JP2008198258A - Optical pickup device and optical disk device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a compact and inexpensive optical pickup device having no optical path bending mirror, and provide an optical disk device. <P>SOLUTION: The optical pickup device 30 is provided with a rising mirror 6 for transmitting a part of a laser beam, and a light amount control photodetector 9 for detecting a laser beam transmitted through the rising mirror 6. A base 10 includes a through part 10a having a predetermined through area 10b. A light source 1 is disposed outside the through area 10b of the through part 10a, and an objective lens driving device 11 is disposed in the through area 10b of the through part 10a. An objective lens 7 is held on the through area 10b of the through area 10a by the objective lens driving device 11. The through part 10a has a beam part 10c crossing the through part 10a in an area below the objective lens 7, and the rising mirror 6 and the light amount control photodetector 9 are disposed in the beam part 10c. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an optical pickup device and an optical disk device mounted on an electronic device such as a personal computer or a notebook computer.

  Optical pickup devices have been reduced in size, thickness, and weight along with improved recording and playback performance. In addition, cost reductions with reduced manufacturing costs have been promoted.

  FIG. 9 is a diagram illustrating a configuration of an optical system of a conventional optical pickup device, and FIG. 10 is a diagram illustrating a configuration of the conventional optical pickup device. The optical pickup device 100 can perform recording and reproduction on both a DVD and a CD.

  The light source 101 emits a laser beam for DVD or a laser beam for CD toward the optical disc 109.

  The diffractive element 102 includes a diffraction grating that passes the laser beam for DVD as it is and separates the laser beam for CD into three laser beams so as to be used for tracking control. The integrated prism 103 has a plurality of inclined surfaces on which an optical functional film is formed. The integrated prism 103 allows the laser light emitted from the light source 101 to pass through the optical disc 109 almost as it is. The integrated prism 103 directs the laser beam reflected by the optical disk 109 to the signal photodetector 110 instead of the light source 101. Further, the integrated prism 103 separates the laser beam for DVD and the laser beam for CD, and the CD hologram beam 103a separates the laser beam for CD into light used for focus control and light used for tracking control.

  The collimating lens 104 converts laser light, which is divergent light emitted from the light source 101, into parallel light. The optical path bending mirror 105 reflects the laser beam in a plane substantially parallel to the optical disc 109 to bend the optical path, thereby reducing the overall size of the optical pickup device 100. Further, the optical path bending mirror 105 transmits a part of the laser light so as to enter the light amount control photodetector 111 which is a detecting means for controlling the light amount of the light source. The rising prism 106 is disposed on the opposite side of the optical disk 109 with the objective lens 108 interposed therebetween, and raises the laser beam substantially parallel to the optical disk 109 at a substantially right angle.

  The hologram element 107 includes a quarter wavelength plate 107a and a DVD hologram 107b. The quarter-wave plate 107a converts linearly polarized laser light emitted from the light source 101 into circularly polarized laser light. Then, the circularly polarized laser beam reflected by the optical disk 109 is converted into linearly polarized light shifted by 90 ° from the forward laser beam. The DVD hologram 107b acts on the DVD laser light reflected by the optical disk 109, and separates the light used for focus control and the light used for tracking control. The objective lens 108 focuses the laser light emitted from the light source 101 and converted into parallel light by the collimator lens 104 onto the optical disk 109.

  The signal photodetector 110 detects the laser beam emitted from the light source 101 and reflected by the optical disk 109, converts it into an electrical signal and outputs it for use in an RF signal, a focus control signal, a tracking control signal, etc. To do. The light quantity control light detector 111 detects the laser light emitted from the light source 101, converts it into an electrical signal so as to be used for controlling the output of the light source 101, and outputs it.

  In the optical pickup device 100, the light source 101, the diffraction element 102, the integrated prism 103, and the signal photodetector 110 are integrated as a laser module and fixed to the base 112. The collimating lens 104, the optical path bending mirror 105, the rising prism 106, and the light amount control photodetector 111 are fixed to the base 112 directly or via an attachment member. The objective lens 108 and the hologram element 107 are incorporated in the objective lens driving device 113, and the objective lens driving device 113 is fixed to the base 112.

In Patent Document 1, the optical path bending mirror 105 is omitted, the rising prism 106 is used as a rising mirror, and the light amount control photodetector 111 is disposed on the opposite side of the light source 101 with the rising mirror interposed therebetween. The optical system of the device is shown.
Japanese Patent Laid-Open No. 2004-327012

  However, when the optical pickup device is to be manufactured in a small size and at a low cost, it is possible to eliminate the optical path bending mirror and to make the optical path one straight line without folding the optical path as in the configuration of the optical system of (Patent Document 1). There are two ways. In the optical system of (Patent Document 1), it is described that the light quantity control photodetector is arranged on the opposite side of the light source with the rising mirror interposed therebetween. The light quantity control photodetector needs to stably detect the laser light from the light source, and for that purpose, it is desirable to be fixed to the base. However, in the actual configuration, the rising mirror is disposed adjacent to the objective lens driving device on the opposite side of the optical disk with the objective lens interposed therebetween, and it is difficult to arrange the light quantity control photodetector in the mirror. Is accompanied.

  SUMMARY OF THE INVENTION An object of the present invention is to solve the above-described problems, and to provide a small and inexpensive optical pickup device and optical disc device that can be formed without an optical path bending mirror.

