JP2010102810A - Optical pickup device and optical disk device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduces the number of optical components in an optical pickup device which uses a light of two or more wavelengths. <P>SOLUTION: A first and second optical integrated elements 30 and 50, in each of which a light-emitting element and a light-receiving element are integrated into a single body, are used. Optical axes C1 and C2, through which laser beams of different wavelengths which are emitted from the first and second optical integrated elements 30 and 50 reach vertical deflection mirrors 71 and 72, are linear and not parallel to each other, and the optical integrated elements are arranged so that they are oblique to each other. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an optical pickup device and an optical disk device. Specifically, the present invention relates to an optical pickup device that guides light for recording and reproducing information signals to and from a disc-shaped recording medium mounted on a disc table, and an optical disc device including the same.

  Recording media such as CD (Compact Disc, registered trademark) and DVD (Digital Versatile Disc, registered trademark) have become widespread and widely used as means for recording and reproducing various information such as video information, music information, and document information. ing. CD (registered trademark) uses a laser having a wavelength of 780 nm and an optical system having a numerical aperture of 0.45, and DVD (registered trademark) uses a laser beam having a wavelength of 660 nm and an optical system having a numerical aperture of 0.6. . Furthermore, in order to meet the demand for recording and reproducing higher quality video information for a long time, the recording capacity is improved by using a blue-violet laser having a wavelength of 405 nm and an objective lens having a numerical aperture (NA) of 0.85. BD (Blu-ray Disc, registered trademark) is also widely used.

  An optical disc apparatus in which a drive device that records and reproduces recording media of different standards is built in one information recording / reproducing apparatus (for example, a notebook personal computer or an imaging device using a disc-shaped medium) has been commercialized. . When incorporated in a personal computer or the like, the overall size of the optical disk apparatus is limited, and it is required to record and reproduce the various recording media described above with a single optical pickup apparatus. Thus, for example, Patent Document 1 discloses an optical pickup device that can record and reproduce recording media of different standards in a constrained small space.

  FIG. 11 shows a schematic configuration diagram of the optical pickup device disclosed in FIG. As shown in FIG. 11, the optical pickup device is provided with a light source 101 that emits light with a blue wavelength (405 nm) and a light source 111 that emits light with two red wavelengths (660 nm and 780 nm). A polarization beam splitter 102, a half mirror 103, and a reflection mirror 126 are arranged along the optical axis 201 on the outgoing light path of the light source 101. The auxiliary lens 104, the collimating lens 105 driven by the collimating lens driving means 109, the quarter wavelength plate 106, and the rising mirror 107 are disposed on the reflection optical path of the half mirror 103, and the objective is positioned on the reflection optical path of the rising mirror 107. A lens 108 is disposed. A light receiving element 123 for monitoring is disposed on the reflection light path of the reflection mirror 126. A detector 110 that detects return light from the recording medium 131 is disposed on the reflected light path of the polarization beam splitter 102.

  Further, a half-wave plate 112, a wavelength selective diffraction element 113, a dichroic half mirror 114, and a condensing lens 129 and a light receiving element 123 are disposed on the transmitted light path on the outgoing light path of the light source 111. A collimating lens 115, a liquid crystal aberration correction element 116, a broadband quarter-wave plate 117, and a rising mirror 118 are arranged on the reflected light path of the dichroic half mirror 114, and the objective lens 119 is placed on the reflected light path of the rising mirror 118. Be placed. Further, a detector 122 is disposed via a detection lens 121 on an optical path through which return light from the recording medium 131 passes through the dichroic half mirror 114.

In the optical pickup device having the configuration shown in FIG. 11, in the optical pickup device that uses light of three wavelengths, one light-receiving element 123 for monitoring is commonly used for a light source of three wavelengths, thereby The size is reduced.
JP 2008-102997 A

  In the optical pickup device disclosed in Patent Document 1 described above, the optical path from the light source to the objective lens is bent halfway by a reflecting mirror in order to use the monitor light receiving element in common. For this reason, the number of parts will increase. In the case of the example shown in FIG. 11, the total number of optical components from the light source to the rising mirror is 19 points. In order to simplify the optical adjustment of each component and increase the reliability, it is preferable that the number of components is small. In order to suppress the occurrence of aberration, it is required to reduce the number of optical components as much as possible.

  In view of the above problems, an object of the present invention is to reduce the number of optical components and improve the reliability in an optical pickup device that uses light of two or more wavelengths.

