JPH09320060A - Optical pick-up device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To protect an actuator and to reduce its height, in an optical pick-up device with an objective lens being supported by the actuator. SOLUTION: An objective lens housing part 3 where a two-axis actuator 12 that supports an objective lens 11 at a slide base 2 is mounted is formed in a recessed enclosure shape, and a peripheral wall part 7 with a height where a lens holder 13 of the two-axis actuator 12 and a support 20 do not protrude is formed in protrusion in one piece at the peripheral edge part in a frame. As a result, the two-axis actuator 12 is protected against the traveling direction of the slide base 2 and an area on a movable part needs not be covered with a cover, thus reducing the height of the device body.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical pickup device provided in an optical disk reproducing device, a magneto-optical disk recording / reproducing device and the like.

[0002]

2. Description of the Related Art Conventionally, an optical pickup device is provided alone in an optical disk reproducing device, and in a recording / reproducing device for a recordable / reproducible magneto-optical disk, an optical pickup device is combined with a magnetic head device as an overwrite head. It is provided as a magnetic head mechanism.

The optical magnetic head mechanism provided in the magneto-optical disk recording / reproducing apparatus is constructed as shown in FIG.

The optical magnetic head mechanism 60 includes an optical pickup device 62 having an objective lens 61 for irradiating the signal recording surface of the magneto-optical disk with laser light, and a predetermined external magnetic field for the signal recording surface of the magneto-optical disk. A magnetic head device 64 provided with a magnetic field applying head 63 for applying a magnetic field is applied to a bracket 65 formed in a substantially U-shape in a side view so as to face each other across the magneto-optical disk D in the vertical direction. .

The optical magnetic head mechanism 60 is a slide base 6 which is the main body of the optical pickup device 62.
6, a guide shaft hole 67a provided on one end side and a guide groove 67b provided on the other end side, which is substantially U-shaped in side view, are laterally fixed to the chassis (not shown) side.
The turntable 70 is fitted and engaged with a and 68b so as to be movable in the contact and separation directions with respect to the turntable 70. Further, a screw receiver 71 is attached to the bracket 65 and is screwed to a rotary screw shaft 74 of a stepping motor 73 supported by a motor bracket 72 on the chassis (not shown) side. The rotation of the rotary screw shaft 74 causes the optical magnetic head mechanism 60 to move toward and away from the turntable 70, that is, to move in the radial direction of the magneto-optical disk D chucked on the turntable 70. Magneto-optical disk D
Recording / playback is performed on the. In FIG. 8, 69
Is an actuator cover attached to the slide base 66.

Further, in the optical disk reproducing apparatus, since the optical pickup apparatus is independently provided, the screw base is directly attached to the slide base, and the rotary screw shaft of the stepping motor is screwed into the optical disk reproducing apparatus, so The pickup device is configured to be moved in the radial direction with respect to the optical disk chucked on the turntable for reproduction.

[0007]

SUMMARY OF THE INVENTION With this configuration,
An optical pickup device that operates includes an objective lens supported by an actuator on one half side of a slide base, and an optical system member for the objective lens is accommodated on the other half side of the slide base. Since it is attached to the slide base in a state of protruding to the upper surface side, from the upper surface side with only the objective lens exposed to prevent contact with other members, catching, etc. during operation etc. The actuator is protected by being covered with an actuator cover over the peripheral side surface.

However, this actuator cover is
Since the movable part of the actuator is mounted on the slide base with a certain space between the upper part and the movable part of the actuator so that it does not hit even when it moves upward, Since the height of the pickup device main body is increased, a large moving space is required, and the optical disc reproducing device and the magneto-optical disc recording / reproducing device including the optical pickup device are limited in size and thickness.

Further, the actuator cover is large in size because it covers the entire upper surface of the actuator, which is disadvantageous in terms of cost.

The present invention has been made in view of the above points, and an object thereof is to provide an optical pickup device in which an actuator supporting an objective lens is directly protected on the side of a slide base that houses the actuator. And

[0011]

In order to achieve the above object, an optical pickup device according to the present invention is provided with a recess for accommodating an actuator supporting the objective lens in a slide base for accommodating the objective lens, and a peripheral edge of the recess. A protective peripheral wall portion for protecting the actuator is formed in a predetermined range in the portion.

