JPH0728580Y2 - Objective lens drive - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention irradiates an optical recording medium such as an optical disc for recording information signals such as audio signals and video signals with a light beam and records the optical recording medium on the optical recording medium. The present invention relates to an objective lens driving device used for an optical pickup device or the like of a recording and / or reproducing device for reproducing the information signal or recording the information signal on the optical recording medium.

[Conventional technology]

Conventionally, a recording and / or reproducing apparatus such as an optical disc player that records and / or reproduces an information signal on an optical recording medium using a light beam such as a laser beam irradiates the optical recording medium with the light beam. An optical pickup device that detects a return light beam from the optical recording medium is used.

In this optical pickup device, a light beam emitted from a light source such as a semiconductor laser is accurately focused on a signal recording surface of an optical disc that is rotated at high speed, and a recording track of the optical disc is accurately tracked. An objective lens driving device is provided for performing tracking control and focusing control for driving and displacing an objective lens for focusing the light beam on the signal recording surface of the optical disc in a focusing direction parallel to the optical axis and a tracking direction orthogonal to the optical axis. ing.

An optical pickup device used in the recording and / or reproducing device has an objective lens on an optical system block having a built-in semiconductor laser, in which the objective lens is in a direction parallel to the optical axis and in a direction orthogonal to the optical axis. An objective lens driving device for driving and displacing to perform tracking and focusing control is attached.

As this objective lens driving device, a device configured as shown in FIGS. 13 and 14 is used. The objective lens driving device shown in FIGS. 13 and 14 has a circular arc shape on a mounting substrate 1 made of a high magnetic permeability material such as soft iron, which is a mounting portion for an optical system block and constitutes a yoke of a magnetic circuit portion. A pair of fan-shaped first outer peripheral yokes that are curved
22 and a pair of inner peripheral side yokes 3, 3 are arranged at a predetermined interval so as to face each other to form a magnetic gap, and a focusing magnet 4, below the outer peripheral side yokes 2, 2. 4 is provided, and a magnet for tracking is provided on the surfaces of the pair of second outer peripheral yokes 5, 5 which are erected so as to be located between the outer peripheral yokes 2, 2.
The magnetic circuit unit 7 is formed by combining 6 and 6 together.

A spindle 8 is erected so as to be located at the center of the magnetic circuit section 7 on the mounting substrate 1 in which the magnetic circuit section 7 is constructed as described above. On this support shaft 8, a cylindrical bobbin 11 having an objective lens 10 held by a lens barrel 9 separated from the axial center, that is, attached at an eccentric position is rotated via a cylindrical boss portion provided at the axial center. Displaceable and further the above-mentioned support shaft 8
Is supported so as to be slidable in the axial direction. The bobbin 11 thus supported by the support shaft 8 is a rubber that is elastically displaceable so that the optical axis of the objective lens 10 and the optical axis of the optical system block coincide with the tracking direction at the neutral point, which is the inoperative state position. It is held by an elastic holding member 12 made of a material or the like. The elastic holding member 12 is attached by bonding the base end portion bent in an L shape to the attachment substrate 1 or the like. On the other hand, a support pin 13 is vertically attached to the bobbin 11 at a position symmetrical with respect to the objective lens 10 about the spindle 8.
The bobbin 11 is held at the neutral point as described above by fitting and supporting the lower end portion of the support pin 13 in the fitting hole 14 formed in the holding portion of the elastic holding member 12.

As described above, on the outer peripheral surface of the bobbin 11 supported by the support shaft 8 and the elastic holding member 12, the bobbin 11 is slidably displaced in the axial direction to drive the objective lens 10 in the focusing direction, and the focusing drive coil 15 and the above-mentioned. A tracking drive coil 16 is provided which rotationally displaces the bobbin 11 around the axis to rotationally drive the objective lens 10 in the tracking direction. The focusing drive coil 15 is wound so as to generate a driving force for driving the bobbin 11 in the axial direction of the support shaft 8 in combination with the direction of the magnetic field of the focusing magnets 4, 4, and the tracking drive coil 16 is wound. Is wound so as to generate a driving force for driving the bobbin 11 around the support shaft 8 in combination with the direction of the magnetic field of the tracking magnets 6, 6.

