JP2000067444A - Objective lens driving device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an objective lens driving device in which the position of a light spot on an optical disk recording surface is not displaced even though the lens is tilted in the radial direction of the disk in accordance with the tilt of the disk. SOLUTION: The moving section of the objective lens driving device consists of an objective lens 1, a lens holder 2, focusing coils 3, tracking coils 4 and tilting coils 5. The objective lens 1 and the parts constituting of the moving section and an elastic supporting member 8 elastically supporting moving parts are arranged so that a main point position S, which is the optical center of the lens 1, and the tilt operation center position of the entire moving section, on which the lens 1 is arranged, are approximately made to coincide with each other.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an objective lens driving device used for an optical disk device.

[0002]

2. Description of the Related Art An example of an objective lens driving device and an optical system used in an optical disk device is disclosed in, for example, JP-A-6-2.
The thing described in 51405 gazette is known.

FIGS. 14 to 16 show the structure of a basic objective lens driving device. FIG. 14 is a cross-sectional view of the objective lens driving device in the tangential direction of the optical disk, and FIG.
5 is a side view of the objective lens driving device, and FIG. 16 is a transverse sectional view of the objective lens driving device in a radial direction of the optical disk.

An objective lens 1 is disposed on an upper surface of a lens holder 2, a focusing coil 3 is wound on a side surface of the lens holder 2, and a tracking coil 4 and the objective lens 1 are mounted on a side surface of the lens holder 2 in a radial direction of the optical disk. A tilting coil 5 for tilting drive is attached to the. 4
The one parallel linear elastic support member 8 has one end fixed to the lens holder 2 and the other end fixed to the fixed portion.
Is movable elastically in the focusing direction and in the tracking direction, and is also elastically supported in such a manner that it can be tilted in the radial direction of the optical disk.

On the other hand, a magnetic circuit composed of a yoke 7 and a magnet 6 is disposed on a fixed portion to which one end of the elastic support member 8 is fixed, and a driving circuit that flows through the focusing coil 3, the tracking coil 4 and the tilting coil 5. The current acts on the magnetic flux generated from the magnetic circuit. An inclination detector 9 (9a, 9b) for detecting the inclination of the optical disc is arranged on the upper surface of the lens holder 2 on which the objective lens 1 is arranged.

At the time of focusing control, an electric current is appropriately supplied to the focusing coil 3 in accordance with the runout of the recording surface of the optical disk, and the objective lens 1 is operated in the optical axis direction.
The light beam spot can follow the recording surface of the optical disk. At the time of tracking control, an appropriate current is supplied to the tracking coil 4 in accordance with the eccentricity and meandering of the track of the optical disc to operate the objective lens 1 in a direction perpendicular to the optical axis, and the spot of the light beam is moved to the track of the optical disc. You can follow up. Further, with respect to the tilt of the optical disk, it is possible to appropriately supply a current to the tilt coil 5 based on the signal from the tilt detector 9 and to tilt and drive the objective lens 1 in accordance with the tilt of the optical disk.

[0007]

In recent years, higher recording densities have been promoted in optical disk devices. One method for realizing higher recording density is to narrow the light beam more narrowly and reduce the spot diameter on the recording surface of the optical disk. The spot diameter is λ, the wavelength of the light beam,
If the numerical aperture of the objective lens 1 is NA, it is proportional to (λ / NA). Therefore, in general, a method of narrowing down the light beam and increasing the recording density by reducing the wavelength λ of the light beam and setting the numerical aperture NA of the objective lens 1 to a larger value than in the past is mainly used. Has become.

By increasing the NA of the objective lens 1, it is possible to narrow the light beam more narrowly, but on the other hand, there is a characteristic that the optical characteristic deterioration due to the inclination between the optical disk and the objective lens 1 becomes remarkable. Therefore, it is necessary to suppress the inclination angle between the optical disk and the objective lens 1 to a certain value by some means.

In the prior art objective lens driving device,
As shown in FIGS. 14 to 16, the tilt detector 9 detects the relative tilt angle between the optical disk and the objective lens 1, and appropriately supplies a current to the tilt coil 5 based on the detection result. 1 and the optical disk were kept at a constant tilt angle.

However, in the case of this objective lens driving device, as shown in FIG. 16, when a driving current is supplied to the tilting coil 5, the movable portion on which the objective lens 1 is disposed is moved to its center of gravity G or four elastic supporting members. The tilting operation is performed with the support center P determined by the rigidity balance of the tilting center as the tilting center. Therefore, the objective lens 1 disposed near the upper surface of the lens holder 2 distant from the center of gravity G of the movable portion or the support center P is displaced in the radial direction of the optical disk, that is, in the tracking direction due to the tilting operation.

Since the principal point position S, which is the optical center of the objective lens 1, does not coincide with the tilt center position,
When the objective lens 1 is displaced in the tracking direction due to the tilting operation, the principal point position S of the objective lens 1 is also displaced, and as a result, the light spot position on the recording surface of the optical disc is also displaced in the tracking direction.

Therefore, the displacement amount of the light spot becomes a disturbance to the tracking control system, and it becomes impossible to cause the light spot position to correctly follow the track of the optical disk. As a result, a signal is accurately read from the optical disk, or It becomes difficult to write.

As described above, the configuration of the conventional objective lens driving device described above is such that the tilting in the radial direction of the optical disk is performed around the center of gravity G of the movable part or the support center position P determined by the rigidity balance of the four elastic support members. The operation is performed, and the principal point position S, which is the optical center of the objective lens 1, and the tilt center position in the radial direction of the optical disc do not match.

Therefore, when the objective lens 1 is tilted in accordance with the tilt of the optical disk so as to keep the relative tilt angle between the optical disk and the objective lens 1 constant, the objective lens 1 focuses on the optical disk recording surface. The light spot is displaced in the tracking direction. As a result, the amount of displacement of the light spot in the tracking direction due to this tilting operation becomes a disturbance to the tracking control system, and there has been a problem that signals cannot be read or written from the optical disk accurately.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problem. Even if the objective lens is tilted in accordance with the tilt of the optical disk, the position of the light spot on the recording surface of the optical disk is not displaced. Therefore, an object of the present invention is to provide an objective lens driving device in which the tilting operation of the objective lens does not cause disturbance to the tracking control system.

