JP2012043498A - Optical pickup device and manufacturing method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an optical pickup device and a manufacturing method thereof, capable of easily positioning an actuator to be connected to a flexible wiring board.SOLUTION: A principal surface of a housing 28 is provided with a step part 48. An intermediate part of a flexible wiring board 38 connected to an actuator 36 is provided with a bent part 50, which is in close contact with the step part 48 of the housing 28. The bent part 50 of the flexible wiring board 38 prevents the flexible wiring board 38 from suffering residual stress even when the actuator 36 is moved for positioning.

Description

  The present invention relates to an optical pickup device and a manufacturing method thereof. In particular, the present invention relates to an optical pickup device to which an actuator is connected via a flexible wiring board and a manufacturing method thereof.

  The optical pickup device has a function of irradiating an optical disc with laser light having a predetermined wavelength emitted from a light emitting element, and detecting the laser light reflected by the information recording layer of the optical disc with a light receiving element (Patent Document 1). As a result, an information reading operation or writing operation is performed on the optical disc.

  Further, in the optical pickup device, tracking servo and focus servo are performed by detecting the laser light reflected by the information recording layer of the optical disk in order to accurately irradiate the optical disk with the laser light. Here, the focus servo is an adjustment mechanism for accurately focusing the laser beam on the information recording layer of the optical disc. The tracking servo is an adjustment mechanism for causing the laser beam to follow the track of the optical disc.

JP 2005-216436 A

  Since such a servo mechanism is performed by applying a control voltage to a control coil included in the actuator, the actuator needs to be electrically connected to the outside. The actuator is connected via a flexible wiring board.

  On the other hand, in the method of manufacturing the optical pickup device, the skew adjustment is performed after the actuator is accommodated in the housing. In this skew adjustment, the laser beam focused by the objective lens supported by the actuator is adjusted to be at a predetermined position.

  However, in the skew adjustment process, the flexible wiring board is already fixed to the actuator. Further, the flexible wiring board is fixed to the actuator in a plane. Therefore, when the actuator is moved to adjust the skew, the movement of the actuator may be hindered by the flexible wiring board connected to the actuator. Further, there is a problem that the flexible wiring board is twisted.

  Further, the actuator may be fixed with the bending stress or the tensile stress applied to the flexible wiring board due to the movement of the actuator. If this stress is large, the flexible wiring board may be separated from the connection portion when temperature change, humidity change, or external impact is applied to the optical pickup device under use conditions.

  The present invention has been made in view of such problems, and an object of the present invention is to provide an optical pickup device that prevents excessive stress from remaining on a flexible wiring board and a method for manufacturing the same. is there.

  An optical pickup device of the present invention includes a housing having a first main surface and a second main surface, an actuator that holds an objective lens movably, and a flexible wiring board that is electrically connected to the actuator. A bent portion obtained by bending a middle portion of the flexible wiring board is disposed at a step portion in which the second main surface of the housing has a step shape.

  The present invention is a method of manufacturing an optical pickup device that emits laser light to an information recording medium and detects the laser light reflected by the information recording medium, and includes a housing having a first main surface and a second main surface. A step of preparing and preparing an actuator for holding the objective lens movably in the housing while being connected to the flexible wiring board, and adjusting the position of the actuator while causing the objective lens to emit the laser light In the step of incorporating, in the step of incorporating, a bent portion provided in the middle portion of the flexible wiring board is disposed in a stepped portion provided in the second main surface of the housing, and in the step of adjusting the position, The bent portion of the flexible wiring board is deformed in accordance with the position adjustment of the actuator.

  According to the present invention, the stepped bent portion is provided on the flexible wiring board connected to the actuator. Therefore, even if the actuator is moved / tilted for skew adjustment, the bent portion of the flexible wiring board is deformed accordingly, so that the movement of the actuator is not hindered by the flexible wiring board. Furthermore, since the movement for adjusting the actuator suppresses excessive bending stress and tensile stress from remaining on the flexible wiring board, disconnection of the flexible wiring board under use conditions and the like can be prevented.