  In order to solve the above problems, the present invention provides a light source of laser light, an objective lens that focuses the laser light on an optical disc, drive means for driving the objective lens relative to the optical disc, and a direction of the laser light. Rising toward the objective lens and transmitting a part of the laser light, detection means for detecting the laser light transmitted through the rising mirror to control the amount of light of the light source, and the light source A base on which the objective lens, the driving unit, the rising mirror, and the detection unit are arranged, the base including a through portion having a predetermined through region, and the light source includes the through portion The drive means is arranged in the penetration area of the penetration part, the objective lens is held on the penetration area of the penetration part by the drive means, and the penetration means Parts, it said has a beam portion traversing the through portion at the lower area of the objective lens, the rising mirror and said detecting means is a optical pickup apparatus characterized by being arranged on the beam portion.

  The drive means is placed in the penetrating area of the penetrating part, a beam part that crosses the penetrating part is provided, and the rising mirror and the detecting means are fixed to the beam part. The means can be arranged. For this reason, in the actual configuration, it is possible to dispose the optical path bending mirror and to arrange a light amount control photodetector as detection means.

  Since the optical path bending mirror can be eliminated, the optical pickup device can be made small and inexpensive.

  According to the first aspect of the present invention, there is provided a laser light source, an objective lens for focusing the laser light on the optical disc, a driving means for driving the objective lens relative to the optical disc, and a direction of the laser light directed toward the objective lens. A rising mirror that transmits a part of the laser light while changing, a detection means that detects the laser light transmitted through the rising mirror to control the light amount of the light source, a light source, an objective lens, a driving means, a rising mirror, And a base on which the detecting means is arranged, the base has a through portion having a predetermined through area, the light source is arranged outside the through area of the through section, and the driving means is in the through area of the through section. The objective lens is held on the penetrating region of the penetrating portion by the driving means, the penetrating portion has a beam portion that crosses the penetrating portion in the lower region of the objective lens, and the rising mirror and the detecting means are the beam portion. Placed in And it has an optical pickup device.

  The drive means is placed in the penetrating area of the penetrating part, a beam part that crosses the penetrating part is provided, and the rising mirror and the detecting means are fixed to the beam part. The means can be arranged. Therefore, in the actual configuration, it is possible to dispose the optical path bending mirror and to arrange a light quantity control photodetector as detection means. Therefore, the optical pickup device can be made small and inexpensive.

  Further, since the beam portion crosses the penetration portion, the rigidity of the base can be increased. Therefore, the base can be made thin, and the optical pickup device can be made thin.

  According to a second aspect of the present invention, in the first aspect of the present invention, the beam portion has an extension piece extending in the vertical direction from the central portion to the light source side, and has a mounting portion for the detection means at the central portion. This is an optical pickup device having a rising mirror mounting portion at the tip of a piece.

  Since the detection means and the raising mirror can be attached to one beam portion, space can be saved and the optical pickup device can be made smaller.

  According to a third aspect of the present invention, in the first aspect of the present invention, the driving means includes a holder that fixes the objective lens, an elastic member that elastically supports the holder at one end, and a holding member that holds the other end of the elastic member. The detecting means is an optical pickup device disposed between the raising mirror and the holding member.

  It is not necessary to provide a space for arranging the detection means outside the drive means, so that the space for arranging the detection means can be saved, and the optical pickup device can be made compact.

  A fourth aspect of the present invention is the optical pickup device according to the first aspect of the present invention, wherein the surface of the detecting means for detecting the laser beam is substantially perpendicular to the optical disc.

  The dimension of the optical pickup device in the thickness direction can be suppressed, and the optical pickup device can be made thin.

  According to a fifth aspect of the present invention, in the first aspect of the present invention, the collimating lens is provided on the optical path between the light source and the rising mirror to make the laser light substantially parallel, and the detecting means is a laser that is parallel light. This is an optical pickup device into which light is incident.

  The laser light that has been collimated by the collimator lens and transmitted through the rising mirror enters the detection means without passing through the condenser lens. Since there is no condenser lens, the optical pickup device can be made inexpensive.

  The invention of claim 6 is the invention of claim 3, further comprising a flexible printed circuit board connected to the detecting means from the outside of the penetrating part, the flexible printed circuit board being connected via the beam part, This is an optical pickup device disposed between the surface of the beam portion on the optical disc side and the elastic member.

  Since the flexible printed circuit board is connected to the detection means from the outside of the penetrating part without passing through the holding member portion of the driving means, the optical pickup device can be made thin.

  The invention of claim 7 is the invention of claim 6, wherein the beam portion has a slit, and the flexible printed circuit board is restricted from moving in a direction perpendicular to the optical disk by inserting the end of the flexible printed circuit board into the slit. This is an optical pickup device.

  Since the possibility that the flexible printed circuit board moves and comes into contact with the elastic member is reduced, the reliability of the optical pickup device can be increased.

  The invention of claim 8 is the optical pickup device according to claim 1, wherein the transmittance of the rising mirror for transmitting the laser beam is 4% or more and 8% or less.

  Since the amount of laser light incident on the detection means can be increased, the condenser lens can be eliminated.

  A ninth aspect of the present invention is the optical pickup device according to the first aspect of the present invention, wherein the light source, the rising mirror, and the detecting means are arranged on substantially one straight line.

  Since the optical path is bent by the optical path bending mirror, there is an unnecessary space in the optical pickup device, which can be removed.