  In order to solve the above problems, an optical pickup device according to the present invention includes a light emitting element holder that holds a light emitting element that emits laser light having a first wavelength, a light receiving element, and a laser beam emitted from the light emitting element. A first optical integrated element integrated with an optical element that guides the return light from the recording medium to the light receiving element, and a light emitting element holding that holds the light emitting element that emits the laser light of the second wavelength. A second optical integrated element in which a body, a light receiving element, an optical element for guiding laser light emitted from the light emitting element to the outside and guiding return light from the recording medium to the light receiving element are integrated; The first objective lens corresponding to the laser beam having the first wavelength and the second objective lens corresponding to the laser beam having the second wavelength are moved to predetermined positions with respect to the recording surface of the disc-shaped recording medium. Objective lens movement In addition, laser beams of different wavelengths emitted from the first and second optical integrated elements are respectively guided to the first and second objective lenses, and return light from the recording medium is supplied to the first and second lights. A first optical path that has a function of leading to the integrated elements and that is linear in the first and second optical integrated elements to the rising mirrors of the first and second objective lenses and is non-parallel. And a second optical system.

  An optical disk device according to the present invention includes a disk table on which a disk-shaped recording medium is mounted, and an optical pickup device mounted on a moving table that moves on the recording surface of the recording medium. The optical pickup device having the above-described configuration of the present invention is used as this optical pickup device.

As described above, in the optical pickup device of the present invention, the light emitting element holder, the light receiving element, and the optical system that guides the laser light emitted from the light emitting element to the outside and guides the return light from the recording medium to the light receiving element. First and second optical integrated elements integrated with the elements are used. These first and second optical integrated elements are provided corresponding to the first and second wavelengths. Furthermore, first and second optical systems are provided in which the optical path from the first and second optical integrated elements to the rising mirrors of the first and second objective lenses is linear and non-parallel. Shall.
With such a configuration, the number of optical components can be reduced, and the entire optical pickup device can be reduced in size.

  According to the present invention, it is possible to suppress an increase in the number of optical components while using light of two or more wavelengths in an optical pickup device.

Examples of the best mode for carrying out the present invention will be described below, but the present invention is not limited to the following examples. This will be described in the following order.
[1] Embodiment of optical disk device [2] Embodiment of optical pickup device 1. Structure of objective lens driving device 2. Configuration of optical system from light emitting element (optical integrated element) to objective lens Configuration of optical integrated device

[1] Embodiment of Optical Disc Device FIG. 1 shows a schematic configuration diagram of an optical disc device according to an embodiment of the present invention. As shown in FIG. 1, in the optical disk apparatus 1 according to the present embodiment, required members and mechanisms are arranged in an outer casing 2, and a disk insertion slot (not shown) is formed in the outer casing 2. A chassis (not shown) is disposed in the outer casing 2, and the disk table 3 is fixed to the motor shaft of a spindle motor attached to the chassis.

  Parallel guide shafts 4a and 4b are attached to the chassis, and a lead screw 5 that is rotated by a feed motor (not shown) is supported. The optical pickup device 6 includes a moving base 7, required optical components provided on the moving base 7, and an objective lens driving device 8 disposed on the moving base 7, and is provided at both ends of the moving base 7. The bearing portions 7a and 7b are slidably supported by the guide shafts 4a and 4b, respectively. When a nut member (not shown) provided on the moving base 7 is screwed into the lead screw 5 and the lead screw 5 is rotated by the feed motor, the nut member is fed in a direction corresponding to the rotation direction of the lead screw 5. As a result, the optical pickup device 6 is moved in the radial direction (radial direction) of the disc-shaped recording medium 100 mounted on the disc table 3.

[2] Embodiment of optical pickup device Next, the configuration of the objective lens driving device 8 of the optical pickup device 6 provided in the optical disk device 1 described above will be described. FIG. 2 is a schematic perspective configuration diagram of the objective lens driving device 8 according to the present embodiment. FIGS. 3 and 4 show schematic perspective configuration diagrams of the movable block 10.

In the objective lens driving device 8, as shown in FIG. 2, a fixed block 9 and a movable block 10 operated with respect to the fixed block 9 are arranged on the moving base 7. The fixed block 9 is fixed to the moving base 7, and the circuit board 11 is attached to the rear surface.
As shown in FIG. 3, the movable block 10 is configured by attaching necessary parts to a lens holder 12. A coil mounting groove 12a is formed on the entire circumference near the upper end of the lens holder 12. A substantially rectangular tube-shaped first focus coil 13 is attached to the coil attachment groove 12a, and the axial direction of the first focus coil 13 is the focus direction (vertical direction). The first focusing coil 13 is provided as a first thrust generating portion 13a and a second thrust generating portion 13b whose front and rear portions extend in the left-right direction.