Further, on the lower surface side of the mounting substrate 1, when the objective lens driving device is attached to the optical block, the optical axis of the objective lens 10 and the optical axis of the light beam transmitted through the optical system block can coincide with each other. A ring-shaped positioning adjusting member 17 for adjusting and positioning the mounting position of the driving device with respect to the optical block is mounted by a screw 18. The positioning adjustment member 17 is eccentrically attached to the support shaft 8, and is fitted into the positioning recess of the optical system block when the objective lens driving device is attached to the optical system block. By rotationally adjusting the positioning adjustment member in the positioning recess, the alignment between the objective lens and the optical axis of the light beam is achieved.

The objective lens driving device configured as described above uses the servo currents corresponding to the error detection outputs in the focusing direction and the tracking direction, which are obtained by detecting the returning light beam reflected from the optical disc surface, to the driving coils 15 and 16 respectively. Is selectively supplied to drive the bobbin 11 in the axial direction and the axial direction of the support shaft 8 to move and displace the objective lens 10 in the focusing direction and the tracking direction and focus on the signal recording surface of the optical disc. The beam spot of the light beam is controlled so as to accurately follow and match the recording track of the optical disc.

[Problems to be solved by the invention]

In the objective lens driving device configured as described above, the bobbin 11 in which the objective lens 10 is attached in a decentered position is used.
Has no fixed support point because it is configured to be slidably rotated around the support shaft 8 provided at the shaft center. Therefore, resonance may occur when driving and displacing the bobbin 11 in the focusing direction and the tracking direction, and the moving displacement of the objective lens 10 according to the error detection output in the focusing direction and the tracking direction cannot be performed, and the light beam There is a possibility that focusing on the signal recording surface of the optical disc and tracking scanning of the recording track cannot be performed.

Further, since the bobbin 11 is slidably displaced in the axial direction of the support shaft 8, so-called stick slip occurs during driving, and smooth movement displacement in the axial direction of the support shaft 8 cannot be realized.

Further, since the optical axis of the objective lens and the optical axis of the light beam are accurately aligned with each other, the mounting accuracy of the support shaft 8 for supporting the bobbin 11 is required, and the bobbin 11 is smooth against the support shaft 8 without rattling. Therefore, the dimensional accuracy of the shaft diameter of the support shaft 8 and the hole diameter of the insertion hole through which the support shaft 8 is inserted must be processed with high accuracy, and the processing is extremely difficult.

Furthermore, in the objective lens driving device, a positioning member 17 is mounted on the lower surface of the mounting substrate 1 in order to position the mounting position on the optical block. The positioning member 17 and the bobbin 11 sandwich the mounting substrate 1 therebetween. Since it is necessary to attach from two directions, the assembly process becomes complicated.

Therefore, it is an object of the present invention to provide an objective lens driving device which does not cause resonance during driving and can perform accurate focus control and tracking control with high response even with a high frequency servo current.

Furthermore, the present invention reduces the number of parts, facilitates assembly, and manages the dimensional accuracy of each component, and facilitates alignment of the optical axis of the objective lens with the optical axis of the optical block during assembly. It is an object of the present invention to provide an objective lens driving device that can be accurately performed.

[Means for Solving the Problems]

In order to achieve the above-mentioned object, the objective lens driving device according to the present invention includes a bobbin to which the objective lens is attached, a direction in which the bobbin is parallel to the optical axis of the objective lens, and a direction perpendicular to the optical axis. And a hinge portion made of a synthetic resin that is displaced in a direction orthogonal to the optical axis of the objective lens, and one end of the hinge portion is rotatable with respect to the substrate in a direction orthogonal to the optical axis. A supporting member that is supported, and a pair of leaf springs that support the bobbin at one end side such that the bobbin can move in parallel in a direction parallel to the optical axis of the objective lens and that the other end side is attached to the supporting member. On the substrate, the bobbin, together with the support member and the leaf spring, is configured to be driven and displaced in the direction orthogonal to the optical axis of the objective lens with the hinge portion as a displacement portion. .