  According to a tenth aspect of the present invention, there is provided a laser light source, an objective lens for focusing the laser light on the optical disk, a driving means for driving the objective lens with respect to the optical disk, and changing the direction of the laser light toward the objective lens and the laser. Rising mirror that transmits part of light, detection means for detecting laser light that has passed through the raising mirror to control the light quantity of the light source, light source, objective lens, driving means, raising mirror, and detection means A base having a penetrating portion having a predetermined penetrating region, the light source being disposed outside the penetrating region of the penetrating portion, and the driving means being disposed in the penetrating region of the penetrating portion. The objective lens is held on the penetrating region of the penetrating portion by the driving means, the penetrating portion has a beam portion that crosses the penetrating portion in the lower region of the objective lens, and the rising mirror and the detecting means are arranged on the beam portion. Have An optical disk apparatus.

  The drive means is placed in the penetrating area of the penetrating part, a beam part that crosses the penetrating part is provided, and the rising mirror and the detecting means are fixed to the beam part. The means can be arranged. For this reason, in the actual configuration, it is possible to dispose the optical path bending mirror and to arrange a light amount control photodetector as detection means. Therefore, the optical disk device can be made small and inexpensive.

  Further, since the beam portion crosses the penetration portion, the rigidity of the base can be increased. Therefore, the base can be made thin, and the optical disk device can be made thin.

(Embodiment 1)
The first embodiment will be described with reference to the drawings. FIG. 1A is a configuration diagram of the optical pickup device of the first embodiment, and FIG. 1B is an enlarged view of a base on which the rising mirror and the light amount control photodetector of the first embodiment are arranged. is there. FIG. 2 is a diagram showing an optical system of the optical pickup device of the first embodiment. In the first embodiment, the optical pickup device 30 performs at least one of recording and reproduction with respect to a DVD and a CD. However, the present invention is not limited to this, and at least one of recording and reproduction may be performed on the third optical disc.

  In FIG. 1A and FIG. 2, the light source 1 emits a laser beam having a wavelength λ1 = about 650 nm for DVD and a laser beam having a wavelength λ2 = about 780 nm for CD toward the optical disc 25. In the first embodiment, the light source 1 is a so-called two-wavelength laser light source that emits a laser beam for DVD and a laser beam for CD that are close to each other. However, a light source for emitting laser light for DVD and a light source for emitting laser light for CD may be arranged separately. Further, it may be combined with a laser beam having a wavelength λ3 = about 405 nm used for Blu-ray Disc or HD-DVD.

  The diffraction element 2 includes a DVD diffraction grating 2a and a CD diffraction grating 2b, and the DVD diffraction grating 2a and the CD diffraction grating 2b are arranged in series. Since the emission position of the DVD laser beam and the emission position of the CD laser beam are close to each other, both the DVD laser beam and the CD laser beam pass through the DVD diffraction grating 2a and the CD diffraction grating 2b. To do. The DVD diffraction grating 2a diffracts the DVD laser light and separates it into at least zero-order light and ± first-order light. The separated 0th-order light and ± 1st-order light of the laser beam for DVD are finally incident on the signal photodetector 8 and used for DVD tracking control. On the other hand, the DVD diffraction grating 2a passes the laser beam for CD as it is. That is, in the DVD diffraction grating 2a, the CD laser light is not separated into zero-order light and ± first-order light. The CD diffraction grating 2b transmits the DVD laser light as it is, and diffracts the CD laser light into at least zero-order light and ± first-order light and passes them. The separated 0th-order light and ± 1st-order light finally enter the signal photodetector 8 and are used for CD tracking control. In the CD diffraction grating 2b, the DVD laser light is not separated into zero-order light and ± first-order light.

  The integrated prism 3 is composed of a plurality of blocks formed of optical glass such as BK7. The slopes 3a and 3b are block boundaries. A polarization separation film 3c is formed on the inclined surface 3a. The polarization separation film 3c is formed of a dielectric multilayer film. The polarization separation film 3c transmits the laser beam for DVD and the laser beam for CD emitted from the light source 1 as forward light, and directs it toward the optical disc 25. Further, the polarization separation film 3c reflects the DVD laser light and the CD laser light reflected by the optical disk 25, which is the return light, and directs it to the signal photodetector 8. A reflective astigmatism generation element 3d is formed on the inclined surface 3b. The astigmatism generation element 3d is an element that varies the focal length in two orthogonal cross sections including the optical axis. That is, the astigmatism generation element 3d functions as a so-called cylindrical lens, cylindrical lens or a combination thereof, or a cylindrical reflecting mirror, a cylindrical reflecting mirror or a combination thereof. The laser beam that has passed through the astigmatism generation element 3d enters the signal photodetector 8 and is used for focus control. In the first embodiment, the astigmatism generation element 3d is a Fresnel lens-like reflection mirror, but may be a diffractive reflection mirror. Further, the astigmatism generation element 3d is formed inside the integrated prism 3. However, in addition to the integrated prism 3, the astigmatism generating element 3d is a cylindrical lens, a cylindrical lens or a combination thereof, or a cylindrical reflector, a cylindrical reflector or a combination thereof. It does not matter as an independent configuration.

  The wave plate 4 converts the DVD laser light and the CD laser light emitted from the light source 1 from linearly polarized light into circularly polarized light. Further, the circularly polarized DVD laser light and CD laser light reflected by the optical disk 25 are converted into linearly polarized light shifted by 90 degrees from the forward light. By making the linearly polarized light shifted by 90 degrees between the forward light and the backward light, the forward light and the backward light can be separated by the polarization separation film 3 c of the integrated prism 3.