[0016]

In order to achieve the above object, a first means comprises an objective lens for condensing a light beam on an optical disk, and an objective lens in a direction of an optical axis or a direction perpendicular to the optical axis. At least one or more drive coils for generating a force for driving the motor, a movable portion including a lens holder for holding the drive coil, and one end fixed to the movable portion to elastically support the movable portion. At least one or more elastic support members, a fixed portion to which the other end of the elastic support member is fixed, at least one or more magnets for generating a driving force on the drive coil, and the movable portion A tilting coil capable of tilting and driving the objective lens in a radial direction of the optical disc; and a magnet for generating a magnetic flux with respect to the tilting coil. Supporting the center position determined by the rigidity balance of the member, it is characterized in that it has set so as substantially to match the principal point of the objective lens.

In order to achieve the above object, a second means includes an objective lens for condensing a light beam on an optical disk, and an objective lens for driving the objective lens in an optical axis direction or a direction perpendicular to the optical axis. A movable part including at least one or more drive coils for generating a force, a lens holder for holding the drive coil, and a plurality of elastic support members having one end fixed to the movable part and elastically supporting the movable part A fixed portion to which the other end of the elastic support member is fixed, at least one or more magnets for generating a driving force in the driving coil, and the objective lens disposed on the movable portion in a radial direction of the optical disc. A tilt coil that can be tiltably driven, and a magnet that generates a magnetic flux with respect to the tilt coil; and the optical disc in the optical axis direction of the objective lens among the plurality of elastic support members. The rigidity of the elastic supporting member click side, is characterized in that it has set the to be greater than the stiffness of the opposite side of the elastic supporting member in the optical axis direction of the optical disc of the objective lens.

In order to achieve the above object, a third means comprises an objective lens for converging a light beam on an optical disk, and an objective lens for driving the objective lens in an optical axis direction or a direction perpendicular to the optical axis. At least one or more drive coils for generating a force, a movable part including a lens holder or the like holding the drive coil, and at least one or more one end fixed to the movable part and elastically supporting the movable part; An elastic support member, a fixed portion to which the other end of the elastic support member is fixed, at least one or more magnets for generating a driving force on the drive coil, and the objective lens disposed on the movable portion. A tilt coil that can be tilted and driven in the radial direction of the optical disc; and a magnet that generates a magnetic flux with respect to the tilt coil, wherein a principal point of the objective lens is separated from the objective lens. Located at a position, and is characterized in that it has set so as substantially to match the support center position determined by the rigidity balance of the center of gravity position or the elastic supporting member of the movable portion.

In order to achieve the above object, a fourth means comprises an objective lens for condensing a light beam on an optical disk, and an objective lens for driving the objective lens in an optical axis direction or a direction perpendicular to the optical axis. At least one or more drive coils for generating a force, a movable part including a lens holder or the like holding the drive coil, and at least one or more one end fixed to the movable part and elastically supporting the movable part; An elastic support member, a fixed portion to which the other end of the elastic support member is fixed, at least one or more magnets for generating a driving force on the drive coil, and the objective lens disposed on the movable portion. A tilt coil that can be tilted and driven in the radial direction of the optical disc; and a magnet that generates a magnetic flux with respect to the tilt coil, wherein the elastic support member includes at least the light of the objective lens. A plurality of elastic support members arranged in the direction, and the elastic support member disposed closest to the optical disk side of the elastic support member, between the elastic support member disposed farthest from the optical disk And at least one of the principal points of the objective lens is arranged.

In order to achieve the above object, a fifth means comprises an objective lens for condensing a light beam on an optical disk, and an objective lens for driving the objective lens in an optical axis direction or a direction perpendicular to the optical axis. At least one or more drive coils for generating a force, a movable part including a lens holder or the like holding the drive coil, and at least one or more one end fixed to the movable part and elastically supporting the movable part; An elastic support member, a fixed portion to which the other end of the elastic support member is fixed, at least one or more magnets for generating a driving force on the drive coil, and the objective lens disposed on the movable portion. A tilt coil that can be tilted and driven in the radial direction of the optical disc; and a magnet that generates a magnetic flux with respect to the tilt coil, wherein at least one of the principal points of the objective lens is the objective lens. And a plurality of the elastic support members are arranged at least in the optical axis direction of the objective lens, and the elastic support member is arranged at a position closest to the optical disk side of the elastic support member. At least one of the principal points of the objective lens is disposed between a supporting member and the elastic supporting member disposed farthest from the optical disk.

In order to achieve the above object, a sixth means comprises an objective lens for condensing a light beam on an optical disk, and an objective lens for driving the objective lens in an optical axis direction or a direction perpendicular to the optical axis. At least one or more drive coils for generating a force, a movable part including a lens holder or the like holding the drive coil, and at least one or more one end fixed to the movable part and elastically supporting the movable part; An elastic support member, a fixed portion to which the other end of the elastic support member is fixed, at least one or more magnets for generating a driving force on the drive coil, and the objective lens disposed on the movable portion. A tilt coil that can be tilted and driven in the radial direction of the optical disc; and a magnet that generates a magnetic flux with respect to the tilt coil. It is characterized in that it has set so as substantially to match the tilt operating center position of the click radially.

In order to achieve the above object, a seventh means comprises an objective lens for condensing a light beam on an optical disk, and an objective lens for driving the objective lens in an optical axis direction or a direction perpendicular to the optical axis. At least one or more drive coils for generating a force, a movable part including a lens holder or the like holding the drive coil, and at least one or more one end fixed to the movable part and elastically supporting the movable part; An elastic support member, a fixed portion to which the other end of the elastic support member is fixed, at least one or more magnets for generating a driving force on the drive coil, and the objective lens disposed on the movable portion. A tilt coil that can be tilted and driven in the radial direction of the optical disc; and a magnet that generates a magnetic flux with respect to the tilt coil, wherein a principal point of the objective lens is separated from the objective lens. Located at a position, and is characterized in that it has set so as substantially to match the tilt operating center position to the optical disk radial direction of the movable portion.

In order to achieve the above object, the eighth means may be any one of the first to seventh means,
A tilt coil is wound around the objective lens substantially at the center,
A first drive coil for driving the objective lens in the optical axis direction is disposed at an outer peripheral portion of the tilting coil in a direction tangential to the optical disk, and at an outer peripheral portion of the first drive coil in the tangential direction of the optical disk. And a second drive coil for driving the objective lens in a radial direction of the optical disc.

In order to achieve the above object, the ninth means may be any one of the first to eighth means,
The tilt driving magnet is arranged on the fixed portion near both sides of an outer peripheral portion of the tilt coil in a radial direction of the optical disk.