  Further, since the bent portion of the flexible wiring board is in close contact with the step portion of the housing, the bent portion does not protrude to the outside.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows the optical pick-up apparatus of this invention, (A) is a perspective view which shows the optical pick-up apparatus which made the surface which an objective lens exposes the upper surface, (B) is a perspective view which shows the state reversed up and down. is there. BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows the optical pick-up apparatus of this invention, (A) is a perspective view which expands and shows the part by which the flexible wiring board connected with an actuator is arrange | positioned, (B) is a perspective view which shows the level | step-difference part of a housing FIG. It is a figure which shows the flexible wiring board used for the optical pick-up apparatus of this invention, (A) is an expanded view, (B) is a perspective view which shows the flexible wiring board in the state bent and integrated in a housing. It is a figure which shows the optical element integrated in the optical pick-up apparatus of this invention. It is a figure which shows the state in which an actuator is integrated in a housing in the manufacturing method of the optical pick-up apparatus of this invention. In the manufacturing method of the optical pick-up apparatus of this invention, it is a figure which shows the process of skew adjustment, (A) is a figure which shows a flexible wiring board, (B) is sectional drawing which shows the actuator by which position adjustment is carried out. is there.

  With reference to FIG. 1, the structure of the optical pick-up apparatus 10 of this form is demonstrated. FIG. 1A is a perspective view showing the main surface of the optical pickup device 10 where the objective lens 33 is exposed, and FIG. 1B is a perspective view showing the housing 28 on the opposite surface. In the following description, a main surface on which the objective lens 33 is disposed is referred to as an upper surface, and a main surface facing the upper surface is referred to as a lower surface.

  The optical pickup device 10 focuses a laser beam of BD (Blu-ray Disc), DVD (Digital Versatile Disk) or CD (Compact Disc) standard on an information recording layer of an optical disc (information recording medium), and records the information. It has a function of receiving reflected light from the layer and converting it into an electrical signal. The optical pickup device 10 includes, for example, a light emitting chip for BD, a light emitting chip for DVD and a CD.

  Laser light emitted from the optical pickup device 10 includes BD standard laser light (blue-violet wavelength band 400 nm to 420 nm), DVD standard laser light (red wavelength band 645 nm to 675 nm), and CD standard laser light (infrared). Wavelength band 765 nm to 805 nm). Here, the optical pickup device 10 does not necessarily correspond to laser beams of three types of standards, and may be a type corresponding to laser beams of one or two standards.

  The optical pickup device 10 includes a housing 28 made of a resin material or a metal material, various optical elements built in the housing 28, and a flexible wiring board that is electrically connected to the optical elements.

  On the upper surface of the housing 28, an actuator 36 that holds the objective lens 33 movably is disposed. Further, the flexible wiring board 26 is fixed to the upper surface of the housing 28 in a folded state. Various optical elements are disposed inside and on the side of the housing 28. The upper surface of the housing 28 in a region other than the actuator 36 may be covered with a cover made of a metal plate such as stainless steel.

  Here, the optical elements provided in the housing 28 can be roughly classified into two types. Specifically, the first optical element electrically connected to the outside and the second optical element such as a half mirror that transmits or reflects the laser light in order to emit and receive the laser light described above. Broadly divided. In this embodiment, the first optical element is electrically connected via the flexible wiring board 26. Specifically, the LD (laser diode) that emits the laser light and the laser light are received. PDIC (Photo Detector IC), the actuator 36, etc. which correspond. Further, the first optical element may include a chip resistor or a package with a built-in control element fixed to the flexible wiring board 26 for noise countermeasures or the like. Details of the optical element built in the housing 28 will be described later with reference to FIG.

  The housing 28 is made of a resin material or a metal material (for example, magnesium) integrally formed by injection molding. In addition, guide holes 30 and guide grooves 32 are provided at both end portions of the housing 28. Under use conditions, a guide shaft is inserted into the guide hole 30, and another guide shaft is engaged with the guide groove 32. The optical pickup device 10 moves in the radial direction of the disc along these guide shafts.