  The collimating lens 5 is made of optical glass or optical plastic. The collimating lens 5 converts the laser beam for DVD and the laser beam for CD emitted from the light source 1 that is divergent light into substantially parallel light.

  The rising mirror 6 is a reflecting mirror that is raised substantially perpendicular to the optical disc 25 by changing the direction of the DVD laser light and the CD laser light that have been substantially parallel to the optical disc 25 until then. A film that reflects most of the laser beam and transmits part of the laser beam is formed on the surface of the rising mirror 6. If the transmittance is too low, the amount of light incident on the light amount control photodetector 9 decreases, and the light amount of the light source 1 described later cannot be controlled. On the other hand, if it is too high, the amount of laser light incident on the optical disc 25 is reduced, and the output of the reproduction signal, focus control signal, and tracking control signal is reduced. Although the transmittance is about 6% in the first embodiment, it is preferably in the range of about 4% to about 8%. Further, the back surface of the rising mirror 6 was made parallel to the front surface.

  The objective lens 7 is a condenser lens that focuses the DVD laser light and the CD laser light on the optical disk 25. The objective lens 7 is made of optical glass or optical plastic. In the optical disk 25, the distance from the surface to the recording surface differs between DVD and CD. In order to focus on the recording surface of the optical disc 25 according to the type, the objective lens 7 is a combination of a condensing lens and a Fresnel lens or a hologram lens, or a combination of providing a condensing lens for DVD with an aperture limiting means during CD reproduction. It is done. Further, a device that absorbs the difference in thickness and numerical aperture of the optical disc 25 can also be used.

  The signal photodetector 8 receives the laser beam for DVD and the laser beam for CD, which are emitted from the light source 1 and reflected by the optical disk 25, by the light receiving unit. There are a plurality of light receiving parts, and the light received by each light receiving part is converted into an electrical signal corresponding to the light quantity and output. The output electric signal is used for tracking control, focus control, reproduction of information recorded on the optical disc 25, and the like.

  The light quantity control light detector 9 serving as a detecting means detects the DVD laser light and the CD laser light emitted from the light source 1 and transmitted through the rising mirror 6 at the light receiving portion of the light receiving surface. The light quantity control light detector 9 converts the detected light into an electric signal corresponding to the light quantity and outputs it. The output electrical signal is used to control the output of the DVD laser light and the CD laser light emitted from the light source 1.

  As described above, the optical disk 25 is a DVD and a CD in the first embodiment. However, the present invention is not limited to this, and a Blu-ray Disc or HD-DVD may be used. The wavelength of laser light used for Blu-ray Disc and HD-DVD is about 405 nm.

  The DVD laser light and CD laser light emitted from the light source 1 are transmitted to the optical disk 25 via the diffraction element 2, the integrated prism 3, the wave plate 4, the collimating lens 5, the rising mirror 6, and the objective lens 7. Focus. Further, part of the light passes through the rising mirror 6 and enters the light amount control photodetector 9. The laser light reflected by the optical disk 25 enters the signal photodetector 8 via the objective lens 7, the rising mirror 6, the collimating lens 5, the wave plate 4, and the integrated prism 3.

  As shown in FIG. 1A, the optical pickup device 30 is configured by arranging various components on a base 10. The base 10 is a framework of the optical pickup device 30. The base 10 is made of an alloy material such as a Zn alloy or Mg alloy or a hard resin material, but an alloy material that can easily ensure rigidity is desirable. The base 10 is provided with mounting portions for arranging various parts at predetermined locations.

  The light source 1, the diffraction element 2, the integrated prism 3, and the signal photodetector 8 are fixed to one coupling member, and the coupling member is fixed to the base 10. The objective lens 7 is mounted on an objective lens driving device 11 that is a driving means, and the objective lens driving device 11 is fixed to the base 10. The wave plate 4, the collimating lens 5, the rising mirror 6, and the light amount control photodetector 9 are fixed to the base 10 directly or via other mounting members.

  As shown in FIG.1 (b), the base 10 has the penetration part 10a with the predetermined penetration area | region 10b. As shown in FIG. 1A, the light source 1 is disposed outside the penetrating region 10b of the penetrating portion 10a, and the objective lens driving device 11 is disposed within the penetrating region 10b of the penetrating portion 10a. Therefore, the objective lens 7 is held on the penetrating region 10b of the penetrating portion 10a by the objective lens driving device 11.

  Further, the penetrating portion 10a has a beam portion 10c that crosses the penetrating portion 10a in the lower region of the objective lens 7, and the rising mirror 6 and the light quantity control photodetector 9 are disposed on the beam portion 10c. The beam portion 10c has an extension piece 10f extending in the vertical direction from the central portion to the light source 1 side. The central portion has a mounting portion 10d for the light quantity control light detector 9 serving as a detecting means, and a mounting portion 10e for the rising mirror 6 at the tip of the extension piece 10f. The light amount control light detector 9 is fixed to the mounting portion 10 d of the light amount control light detector 9 so that the light detection surface is perpendicular to the optical disc 25. The raising mirror 6 is fixed to the mounting portion 10e of the raising mirror 6 in a state inclined by about 45 degrees.

  The objective lens driving device 11 is disposed in the penetrating region 10b of the penetrating portion 10a, the beam portion 10c that crosses the penetrating portion 10a is provided, and the rising mirror 6 and the light amount control photodetector 9 are fixed to the beam portion 10c. Thus, the light quantity control light detector 9 can be arranged on the opposite side of the light source 1 with the raising mirror 6 interposed therebetween. Therefore, in the actual configuration, it is possible to dispose the optical path bending mirror and to arrange the light quantity control photodetector 9. Therefore, the optical pickup device 30 can be made small and inexpensive.