In order to achieve the above object, a tenth means comprises an objective lens for condensing a light beam on an optical disk, and an objective lens for driving the objective lens in the optical axis direction or in a direction perpendicular to the optical axis. A movable part including at least one or more magnets for generating a force, a lens holder for holding the magnet, and at least one elastic support having one end fixed to the movable part and elastically supporting the movable part; A member, a fixed part to which the other end of the elastic supporting member is fixed, and a magnetic part generated by the magnet, which is disposed on the fixed part, and acts on the objective lens in the optical axis direction or the optical disk radial direction or both directions. At least one or more drive coils for generating a driving force capable of moving the objective lens, and tilting the objective lens disposed on the fixed portion in a radial direction of the optical disc. And a support center position determined by a gravity center position of the movable portion or a rigidity balance of the elastic support member is set so as to substantially coincide with a principal point position of the objective lens. is there.

In order to achieve the above object, an eleventh means includes an objective lens for condensing a light beam on an optical disk, and an objective lens for driving the objective lens in an optical axis direction or a direction perpendicular to the optical axis. At least one or more magnets for generating a force, a movable part including a lens holder or the like holding the magnet, a plurality of elastic support members having one end fixed to the movable part and elastically supporting the movable part, A fixed portion to which the other end of the elastic support member is fixed, and disposed on the fixed portion, acting on magnetic flux generated from the magnet;
At least one or more drive coils for generating a driving force capable of moving the objective lens in the optical axis direction and / or the radial direction of the optical disk, and tilting the objective lens in the radial direction of the optical disk disposed on the fixed portion. A tilting coil that moves the rigidity of the elastic support member on the optical disk side in the optical axis direction of the objective lens among the plurality of elastic support members, on the opposite side of the optical disk in the optical axis direction of the objective lens. The rigidity of the elastic supporting member is set to be larger than the rigidity of the elastic supporting member.

In order to achieve the above object, a twelfth means comprises an objective lens for condensing a light beam on an optical disk, and an objective lens for driving the objective lens in the optical axis direction or in a direction perpendicular to the optical axis. A movable part including at least one or more magnets for generating a force, a lens holder for holding the magnet, and at least one elastic support having one end fixed to the movable part and elastically supporting the movable part; A member, a fixed part to which the other end of the elastic supporting member is fixed, and a magnetic part generated by the magnet, which is disposed on the fixed part, and acts on the objective lens in the optical axis direction or the optical disk radial direction or both directions. At least one or more drive coils for generating a driving force capable of moving the objective lens, and tilting the objective lens disposed on the fixed portion in a radial direction of the optical disc. A tilting coil that moves, the principal point position of the objective lens is located at a position distant from the objective lens, and substantially at a support center position determined by the center of gravity of the movable portion or the rigidity balance of the elastic support member. It is characterized in that they are set to match.

In order to achieve the above object, a thirteenth means includes an objective lens for condensing a light beam on an optical disk, and an objective lens for driving the objective lens in an optical axis direction or a direction perpendicular to the optical axis. A movable part including at least one or more magnets for generating a force, a lens holder for holding the magnet, and at least one elastic support having one end fixed to the movable part and elastically supporting the movable part; A member, a fixed part to which the other end of the elastic supporting member is fixed, and a magnetic part generated by the magnet, which is disposed on the fixed part, and acts on the objective lens in the optical axis direction or the optical disk radial direction or both directions. At least one or more drive coils for generating a driving force capable of moving the objective lens, and tilting the objective lens disposed on the fixed portion in a radial direction of the optical disc. And a plurality of elastic support members are arranged at least in the optical axis direction of the objective lens, and the elastic support member is arranged at a position of the elastic support member closest to the optical disk side. And at least one of the principal points of the objective lens is arranged between the elastic support member and the elastic support member disposed farthest from the optical disk.

In order to achieve the above object, a fourteenth means comprises an objective lens for condensing a light beam on an optical disk, and an objective lens for driving the objective lens in an optical axis direction or a direction perpendicular to the optical axis. A movable part including at least one or more magnets for generating a force, a lens holder for holding the magnet, and at least one elastic support having one end fixed to the movable part and elastically supporting the movable part; A member, a fixed part to which the other end of the elastic supporting member is fixed, and a magnetic part generated by the magnet, which is disposed on the fixed part, and acts on the objective lens in the optical axis direction or the optical disk radial direction or both directions. At least one or more drive coils for generating a driving force capable of moving the objective lens, and tilting the objective lens disposed on the fixed portion in a radial direction of the optical disc. A tilting coil, at least one of the principal points of the objective lens is arranged at a position distant from the objective lens, and a plurality of the elastic support members are arranged at least in the optical axis direction of the objective lens. ,
And a principal point of the objective lens between the elastic support member disposed closest to the optical disc side of the elastic support member and the elastic support member disposed farthest from the optical disc. Characterized in that at least one of them is arranged.

In order to achieve the above object, a fifteenth means includes an objective lens for condensing a light beam on an optical disk, and an objective lens for driving the objective lens in an optical axis direction or a direction perpendicular to the optical axis. A movable part including at least one or more magnets for generating a force, a lens holder for holding the magnet, and at least one elastic support having one end fixed to the movable part and elastically supporting the movable part; A member, a fixed part to which the other end of the elastic supporting member is fixed, and a magnetic part generated by the magnet, which is disposed on the fixed part, and acts on the objective lens in the optical axis direction or the optical disk radial direction or both directions. At least one or more drive coils for generating a driving force capable of moving the objective lens, and tilting the objective lens disposed on the fixed portion in a radial direction of the optical disc. And a tilt coil, the principal point of the objective lens, is characterized in that set to be substantially coincides with the tilting operation center position to the optical disk radial direction of the movable portion.

In order to achieve the above object, a sixteenth means includes an objective lens for condensing a light beam on an optical disk, and an objective lens for driving the objective lens in an optical axis direction or a direction perpendicular to the optical axis. A movable part including at least one or more magnets for generating a force, a lens holder for holding the magnet, and at least one elastic support having one end fixed to the movable part and elastically supporting the movable part; A member, a fixed part to which the other end of the elastic supporting member is fixed, and a magnetic part generated by the magnet, which is disposed on the fixed part, and acts on the objective lens in the optical axis direction or the optical disk radial direction or both directions. At least one or more drive coils for generating a driving force capable of moving the objective lens, and tilting the objective lens disposed on the fixed portion in a radial direction of the optical disc. A tilting coil that sets the principal point of the objective lens at a position distant from the objective lens and substantially coincides with the center of the tilting operation of the movable portion in the radial direction of the optical disc. It is characterized by having done.

In order to achieve the above object, the seventeenth means may be any one of the tenth to sixteenth means, wherein one magnet is provided on each of four surfaces of the lens holder having a substantially square cross section. It is characterized by being arranged.

In order to achieve the above object, the eighteenth means may be any one of the tenth to seventeenth means, wherein the driving coil and the tilting coil drive the objective lens in the optical axis direction. And at least one set of the same coils, and the coils are arranged on the fixed portion near both sides of the outer periphery of the movable portion in the radial direction of the optical disk.