  In this embodiment, three flexible wiring boards are used. Specifically, the flexible wiring board 26 (see FIG. 1A) having a single layer structure, the flexible wiring board 34 having a multilayer wiring structure (see FIG. 1A), and the actuator 36 are used. A flexible wiring board 38 (see FIG. 1B) is applied.

  The flexible wiring board 26 connects the first optical element built in the optical pickup device 10 to the outside. Further, the flexible wiring board 26 has a function of electrically connecting the first optical elements provided in the housing 28. The flexible wiring board 26 is fixed to the upper surface portion of the housing 28 in a state where the flexible wiring board 26 is folded by being subjected to a plurality of bending processes. Since the flexible wiring board 26 has a function of connecting the optical pickup device 10 itself to the outside, it may be referred to as a main board.

  On the other hand, the flexible wiring board 34 connects one of the first optical elements, the DVD and CD LD, and the package 22 containing the control element for controlling the LD, and the wiring pattern is formed on both main surfaces of the substrate. Is formed. The wiring pattern formed on both surfaces of the flexible wiring board 34 is formed thicker than the wiring pattern formed on the flexible wiring board 26. As a result, sufficient response characteristics can be obtained, noise can be reduced, and a writing operation can be stably performed by the LD for DVD and CD.

  As shown in FIG. 1B, the flexible wiring board 38 is a board for connecting the actuator 36 and the flexible wiring board 26, and is arranged in a concave region 46 in which the lower surface of the housing 28 is recessed. Specifically, the control coil provided in the actuator 36 is connected to the wiring pattern of the flexible wiring board 38.

  With reference to FIG. 2, the flexible wiring board 38 connected to the actuator 36 will be described. FIG. 2A is an enlarged perspective view showing a portion where the flexible wiring board 38 is arranged, and FIG. 2B is a perspective view showing the housing 28 of this portion.

  Referring to FIG. 2A, the optical pickup device of this embodiment is thin and applicable to an optical drive of a notebook personal computer. Accordingly, the housing 28 constituting the outer shape of the optical pickup device is also very thin. For this reason, a part of the relatively thick actuator 36 among the optical components is exposed from the bottom of the housing 28.

  The actuator 36 is electrically connected to the outside via the flexible wiring board 38 in order to adjust the position of the objective lens according to the applied voltage. In this embodiment, the flexible wiring board 38 to which the actuator 36 is connected is disposed on the lower surface of the housing 28.

  The flexible wiring board 38 is separate from the flexible wiring board 26 connected to the outside. Specifically, since the actuator 36 needs to be incorporated in the housing 28 while being connected to the flexible wiring board, the actuator 36 needs to be prepared while being connected to the flexible wiring board. However, the flexible wiring board 26 as the main board is a large-sized board having a relatively complicated shape. For this reason, if the actuator 36 is stored in a state of being connected to the flexible wiring board 26, there is a risk that the elongated wire provided in the actuator 36 may be deformed. Therefore, in this embodiment, the flexible wiring board 38 having a relatively small and simple shape is stored in a state where it is connected to the actuator 36. By doing so, it is possible to prevent the elongated wire included in the actuator 36 from being damaged during storage or transportation.

  The flexible wiring board 38 and the flexible wiring board 26 are connected by the connecting portion 40. In this connection part 40, the wiring patterns provided in both flexible sheets are soldered together.

  The flexible wiring board 38 is housed in a concave region 46 in which the lower surface of the housing 28 is partially recessed in the thickness direction. By doing so, the protrusion of the flexible wiring board 38 to the outside is prevented, and the outer shape of the optical pickup device is reduced.

  Further, a bent portion 50 is provided by bending a middle portion of the flexible wiring board 38 in a step shape. By doing in this way, it is suppressed that a stress remains in the flexible wiring board 38 with adjustment of the actuator 36. Specifically, the adjustment of the actuator 36 is performed after the actuator 36 is assembled in the housing 28 and the flexible wiring boards are connected to each other by the connecting portion 40. Therefore, if the flexible wiring board 38 is flat, when the actuator 36 is moved for adjustment, the flexible wiring board 38 becomes a product with bending stress and tensile stress remaining.