  Moreover, since the beam part 10c crosses the penetration part 10a, the rigidity of the base 10 can be raised. Therefore, the base 10 can be made thin, and the optical pickup device 30 can be made thin.

  Further, the light amount control light detector 9 and the rising mirror 6 are respectively attached to the mounting portion 10d of the light amount control light detector 9 and the mounting portion 10e of the rising mirror 6 formed in one beam portion 10c. Can do. Therefore, space can be saved and the optical pickup device 30 can be made smaller. Further, since the surface for detecting the laser beam of the light quantity control photodetector 9 is substantially perpendicular to the optical disc 25, the dimension in the thickness direction of the optical pickup device 30 can be suppressed. 30 can be made thin.

  In the first embodiment, a condensing lens or the like is not disposed between the rising mirror 6 and the light quantity control photodetector 9, and the laser beam converted into parallel light by the collimator lens 5 is converted into parallel light. The light is incident on the light quantity control photodetector 9 as it is. Therefore, the optical pickup device 30 can be made inexpensive and more compact. A condensing lens may be disposed between the rising mirror 6 and the light amount control photodetector 9. In that case, the transmittance of the rising mirror 6 can be reduced, and the amount of light directed to the optical disk 25 can be increased.

  FIG. 3 is a view showing a penetration portion of the base of the first embodiment. A penetration region 10 b is provided in the penetration part 10 a of the base 10. The objective lens driving device 11 is fixed in the penetrating region 10b. A beam portion 10c is provided along the radial direction of the optical disc 25 in the central portion of the penetration region 10b, and the penetration region 10b is divided into two by the beam portion 10c. The beam portion 10c is provided below the penetrating portion 10a (the side far from the optical disc 25). If it is provided on the upper side, it is difficult to dispose the rising mirror 6. In addition, if it is provided at the upper and lower central portions, it is difficult to dispose the objective lens driving device 11.

  The beam portion 10c has an extension piece 10f extending in a direction perpendicular to the light source 1 side from the center portion, and has a mounting portion 10e for the rising mirror 6 at the tip of the extension piece 10f. The central portion of the beam portion 10c is rounded, and the light quantity control photodetector 9 is accommodated therein. This beaten portion may be a through hole. The wall surface on the mounting portion 10e side of the rising mirror 6 in the center is formed so as to rise in a direction perpendicular to the optical disk 25, and the light quantity control photodetector 9 is attached to this wall surface. The light quantity control photodetector 9 is fixed to the mounting portion 10d of the light quantity control photodetector 9 with an adhesive. The extension piece 10g extending from the central portion of the mounting portion 10d of the light quantity control light detector 9 to the central portion of the mounting portion 10e of the rising mirror 6 is punched so that light transmitted through the rising mirror 6 is blocked. Without being incident on the light quantity control photodetector 9.

  Further, the mounting portion 10e of the rising mirror 6 is provided with a linear raised portion to which the rising mirror 6 is fixed with an adhesive. The raising mirror 6 is fixed to the mounting portion 10e of the raising mirror 6 with an adhesive. The mounting accuracy of the rising mirror 6 can be improved by making the raised portion linear. In addition, the stress generated in the rising mirror 6 can be kept small, and the aberration of light incident on the optical disk 25 can be reduced. The raised portion is inclined at about 45 degrees so that the rising mirror 6 is attached at an inclination of about 45 degrees.

  4A is a configuration diagram from above of the objective lens driving device according to the first embodiment, and FIG. 4B is a configuration diagram from below. The objective lens 7 is fixed to the penetrating portion of the lens holder 12. A lens holder 12 that is a holder for fixing the objective lens 7 is formed of resin or the like. The laser light reflected by the raising mirror 6 passes through the penetrating portion of the lens holder 12 and enters the objective lens 7. One ends of a plurality of elastic members 13 are fixed to both ends of the lens holder 12. The elastic member 13 is formed of a metal having conductivity and elasticity. The other end of the elastic member 13 is fixed to both ends of the holding member 14. The holding member 14 is fixed to a yoke 15 serving as a base of the objective lens driving device 11. In this manner, the lens holder 12 on which the objective lens 7 is mounted is supported by the elastic member 13 so as to be movable in the focus direction and the tracking direction of the optical disc 25.

  The yoke 15 is a magnetic material and fixes a magnet 17. The lens holder 12 has a focus coil 18 and a tracking coil 19 fixed at positions close to the magnet 17. One end side of the elastic member 13 is electrically connected to the focus coil 18 or the tracking coil 19. The other end side of the elastic member 13 is connected to the flexible printed circuit board 16. When a current flows from the flexible printed circuit board 16 to the focus coil 18 and the tracking coil 19 through the elastic member 13, a driving force for moving the lens holder 12 in the focus direction and the tracking direction is generated.

  The magnet 17, the focus coil 18, and the tracking coil 19 are arranged around the objective lens 7, but are spaced along the circumferential tangential direction of the optical disc 25, and the laser light emitted from the light source 1 passes therethrough. I can do it. The yoke 15 is also notched so that the laser beam can pass. Further, the yoke 15 connects the lens holder 12 side and the holding member 14 side from above. The light quantity control photodetector 9 is disposed between the lens holder 12 side and the holding member 14 side. Since the yoke 15 is on the upper side of the light quantity control light detector 9, the yoke 15 and the light quantity control light detector 9 are arranged without contact.