In order to achieve the above object, the nineteenth means may be any one of the tenth to seventeenth means, wherein the driving coil and the tilting coil for driving the objective lens in the optical axis direction thereof. Are constituted by at least one set of the same coils, and the coils are arranged on the fixed portion near both sides of the outer peripheral portion of the movable portion in the tangential direction of the optical disk.

In order to achieve the above object, the twentieth means according to any one of the tenth to seventeenth means, wherein the drive coil for driving the objective lens in the optical axis direction and the objective lens are provided. The drive coil for driving in the radial direction of the optical disk and the movable portion are disposed on the fixed portion near both sides of the outer peripheral portion of the movable portion in the tangential direction of the optical disk, and the tilting coil is disposed near both sides of the outer peripheral portion of the movable portion in the radial direction of the optical disk. It is characterized by being arranged on the fixed part.

[0036]

Embodiments of the present invention will be described below with reference to the drawings. 1 and 2 are a front sectional view and a top view of an objective lens driving device according to a first embodiment of the present invention.

In these figures, the objective lens 1 is disposed on the upper surface of the lens holder 2. A tilting coil 5 is wound around the center of the lens holder 2 with the objective lens 1 substantially at the center of its winding. On both sides of the tilting coil 5 in the tangential direction of the optical disk, the focusing coil 3 as an air-core coil is arranged so as to be sandwiched between the arm portions of the lens holder 2. A tracking coil 4 is arranged outside the focusing coil 3 in the tangential direction of the optical disk so as to be hooked on the lens holder 2.

A movable section is composed of the objective lens 1, lens holder 2, focusing coil 3, tracking coil 4, tilting coil 5, and the like. The movable portion is supported by four elastic support members 8, and one end of the elastic support member 8 is fixed to the movable portion, and the other end is fixed to the fixed portion.

The elastic support member 8 is made of a conductive material, and is electrically connected to the focusing coil 3 and the tracking coil 4 disposed on a movable portion, respectively. 8, a current can be supplied to the focusing coil 3 and the tracking coil 4.

The tilting coil 5 is electrically connected to the fixed part via a lead wire (not shown), and supplies a current from the fixed part, like the focusing coil 3 and the tracking coil 4. It is possible.

The position G of the center of gravity of the movable part in the optical axis direction of the objective lens 1 substantially coincides with the center position of the focusing coil 3 and the tracking coil 4 in the optical axis direction of the objective lens 1. The weight and arrangement position of each part are determined. In addition, the four elastic support members 8
Also, the support center position P determined by the rigidity balance of the moving part is configured to substantially match the center positions of the focusing coil 3 and the tracking coil 4, and as a result, the center of gravity G of the movable part and the support center position P They almost match.

The principal point position S, which is the optical center of the objective lens 1, substantially coincides with the center of gravity position G of the entire movable part and the support center position P determined by the rigidity balance of the four elastic support members 8. Designed for Therefore, even if the movable part tilts around its center of gravity position G or the support center position P, the principal point position S of the objective lens 1 does not displace in the tracking direction. The position of the light spot on the recording surface of the optical disk thus recorded is not displaced in the tracking direction.

A yoke 7 and magnets 6 (6a, 6b) are fixed to a fixed portion to which one end of the elastic support member 8 is fixed.
Are arranged. There are two sets of the magnetic circuits, each of which includes the focusing coil 3 and the tracking coil 4 in its magnetic gap.
Are arranged such that the effective line portion of the

Further, two magnets 6 for tilting drive are provided.
The magnets 6c and 6d are arranged outside the movable part, and the magnetic flux emitted from the magnets 6c and 6d and the current flowing through the tilting coil 5 generate a tilt driving force.

Although not shown, the optical disk and the objective lens 1
Is detected by calculating the amount of jitter from the signal read from the optical disk. A tilt drive circuit for generating a tilt drive signal is arranged so as to reduce the jitter amount, and an appropriate drive current is supplied to the tilt coil 5 by a signal from the tilt drive circuit. It has become.

Next, in the first embodiment of the present invention,
The operation will be described. The optical pickup optically generates a focusing error signal for the vertical run-out of the optical disk, and supplies an appropriate drive current to the focusing coil 3 from the focusing drive circuit in accordance with this signal. Focusing control is performed so that the light spot of the emitted light beam is always positioned on the recording surface of the optical disk.

In addition, for meandering and eccentricity of the truck,
In the optical pickup, a tracking error signal is generated optically, an appropriate drive current is supplied from the tracking drive circuit to the tracking coil 4 in accordance with the signal, and the light spot of the light beam condensed by the objective lens 1 is constantly generated. Tracking control is performed so as to be located on a track of the optical disc. In this way, the focusing control and the tracking control are executed, and it becomes possible to read a signal from the optical disc.

On the other hand, the signal read from the optical disc contains an error (jitter) in the time axis direction whose magnitude is mainly affected by the relative tilt angle between the optical disc and the objective lens 1. Therefore, by appropriately tilting the objective lens 1 in accordance with the tilt of the optical disk, it is possible to suppress the jitter amount. vice versa,
The amount of jitter included in the read signal is calculated, a tilt drive signal for the objective lens 1 is created so that the jitter amount is minimized, and the tilt coil 5 is driven in accordance with the tilt drive signal.
The tilt control of the objective lens 1 (tilt control) can be performed by supplying an appropriate tilt drive current to the objective lens 1.

At this time, the entire movable portion performs a tilting operation around the center of gravity position G of the movable portion or the support center position P determined by the rigidity balance of the four elastic support members 8 by the tilt driving force. Therefore, the end surface of the objective lens 1 disposed at a position away from the center of gravity G of the movable portion or the support center position P toward the optical disk moves in the tracking direction simultaneously with the tilting operation in the radial direction of the optical disk.

However, in the objective lens driving device according to the present embodiment, the principal point position S, which is the optical center position of the objective lens 1, substantially coincides with the center of gravity G or the support center position P of the movable part. Although the end surface of the objective lens 1 moves in the tracking direction, the principal point position S of the objective lens 1 hardly displaces in the tracking direction.

Accordingly, the position of the light spot on the recording surface of the optical disk focused by the objective lens 1 hardly moves. As a result, even if the objective lens 1 is tilted in the radial direction of the optical disk in a state where the focusing control and the tracking control are performed, the light spot position on the optical disk recording surface does not move due to the tilting operation. As a result, it is possible to read or write a normal signal with small jitter from the optical disk.