  As a countermeasure, a bent portion 50 is provided in the middle of the flexible wiring board 38. Thus, even if the actuator 36 to which the flexible wiring board 38 is fixed is moved for adjustment, this movement is absorbed by the bending portion 50 being deformed. As a result, the remaining stress on the flexible wiring board 38 is suppressed. Furthermore, the tone of the actuator 36 becomes smooth.

  On the lower surface of the housing 28, a stepped portion 48 is provided in accordance with the shape of the bent portion 50 of the flexible wiring board 38 (see FIG. 2B). The bent portion 50 of the flexible wiring board is in contact with the stepped portion 48. By doing in this way, it is prevented that the bending part 50 protrudes outside.

  A protruding portion 42 is provided by partially protruding the side wall of the concave region 46, and a cutout portion 44 is provided in the flexible wiring board 38 at a location corresponding to the protruding portion 42. Therefore, the flexible wiring board 38 is disposed at a predetermined position of the housing 28 by fitting the notch 44 of the flexible wiring board 38 to the protrusion 42 of the housing 28. Here, a set of protrusions 42 and notches 44 are shown, but a plurality of these may be provided.

  With reference to FIG. 3, the structure of the flexible wiring board 38 connected to the actuator will be described. 3A is a plan view showing the flexible wiring board 38 in an unfolded state, and FIG. 3B is a perspective view showing the flexible wiring board 38 in a state of being bent and incorporated in the housing 28.

  With reference to these drawings, the flexible wiring board 38 includes a connection portion 54 connected to the actuator, a bending portion 60 whose middle portion is bent by 180 degrees, a wiring portion 56 continuous with the bending portion 60, and a staircase shape. The bent portion 50 is bent, the wiring portion 58 is continuous with the bent portion 50, and the connection portion 52 is connected to the flexible wiring board 26.

  In the connection portions 54 and 52, pads made of a wiring pattern are exposed for solder connection. Further, the end portion of the connection portion 54 connected to the actuator is cut out in a U shape, which is to avoid a screw provided on the side surface of the actuator. Further, the pads arranged in the connection portion 54 are connected to connection pads provided on the side surface of the actuator via solder.

  The bending portion 60 is bent 180 degrees in the middle. Thereby, the movement of the actuator to which the flexible wiring board 38 is connected becomes smoother.

  At both ends of the bent portion 50, the flexible wiring board 38 is bent about 90 degrees to realize a step-like bent shape.

  The two cutouts 44 provided on the side of the wiring part 58 are fitted into the protrusions of the housing, so that the flexible wiring board 38 is disposed at a predetermined position of the housing. In addition, movement and detachment of the flexible wiring board 38 under use conditions are prevented by fitting the notch portion 44 to the projection portion of the housing.

  The bending of the flexible wiring board 38 as shown in FIG. 3B is performed by pressing with a mold.

  Here, the flexible wiring substrate 38 may be a single layer substrate or a multilayer substrate. In the case of a single-layer substrate, a wiring pattern made of copper having a thickness of about 10 μm is provided only on one main surface of a base material made of a resin material such as polyimide having a thickness of about 10 μm. Furthermore, one main surface of the substrate and the wiring pattern are covered with a coating layer made of polyimide having a thickness of about 10 μm.

  Next, with reference to FIG. 4, the optical element housed in the housing of the optical pickup device 10 will be described.

  The specific configuration of the optical pickup device 10 includes objective lenses 82 and 84, rising mirrors 86 and 88, quarter-wave plates 90, reflecting plates 92 and 94, collimating lenses 96, and prisms 98 and 100. An anamorphic lens 102, a PDIC 104, diffraction gratings 110 and 112, and laser devices 106 and 108.

  In this embodiment, one optical path is shared by three standard laser beams. As a result, the number of parts required for the optical pickup device 10 corresponding to three wavelengths is reduced. Therefore, the cost is realized and the optical pickup device 10 as a whole is reduced in size.