As described above, by forming the slide base for accommodating the objective lens, the actuator supporting the objective lens is directly protected on the side of the slide base, and the movable portion is protected by the actuator cover. There is no need to cover it, which can reduce the height of the device body.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of an optical pickup device according to the present invention will be described below with reference to FIGS.

In FIGS. 4 to 6, reference numeral 1 denotes the whole of an example of the optical pickup device, and 2 is attached to the above-mentioned bracket or the like, and is arranged in the approaching direction or the separating direction with respect to the turntable 70 along the guide shafts 68a and 68b. The objective lens accommodating portion 3 is formed in one half and the optical system accommodating portion 4 is formed in the other half of the slide base that is moved to a guide shaft hole that is inserted into the guide shaft 68a at one end. 5
On the other end side, guide grooves 6 that are substantially U-shaped in side view are formed so as to be engaged with the guide shafts 68b.

The objective lens accommodating portion 3 of the slide base 2 is formed in a concave housing open to the upper surface side, and a biaxial actuator 12 holding an objective lens 11 is installed in the objective lens accommodating portion 3.

As shown in FIG. 1, the biaxial actuator 12 includes a focus coil 14 and a tracking coil 1 on a lens holder 13 which holds an objective lens 11.
The bobbin 16 on which the bobbin 5 is wound is attached, and the bobbin 1
6 is inserted into a yoke 19 to be fixed upright to an actuator substrate 17 and joined to a magnet 18 so as to be movable in the axial direction and rotatable in the axial direction.
3 is a support 20 fixed to the actuator substrate 17
It is supported movably in the vertical and horizontal directions by four spring wires 21 fixed in the diaphragm spring portion 21a at the base end and parallel in the vertical and horizontal directions.

The terminals of the focus coil 14 and the tracking coil 15 of the biaxial actuator 12 are led out to the end face of the lens holder 13 opposite to the lens holding section, and lead to the terminal section 22 fixed to the outer end face of the support 20. An end 23a of a flexible printed wiring board 23 as a lead wire for supplying a control current is fixedly connected to the terminal portion 22.

The biaxial actuator 12 holding the objective lens 11 configured as described above is accommodated in the objective lens accommodating portion 3 of the slide base 2 and an actuator substrate 17 is fixedly screwed on the bottom surface thereof, and the flexible print is performed. The wiring board 23 is led out of the objective lens housing 3.

In the configuration of the present embodiment, the biaxial actuator 12 holding the objective lens 11 in this manner
The objective lens accommodating section 3 for accommodating
In order to protect the shaft actuator 12, a peripheral wall portion 7 having a height such that the lens holder 13 and the support body 20 and the like do not project is integrally formed in a frame shape. At a portion of the peripheral wall portion 7 corresponding to the objective lens 11, a projecting wall 7 a having substantially the same height as the highest elevation of the objective lens 11 is formed so as to project therefrom.
1 is provided to protect the flexible printed wiring board 23 from the support 2.
A vertical cut-out port 7b is formed so that it can be drawn out in a state where it is connected to the 0 terminal section 22, that is, in a vertical position. Thereby, the flexible printed wiring board 23 can be led out without being twisted.

In this way, the peripheral wall portion 7 is provided in the objective lens housing portion 3.
Since the slide base 2 is formed to project, in the movement of the slide base 2 in the direction along the aforementioned guide shafts 68a and 68b,
There is no risk that each member of the biaxial actuator 12 will come into contact with other members, and since the disk cartridge or the disk is prevented from hitting the objective lens 11, the biaxial actuator 12 is protected without being covered by a cover. Thus, the actuator cover 25 that covers the objective lens housing 3 can be configured to only cover the peripheral edge. That is, as shown in FIG. 2, FIG. 4 and FIG. 6, the actuator cover 25 is substantially planar view U which covers a substantially semi-peripheral portion of the objective lens housing portion 3 on the side opposite to the side on which the objective lens 11 is located. Fitting portions 25a and 25b that are formed in a letter shape and that are bent downward in a substantially U shape to fit the peripheral wall portion 5 of the objective lens housing portion 3 are formed. Engaging pieces 25a ₁ , 25 having outer side pieces 25a and 25b extending downward and having engaging portions.
b ₁ is formed, and an engaging piece 25c having an engaging portion is bent downward at a substantially central portion of the rear edge of the rear side portion, and the engaging pieces 25a ₁ , 25b ₁ and 25c are formed by the engaging pieces 25a ₁ , 25b ₁ and 25c. It is adapted to be engaged with the slide base 2.