  As shown in FIG. 4, the lens holder 12 is formed with an optical path opening 12 b opened forward. The upper surface of the lens holder 12 is formed as a lens attachment portion 12c, and the objective lenses 14 and 15 are attached to and held by the lens attachment portion 12c. The objective lenses 14 and 15 are spaced apart in the left-right direction (radial direction). It is provided corresponding to different types of recording media 100, for example, a recording medium having a use wavelength of laser light of around 780 nm, a recording medium having a use wavelength of around 660 nm, a recording medium having a use wavelength of around 405 nm, and the like.

  Upright mirrors (not shown) are arranged below the objective lenses 14 and 15, respectively. The upright mirror has a function of bending laser light emitted from a light source, which will be described later, and incident through the optical path opening 12b, to be incident on the objective lenses 14 and 15, respectively.

The rear surface of the lens holder 12 is formed as a coil attachment portion 12d.
A second focus coil 16 and tracking coils 17 and 17 are provided in 2d. The tracking coils 17 and 17 are disposed on both the left and right sides of the second focusing coil 16, respectively. These second focusing coil 16 and tracking coils 17 and 17 are all formed in a substantially rectangular tube shape, and are attached to the coil attachment portion 12d in such a direction that the axial direction is the tangential direction. A pair of tilt coils (not shown) is attached to the lens holder 12.

  Connection boards 18 and 18 are attached to the left and right ends of the coil attachment portion 12d of the lens holder 12, respectively. The respective terminals of the first focus coil 13, the second focus coil 16, the tracking coils 17, 17 and the tilt coil are connected to the connection terminals of the connection boards 18, 18, respectively. As shown in FIG. 2, the front ends of the support springs 19, 19,... Are joined to the connection boards 18 and 18 by, for example, soldering. The support springs 19, 19,... Are made of, for example, a wire shape with a conductive metal material.

The rear ends of the support springs 19, 19,... Are joined to the circuit board 11 attached to the fixed block 9, for example, by soldering.
As described above, both ends of the support springs 19, 19,... Are joined to the connection substrates 18, 18 of the movable block 10 and the circuit board 11 of the fixed block 9, so that the movable block 10 is supported by the support springs 19, 19. Are connected to the fixed block 9 and held hollow.

  In the objective lens driving device 8, the first focus coil 13 and the second focus are supplied from a power supply circuit (not shown) through the circuit board 11, the support springs 19, 19,. A drive current is supplied to the working coil 16. Similarly, a drive current is supplied to the tracking coils 17 and 17 and the tilt coil.

  A horizontally long first focusing magnet 20 is disposed on the front side of the movable block 10 (see FIGS. 2 to 4). The first focusing magnet 20 is attached to, for example, a mounting portion (not shown) of the moving base 7 and is disposed on the upper side of the optical path opening 12b and in front of the first thrust generating portion 13a of the first focusing coil 13. The

  A yoke member 21 made of a magnetic metal material is disposed on the moving base 7 (see FIG. 2). The yoke member 21 has a base portion 21a facing upward and downward, and a yoke portion 21b protruding upward from the base portion 21a. A second focus magnet 22 and tracking magnets 23 and 23 are attached to the front surface of the yoke portion 21b. A tilt magnet (not shown) is attached to the yoke member 21.

  The yoke member 21 may have a base portion 21a and a yoke portion 21b that are configured as separate parts. In this case, for example, the base portion 21a has a function of fixing the fixed block 9 to the moving base 7 and holding the yoke portion 21b, and the yoke portion 21b is configured to have a function as a dedicated yoke. It is possible.

  The second focusing magnet 22 is disposed to face the second thrust generating portion 13b of the first focusing coil 13. The tracking magnets 23 and 23 are disposed to face the tracking coils 17 and 17, respectively, and the tilt magnets are respectively disposed to face the tilt coil.

  The objective lens driving device 8 may have a configuration in which a dedicated tilt magnet is not provided. For example, the second focus magnet 22 may also be used as a tilt magnet. In this case, the tilt coil is disposed to face the second focus magnet 22 that also serves as the tilt magnet.

  The first focusing coil 13, the second focusing coil 16, the first focusing magnet 20, the second focusing magnet 22, and the yoke member 21 constitute a focusing magnetic circuit. The tracking coils 17 and 17, the tracking magnets 23 and 23, and the yoke member 21 constitute a tracking magnetic circuit. Further, the tilting magnetic circuit is configured by the tilting coil, the tilting magnet, and the yoke member 21.