  The laser device 108 is a package of a light emitting element that emits a laser beam irradiated to a BD standard disc 80.

  The laser device 106 is a package of a light emitting element that emits laser light applied to a DVD 80 and a CD 80 of the CD standard.

  Here, the laser devices 106 and 108 may be so-called CAN type packages or lead frame type packages.

  The diffraction grating 110 has a function of separating laser light (DVD standard or CD standard) emitted from the laser device 106 into 0th-order diffracted light, + 1st-order diffracted light, and −1st-order diffracted light.

  Similarly, the diffraction grating 112 has a function of separating BD standard laser light emitted from the laser device 108 into 0th-order diffracted light, + 1st-order diffracted light, and −1st-order diffracted light.

  The anamorphic lens 102 is a lens for imparting aberration to the passing laser beam, and is also referred to as an anamorphic lens.

  The PDIC 104 has a built-in photodiode integrated circuit element for signal detection that functions as a photodetector, and receives a BD standard, DVD standard, or CD standard laser beam and generates a light receiving output including an information signal component. Further, the PDIC 104 generates servo signal components used for focus servo and tracking servo.

  The prism 100 incorporates a reflective surface having polarization selectivity with respect to BD standard laser light emitted from the laser device 108. Laser light that is linearly polarized light in the S direction emitted from the laser device 108 is reflected in the + X direction by the reflecting surface of the prism 100. The return light reflected by the disk 80 is converted into linearly polarized light in the P direction by the action of the quarter-wave plate 90 and passes through the reflecting surface of the prism 100 in the −X direction.

  The prism 98 incorporates a reflecting surface having wavelength selectivity and polarization selectivity. Specifically, the prism 98 transmits BD standard laser light emitted from the laser device 108 regardless of the deflection direction. On the other hand, DVD standard and CD standard laser light emitted from the laser device 106 is reflected or transmitted by the reflecting surface of the prism 98 depending on the polarization direction. Specifically, a DVD standard or CD standard laser beam is emitted from the laser device 106, and these laser beams are linearly polarized light in the S direction. The laser light emitted in the + Y direction from the laser device 106 is reflected in the + X direction by the reflecting surface of the prism 98 and then reaches the disk 80 via various optical elements. Laser light that is return light reflected by the information recording layer of the disk 80 is converted into linearly polarized light in the P direction by the action of the quarter-wave plate 90, and the reflecting surface of the prism 98 is changed from the + X direction to − Transmits in the X direction.

  The collimating lens 96 is a lens for making the laser light emitted from the laser devices 106 and 108 into parallel light.

  The reflectors 92 and 94 are for reflecting the laser light emitted from the laser devices 106 and 108 in a predetermined direction. Here, the reflectivity at which the reflectors 92 and 94 reflect the laser light may be 100%, or the reflectivity of the laser light having a specific wavelength or deflection direction may be adjusted to supplement the functions of the prisms 98 and 100. good.

  The quarter-wave plate 90 is an optical element that causes a phase difference in incident laser light. Therefore, when the laser light of linearly polarized light in the S direction emitted from the laser devices 106 and 108 passes through the quarter wavelength plate 90, it is converted into laser light of circularly polarized light. Further, when the laser light converted into circularly polarized light is reflected by the information recording layer of the disk 80 and passes through the quarter-wave plate 90 again, it is converted into laser light of linearly polarized light in the P direction.

  The rising mirror 88 includes a reflective surface having frequency selectivity, and reflects DVD and CD standard laser light in the + Y direction, while transmitting BD standard laser light in the -X direction.

  The raising mirror 86 reflects the BD-standard laser light transmitted through the raising mirror 88 in the + Y direction.

  The objective lens 84 focuses the DVD standard and CD standard laser light reflected by the rising mirror 88 on the information recording layer of the disk 80.

  The objective lens 82 sings the BD standard laser light reflected by the rising mirror 86 to the information recording layer of the disk 80.