FIGS. 3, 4 and 5 show the second embodiment of the present invention, respectively.
FIG. 3 is a front sectional view, a top view, and a transverse sectional view in the radial direction of the optical disc of the objective lens driving device according to the embodiment. In these figures, the objective lens 1 is disposed on the upper surface of the lens holder 2. Further, a focusing coil 3, a tracking coil 4, a tilting coil 5, and the like are arranged on the lens holder 2 to constitute a movable portion. The movable portion is supported by four elastic support members 8, and one end of the elastic support member 8 is fixed to the movable portion, and the other end is fixed to the fixed portion.

The elastic support member 8 is made of a conductive material, and is electrically connected to the focusing coil 3 and the tracking coil 4 disposed on a movable portion, respectively. A current can be supplied to the focusing coil 3 and the tracking coil 4 via the elastic support member 8.

The tilting coil 5 is electrically connected to the fixed part via a lead wire (not shown), and supplies a current from the fixed part like the focusing coil 3 and the tracking coil 4. It is possible.

In this embodiment, of the four elastic support members 8 elastically supporting the movable portion, the rigidity of the elastic support members 8a and 8b elastically supporting the upper side of the movable portion, that is, the optical disk side or the objective lens 1 side. Are configured to be sufficiently larger than the rigidity of the elastic support members 8c and 8d for elastically supporting the lower side of the movable portion, that is, the opposite side of the optical disk.

Accordingly, when the objective lens 1 is tilted and driven in the radial direction of the optical disk, the movable portion disposed on the upper surface thereof is driven by the elastic support member 8a supporting the movable portion having sufficiently large rigidity. , 8b support center position P
Is tilted around the tilt center.

The principal point position S which is the optical center position of the objective lens 1 is determined by the support center position P of the elastic support members 8a and 8b which support the upper side of the movable portion among the elastic support members 8 which elastically support the movable portion. The mounting position of the objective lens 1 or the elastic support member 8 is designed so as to correspond to.

Therefore, even if the movable portion on which the objective lens 1 is disposed is tilted with the support center position P of the upper elastic support members 8a and 8b elastically supporting the movable portion as the tilt center, the tilt center is maintained. And the principal point position S, which is the optical center of the objective lens 1, substantially coincides with each other.
The position of the light spot on the recording surface of the optical disk focused by the optical disk is not displaced in the tracking direction.

That is, similarly to the first embodiment, the center of the tilting operation of the objective lens 1 and the principal point position S of the objective lens 1 substantially coincide with each other, and the tilting operation of the objective lens 1 in the radial direction of the optical disk is performed. In addition, the principal point position S of the objective lens 1 is not displaced in the tracking direction. Therefore, the same effects as those of the first embodiment can be obtained in the second embodiment.

FIGS. 6, 7, and 8 are a front sectional view, a top view, and a transverse sectional view in the radial direction of the optical disk, respectively, of an objective lens driving device according to a third embodiment of the present invention. In these drawings, the objective lens 1 is disposed on the upper surface of the lens holder 2. Further, a focusing coil 3, a tracking coil 4,
The tilt coil 5 and the like are arranged to form a movable part. The movable portion is supported by four elastic support members 8, and one end of the elastic support member 8 is fixed to the movable portion, and the other end is fixed to the fixed portion.

The elastic support member 8 is made of a conductive material, and is electrically connected to the focusing coil 3 and the tracking coil 4 disposed on a movable portion, respectively. Support member 8
, A current can be applied to the focusing coil 3 and the tracking coil 4.

The tilting coil 5 is electrically connected to the fixed part via a lead wire (not shown), and supplies a current from the fixed part like the focusing coil 3 and the tracking coil 4. It is possible.

In this embodiment, the objective lens 1 is designed such that the principal point position S, which is the optical center of the objective lens 1, is apart from the objective lens 1 itself. The principal point position S of the objective lens 1 set apart from the objective lens 1 is determined by the position of the center of gravity G of the movable portion of the objective lens driving device or the rigidity balance of the elastic support member 8 that elastically supports the movable portion. Is designed to substantially coincide with the support center position P determined by

Therefore, even if the objective lens 1 is tilted with the support center position P determined by the rigidity balance of the elastic supporting member 8 elastically supporting the movable portion as the tilting center, or the movable portion on which the objective lens 1 is disposed, Even when the objective lens 1 is tilted with the center of gravity position G as the tilt center, the light is condensed by the objective lens 1 because the tilt center and the principal point position S, which is the optical center of the objective lens 1, substantially coincide with each other. The position of the light spot on the recording surface of the optical disk is not displaced in the tracking direction.

That is, similarly to the first embodiment, the center of the tilting operation of the objective lens 1 and the principal point position S of the objective lens 1 substantially coincide with each other, and the tilting operation of the objective lens 1 in the radial direction of the optical disc causes In addition, the principal point position S of the objective lens 1 is not displaced in the tracking direction. Therefore, in the third embodiment, the same effect as in the first embodiment can be obtained.

FIGS. 9, 10, and 11 are a front sectional view, a top view, and a transverse sectional view in the radial direction of an optical disk, respectively, of an objective lens driving device according to a fourth embodiment of the present invention. In these drawings, the objective lens 1 is disposed on the upper surface of the lens holder 2. Further, magnets 6 are arranged on the four side surfaces of the lens holder 2, respectively, and constitute movable parts. The movable portion is supported by four elastic support members 8, and one end of the elastic support member 8 is fixed to the movable portion, and the other end is fixed to the fixed portion.

In the fixed portion, a focusing coil 3 and a tracking coil 4 are arranged on both sides of the movable portion in the tangential direction of the optical disk, so that the objective lens 1 can operate in the focusing direction and the tracking direction.

The tilting coil 5 is disposed at a position rotated by 90 ° with respect to the focusing coil 3 and the tracking coil 4, and is used to determine the relationship between the current flowing through the tilting coil 5 and the magnetic flux emitted from the magnets 6 c and 6 d disposed in the movable part. The tilt driving force is generated by the action.

In this embodiment, the function of the focusing coil 3 can be provided to the tilting coil 5 by eliminating the focusing coil 3 shown in FIG. Even in that case, the same effect can be obtained, so that the configuration of the focusing coil 3 and the tilting coil 5 has a degree of freedom.

In this embodiment, the objective lens 1 is designed such that the principal point position S, which is the optical center of the objective lens 1, is apart from the objective lens 1 itself. The principal point position S of the objective lens 1 set apart from the objective lens 1 is determined by the position of the center of gravity G of the movable portion of the objective lens driving device or the rigidity of the elastic support member 8 that elastically supports the movable portion. It is designed to substantially coincide with the support center position P determined by the balance.