[Action]

In the objective lens driving device according to the present invention, when the servo signal in the focusing direction for driving the electromagnetic driving means in a direction parallel to the optical axis of the objective lens is supplied, the bobbin to which the objective lens is attached is provided with a pair of leaf springs. Is used as a displacement portion and is translated in a direction parallel to the optical axis of the objective lens.

Further, when a servo signal in the tracking direction for driving the electromagnetic driving means in a direction orthogonal to the optical axis of the objective lens is supplied, the bobbin uses the hinge portion made of synthetic resin provided on the support member as a displacement portion for the objective. The lens is moved and operated in the direction orthogonal to the optical axis of the lens.

Further, the optical axis position of the objective lens is adjusted by rotationally adjusting a support member whose one end is rotatably supported with respect to the substrate in a direction orthogonal to the optical axis of the objective lens. Be seen.

〔Example〕

Hereinafter, a specific embodiment of the present invention will be described with reference to the drawings.

Prior to the description of specific embodiments of the objective lens driving device according to the present invention, a specific configuration of the objective lens driving device as a reference prior to the present invention will be described.

As shown in FIGS. 1 and 2, this objective lens driving device is a mounting substrate that serves as a mounting portion to an optical system block (not shown) containing a semiconductor laser as a light source for emitting a light beam and other optical components. First and second yokes 22 and 23 having a substantially U-shape and constituting a magnetic circuit portion are mounted on 21 so as to face each other. These yokes 22 and 23 are connected to each other by the connecting portion 22.
Positioning protrusions 27 are formed by fitting the a and 23a sides into the positioning grooves 24 provided in the mounting substrate 21 and fitting recesses 25 and 26 provided on the lower surfaces of the connecting portions 22a and 23a into the positioning grooves 24. , 27 are fitted and attached (see FIG. 3), and the attachment direction and the attachment position with respect to the attachment substrate 21 are positioned and fixed. Rising pieces 22b, 2 located outside each yoke 22, 23
Magnets 28, 28 are arranged so as to be joined to the inner surface of 3b, respectively.

In addition, the mounting substrate 21 has the first and second yokes 22, 23.
An optical window 29 through which the light beam emitted from the semiconductor laser incorporated in the optical system block is transmitted is provided so as to be located in the center of the space. Further, on both sides of the mounting board 21, mounting tongue pieces 30, 3 serving as fixing parts to the optical system block are provided.
0 is drilled. These mounting tongue pieces 30 and 30 are provided with screw insertion holes 31 and 31, and the mounting substrate 21 is fixed to the optical system block by fixing screws 32 and 32 which are inserted through these screw insertion holes 31 and 31. It

The objective lens 33, which is disposed so as to face the optical disc that is the optical recording medium and focuses the beam spot of the light beam on the signal recording surface of the optical disc, is a cylindrical lens tube having a flange portion 34 provided on the outer periphery. It is attached to a bobbin 36 having a rectangular shape via 35. This bobbin 36 is made of synthetic resin and has a fitting hole into which the lens barrel 35 is tightly fitted in the central portion.
37 has been drilled. Then, the lens barrel 35 is attached by fitting the lower end side thereof into the fitting hole 37. Bobbin 36 above
On the outer peripheral surface of the objective lens 33, a focusing drive coil 38 for obtaining a driving force for driving and displacing the objective lens 33 in a focusing direction that is a direction parallel to the optical axis of the objective lens 33, Four tracking drive coils 39 are provided to obtain a driving force for driving and displacing in the radial direction of the optical disc in the direction orthogonal to the axis. The focusing drive coil 38 is wound in the circumferential direction of the bobbin 36 so as to generate a driving force for driving the objective lens 33 in the focusing direction in cooperation with the magnetizing directions of the magnets 28, 28, and each of the tracking The drive coil 39 is coupled with the magnetizing direction of the magnets 28, 28 to make the objective lens 33
Is wound in a rectangular shape so as to generate a driving force for driving the bobbin in the tracking direction, and is provided over each corner portion of the bobbin 36.