  Next, the operation of the optical pickup device 10 configured as described above will be described. The reading operation and the writing operation are basically the same, and the writing operation uses laser light having a higher intensity than the reading operation.

  First, the optical path of the laser beam of the DVD standard and the CD standard will be described. Laser light emitted from the laser device 106 is separated into 0th-order diffracted light, + 1st-order diffracted light, and −1st-order diffracted light by the diffraction action of the diffraction grating 110. Here, the laser light emitted from the laser device 106 is linearly polarized light in the S direction.

  The separated laser light is reflected by the reflecting surface of the prism 98, then reflected by the reflectors 94 and 92, and passes through the quarter-wave plate, thereby converting linearly polarized light into circularly polarized light. Is done.

  Thereafter, the laser light converted into circularly polarized light is reflected by the rising mirror 88 and then focused on the information recording layer of the disk 80 by the objective lens 84.

  Laser light, which is return light reflected by the information recording layer of the disk 80, passes through the objective lens 84, is reflected by the rising mirror 88, and passes through the quarter-wave plate. As a result, the laser light that is circularly polarized light is converted into linearly polarized light in the P direction.

  The laser light whose polarization direction has been converted is reflected by the reflectors 92 and 94, passes through the collimator lens 96, passes through the prisms 98 and 100, is given aberration by the anamorphic lens 102, and reaches the PDIC 104. .

  The PDIC 104 reads information and performs focus servo and tracking servo based on the read information.

  Next, the optical path of BD standard laser light will be described.

  First, BD standard laser light, which is linearly polarized light in the S direction, is emitted from the laser device 108. The emitted BD standard laser beam is separated into three laser beams by the diffraction grating 112 and then reflected by the reflecting surface of the prism 100. The reflected laser light passes through the prism 98, is converted into parallel light by the collimator lens 96, is reflected by the reflecting plates 94 and 92, and reaches the quarter wavelength plate 90.

  The laser light converted from the linearly polarized light to the circularly polarized light by the quarter wavelength plate 90 is transmitted through the rising mirror 88 and reflected in the + Y direction by the reflecting surface of the rising mirror 86. The laser beam is focused on the information recording layer of the disk 80 by the objective lens 82.

  The return laser beam reflected by the information recording layer of the disk 80 passes through the objective lens 82 and is reflected by the rising mirror 86, and then passes through the rising mirror 88 and passes through the quarter wavelength plate 90. Is incident on. In the quarter wavelength plate 90, the laser beam of circularly polarized light is converted into the laser beam of linearly polarized light in the P direction. Thereafter, the laser light, which is linearly polarized light in the P direction, is reflected by the reflectors 92 and 94, passes through the collimator lens 96, and then reaches the prism 98.

  BD-standard laser light, which is linearly polarized light in the P direction, passes through the prism 98 and the prism 100, is given aberration by the anamorphic lens 102, and is then irradiated onto the PDIC 104. Then, the PDIC 104 reads information and performs focus servo and tracking servo based on the read information.

  In this embodiment, the optical elements described above are connected by a flexible wiring board. Specifically, among the optical elements described above, the laser device 108 and the PDIC 104 are connected by the single-layer flexible wiring board 26 shown in FIG. Since the laser device 106 needs to pass a large current for the writing operation, the laser device 106 is connected via the flexible wiring board 34 provided with a wide pattern on both sides. Further, the objective lenses 82 and 84 described above are held in a movable state by an actuator, which is connected via a flexible wiring board 38 shown in FIG.

  With reference to FIG. 5 and FIG. 6, the manufacturing method of the optical pick-up apparatus of the above-mentioned structure is demonstrated.

  Referring to FIG. 5, first, each optical component constituting the optical pickup device is incorporated in the housing 28. Specifically, the various optical elements described with reference to FIG.