  A drive current is supplied from a power supply circuit (not shown) to the first focus coil 13, the second focus coil 16, the tracking coils 17, 17 or the tilt coil. Then, the force (thrust force) of the direction according to the direction of these drive currents and the direction of the magnetic flux generated by the first focus magnet 20, the second focus magnet 22, the tracking magnets 23, 23, or the tilt magnet. ) Occurs. The movable block 10 is moved or tilted in the focus direction, tracking direction, or tilt direction. When the movable block 10 is moved in the focus direction, the tracking direction, or the tilt direction, the support springs 19, 19,.

  The focus direction is the direction of moving away from or in contact with the recording medium 100 (F direction shown in FIG. 2), that is, the vertical direction, and the tracking direction is the radial direction of the recording medium 100 (TR direction shown in FIG. 2). The tilt direction is a direction around the axis (TI direction shown in FIG. 2) extending in a direction (tangential direction) perpendicular to both the focus direction and the tracking direction.

  In the focus operation described above, when a drive current is supplied from the power supply circuit to the first focus coil 13, the first and second thrust generators 13a and 13b of the first focus coil 13 are movable blocks. Thrust is generated to move 10 in the focus direction. Further, when a drive current is supplied from the power supply circuit to the second focus coil 16, a thrust force that causes the second focus coil 16 to move the movable block 10 in the focus direction is generated.

  In the optical disc apparatus 1 having the above configuration, when the disc table 3 is rotated in accordance with the rotation of the spindle motor, the disc-shaped recording medium 100 mounted on the disc table 3 is rotated. At the same time, the optical pickup device 6 is moved in the radial direction of the recording medium 100, and a recording operation or a reproducing operation is performed on the recording medium 100.

  In this recording operation and reproducing operation, when a driving current is supplied to the first focusing coil 13 and the second focusing coil 16, the movable block 10 of the objective lens driving device 8 is moved to the fixed block 9 as described above. On the other hand, it is operated in the focus direction FF shown in FIG. Thereby, focus adjustment is performed so that the spot of the laser light irradiated through the objective lenses 14 and 15 is condensed on the recording surface of the recording medium 100.

  When a drive current is supplied to the tracking coils 17 and 17, as described above, the movable block 10 of the objective lens driving device 8 is operated in the tracking direction TR-TR shown in FIG. The Thus, tracking adjustment is performed so that the spot of the laser light irradiated through the objective lenses 14 and 15 is condensed on the recording track of the recording medium 100.

  Further, when a drive current is supplied to the tilt coil, the movable block 10 of the objective lens drive device 8 is operated in the tilt direction TI-TI shown in FIG. Thereby, the tilt adjustment is performed so that the optical axis of the laser light irradiated through the objective lenses 14 and 15 is perpendicular to the recording surface of the recording medium 100.

In the example illustrated in FIGS. 1 to 4, the example in which the first focusing coil 13 is disposed in a horizontal state is shown, but the present invention is not limited to this. For example, the focus adjustment, tracking adjustment, and tilt adjustment mechanisms such as arranging the first focus coil 13A in an inclined state are not limited to the above-described examples, and various modifications can be made. It is. For example, by supplying a drive current in the opposite direction to the first focus coil 13 and the second focus coil 16, the focus magnetic circuit can also be used as a tilt magnetic circuit. It is. In this case, the movable block 10 is moved in the tilt direction TI-TI shown in FIG.
In addition, the focus direction has been described as the vertical direction, the tracking direction as the left-right direction, and the tangential direction as the front-rear direction. However, these directions are shown as examples for convenience of explanation, and are particularly limited to these directions. There is no.

  In the optical pickup device 6 having the configuration described above, the first focus coil 13 and the second focus coil 16 are provided. The first focusing coil 13 is attached to the lens holder 12 with the first thrust generating portion 13a and the second thrust generating portion 13b positioned in the front-rear direction. Furthermore, since the second focusing coil 16 is attached to the lens holder 12 with the axial direction being the tangential direction, a large opening area of the optical path opening 12b of the lens holder 12 can be secured. In addition, since the focusing coil is not attached to the front surface of the lens holder 12, the movable block 10 can be thinned, and a large thrust necessary for the focusing operation can be secured while ensuring the thinning.

Further, since the focusing coil is not attached to the front surface of the lens holder 12, the movable block 10 can be downsized in the tangential direction, and high high-order resonance characteristics can be ensured.
Further, the movable block 10 becomes lighter by making the movable block 10 thinner, and the sensitivity in the focus operation, tracking operation, and tilt operation can be improved.
In addition, in the objective lens driving device 8, since the first focus coil 13 is arranged at a position surrounding the two objective lenses 14 and 15, a stable focus operation can be realized and the focus can be achieved. Large thrust necessary for operation can be secured.