  FIG. 5 is a diagram illustrating a state in which the objective lens driving device according to the first embodiment is attached to the base. The light quantity control light detector 9 is fixed to the mounting portion 10d of the light quantity control light detector 9 of the beam portion 10c of the base 10. The rising mirror 6 is fixed to the mounting portion 10 e of the rising mirror 6. The objective lens driving device 11 is fixed to the penetrating region 10b of the penetrating portion 10a of the base 10 from above. At that time, the raising mirror 6 is disposed below the objective lens 7. The light quantity control photodetector 9 is disposed in a region between the rising mirror 6 and the holding member 14. Since there is a space in the portion of the objective lens driving device 11 where the rising mirror 6 and the light amount control photodetector 9 are housed, the rising mirror 6 and the light amount control photodetector 9 are different from the objective lens driving device 11. Do not touch.

  Thus, it is not necessary to provide a space for disposing the light quantity control light detector 9 outside the objective lens driving device 11, and a space for disposing the light amount control light detector 9 can be saved. Therefore, the optical pickup device 30 can be reduced in size.

  FIG. 6A is a diagram showing the routing of the flexible printed circuit board for the light quantity control photodetector according to the first embodiment, FIG. 6B is a diagram when the objective lens driving device is incorporated, and FIG. 6C. FIG.

  The flexible printed circuit board 20 used for the light quantity control light detector 9 is connected to the light quantity control light detector 9 and plays a role of transmitting an output signal from the light quantity control light detector 9 to the outside. The flexible printed circuit board 20 is arranged from the light quantity control photodetector 9 along the one upper surface side of the beam portion 10c so as to face the penetration region 10b of the penetration portion 10a of the base 10 to the outside. The flexible printed circuit board 20 is bent at the outer edge portion of the penetrating region 10b and is disposed so as to reach the upper surface side of the base 10 along the wall surface. The flexible printed circuit board 20 is further bent on the upper surface side of the base 10, arranged along the upper surface side of the base 10, and goes outward.

  Since the flexible printed circuit board 20 is connected to the light quantity control photodetector 9 from the outside of the penetrating portion 10a without passing through the holding member 14 portion of the objective lens driving device 11, the optical pickup device 30 can be made thin.

  When the objective lens driving device 11 is arranged, the flexible printed circuit board 20 passes through the lower surface side of the elastic member 13. The elastic member 13 swings in the vertical direction in order to move the objective lens 7 in the focus direction. Therefore, when the flexible printed circuit board 20 is arranged in a state of floating from the beam portion 10c, the flexible printed circuit board 20 and the elastic member 13 may come into contact with each other. Therefore, the slit 10g is provided in the beam portion 10c of the base 10, and the end of the flexible printed circuit board 20 is inserted into the slit 10g, so that the flexible printed circuit board 20 moves in the direction perpendicular to the optical disk 25. regulate. Since the possibility that the flexible printed board 20 moves and contacts the elastic member 13 is reduced, the reliability of the optical pickup device 30 can be increased.

  With the configuration as described above, in the optical pickup device 30, the light source 1, the rising mirror 6, and the light amount control photodetector 9 are arranged on substantially one straight line. When there is an optical path bending mirror, the optical path is bent by the optical path bending mirror. Therefore, a triangular space formed by the light source 1, the optical path bending mirror, and the rising mirror 6 is created in the optical pickup device 30. This space is an unnecessary space, but it can be removed by arranging the light source 1, the raising mirror 6, and the light amount control photodetector 9 on substantially one straight line.

  As described above, in the optical pickup device 30 according to the first embodiment, the objective lens driving device 11 serving as a driving unit is disposed in the penetrating region 10b of the penetrating portion 10a. And the beam part 10c which crosses the penetration part 10a was provided, and the standing mirror 6 and the photodetector 9 for light quantity control which is a detection means were fixed to the beam part 10c. As a result, the light quantity control photodetector 9 can be arranged on the opposite side of the light source 1 with the rising mirror 6 interposed therebetween. Therefore, in the actual configuration, it is possible to dispose the optical path bending mirror and to arrange the light quantity control photodetector 9. Therefore, the optical pickup device 30 can be made small and inexpensive.

  Moreover, since the beam part 10c crosses the penetration part 10a, the rigidity of the base 10 can be raised. Therefore, the base 10 can be made thin, and the optical pickup device 30 can be made thin.

(Embodiment 2)
The second embodiment will be described with reference to the drawings. FIG. 7 is a configuration diagram of the optical pickup module according to the second embodiment, and FIG. 8 is a configuration diagram of the optical disk device according to the second embodiment.

  In FIG. 7, the drive mechanism of the optical disk device 70 including a rotation drive unit that rotates the optical disk 25 and a moving unit that moves the optical pickup device 30 closer to or away from the rotation drive unit is referred to as an optical pickup module 50. The base 51 forms a framework of the optical pickup module 50, and the optical pickup module 50 is configured by disposing each component directly or indirectly on the base 51.

  The rotation drive unit includes a spindle motor 52 having a turntable 52a on which the optical disk 25 is placed. The spindle motor 52 is fixed to the base 51. The spindle motor 52 generates a rotational driving force that rotates the optical disc 25.