The bobbin 36 to which the objective lens 33 is attached and the focusing and tracking drive coils 38 and 39 are provided as described above is fixed at the base end side to the support member 40 fixed to the attachment substrate 21 via the second yoke 23. It is supported by a pair of leaf springs 41, 41 attached together. The support member 40 to which the leaf springs 41 are fixed is formed by molding synthetic resin or the like, and faces the second yoke 23 of the leaf spring mounting portion 42 having plate-shaped upper and lower end surfaces 42a and 42b parallel to each other. Opposite to the outer side surface side of the rising piece to which the magnet 28 of the second yoke 23 is joined via the continuous portion 43 provided on one side surface so as to be orthogonal to the height direction of the leaf spring mounting portion 42. A pair of L-shaped holding pieces 44, 44 provided in the above-described manner, are provided in series with a fitting piece 45 that is fitted and held. And this support member 40,
The connecting portion 43 is inserted into the gap between the sandwiching pieces 44, 44, the fitting piece 45 is fitted between the sandwiching pieces 44, 44, and is attached to the second yoke 23. Support member attached in this way
40 is separated from the mounting board 21 and is fixed to the mounting board 21 via a second yoke 23 fixed to the mounting board 21. The continuous portion 43 of the support member 40 has the continuous portion
A hinge portion 46, which is formed by thinning a part of 43, is provided continuously in the height direction. In this way the hinge part 46
By providing the above, the objective lens 33 attached to the bobbin 36 can be displaced in the direction orthogonal to the optical axis of the objective lens 33 about the hinge portion.

Then, the pair of leaf springs 41, 41 are provided on the upper and lower end surfaces 42a, 42b of the leaf spring mounting portion 42 of the supporting member 40, respectively, at the base end portions 41a, 41a.
Can be fixed. In these base end portions 41a, 41a,
Fitting holes 48 that fit into fitting projections 47 that are respectively provided on the upper and lower end surfaces 42a and 42b of the leaf spring attachment portion 42 that are parallel to each other are provided. Then, the leaf springs 41, 41 have the fitting holes 48.
Is fitted and attached to the fitting protrusion 47. At this time, the fitting protrusion 47 is heated and crushed, and the leaf springs 41, 4 are
The leaf spring mounting portion 42 of 1 is prevented from coming off and is fixed. The pair of leaf springs 41, 41 attached in this way are
They are parallel to each other and to the surface of the mounting substrate 21.

At the center of the pair of leaf springs 41, 41, the second yoke 23 faces when attached to the leaf spring attachment portion 42, and an opening 49 for adjusting the elastic force is provided.

Then, the bobbin 36 is attached with the upper and lower surfaces 51 and 52, which are planes orthogonal to the optical axis of the objective lens 33, being sandwiched by the bobbin attaching portions 50 and 50 provided on the tip ends of the pair of leaf springs 41 and 41. The bobbin mounting portions 50, 50 are respectively provided with a through hole 53 facing the objective lens 33 mounted on the bobbin 36 and a through hole 54 facing the optical window 29 opened in the mounting substrate 21. Further, around the through holes 53, 54, there are formed fitting holes 56 into which the fitting protrusions 55 formed on the upper and lower surfaces 51, 52 of the bobbin 36 fit. The bobbin 36 has the fitting protrusions 55 with the fitting holes.
56, the fitting protrusion 55 is crushed to prevent it from coming off, and is supported and fixed to the bobbin mounting portions 50, 50 of the leaf springs 41, 41. In addition, the bobbin 36 includes a first yoke and a second yoke.
Rising pieces 22b, 23b to which magnets 28, 28 of 22, 23 are joined
Yoke insertion holes 57, 58 through which the inner rising pieces 22c, 23c facing each other are inserted, and the inner rising pieces of the respective yokes 22, 23 are supported by the leaf springs 41, 41. 22c and 23c are inserted and fitted. Then, the focusing and tracking drive coils 38, 39 provided on the bobbin 36 are
A predetermined magnetic gap is held and supported in the gap between the inner rising pieces 22c and 23c of the yoke 28 and the yokes 22 and 23.