2. Configuration of optical system from light emitting element (optical integrated element) to objective lens Next, a configuration of an optical system from the light emitting element (specifically, an optical integrated element including the light emitting element) to the objective lens, which is a feature of the present invention. Will be explained. In the following description, the schematic plan configuration diagram of FIGS. 5 to 7 and the schematic perspective configuration diagram of FIG. 8 are referred to. FIG. 5 schematically shows the above-described objective lens driving device 8 disposed on the moving base 7 and the first optical system 81 and the second optical system 82 that constitute the optical path from the light emitting element to the objective lenses 14 and 15. FIG. 6 is a plan configuration diagram illustrating a state in which the objective lens driving device 8 is removed from FIG. 5, and FIG. 7 is a schematic plan configuration diagram viewed from the back side of the moving base 7 illustrated in FIG. 5 to 7, parts corresponding to those described in FIGS. 1 to 4 are denoted by the same reference numerals, and redundant description is omitted.

  As shown in FIGS. 5 to 7, in this example, rising mirrors 71 and 72 (see FIGS. 6 and 7) provided from the first and second optical integrated elements 30 and 50 below the objective lenses 14 and 15. Each optical component is arranged so that the optical path leading to (see) is linear and non-parallel. That is, the optical axis C1 of the first optical system 81 and the optical axis C2 of the second optical system 82 are each configured as a straight line, and each is in the tangential direction (indicated by an arrow TI) of a recording medium (not shown). Direction). In this example, the first optical system 81 is the inner peripheral side, and the second optical system 82 is the outer peripheral side. In the first optical system 81, the first integrated optical element 30 including the light emitting element that is a light source is arranged on the radially inner side from the arrangement position of the objective lens 15. In the second optical system 82, the second optical integrated element 50 is arranged on the outer peripheral side with respect to the arrangement position of the objective lens 14. The angle formed by the optical axes C1 and C2 of the optical systems 81 and 82 and the tangential direction TI may be appropriately selected from the size of each optical component, the distance between the optical components, the shape and dimensions of the moving base 7, and the like. For example, the whole can be efficiently arranged in a smaller size by setting the range to about 10 ° to 20 °. In the example shown in the figure, a case where the angle between the optical axes C1 and C2 and the tangential direction TI is about 14 ° to 16 ° is shown.

  The optical parts constituting the first and second optical systems 81 and 82 will be described with reference to FIGS. In this example, the optical components from the first optical integrated element 30 to the rising mirror 71 of the objective lens 15 are arranged in a straight line, for example, on the inner peripheral side of the recording medium (not shown), that is, in the radial direction (arrow TR (The direction indicated by). The light emitting section of the first optical integrated device 30 is provided with a member having a light separation function such as a beam splitter (details will be described later), and a monitoring light receiving element 40 is disposed on one emitting side. . On the other exit side, a coupling lens 41, an aberration correction element 42 including a liquid crystal element, a quarter wavelength plate 43, a collimator lens 44, and a rising mirror 71 are arranged.

  Similarly, in the second optical integrated device 50, a member having a light separation function is provided in the light emitting portion, and a light receiving element 60 for monitoring is disposed on one emitting side. A quarter-wave plate 61, a coupling lens 62, a collimator lens 63, and a rising mirror 72 are disposed on the other emission side. In this example, as shown in FIGS. 5 to 7, a collimator lens driving mechanism 66 that moves the collimator lens 63 is provided on the outer peripheral side of the second optical system 82, and the collimator lens 63 is moved, thereby moving the collimator lens 63. A configuration in which aberration correction is performed. Although the function of each of these optical components will be described later, the optical system used in the optical pickup device of the present invention is not limited to the above example, and can be replaced with an optical element having other functions. For example, an aberration correction element may be used in place of the aberration correction function by the collimator lens driving mechanism 66, and various other modifications are possible.

3. Next, the configuration of the first and second optical integrated devices 30 and 50 will be described. 9 and 10 are schematic cross-sectional configuration diagrams of the first and second optical integrated devices 30 and 50. As shown in FIG. 9 and FIG. 10, the light emitting portions 31 and 51 in the first and second optical integrated devices 30 and 50 include a light emitting device 31b made of a semiconductor laser and the like inside the light emitting device holders 31a and 51a. It is assumed that 51b is held. The light emitting element holders 31a and 51a are preferably made of resin, metal, or the like, and also have a function as a casing. With this configuration, the light emitting units 31 and 51 can be removed and replaced from the first and second optical integrated devices 30 and 50.