Therefore, even if the objective lens 1 is tilted with the support center position P determined by the rigidity balance of the elastic supporting member 8 elastically supporting the movable portion as the tilting center, or the movable portion on which the objective lens 1 is disposed, Even if the objective lens 1 is tilted with the center of gravity position G as the tilt center, the tilting operation center and the principal point position S which is the optical center of the objective lens 1 substantially coincide with each other. The position of the light spot on the recording surface of the optical disk is not displaced in the tracking direction.

That is, as in the first embodiment, the center of the tilting operation of the objective lens 1 and the principal point position S of the objective lens 1 substantially coincide with each other, and the tilting operation of the objective lens 1 in the radial direction of the optical disk is performed. In addition, the principal point position S of the objective lens 1 is not displaced in the tracking direction. Therefore, also in the fourth embodiment, the same effect as in the first embodiment can be obtained.

FIGS. 12 and 13 are a front sectional view and a transverse sectional view in the radial direction of an optical disk according to a fifth embodiment of the present invention, respectively. In these figures, the objective lens 1
Are arranged on the upper surface of the lens holder 2. Further, a focusing coil 3, a tracking coil 4, a tilting coil 5, and the like are arranged on a side surface of the lens holder 2, and constitute a movable portion. The movable portion is supported by four elastic support members 8, and one end of the elastic support member 8 is connected to the movable portion.
The other end is fixed to a fixing part.

A magnetic circuit comprising a magnet 6 and a yoke 7 for generating a magnetic flux acting on each of the coils is disposed in the fixed portion, and the objective lens 1 is operable in the focusing direction and the tracking direction. The optical disc is configured to be capable of tilting in the radial direction of the optical disc.

In this embodiment, the principal point position S which is the optical center of the objective lens 1 is located within the objective lens 1 itself, but the elastic support members 8a, 8 closest to the optical disk are located.
b and the elastic support members 8c and 8 farthest from the optical disk
d.

The principal point position S of the objective lens 1 is
Although it does not substantially coincide with the center of gravity G of the movable part of the objective lens driving device or the support center position P determined by the rigidity balance of the elastic support member 8 that elastically supports the movable part, it is designed to be located as close as possible. ing.

Therefore, even if the objective lens 1 tilts with the support center position P determined by the rigidity balance of the elastic supporting member 8 elastically supporting the movable portion as the tilt center, or the movable portion on which the objective lens 1 is disposed Even if the objective lens 1 tilts with the center of gravity position G as the tilt center, the distance between the tilting operation center and the principal point position S which is the optical center of the objective lens 1 is short, so that the optical disc condensed by the objective lens 1 The displacement amount in the tracking direction due to the tilting operation of the light spot position on the recording surface can be kept very small.

That is, although not as complete as in the first embodiment, the amount of displacement of the light spot in the tracking direction due to the tilting operation of the objective lens 1 can be suppressed to a practically acceptable level. Therefore, also in the fifth embodiment, it is possible to obtain the same effects as those of the first embodiment at a practical level.

Further, in this embodiment, the principal point position S, which is the optical center of the objective lens 1, is disposed within the objective lens 1 itself, but the principal point position S is located at a position away from the object lens 1 itself. It goes without saying that the same effect can be obtained even if they are arranged.

[0080]

As described above, according to the present invention, since the center position of the tilting operation of the movable portion on which the objective lens is disposed substantially coincides with the principal point position which is the optical center of the objective lens, In order to optimize the relative tilt angle between the objective lens and the objective lens, the principal point of the objective lens may move in the tracking direction even if the movable part on which the objective lens is arranged is tilted in the radial direction of the optical disc. Almost no.

Therefore, the position of the light spot on the recording surface of the optical disk hardly moves in the tracking direction due to the tilting operation of the objective lens in the radial direction of the optical disk.
As a result, no disturbance to the tracking control system is generated.

As a result, the objective lens can be tilted in the radial direction of the optical disk while performing the focusing control and the tracking control, and the tilt can be controlled to the optimum tilt. As a result, an accurate signal reading with small jitter can be performed on the optical disk. And writing can be performed.

[Brief description of the drawings]

FIG. 1 is a front sectional view of a first embodiment of an objective lens driving device according to the present invention.

FIG. 2 is a top view of the first embodiment of the objective lens driving device according to the present invention.

FIG. 3 is a front sectional view of a second embodiment of the objective lens driving device according to the present invention.

FIG. 4 is a top view of a second embodiment of the objective lens driving device according to the present invention.

FIG. 5 is a radial cross-sectional view of an objective lens driving device according to a second embodiment of the present invention in a radial direction of an optical disc.

FIG. 6 is a front sectional view of a third embodiment of the objective lens driving device according to the present invention.

FIG. 7 is a top view of a third embodiment of the objective lens driving device according to the present invention.

FIG. 8 is a cross-sectional view of an objective lens driving device according to a third embodiment of the present invention in a radial direction of an optical disc.

FIG. 9 is a front sectional view of a fourth embodiment of the objective lens driving device according to the present invention.

FIG. 10 is a top view of a fourth embodiment of the objective lens driving device according to the present invention.

FIG. 11 is a cross-sectional view in a radial direction of an optical disk of an objective lens driving device according to a fourth embodiment of the present invention.

FIG. 12 is a front sectional view of a fifth embodiment of the objective lens driving device according to the present invention.

FIG. 13 is a cross-sectional view of an objective lens driving device according to a fifth embodiment of the present invention in a radial direction of an optical disc.

FIG. 14 is a front sectional view of a conventional objective lens driving device.

FIG. 15 is a top view of a conventional objective lens driving device.

FIG. 16 is a transverse cross-sectional view of a conventional objective lens driving device in the radial direction of an optical disk.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Objective lens 2 Lens holder 3 Focusing coil 4 Tracking coil 5 Tilt coil 6 Magnet 7 Yoke 8 Elastic support member 9 Tilt detector

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Michio Miura 1 Kitano, Makino, Mizusawa-shi, Iwate F-term in Hitachi Media Electronics Co., Ltd. 5D118 AA13 BA01 BB02 BF02 BF03 CC12 CD02 CD03 CD04 CD08 DC03 EA02 EB01 EB15 EC04 ED08 EE04 EE05 EE06 EF09 FA29 FB03 FB10 FB20

Claims (20)