  Here, the optical elements (laser devices 106 and 108 and PDIC 104 shown in FIG. 4) to be electrically connected are provided in the housing 28 in a state of being connected by the flexible wiring board 26 or the flexible wiring board 34. Furthermore, elements that control these optical elements and elements (resistors, capacitors, coils) for adjusting characteristics and the like are surface-connected to the flexible wiring board 26 via solder. The flexible wiring board 26 has a single-layer wiring structure as described above, and is provided in the housing in a complicated bent state by the bent portion. Note that other optical elements (such as the prism 100 shown in FIG. 4) that are not electrically connected are fixed to predetermined locations inside the housing 28 with an insulating adhesive.

  On the other hand, the actuator 36 is connected to the outside via the flexible wiring board 38 because it is necessary to apply a voltage to the coil for moving the objective lens 33. In addition, the side surface of the actuator 36 to which the flexible wiring board 38 is fixed is disposed at a location that is in close contact with the inner surface of the side wall of the housing 28. Therefore, it is difficult to connect the flexible wiring board 38 to the actuator 36 after the actuator 36 is stored in the storage area 62 of the housing 28.

  Thus, the actuator 36 is stored in the storage area 62 in a state where it is connected to the flexible wiring board 38 in advance. Further, the flexible wiring board 38 is pulled out to the lower surface side of the housing 28 from the opening 29 that opens the housing region 62 of the housing 28. Further, the bottom surface of the actuator 36 is partially exposed to the outside from the opening 29 of the housing 28.

  Next, referring to FIG. 6A, the flexible wiring board 38 drawn to the lower surface of the housing 28 is connected to the flexible wiring board 26 at the connection portion 40. Specifically, the pads of the flexible wiring board 38 and the pads of the flexible wiring board 26 are connected via solder.

  In this step, the flexible wiring board 38 is housed in the concave region 46 of the housing 28, so that the protrusion of the flexible wiring board 38 in the thickness direction is suppressed. Further, the bent portion 50 of the flexible wiring board 38 is disposed in a stepped portion 48 provided on the lower surface of the housing 28. Further, the flexible wiring board 38 is disposed at a predetermined position of the housing 28 by fitting the notch 44 of the flexible wiring board 38 to the protrusion 42 provided on the housing 28.

  Next, referring to FIG. 6B, skew adjustment is performed. Here, the skew adjustment is to make the emitted light and incident light of the laser light focused by the objective lens 76 perpendicular to the disk.

  The structure of the actuator 36 will be described. The actuator 36 includes a base 64 that mechanically supports the whole, a magnet 66 and a suspension holder 72 that are fixed to the base 64, a suspension wire 68 that is held by the suspension holder, and a lens holder 74 that is supported by the suspension wire 68. And an objective lens 76 incorporated in the lens holder 74 and a coil 70 incorporated in the lens holder 74.

  Each coil 70 is connected to the connection portion 54 of the flexible wiring board 38 via two suspension wires 68. Then, tracking servo and focus servo of the objective lens 76 are performed by the interaction between the magnetic field generated from the coil 70 and the magnetic field generated from the magnet 66 when a voltage is applied via the suspension wire 68.

  In this embodiment, the overall position of the actuator 36 is adjusted so that the traveling direction of the laser light passing through the objective lens 76 becomes a predetermined direction and the objective lens 76 focuses the laser light at a predetermined position. Here, the position adjustment includes not only position adjustment in the X direction, Y direction, and Z direction, but also angle adjustment around each axis. In this embodiment, this position adjustment and angle adjustment are performed by moving or tilting the entire actuator 36.

  When the skew adjustment is completed, an adhesive such as an epoxy resin is applied between the actuator 36 and the housing 28 and cured to fix the actuator 36. Similarly, the flexible wiring board 38 is bonded to the housing 28 via an adhesive.

  Here, the skew adjustment may be performed after the position adjustment of an optical element such as a laser device or a PDIC, or may be performed before these steps.

  As described above, in the skew adjustment, the actuator 36 is moved and tilted as a whole. Therefore, the flexible wiring board 38 fixed to the right side surface of the actuator 36 is also affected by this movement and inclination. From this, if the flexible wiring board 38 is flat, especially when the actuator 36 is rotationally adjusted, a stress that twists the flexible wiring board 38 acts. Furthermore, the flexible wiring board 38 may be deformed so as to bulge outward.