  Here, for example, as the first light emitting element 31b in the first optical integrated element 30, for example, a two-wavelength semiconductor laser element that emits light in two wavelength bands having a center wavelength of 780 nm and 660 nm can be used. As shown in FIG. 9, the light emitting unit 31 is fixed to one surface of the support substrate 33 with an adhesive or the like. On the other surface of the support substrate 33, a light receiving element 35 is provided, and an auxiliary plate 34 made of resin or metal is fixed. Furthermore, a second optical unit 37 having the above-described beam splitter function is fixed thereon via a first optical unit 36 having a function such as a hologram or a cylindrical lens (not shown). The second optical unit 37 is formed by bonding optical members having optical transparency through optical functional thin films, and the optical functional thin films 37a and 37b are, for example, 45 ° with respect to the optical axis C1. Is done. The optical functional thin film 37a is, for example, a polarization beam splitter, and the optical functional thin film 37b is, for example, a reflective film.

  In such a configuration, light having a predetermined polarization direction out of the light emitted from the light emitting element 31b passes through the optical functional thin film 37a formed of a polarization beam splitter and is led out along the optical axis C1. On the other hand, light having a polarization direction orthogonal to the polarization direction is reflected by the optical functional thin film 37a and emitted forward (to the left in FIG. 9). Thereby, a part of the light emitted from the light emitting element 31b is made incident on the light receiving element 40 for monitoring shown in FIGS.

The light derived from the first integrated optical element 30 along the optical axis C1 is incident on the aberration correction element 42 via the coupling lens 41 as shown in FIGS. The light whose aberration has been corrected is incident on the rising mirror 71 via the quarter-wave plate 43 and the collimator lens 44, and is incident on the objective lens 15 after being bent, for example, by 90 ° (see FIG. 5). . The light condensed on the recording surface of the recording medium by the objective lens 15 and reflected by the recording surface is again the objective lens 15, the rising mirror 71, the collimator lens 44, the quarter wavelength plate 43, the aberration correction element 42, the cup. The light enters the first integrated optical element 30 through the ring lens 41. Since the polarization direction of the light that has passed through the quarter-wave plate 43 is rotated by 90 °, the return light is reflected by the optical functional thin film 37a and transmitted through the third optical unit 37 along the optical axis C11. To do. Then, it is reflected by the optical functional thin film 37 b, passes through the first optical unit 36 along the optical axis C <b> 12, and enters the light receiving element 35 provided on the support substrate 33.
The laser light emitted from the light emitting element 31b as described above is incident on the light receiving element 40 for monitoring and the light receiving element 35 for focus control and tracking control signal detection, and for reproducing the recording signal.

  Further, as the second light emitting element 51b in the second optical integrated element 50, for example, a semiconductor laser element that emits light in a single wavelength band with a central wavelength of 405 nm can be used. As shown in FIG. 10, the light emitting unit 51 is fixed to one surface of the support substrate 53 with an adhesive or the like. On the other surface of the support substrate 53, a light receiving element 55 is provided, and an auxiliary plate 54 made of resin or metal is fixed. Further thereon, a second optical unit 57 having the above-described beam splitter function is fixed via a first optical unit 56 having a function such as a hologram or a cylindrical lens (not shown). The second optical unit 57 is formed by bonding optical members having optical transparency through optical functional thin films, and the optical functional thin films 57a and 57b are, for example, 45 ° with respect to the optical axis C2. Is done. The optical functional thin film 57a is also a polarization beam splitter, for example, and the optical functional thin film 57b is a reflection film, for example.

  In such a configuration, light in a predetermined polarization direction out of the light emitted from the light emitting element 51b passes through the optical functional thin film 57a formed of a polarization beam splitter and is led out along the optical axis C2. On the other hand, light having a polarization direction orthogonal to the polarization direction is reflected by the optical functional thin film 57a and emitted forward (leftward in FIG. 10). Thereby, a part of the light emitted from the light emitting element 51b is made incident on the light receiving element 60 for monitoring shown in FIGS.