[Claims] 1. An objective lens for condensing a light beam on an optical disk, at least one or more drive coils for generating a force for driving the objective lens in an optical axis direction or a direction perpendicular to the optical axis, A movable portion including a lens holder or the like that holds the drive coil, at least one elastic support member having one end fixed to the movable portion and elastically supporting the movable portion, and the other end of the elastic support member A fixed portion to be fixed, at least one or more magnets for generating a driving force in the drive coil, a tilt coil capable of tilting and driving the objective lens arranged in the movable portion in a radial direction of the optical disc; A magnet that generates a magnetic flux with respect to the tilt coil, wherein the center of gravity of the movable portion or the support center position determined by the rigidity balance of the elastic support member is An objective lens driving apparatus is characterized in that set to be substantially coincides with the principal point of the object lens. 2. An objective lens for condensing a light beam on an optical disk, at least one or more drive coils for generating a force for driving the objective lens in an optical axis direction or a direction perpendicular to the optical axis. A movable portion including a lens holder or the like holding the drive coil, a plurality of elastic support members having one end fixed to the movable portion and elastically supporting the movable portion, and the other end of the elastic support member fixed; A fixed portion, at least one or more magnets for generating a driving force in the drive coil, a tilt coil capable of tilting and driving the objective lens disposed in the movable portion in a radial direction of the optical disc, and a tilt coil. A magnet that generates a magnetic flux with respect to the elastic support member, wherein the rigidity of the elastic support member on the optical disk side in the optical axis direction of the objective lens is set to the object. An objective lens driving apparatus is characterized in that set to be greater than the stiffness of the opposite side of the elastic support members lens in the optical axis direction of the optical disc. 3. An objective lens for condensing a light beam on an optical disk, at least one or more drive coils for generating a force for driving the objective lens in the optical axis direction or in a direction perpendicular to the optical axis, A movable portion including a lens holder or the like that holds the drive coil, at least one elastic support member having one end fixed to the movable portion and elastically supporting the movable portion, and the other end of the elastic support member A fixed portion to be fixed, at least one or more magnets for generating a driving force in the drive coil, a tilt coil capable of tilting and driving the objective lens arranged in the movable portion in a radial direction of the optical disc; A magnet that generates a magnetic flux with respect to the tilting coil, wherein a principal point of the objective lens is located at a position distant from the objective lens, and a center of gravity of the movable part is provided. Rui objective lens driving device is characterized in that set to be substantially coincident to a support center position determined by the rigidity balance of the elastic support member. 4. An objective lens for condensing a light beam on an optical disk, and at least one or more drive coils for generating a force for driving the objective lens in an optical axis direction or a direction perpendicular to the optical axis, A movable portion including a lens holder or the like that holds the drive coil, at least one elastic support member having one end fixed to the movable portion and elastically supporting the movable portion, and the other end of the elastic support member A fixed portion to be fixed, at least one or more magnets for generating a driving force in the drive coil, a tilt coil capable of tilting and driving the objective lens arranged in the movable portion in a radial direction of the optical disc; A magnet that generates a magnetic flux with respect to the tilting coil, wherein a plurality of the elastic support members are arranged at least in the optical axis direction of the objective lens; At least one of the principal points of the objective lens is provided between the elastic support member disposed closest to the optical disc side of the material and the elastic support member disposed farthest from the optical disc. An objective lens driving device, which is disposed. 5. An objective lens for condensing a light beam on an optical disk, at least one or more drive coils for generating a force for driving the objective lens in an optical axis direction or a direction perpendicular to the optical axis, A movable portion including a lens holder or the like that holds the drive coil, at least one elastic support member having one end fixed to the movable portion and elastically supporting the movable portion, and the other end of the elastic support member A fixed portion to be fixed, at least one or more magnets for generating a driving force in the drive coil, a tilt coil capable of tilting and driving the objective lens arranged in the movable portion in a radial direction of the optical disc; A magnet for generating a magnetic flux with respect to the tilt coil, at least one of the principal points of the objective lens is disposed at a position away from the objective lens, and A plurality of holding members are arranged at least in the optical axis direction of the objective lens, and the elastic support member arranged at a position closest to the optical disk side of the elastic support member, and at a position farthest from the optical disk. An objective lens driving device, wherein at least one of the principal points of the objective lens is arranged between the elastic support member and the elastic support member. 6. An objective lens for condensing a light beam on an optical disk, at least one or more drive coils for generating a force for driving the objective lens in an optical axis direction or a direction perpendicular to the optical axis, A movable portion including a lens holder or the like that holds the drive coil, at least one elastic support member having one end fixed to the movable portion and elastically supporting the movable portion, and the other end of the elastic support member A fixed portion to be fixed, at least one or more magnets for generating a driving force in the drive coil, a tilt coil capable of tilting and driving the objective lens arranged in the movable portion in a radial direction of the optical disc; A magnet for generating a magnetic flux with respect to the tilting coil, wherein a principal point position of the objective lens substantially coincides with a tilting center position of the movable portion in the radial direction of the optical disc. An objective lens driving device, characterized in that the set as. 7. An objective lens for condensing a light beam on an optical disk, at least one or more drive coils for generating a force for driving the objective lens in an optical axis direction or a direction perpendicular to the optical axis, A movable portion including a lens holder or the like that holds the drive coil, at least one elastic support member having one end fixed to the movable portion and elastically supporting the movable portion, and the other end of the elastic support member A fixed portion to be fixed, at least one or more magnets for generating a driving force in the drive coil, a tilt coil capable of tilting and driving the objective lens arranged in the movable portion in a radial direction of the optical disc; A magnet for generating a magnetic flux with respect to the tilting coil, wherein the principal point of the objective lens is located at a position distant from the objective lens, and An objective lens driving apparatus is characterized in that set to be substantially coincides with the tilting operation center position of the disk radial direction. 8. The tilting coil according to claim 1, wherein the tilting coil is wound around the objective lens substantially at a center thereof, and the objective lens is mounted on an outer peripheral portion of the tilting coil in a tangential direction of the optical disk. A first drive coil for driving in the axial direction is disposed, and a second drive coil for driving the objective lens in a radial direction of the optical disc is disposed on an outer peripheral portion of the first drive coil in a tangential direction of the optical disc. An objective lens driving device, characterized in that: 9. The tilt motor according to claim 1, wherein the tilt driving magnet is disposed on the fixed portion near both sides of an outer peripheral portion of the tilt coil in a radial direction of the optical disk. Objective lens driving device. 