  In this embodiment, a stepped bent portion 50 is provided in the middle of the flexible wiring board 38. Therefore, even when the actuator 36 moves or tilts due to the skew adjustment, the bent portion 50 is deformed to be absorbed. Therefore, no stress remains on the flexible wiring board 38 due to the movement of the actuator 36. Furthermore, the flexible wiring board 38 is also prevented from being deformed so as to swell outward.

  Further, when the flexible wiring board 38 is flat, the fixed flexible wiring board 38 may hinder the movement of the actuator 36 during skew adjustment. In the present embodiment, the bent portion 50 is deformed to allow the actuator 36 to move or tilt. Therefore, this embodiment has an advantage that the actuator 36 can be smoothly moved in the skew adjustment.

  When the above steps are completed, an optical pickup device as shown in FIG. 1 is manufactured through confirmation steps such as confirmation of the position of each optical element.

DESCRIPTION OF SYMBOLS 10 Optical pick-up apparatus 11 Wiring part 14 Wiring pattern 22 Package 26 Flexible wiring board 28 Housing 29 Opening part 30 Guide hole 32 Guide groove 33 Objective lens 34 Flexible wiring board 36 Actuator 38 Flexible wiring board 40 Connection part 42 Projection part 44 Notch part 46 Concave area 48 Stepped part 50 Bent part 52 Connection part 54 Connection part 56 Wiring part 58 Wiring part 60 Bending part 62 Storage area 64 Base 66 Magnet 68 Suspension wire 70 Coil 72 Suspension holder 74 Lens holder 76 Objective lens 80 Disc 82 Objective lens 84 Objective lens 86 Rising mirror 88 Rising mirror 90 1/4 wavelength plate 92 Reflecting plate 94 Reflecting plate 96 Collimating lens 98 Prism 100 Prism 102 Anamo lens 04 PDIC
106 Laser device 108 Laser device 110 Diffraction grating 112 Diffraction grating

Claims (9)

A housing having a first main surface and a second main surface;
An actuator that holds the objective lens movable;
A flexible wiring board electrically connected to the actuator,
An optical pickup device, wherein a bent portion obtained by bending a middle portion of the flexible wiring board is disposed at a step portion in which the second main surface of the housing has a step shape.   2. The optical pickup device according to claim 1, wherein the flexible wiring board is housed in a concave region in which the second main surface of the housing is partially recessed. The actuator is incorporated into the housing such that a part of the actuator is exposed from the first main surface side to the second main surface.
3. The optical pickup device according to claim 1, wherein the flexible wiring board is routed from the second main surface side to the inside of the housing and connected to the actuator. 4.   The cutout portion in which the flexible wiring board is partially provided is fitted into a protrusion portion in which the second main surface of the housing is partially protruded. An optical pickup device according to claim 1.   5. The optical pickup device according to claim 1, wherein the flexible wiring board is fixed to the second main surface of the housing via an insulating adhesive.   6. The optical pickup device according to claim 1, wherein an end portion of the flexible wiring board is connected to a main board. A method of manufacturing an optical pickup device that emits laser light to an information recording medium and detects the laser light reflected by the information recording medium,
Preparing a housing having a first main surface and a second main surface, and incorporating an actuator for movably holding the objective lens into the housing while being connected to the flexible wiring board;
Adjusting the position of the actuator while radiating the laser light to the objective lens, and
In the step of incorporating, the bent portion provided in the middle part of the flexible wiring board is disposed in the stepped portion provided in the second main surface of the housing,
In the step of adjusting the position, the bent portion of the flexible wiring board is deformed along with the adjustment of the position of the actuator.   8. The method of manufacturing an optical pickup device according to claim 7, wherein after the step of adjusting the position is completed, the flexible wiring board is fixed to the housing via an adhesive. 9. The method of manufacturing an optical pickup device according to claim 7, wherein, in the step of adjusting the position, the flexible wiring board is connected to a main board.

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