The actuator cover 25
Is a fitting portion 25 corresponding to the rear half of the objective lens housing 3.
a and 25b are fitted to the peripheral wall portion 7, and the engagement pieces 25a
By fitting the _first , 25b ₁ and 25c into the slide base 2, the peripheral edge of the rear half of the objective lens housing 3 is covered, and the movable side of the biaxial actuator 12 is opened.

Since the cover is not located on the movable portion of the biaxial actuator 12, the height of this portion is reduced, the height of the optical pickup device 1 is reduced, and the moving space can be reduced. , Optical disc reproducing device, magneto-optical disc recording and reproducing device overall miniaturization,
The thickness can be reduced.

The optical system housing 4 formed in the other half of the slide base 2 is open to the lower surface side opposite to the above-mentioned objective lens housing 3 and communicates with the objective lens housing 3 from the other end surface side. Is formed.

As shown in FIG. 3, the optical system accommodating portion 4 is
As the optical system member 30, from the other end surface side of the slide base 2 to the objective lens housing portion 3 side, a semiconductor laser 31 as a laser light source and a grating 33 incorporating an astigmatism correction plate (hereinafter referred to as AS correction plate) 32 are incorporated. , A beam splitter 34, a collimator lens 35, and a prism mirror 36 corresponding to the objective lens 11, and a deflection prism (Wollaston prism) from the beam splitter 34 to the photodetector 37 side mounted on one side surface of the slide base 2. ) 38, and a cylindrical lens (multi-lens) 39.

The optical system member 30 thus constructed is
As shown in FIG. 7, the laser light flux emitted from the laser 31 passes through the AS correction plate 32, then passes through the beam splitter 34, is converted into parallel light by the collimator lens 35, is refracted by the prism mirror 36, and is objective lens. A small spot is focused on the information recording surface of the disk D by 11 and is incident. The reflected light from the information recording surface on the disk D returns through the same optical path as that of the incident light, passes from the beam splitter 34 through the deflection prism 38 and the cylindrical lens 39, and is guided to the photodetector 37. The signal is reproduced by capturing the intensity change of the reflected light.

Further, when recording / reproducing this information, the laser spot must always accurately capture the track on the disk even if the disk varies, so that the above-mentioned 2
By driving the axial actuator 12, the objective lens 11 is made to follow the fluctuation of the disk.

The optical system member 30 which is constructed as described above and which is housed in the optical system housing portion 4 of the slide base 2 is adhered and fixed by an adhesive, and a part of the members, that is, the beam splitter 34, the deflection prism 38, A shield plate 40 is in contact with the cylindrical lens 39.

In this embodiment, the hard printed wiring board 41 is fixed to the lower surface of the other half of the slide base 2 to close the opening of the optical system housing 4.

On this hard printed wiring board 41, a required wiring pattern 42 is formed and a connector 43 for connecting a flexible wiring board for lead wiring is attached.
In addition, land portions 42a, 42b, 42c are formed and exposed as required detection contacts on the wiring pattern 42.

Further, in the hard printed wiring board 41, adjusting holes 45 and 4 for adjusting the above-mentioned optical system member 30 are provided.
6 is formed, and one adjustment hole 45 is formed horizontally long to adjust the grading 33.
The other adjustment hole 46 is formed in a circular shape and has a function as a guide for an eccentric driver that adjusts the cylindrical lens 39.

As described above, the open portion of the optical system accommodating portion 4 of the slide base 2 is closed by the hard printed wiring board 41, so that a dustproof measure is provided between the respective members of the optical system member 30 accommodated in the optical system accommodating portion 4. Is almost complete, damage and dropout of the optical system member 30 are reliably prevented, and the optical path is always maintained in a normal state.

Further, the hard printed wiring board 41 is
Since the connector 43 is attached and the flexible printed wiring board for lead wiring is connected, the connection with the external circuit can be easily performed without any restriction.