The lens barrel 35 holding the objective lens 33 attached to the bobbin 36 is fitted into the fitting hole 37 while the bobbin 36 is supported by the pair of leaf springs 41, 41, and the flange portion 34 is provided on one side. The flat spring 41 is locked and attached to the smooth surface of the flat spring 41, and the objective lens 33 is positioned in the optical axis direction.

In the objective lens drive configured as described above, when a driving current is supplied to the focusing drive coil 38, this coil is driven.
A force in the direction of arrow F in FIG. 1 is generated by the magnetic action from the direction of the current flowing in 38 and the direction of the magnetic flux from the magnet 28, and the bobbin 36 is driven in the same direction. At this time, bobbin
The pair of parallel leaf springs 41, 41 supporting the 36 exert moments in directions opposite to each other.
If ones having the same compliance are used for 1,41, the moments cancel each other and move while maintaining the parallel state, and move the bobbin 36 in the direction parallel to the optical axis direction of the objective lens 33. Then, the focus control of the objective lens 33 that focuses the light beam on the signal recording surface of the optical disc is performed.

When a drive current is supplied to the tracking drive coil 39, the direction of the current flowing in the coil 39 and the magnet
A force in the direction of arrow T in FIG. 1 is generated by the magnetic action from the direction of the magnetic flux from 28, and the bobbin 36 is driven in the same direction around the hinge portion 46 of the support member 40 supporting the bobbin 36. . Then, the objective lens 33 is moved in a direction orthogonal to the optical axis direction parallel to the signal recording surface of the optical disc, and tracking control is performed.

In the above-mentioned objective lens driving device, the support member 40 is mounted by fitting the fitting piece 45 between the holding pieces 44, 44 provided on the second yoke 23. However, the holding pieces 44, 44 should be provided. Without
As shown in FIG. 4, the fitting piece 45 may be attached to the outer rising surface of the second yoke 23 by bonding with an adhesive or the like.

Further, the support member 40 is fixed to the mounting substrate 21 via the second yoke 23, but via a support shaft which is erected on the mounting substrate 21 like the objective lens driving device according to the present invention described below. It may be attached.

Hereinafter, a supporting member using the support shaft 60 that is planted on the mounting substrate 21
A specific embodiment of the present invention in which 40 is attached and an optical axis adjusting mechanism 63 is further provided will be described.

The same parts as those of the objective lens driving device shown in FIGS. 1 to 3 are designated by the same reference numerals and detailed description thereof will be omitted.

In the objective lens driving device shown in FIGS. 5 and 6, a support shaft 60 for rotatably supporting the support member 40 is planted on a mounting substrate 21 on which the first and second yokes 22 and 23 are mounted. To do. The support shaft 60 is a second yoke that constitutes a magnetic circuit section.
It is planted on the outer side of 23. The supporting member 40 supported by the mounting substrate 21 via the support shaft 60 supports the bobbin 36 to which the objective lens 33 is mounted as shown in FIGS. 7 (A), (B) and (C). A plate-shaped leaf spring mounting portion 42 having upper and lower end surfaces 42a and 42b parallel to each other to which the base end portions 41a and 41a of the pair of leaf springs 41 and 41 are fixed, and a second yoke of the leaf spring mounting portion 42. 23 and a fixing portion 62 having a support shaft fitting hole 61 provided through a continuous portion 43 provided so as to be orthogonal to the height direction on one side surface facing 23. The continuous portion 43 is provided at the center position of the leaf spring attachment portion 42, and is provided with a hinge portion 46 which is continuous in the height direction and is partially thinned. Also,
At the position eccentric with respect to the support shaft fitting hole 61 on the lower end surface of the fixed portion 62, an optical axis alignment is performed to perform alignment adjustment between the optical axis of the objective lens 33 and the optical axis of the light beam transmitted from the optical system block. mechanism
An engagement pin 66 that engages with an engagement recess 65 provided in the rotation adjusting member 64 of 63 is provided in a protruding manner.

The support member 40, to which the pair of leaf springs 41, 41 supporting the bobbin 36 with the objective lens 33 fixed, is fixed, is fitted with a support fitting hole 61 formed in the fixing portion 62 into the support shaft 60 by press fitting. twenty one
Mounted on.