The light derived from the integrated optical device 50 along the optical axis C2 is incident on the rising mirror 72 via the collimator lens 63 via the wave plate 61 and the coupling lens 62, as shown in FIGS. Is done. Then, for example, the optical path is bent by 90 ° and incident on the objective lens 14 (see FIG. 5). The light that is condensed on the recording surface of the recording medium by the objective lens 14 and reflected by the recording surface again passes through the objective lens 14, the raising mirror 72, the collimator lens 63, the coupling lens 62, and the wavelength plate 61. Is incident on the optical integrated device 50. Since the polarization direction of the light that has passed through the quarter-wave plate 61 is rotated by 90 °, the return light is reflected by the optical functional thin film 57a and transmitted through the second optical unit 57 along the optical axis C21. To do. Then, it is reflected by the optical functional thin film 57 b, passes through the first optical unit 56 along the optical axis C <b> 22, and enters the light receiving element 55 provided on the support substrate 53.
The laser light emitted from the light emitting element 51b is incident on the light receiving element 60 for monitoring and the light receiving element 55 for focus control and tracking control signal detection, and for reproducing the recording signal.

  In the above-described example, the example in which two optical functional thin films are provided in the third optical units 37 and 57 in the first and second optical integrated devices 30 and 50, respectively, is shown. May be 2 or more. For example, an optical integrated device that emits and receives two wavelengths of light may have various configurations such as providing a wavelength selection film or providing a hologram for the purpose of signal separation. Further, for example, between the support substrate 33 and the first optical unit 36 in the first optical integrated device 30 and between the support substrate 53 and the first optical unit 56 in the second optical integrated device 50, Similarly, various modifications and changes such as interposing an optical functional element such as a hologram and a grating are possible.

  As described above, in the first and second optical integrated devices 30 and 50, the optical component as a whole is obtained by using the optical component in which the light emitting element 31b and the light receiving element 35, the light emitting element 51b and the light receiving element 55 are integrated. The number of parts can be reduced. For example, in the optical pickup device disclosed in Patent Document 1 described with reference to FIG. 11, the number of optical components arranged in the optical path from the light source to the objective lens has increased to 20 points. On the other hand, in the above-described embodiment, the number of optical components can be reduced to 11 although the monitoring light receiving element is not shared. Since the number of parts can be remarkably reduced in this way, it is possible to greatly simplify the work of optically adjusting each optical part and improve the reliability. As a result, productivity can be improved and costs can be reduced.

As shown in FIGS. 9 and 10, assuming that the lengths of the first and second optical integrated devices 30 and 50 in the direction orthogonal to the optical axes C1 and C2 are L1 and L4, L1 = L4 = 1.11. It was possible to suppress to 7 mm. Further, assuming that the lengths in the optical axis direction excluding the light emitting parts 31 and 51 are L2 and L5, respectively, and the lengths in the optical axis direction of the light emitting parts 31 and 51 (excluding the terminals) are L3 and L6, L2 = 5. 7 mm, L3 = 3.9 mm, L5 = 6.1 mm, and L6 = 2.7 mm.
By using the first and second optical integrated elements 30 and 50 having these dimensions, the optical pickup device 6 having the arrangement shown in FIGS. 5 to 8 can be miniaturized. Specifically, the dimension from the optical axis center position of the objective lens 15 corresponding to the light in the red band to the outer peripheral side end of the moving base 7 could be 18 mm or less. In addition, the distance between the guide shafts 4a and 4b shown in FIG. 1 that supports the moving base can be reduced to 45 mm or less, and the entire apparatus can be downsized compared to the conventional apparatus.

  The specific shapes and structures of the respective parts shown in the best mode for carrying out the invention described above are merely examples of the implementation of the present invention, and the present invention is thereby limited. This technical scope should not be interpreted in a limited way.