  The moving unit includes a feed motor 53, a screw shaft 54, and guide shafts 55 and 56. The feed motor 53 is fixed to the base 51. The feed motor 53 generates a rotational driving force necessary for the optical pickup device 30 to move between the inner periphery and the outer periphery of the optical disc 25. A stepping motor, a DC motor, or the like is used as the feed motor 53. The screw shaft 54 has a groove formed in a spiral shape, and is connected to the feed motor 53 directly or via several stages of gears. In the second embodiment, it is directly connected to the feed motor 53. The guide shafts 55 and 56 are fixed to the base 51 via guide shaft holding members at both ends. The guide shafts 55 and 56 support the optical pickup device 30 so as to be movable. The optical pickup device 30 includes a rack 23 having guide teeth that mesh with the grooves of the screw shaft 54. Since the rack 23 converts the rotational driving force of the feed motor 53 transmitted to the screw shaft 54 into a linear driving force, the optical pickup device 30 can move between the inner periphery and the outer periphery of the optical disc 25.

  The rotation driving unit is not limited to the configuration described in the second embodiment as long as it can rotate the optical disc 25 at a predetermined rotation speed. The moving unit is not limited to the configuration described in the second embodiment as long as it can move the optical pickup device 30 to a predetermined position between the inner periphery and the outer periphery of the optical disc 25.

  The optical pickup device 30 is obtained by attaching covers 21 and 22 to the configuration of FIG. The optical pickup device 30 includes a laser light source 1, an objective lens 7 that focuses the laser light on the optical disc 25, and an objective lens driving device 11 that is a drive unit that drives the objective lens 7 relative to the optical disc 25. Further, the direction of the laser beam is changed toward the objective lens 7 and the rising mirror 6 that transmits a part of the laser beam and the laser beam that has passed through the rising mirror 6 in order to control the light quantity of the light source 1 are detected. And a light quantity control light detector 9 which is a detecting means. Moreover, the light source 1, the objective lens 7, the objective lens drive device 11, the raising mirror 6, and the base 10 which arrange | positions the light quantity control photodetector 9 are provided. The base 10 has a penetrating portion 10a having a predetermined penetrating region 10b. The light source 1 is disposed outside the penetrating region 10b of the penetrating portion 10a, and the objective lens driving device 11 is disposed within the penetrating region 10b of the penetrating portion 10a. The objective lens 7 is held on the penetrating region 10b of the penetrating portion 10a by the objective lens driving device 11. The penetrating portion 10a has a beam portion 10c that traverses the penetrating portion 10a in the lower region of the objective lens 7, and the rising mirror 6 and the light amount control photodetector 9 are arranged in the beam portion 10c.

  The objective lens driving device 11 is disposed in the penetrating region 10b of the penetrating portion 10a, the beam portion 10c that crosses the penetrating portion 10a is provided, and the rising mirror 6 and the light amount control photodetector 9 are fixed to the beam portion 10c. Thus, the light quantity control light detector 9 can be arranged on the opposite side of the light source 1 with the raising mirror 6 interposed therebetween. Therefore, in the actual configuration, it is possible to dispose the optical path bending mirror and to arrange the light quantity control photodetector 9. Therefore, the optical pickup device 30 is small and inexpensive.

  Moreover, since the beam part 10c crosses the penetration part 10a, the rigidity of the base 10 can be raised. Therefore, the base 10 can be made thin. Therefore, the optical pickup device 30 is also thin.

  The inclination of the guide shafts 65 and 66 is adjusted by an adjustment mechanism that constitutes the guide shaft holding member so that the laser light emitted from the objective lens 7 of the optical pickup device 30 is incident on the optical disk 25 at a right angle.

  In FIG. 8, a casing 71 is configured by combining an upper casing 71a and a lower casing 71b and fixing them together using screws or the like. The tray 72 is provided in the casing 71 so as to freely appear and disappear. In the tray 72, the optical pickup module 50 to which the cover 57 is attached is arranged from the lower surface side. The cover 57 has an opening to expose the objective lens 7 of the optical pickup device 30 and the turntable 52a of the spindle motor 52. Further, in the case of the second embodiment, the feed motor 53 is also exposed so that the thickness of the optical pickup module 50 is reduced by the thickness of the cover 57. The tray 72 has an opening and exposes at least a part of the objective lens 7, the turntable 52 a of the spindle motor 52, and the cover 57. The bezel 73 is provided on the front end surface of the tray 72 and is configured to close the entrance and exit of the tray 72 when the tray 72 is stored in the casing 71. The bezel 73 is provided with an eject switch 74, and when the eject switch 74 is pressed, the engagement between the casing 71 and the tray 72 is released, and the tray 72 can be brought into and out of the casing 71. The rails 75 are slidably attached to both sides of the tray 72 and the casing 71, respectively. There are circuit boards (not shown) inside the casing 71 and the tray 72, and a signal processing system IC, a power supply circuit, and the like are mounted. The external connector 76 is connected to a power / signal line provided in an electronic device such as a computer. Then, electric power is supplied into the optical disc device 70 via the external connector 76, an electric signal from the outside is guided into the optical disc device 70, or an electric signal generated by the optical disc device 70 is sent to an electronic device or the like. To do.

  In the second embodiment, the optical pickup device 30 is small and inexpensive. It is also thin. Therefore, the optical disk device 70 can also be made small, inexpensive and thin.

  As described above, the optical pickup device and the optical disk device of the present invention can be realized without an optical path bending mirror, and are small and inexpensive. Therefore, it is preferably mounted on an electronic device such as a personal computer or a notebook computer.