Further, on the mounting substrate 21, the objective lens 33 and the optical axis alignment mechanism 63 for aligning the optical axis of the light beam are provided as described above. The optical axis adjusting mechanism 63 has a through hole 68 provided at a position eccentric with respect to a fitting recess 67 that is fitted to a flange portion 60a formed at the base end portion of the support shaft 60 and fixed to the mounting substrate 21 by screwing. It is configured by a rotation adjusting member 64 which is inserted through the service screw 69 and is eccentrically rotated with respect to the support shaft 60. An engaging concave portion 65 is provided at one end of the rotation adjusting member 64 facing the through hole 68, and an engaging pin 66 protruding from the supporting portion 40 is engaged with the engaging concave portion 65. A gear portion 70 is formed on the outer peripheral surface of the rotation adjusting member 64. Then, as shown in FIG.
When rotating the adjustment driver D with
40 is rotated about a support shaft 60. The objective lens 33 attached to the bobbin 36 supported by the support member 40 by the two leaf springs 41, 41 is a light beam which is rotated in the direction of arrow A in FIG. The optical axis is aligned with the optical axis of. Then, when the optical axis is aligned, the fixing screw 69 is tightened and the rotation adjusting member 64 is fixed to the mounting substrate 21, so that the objective lens 33 and the optical axis of the light beam are accurately aligned. The device is configured.

In the objective lens drive configured as described above, even if the hinge portion 46 has a variation in processing accuracy and the objective range 33 and the optical axis of the light beam are deviated, the hinge portion 46 has a variation in processing accuracy. It becomes possible to absorb the light and perform the optical axis alignment with high accuracy.

Although the support member 40 is press-fitted and attached to the support shaft 60 in the above embodiment, a retaining ring may be fitted to the tip of the support shaft 60 to prevent the support member 40 from coming off.

Further, instead of the support shaft 60, a long screw may be inserted into a support shaft fitting hole 61 formed in the fixing portion 62, and the support member 40 may be attached by this screw.

In the structure shown in FIGS. 5 and 6 described above, the optical axis alignment mechanism 63 is configured by providing the rotation adjusting member 64 which is separate from the support member 40. As shown in FIG. 10, an arc-shaped fixing screw insertion hole 70 centered on the rotation center of the fixing portion 62 of the support member 40 is formed at a position eccentric from the rotation center. Support member 40 within the range of insertion hole 70
Alternatively, the objective lens 33 and the optical axis of the light beam may be adjusted by rotating. That is, the hinge portion 46 serving as a rotation center when the objective lens 33 supported by the support member 40 via the pair of leaf springs 41, 41 is rotationally displaced in the direction orthogonal to the optical axis thereof is provided continuously. On the lower surface of the fixed portion 62 located on the extension line of the portion 43, a support pin 72 that fits into a fitting recess 73 formed in the mounting substrate 21 is provided in a protruding manner. A fixing screw insertion hole 70 having a circular arc centered on the support pin 72 is formed at a position eccentric from the support pin 72. Then, the support member 40 is rotated around the support pin 72 in a state where the support pin 72 is fitted into the fitting recess 73 and the fixing screw 74 inserted into the fixing screw insertion hole 70 is screwed into the mounting substrate 21. The objective lens 33 is moved to the
The optical axis is aligned with the optical axis of the light beam by being rotated in the direction of arrow A in FIG. Then, when the objective lens 33 and the optical axis of the light beam are aligned, they are fixed by the fixing screw 74 to obtain an objective lens driving device in which the optical axis is aligned accurately.

In the above-described embodiment, the pair of leaf springs 41, 41 has the fitting holes 48 formed in the respective base end portions 41a, 41a protruding from the upper and lower end surfaces 42a, 42b of the leaf spring mounting portion 42 of the supporting member 40. Fitting protrusion 4 installed
The plate springs 41, 41 are clamped by the pair of nut plates 85, 86 by the pair of nut plates 85, 86, as shown in FIGS. 11 and 12. Then, the screw 88 is inserted through the through hole 87 formed in the leaf spring attachment portion 42, and the leaf springs 41, 41 are attached to the leaf spring attachment portion 42 by the screw 88 and the nut plates 85, 86. You may do it.

