself in order to obtain a lift force for separating the lens holder 130, it does not become a factor that hinders downsizing of the reproducing apparatus.

  As described above, as a method for obtaining lift by the lens holder, when the lens holder itself has a convex portion (see FIG. 2), when the lens holder has an inclined portion (see FIG. 3), an opening is formed in the base. The case where it is provided (see FIG. 4) has been described. Further, as a method of collecting an air flow between the lens holder and the recording medium, when the lens holder itself has a wall portion (see FIG. 5), when the base portion has a wall portion (see FIG. 7), The case of having a wall portion and further having a wall portion on the base (see FIG. 9) has been described. However, it is possible to configure a better application by appropriately combining the above-described methods as a method in which the lens holder obtains lift and a method in which an air flow is collected between the lens holder and the recording medium.

It is a figure which shows schematic structure of a disc reproducing | regenerating apparatus. It is the figure which showed schematic structure of the optical head shown in FIG. It is the figure which showed schematic structure of the other optical head. It is the figure which showed schematic structure of other optical head. It is the figure which showed schematic structure of other optical head. FIG. 6 is a top view and a cross-sectional view of the optical head shown in FIG. 5. It is the figure which showed schematic structure of other optical head. FIG. 8 is a top view and a cross-sectional view of the optical head shown in FIG. 7. It is the figure which showed schematic structure of other optical head. FIG. 10 is a top view and a cross-sectional view of the optical head shown in FIG. 9.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Disc reproducing device 3,100,101,102,103,104 Optical head 10 Objective lens 20,110,120,130 Lens holder 21 Convex part 30,31,33,36 Base 32 Opening part 34 3rd wall part 35 1st 4 wall portion 131 first wall portion 132 second wall portion 133 inclined portion

Claims (5)

A pickup lens that receives light from the disc;
A lens holder for holding the pickup lens;
A base for movably holding the lens holder;
A separation mechanism disposed in the lens holder that generates a force in a direction to separate the lens holder from the disk by an air flow generated by rotation of the disk;
A disc reproducing apparatus comprising:   The disc reproducing apparatus according to claim 1, wherein the separation mechanism is a convex portion or an inclined portion.   The disk reproducing apparatus according to claim 1, wherein the separation mechanism is an opening disposed in the base, and an air flow entering from the opening generates a force in a direction to separate the lens holder from the disk.   The disk reproducing apparatus according to claim 1, wherein an air flow control unit for collecting an air flow in the separation mechanism is provided in the lens holder.   The disk reproducing apparatus according to claim 1, wherein an air flow control unit for collecting an air flow in the separation mechanism is provided in the base.

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