10. An objective lens for converging a light beam on an optical disk, at least one or more magnets for generating a force for driving the objective lens in an optical axis direction or a direction perpendicular to the optical axis; A movable portion including a lens holder for holding a magnet, at least one or more elastic support members having one end fixed to the movable portion and elastically supporting the movable portion, and the other end of the elastic support member fixed; And at least one of a fixed portion disposed on the fixed portion and acting on magnetic flux generated from the magnet to generate a driving force for moving the objective lens in the optical axis direction or the optical disk radial direction or both directions. A driving coil, and a tilt coil disposed on the fixed portion for tilting and driving the objective lens in a radial direction of the optical disc; and a center of gravity of the movable portion. Supporting the center position determined by the rigidity balance of location or the elastic support member, an objective lens driving device is characterized in that set so as to coincide with the principal point of substantially the objective lens. 11. An objective lens for converging a light beam on an optical disk, at least one or more magnets for generating a force for driving the objective lens in an optical axis direction or a direction perpendicular to the optical axis. A movable portion including a lens holder for holding a magnet, a plurality of elastic support members having one end fixed to the movable portion and elastically supporting the movable portion, and a fixed portion to which the other end of the elastic support member is fixed And at least one drive that is disposed on the fixed portion and acts on magnetic flux generated from the magnet to generate a driving force that enables the objective lens to move in the optical axis direction, the optical disk radial direction, or both directions. A coil, and a tilt coil that is disposed on the fixed portion and that tilts and drives the objective lens in a radial direction of the optical disc, among the plurality of elastic support members, The rigidity of the elastic support member on the optical disc side in the optical axis direction of the objective lens is set to be greater than the rigidity of the elastic support member on the opposite side of the optical disc in the optical axis direction of the objective lens. Characteristic objective lens driving device. 12. An objective lens for converging a light beam on an optical disk, at least one or more magnets for generating a force for driving the objective lens in an optical axis direction or a direction perpendicular to the optical axis. A movable portion including a lens holder for holding a magnet, at least one or more elastic support members having one end fixed to the movable portion and elastically supporting the movable portion, and the other end of the elastic support member fixed; And at least one of a fixed portion disposed on the fixed portion and acting on magnetic flux generated from the magnet to generate a driving force for moving the objective lens in the optical axis direction or the optical disk radial direction or both directions. The above-described drive coil, and a tilt coil that is disposed on the fixed portion and that tilts and drives the objective lens in a radial direction of the optical disc; The object is characterized in that the point position is located at a position distant from the objective lens and substantially coincides with the center of gravity of the movable part or the support center position determined by the rigidity balance of the elastic support member. Lens drive. 13. An objective lens for condensing a light beam on an optical disk, at least one or more magnets for generating a force for driving the objective lens in an optical axis direction or a direction perpendicular to the optical axis. A movable portion including a lens holder for holding a magnet, at least one or more elastic support members having one end fixed to the movable portion and elastically supporting the movable portion, and the other end of the elastic support member fixed; And at least one of a fixed portion disposed on the fixed portion and acting on magnetic flux generated from the magnet to generate a driving force for moving the objective lens in the optical axis direction or the optical disk radial direction or both directions. The above-mentioned elastic supporting member, comprising: the above-mentioned driving coil; At least a plurality of the objective lenses are arranged in the optical axis direction, and the elastic support member is arranged at a position closest to the optical disc side of the elastic support member, and is arranged at a position farthest from the optical disc. An objective lens driving device, wherein at least one of the principal points of the objective lens is disposed between the elastic lens and the elastic support member. 14. An objective lens for condensing a light beam on an optical disk, at least one or more magnets for generating a force for driving the objective lens in an optical axis direction or a direction perpendicular to the optical axis. A movable portion including a lens holder for holding a magnet, at least one or more elastic support members having one end fixed to the movable portion and elastically supporting the movable portion, and the other end of the elastic support member fixed; And at least one of a fixed portion disposed on the fixed portion and acting on magnetic flux generated from the magnet to generate a driving force for moving the objective lens in the optical axis direction or the optical disk radial direction or both directions. The above-described drive coil, and a tilt coil that is disposed on the fixed portion and that tilts and drives the objective lens in a radial direction of the optical disc; At least one of the points is arranged at a position distant from the objective lens, and a plurality of the elastic support members are arranged at least in the optical axis direction of the objective lens, and the elastic support member is closest to the optical disk. Wherein at least one of the principal points of the objective lens is arranged between the elastic support member arranged at a position close to the optical disc and the elastic support member arranged at a position farthest from the optical disc. Objective lens driving device. 15. An objective lens for condensing a light beam on an optical disc, at least one or more magnets for generating a force for driving the objective lens in an optical axis direction or a direction perpendicular to the optical axis. A movable portion including a lens holder for holding a magnet, at least one or more elastic support members having one end fixed to the movable portion and elastically supporting the movable portion, and the other end of the elastic support member fixed; And at least one of a fixed portion disposed on the fixed portion and acting on magnetic flux generated from the magnet to generate a driving force for moving the objective lens in the optical axis direction or the optical disk radial direction or both directions. The above-described drive coil, and a tilt coil that is disposed on the fixed portion and that tilts and drives the objective lens in a radial direction of the optical disc; Point position, the objective lens driving device is characterized in that set to be substantially coincides with the tilting operation center position to the optical disk radial direction of the movable portion. 16. An objective lens for converging a light beam on an optical disk, at least one or more magnets for generating a force for driving the objective lens in an optical axis direction or a direction perpendicular to the optical axis. A movable portion including a lens holder for holding a magnet, at least one or more elastic support members having one end fixed to the movable portion and elastically supporting the movable portion, and the other end of the elastic support member fixed; And at least one of a fixed portion disposed on the fixed portion and acting on magnetic flux generated from the magnet to generate a driving force for moving the objective lens in the optical axis direction or the optical disk radial direction or both directions. The above-described drive coil, and a tilt coil that is disposed on the fixed portion and that tilts and drives the objective lens in a radial direction of the optical disc; Point position, the present in a position away from the objective lens, and an objective lens driving device is characterized in that set to be substantially coincides with the tilting operation center position to the optical disk radial direction of the movable portion. 17. The objective lens driving device according to claim 10, wherein one magnet is arranged on each of four surfaces of a lens holder having a substantially square cross section. 18. The apparatus according to claim 10, wherein the drive coil for driving the objective lens in the optical axis direction and the tilt coil are at least one.
An objective lens driving device comprising: at least one set of the same coils; and wherein the coils are arranged on the fixed portion near both sides of an outer peripheral portion of the movable portion in a radial direction of the optical disk. 19. The apparatus according to claim 10, wherein the drive coil for driving the objective lens in the optical axis direction and the tilt coil are at least one.
An objective lens driving device comprising: at least one set of the same coils; and wherein the coils are disposed on the fixed portion near both sides of an outer peripheral portion of the movable portion in a direction tangential to the optical disk. 20. The movable part according to claim 10, wherein the drive coil for driving the objective lens in the optical axis direction and the drive coil for driving the objective lens in a radial direction of the optical disk are connected to the movable part. Wherein the tilting coil is disposed on the fixed portion near both sides of an outer peripheral portion of the movable portion in the radial direction of the optical disk. apparatus.