Further, since the land portions 42a, 42b, 42c are formed on the wiring pattern 42 of the hard printed wiring board 41, a test current is supplied to the wiring pattern 42 by abutting the power supply terminal on the land portion 42a. ,
The objective lens 11 can be corrected, and the land portion 42
The operation inspection can be easily carried out by bringing the detection terminals into contact with b and 42c.
Since a, 42b, and 42c are formed on the hard printed wiring board 41, the power supply terminal, the detection terminal, and the like can be contacted stably and reliably.

Further, since the hard printed wiring board 41 is mounted on the slide base 2 by screwing it with the screw 47, the mounting and positioning can be accurately performed and the mounting can be surely and easily carried out, and the risk of accidental detachment can be eliminated. To be done.

In this example, the slide base 2
A rack member 51, to which a rotary screw shaft of a feed stepping motor is screwed as a feed mechanism 50, is attached to one end of the spring member 52 by a spring member 52 and is elastically engaged with the rotary screw shaft so that a stable feed force can be obtained. Is being transmitted.

Although the embodiment of the present invention has been described above, the present invention is not limited to this example. For example, the spring wire supporting type is used as the supporting mechanism of the objective lens of the actuator. Instead, other configurations such as a hinge arm type configured by an arm having a hinge structure, a leaf spring type using a leaf spring, and the like can be applied.

Further, the optical system is not limited to the one having the above-mentioned constitution, and another constitution may be applied.
The slide base is die cast from an aluminum alloy, but can be made from other materials, and the shape is not limited to that shown in the drawings.

[0038]

As described above, in the optical pickup device according to the present invention, the concave portion in which the actuator supporting the objective lens is arranged, and the peripheral wall for protection which protects the actuator by being provided in the peripheral portion of the concave portion over a predetermined range. Since the actuator is directly protected on the side of the slide base by the provision of the slide base having the parts, it is not necessary to cover the movable part with the actuator cover, which reduces the height of the device main body. In addition, the moving space can be reduced, and the overall size and thickness of the optical disk reproducing device, the magneto-optical disk recording / reproducing device, etc. can be reduced. Further, the actuator cover can be formed in a small size, which is advantageous in terms of cost.

[Brief description of drawings]

FIG. 1 is a perspective view of an example of an objective lens actuator portion of an optical pickup device according to the present invention.

FIG. 2 is a perspective view of an actuator cover attached to the objective lens actuator portion shown in FIG.

FIG. 3 is an exploded perspective view of an example of an optical system portion of the optical pickup device according to the present invention.

FIG. 4 is a plan view of an example of an optical pickup device according to the present invention.

5 is a bottom view of the optical pickup device shown in FIG.

6 is a right side view of the optical pickup device shown in FIG.

FIG. 7 is an optical path diagram of an example of an optical pickup device according to the present invention.

FIG. 8 is a partially separated perspective view of a conventional optical magnetic head device.

[Explanation of symbols]

2 slide base, 3 objective lens housing, 4 optical system member housing, 7 peripheral wall, 7a projecting wall, 7b outlet, 11 objective lens, 12 biaxial actuator,
13 lens holder, 20 support, 22 terminal part,
25 actuator cover, 30 optical system members, 4
1 hard printed wiring board, 42 wiring pattern, 4
2a, 42b, 42c Land portion, 43 connector

Claims (5)

[Claims] 1. A slide base having a concave portion in which an actuator supporting an objective lens is arranged, and a protective peripheral wall portion provided in a peripheral portion of the concave portion over a predetermined range to protect the actuator. An optical pickup device characterized by the above. 2. The optical pickup device according to claim 1, wherein the protective peripheral wall portion is provided so as to surround the objective lens and the actuator. 3. The optical pickup device according to claim 1, wherein a projection wall for protecting the objective lens, which is substantially equal to or slightly higher than the height when the objective lens is raised, is formed on the protection peripheral wall portion. 4. The optical pickup device according to claim 1, wherein a slit-shaped outlet through which a flexible printed wiring board for lead wiring of the actuator is inserted in a vertical position is provided on a side surface side of the recess. . 5. The optical pickup device according to claim 1, wherein an actuator cover is attached to the slide base to cover at least a portion of the recess other than a movable portion of the actuator.