1 is a schematic perspective view of an embodiment of an optical disk device of the present invention. It is an expansion perspective view of the objective lens drive device in the embodiment of the optical pickup device of the present invention. It is an expansion perspective view of the movable block in the embodiment of the optical pickup device of the present invention. It is an expansion perspective view which shows the movable block in the embodiment of the optical pick-up apparatus of this invention in the state seen from the direction different from FIG. It is a schematic plane block diagram in the embodiment of the optical pickup device of the present invention. FIG. 6 is a schematic plan configuration diagram in a state where an objective lens driving device is removed in the example shown in FIG. 5. FIG. 6 is a schematic plan configuration view seen from the back side in the example shown in FIG. 5. 1 is a schematic perspective configuration diagram of a main part in an embodiment of an optical pickup device of the present invention. It is a schematic sectional block diagram of the optical integrated element in the embodiment of the optical pick-up apparatus of this invention. It is a schematic sectional block diagram of the optical integrated element in the embodiment of the optical pick-up apparatus of this invention. It is a schematic plane block diagram of an example of the conventional optical pick-up apparatus.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Optical disk apparatus, 3 ... Disk table, 6 ... Optical pick-up apparatus, 7 ... Moving base, 8 ... Objective lens drive device, 9 ... Fixed block, 10 ... Movable block, 12 ... Lens holder, 12b ... Optical path opening, 13 DESCRIPTION OF SYMBOLS 1st coil for focusing, 13a ... 1st thrust generation part, 13b ... 2nd thrust generation part, 14 ... Objective lens, 15 ... Objective lens, 16 ... 2nd focusing coil, 17 ... Tracking coil , 19 ... support spring, 20 ... first focus magnet, 22 ... second focus magnet, 23 ... tracking magnet, 30 ... first integrated optical element, 31, 51 ... light emitting section, 31a, 51a ... Light emitting element holder, 31b, 51b ... Light emitting element, 33, 53 ... Support substrate, 34, 54 ... Auxiliary plate, 35, 55 ... Light receiving element, 36, 56 ... No. , 37, 57 ... second optical part, 37a, 37b, 57a, 57b ... optical functional thin film, 40, 60 ... light receiving element, 41, 62 ... coupling lens, 42 ... aberration correction element, 43, 61 ... Wave plate, 44, 63 ... Collimator lens, 50 ... Second optical integrated element, 66 ... Collimator lens driving mechanism, 71, 72 ... Rising mirror, 81 ... First optical system, 82 ... Second optical system 100 recording medium

Claims (6)

A light emitting element holding body that holds a light emitting element that emits a laser beam having a first wavelength, a light receiving element, and a laser beam emitted from the light emitting element is led out to the outside, and return light from a recording medium is received by the light receiving element. A first integrated optical element integrated with an optical element leading to the element;
A light emitting element holder that holds a light emitting element that emits laser light of a second wavelength, a light receiving element, and a laser beam emitted from the light emitting element is led out to the outside, and return light from a recording medium is received by the light receiving element. A second integrated optical element integrated with an optical element leading to the element;
The first objective lens corresponding to the laser beam having the first wavelength and the second objective lens corresponding to the laser beam having the second wavelength are placed at predetermined positions with respect to the recording surface of the disc-shaped recording medium. An objective lens moving mechanism having a moving mechanism;
Laser beams of different wavelengths emitted from the first and second optical integrated elements are respectively guided to the first and second objective lenses, and return light from the recording medium is guided to the first and second objective lenses. The optical path from the first and second optical integrated elements to the rising mirrors of the first and second objective lenses is linear and non-parallel. An optical pickup device comprising: first and second optical systems.   2. The optical pickup device according to claim 1, wherein the second optical integrated element includes a light emitting element that emits laser light having a second wavelength and a light emitting element that emits laser light having a third wavelength. The first wavelength is a wavelength of a blue band;
The optical pickup device according to claim 1, wherein the second wavelength is a wavelength in a red band. The first wavelength is a wavelength of a blue band;
The optical pickup device according to claim 2, wherein the second and third wavelengths are wavelengths in a red band. The optical element in the first and second optical integrated elements is an optical prism having a polarization beam splitter,
The optical pickup device according to claim 1, wherein a light receiving element for monitoring that receives at least a part of light emitted from the light emitting element is disposed on a reflection side of the polarizing beam splitter of the optical prism. A disk table on which a disk-shaped recording medium is mounted;
An optical pickup device mounted on a moving table that moves on the recording surface of the recording medium,
The optical pickup device is:
A light emitting element holding body that holds a light emitting element that emits a laser beam having a first wavelength, a light receiving element, and a laser beam emitted from the light emitting element is led out to the outside, and return light from a recording medium is received by the light receiving element. A first integrated optical element integrated with an optical element leading to the element;
A light emitting element holder that holds a light emitting element that emits laser light of a second wavelength, a light receiving element, and a laser beam emitted from the light emitting element is led out to the outside, and return light from a recording medium is received by the light receiving element. A second integrated optical element integrated with an optical element leading to the element;
The first objective lens corresponding to the laser beam having the first wavelength and the second objective lens corresponding to the laser beam having the second wavelength are placed at predetermined positions with respect to the recording surface of the disc-shaped recording medium. An objective lens moving mechanism having a moving mechanism;
Laser beams of different wavelengths emitted from the first and second optical integrated elements are respectively guided to the first and second objective lenses, and return light from the recording medium is guided to the first and second objective lenses. Each of the optical paths has a function of leading to an optical integrated element, and the optical path from the first and second optical integrated elements to the rising mirrors of the first and second objective lenses is linear and non-parallel. An optical disc device comprising: a first optical system and a second optical system.

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