In each of the above-described embodiments, an example in which only the objective lens 33 is attached to the bobbin 36 that is the movable portion is given, but a beam splitter, a photodetector, and other optical components are attached to the bobbin 36. Is also applicable.

[Effect of device]

As described above, in the objective lens driving device according to the present invention, the bobbin to which the objective lens is attached is movably supported by a pair of leaf springs in a direction parallel to the optical axis of the objective lens. The objective lens can be accurately moved in a direction parallel to the optical axis direction without causing tilt, and smooth movement is realized. Furthermore, since the bobbin is movably supported by a hinge portion made of synthetic resin in a direction orthogonal to the optical axis of the objective lens,
Resonance hardly occurs during driving, and stable tracking operation can be realized.

In particular, a pair of leaf springs supporting the objective lens is attached, and one end side of a supporting member having a hinge portion made of a synthetic resin which is displaced in a direction orthogonal to the optical axis of the objective lens is attached to Since it is rotatably supported in the direction orthogonal to the axis, the optical axis position of the objective lens can be adjusted by rotationally adjusting the support member around the support point for the substrate. At times, the optical axis of the objective lens and the optical axis of the optical block side can be easily and accurately aligned.

[Brief description of drawings]

FIG. 1 is a perspective view showing an example of an objective lens driving device prior to the present invention, FIG. 2 is an exploded perspective view thereof, and FIG. 3 is a side sectional view. FIG. 4 is a perspective view showing another example of the mounting state of the support member to the yoke. FIG. 5 is a perspective view showing an embodiment of the objective lens driving device according to the present invention, FIG. 6 is a perspective view showing its assembled state, and FIG. 7 shows a supporting member used in this embodiment. FIG. 7 (A) is a front view thereof,
FIG. 7 (B) is a plan view and FIG. 7 (C) is a side view. FIG. 8 is a plan view showing the optical axis position adjustment state of the objective lens. FIG. 9 is a perspective view showing another example of a supporting member having an optical axis adjusting mechanism for the objective lens, and FIG. 10 is a plan view showing an optical axis position adjusting state of the objective lens having the supporting member. is there. FIG. 11 is an exploded perspective view showing another example of a mounting structure of a leaf spring to a support member, and FIG. 12 is a perspective view showing its assembled state. FIG. 13 is a perspective view showing a conventional example, and FIG. 14 is a side sectional view thereof. 21 …… Mounting board 22 …… First yoke 23 …… Second yoke 28 …… Magnet 33 …… Objective lens 36 …… Bobbin 38 …… Focusing drive coil 39 …… Tracking drive coil 40 …… Supporting member 41 ...... Leaf spring 42 …… Leaf spring mounting part 45 …… Mating piece 46 …… Hinge part 60 …… Spindle 61 …… Spindle fitting hole

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Tomokazu Ishida 6-735 Kita-Shinagawa, Shinagawa-ku, Tokyo Sony Corporation (72) Kenji Shintani 6-35 Kita-Shinagawa, Shinagawa-ku, Tokyo Within Sony Corporation (56) References JP-A-60-160032 (JP, A) JP-A-58-182141 (JP, A) Actually developed 59-14134 (JP, U)

Claims (1)

[Scope of utility model registration request] 1. A bobbin to which at least an objective lens is attached, electromagnetic driving means for driving the bobbin in a direction parallel to the optical axis of the objective lens and in a direction orthogonal to the optical axis, and an optical axis of the objective lens. A support member having a hinge portion made of a synthetic resin that is displaced in a direction orthogonal to each other, one end of which is supported rotatably in a direction orthogonal to the optical axis with respect to the substrate; The pair of leaf springs are supported so as to be movable in parallel in a direction parallel to the optical axis of the lens, and the other end side is attached to the support member, and the bobbin on the substrate together with the support member and the leaf spring. An objective lens driving device which is driven and displaced in a direction orthogonal to an optical axis of the objective lens with the hinge portion as a displacement portion.