(A) Configuration diagram of the optical pickup device of the first embodiment, (b) Enlarged view of the base on which the rising mirror and the light quantity control photodetector of the first embodiment are arranged. The figure which shows the optical system of the optical pick-up apparatus of this Embodiment 1. The figure which shows the penetration part of the base of this Embodiment 1. (A) Configuration diagram from above of objective lens driving device according to the first embodiment, (b) Configuration diagram from below The figure which shows a mode that the objective lens drive device of this Embodiment 1 is attached to a base. (A) The figure which shows the drawing of the flexible printed circuit board for the photodetector for light quantity control of this Embodiment 1, (b) The figure at the time of incorporating an objective-lens drive device, (c) AA sectional drawing Configuration diagram of optical pickup module of Embodiment 2 Configuration diagram of optical disc apparatus of Embodiment 2 The figure which shows the structure of the optical system of the conventional optical pick-up apparatus. The figure which shows the structure of the conventional optical pick-up apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Light source 2 Diffraction element 2a Diffraction grating for DVD 2b Diffraction grating for CD 3 Integrated prism 3a, 3b Slope 3c Polarization separation film 3d Astigmatism generation element 4 Wave plate 5 Collimating lens 6 Raising mirror 7 Objective lens 8 Signal light detection 9 Photodetector for light quantity control 10 Base 10a Penetrating portion 10b Penetrating region 10c Beam portion 10d, 10e Mounting portion 10f Extension piece 10g Slit 11 Objective lens driving device 12 Lens holder 13 Elastic member 14 Holding member 15 Yoke 16 Flexible printed circuit board DESCRIPTION OF SYMBOLS 17 Magnet 18 Focus coil 19 Tracking coil 20 Flexible printed circuit board 21, 22 Cover 23 Rack 25 Optical disk 30 Optical pick-up apparatus 50 Optical pick-up module 51 Base 52 Spindle motor 53 Feed motor 5 The screw shaft 55 and guide shaft 57 cover 70 optical disc device 71 housing 71a upper housing 71b lower housing 72 tray 73 Bezel 74 Schima wallichii transfected switch 75 rail 76 external connector

Claims (10)

A laser light source;
An objective lens for focusing the laser beam on an optical disc;
Driving means for driving the objective lens with respect to the optical disc;
A rising mirror that changes the direction of the laser beam toward the objective lens and transmits a part of the laser beam;
Detecting means for detecting laser light transmitted through the raising mirror in order to control the light amount of the light source;
A base on which the light source, the objective lens, the drive means, the rising mirror, and the detection means are arranged,
The base has a penetrating portion having a predetermined penetrating region,
The light source is disposed outside the penetrating region of the penetrating portion, the driving means is disposed in the penetrating region of the penetrating portion, and the objective lens is held on the penetrating region of the penetrating portion by the driving unit;
The optical pickup device, wherein the penetrating portion includes a beam portion that traverses the penetrating portion in a lower region of the objective lens, and the rising mirror and the detection unit are disposed in the beam portion. The beam portion has an extension piece extending in the vertical direction from the central portion to the light source side, and has an attachment portion for the detection means at the center portion, and the rising mirror is provided at the tip of the extension piece. The optical pickup device according to claim 1, further comprising a mounting portion. The drive means includes a holder that fixes the objective lens, an elastic member that elastically supports the holder at one end, and a holding member that holds the other end of the elastic member, and the detection means includes the rising mirror The optical pickup device according to claim 1, wherein the optical pickup device is disposed between the holding member and the holding member. 2. The optical pickup device according to claim 1, wherein a surface of the detecting means for detecting the laser beam is in a direction substantially perpendicular to the optical disc. A collimating lens is provided on the optical path between the light source and the rising mirror to make the laser light substantially parallel light, and the laser light as the parallel light is incident on the detection means. The optical pickup device according to claim 1. A flexible printed circuit board connected to the detection means from the outside of the penetrating part, the flexible printed circuit board being connected via the beam part, and the surface of the beam part on the optical disc side in the beam part 4. The optical pickup device according to claim 3, wherein the optical pickup device is disposed between the elastic member and the elastic member. 7. The beam portion has a slit, and the flexible printed circuit board is restricted from moving in a direction perpendicular to the optical disk by inserting an end of the flexible printed circuit board into the slit. The optical pickup device described. 2. The optical pickup device according to claim 1, wherein a transmittance of the rising mirror that transmits the laser light is 4% or more and 8% or less. 2. The optical pickup device according to claim 1, wherein the light source, the rising mirror, and the detection means are arranged on a substantially straight line. A laser light source;
An objective lens for focusing the laser beam on an optical disc;
Driving means for driving the objective lens with respect to the optical disc;
A rising mirror that changes the direction of the laser beam toward the objective lens and transmits a part of the laser beam;
Detecting means for detecting laser light transmitted through the raising mirror in order to control the light amount of the light source;
A base on which the light source, the objective lens, the drive means, the rising mirror, and the detection means are arranged,
The base has a penetrating portion having a predetermined penetrating region,
The light source is disposed outside the penetrating region of the penetrating portion, the driving means is disposed in the penetrating region of the penetrating portion, and the objective lens is held on the penetrating region of the penetrating portion by the driving unit;
The optical disc apparatus, wherein the penetrating portion has a beam portion traversing the penetrating portion in a lower region of the objective lens, and the rising mirror and the detecting means are arranged in the beam portion.

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