KR20060093527A - Optical pickup actuator - Google Patents

Abstract

According to the present invention, the inner circumferential angle formed by the two first suspension wires provided on both sides of the bobbin and the outer circumferential angle formed by the two second suspension wires are adjusted differently without using a separate tilt driving means. A simple and inexpensive optical pickup actuator that improves the tilt response.

Suspension Wire, Inner Circle, Outer Circle, Between Angle, Special Disc

Description

Optical pick-up actuator {OPTICAL PICKUP ACTUATOR}

1 is a perspective view of a conventional optical pickup actuator,

2 and 3 are a perspective view of a plate and a hat shade disk,

4A and 4B are diagrams for showing the tilt change amount of a general optical pickup actuator,

5 is a perspective view of an optical pickup actuator according to the present invention;

6 is a view of the optical pickup actuator according to the present invention of FIG.

7 is an operation diagram of an actuator of the optical pickup device according to the present invention for a disc;

8 is an operation diagram of an actuator of the optical pickup device according to the present invention for a hathead disk;

9 and 10 show another embodiment of the optical pickup apparatus according to the present invention.

* Description of the major symbols in the drawings *

20: Optical pickup actuator 11: objective lens

12: bobbin 13: wire holder

14: Side PC 15: Connector

16: Focusing coil 17: Tracking coil

18: Magnet 19: PC Plate

21: York Plate 22: Center Ball

30: first suspension wire 31: second suspension wire

32: inner circumference 33: outer circumference

34: angle A: dish disk

B: hat

The present invention relates to an optical pickup actuator, and more particularly, by adjusting the angle of the suspension wires provided on both sides of the bobbin of the optical pickup actuator to allow the optical pickup actuator itself to be tilted at a specific angle. The present invention relates to an optical pickup actuator which has improved tilt response to a special disk such as a fluorescent disk.

In general, an optical pickup device is a device for reproducing signals recorded on various optical disks or recording signals on the optical disk. The optical pickup device is assembled to a main shaft and a minor shaft provided on the deck panel of the optical driver, and reciprocates along the axial direction. The signal recorded on the optical disc is reproduced or the signal is recorded on the optical disc. The optical pickup device is an optical pickup actuator coupled to the main axis and the minor axis and reciprocating along the axial direction, and an optical pickup actuator installed at an upper surface of the base and converging the incident light beam while moving together with the base to focus on one point of the optical disk. It is composed.

The optical pickup actuator drives the objective lens in the optical axis direction (focusing direction) and / or the radial direction of the optical disk (tracking direction) to compensate for focusing or tracking errors of the objective lens so that the optical beam passing through the objective lens is Refers to a device that forms an accurate spot on a track.

Referring to FIG. 1, a conventional optical pickup actuator 10 will be schematically described. The bobbin 12 mounted with the objective lens 11 has one end penetrated through the wire holder 13 and soldered to the PCB plate 19. The other end is configured to be supported to be lifted by four suspension wires 30 and 31 soldered to the side PCs 14 bonded to the long sides of the bobbin 12, respectively, and the four suspension wires 30, The power applied to the focusing coil 16 and the tracking coil 17 through 31 drives the bobbin 12 in the focusing and tracking direction by interacting with the provided magnet 18, thereby providing the bobbin 12 with the bobbin 12. The mounted objective lens 11 is driven, thereby correcting the focusing and tracking errors of the objective lens 11 due to internal and external shocks or vibrations of the optical disc player, thereby forming accurate spots on the optical disc.

On the other hand, due to the rapid expansion of the DVD market, the tilt driving device of the optical pickup actuator of the DVD player is also developing exponentially. In the Chinese market, however, video CDs have become available without going through a video player, and now DVD players are replacing the market. Therefore, in the disc market, cheap DVD is rapidly spreading on the basis of the existing CD market, and such a disc is imported to Korea in a substantial amount. However, these DVDs are inexpensive, but there are many disc or disc-shaped discs out of specification, and there is an urgent need for optical pickups of optical disc players that can be easily and easily applied to such discs.

The cross section of such a special disk is shown in Figs. In particular, Fig. 2 shows a cross section of the dish-shaped disk A, and Fig. 3 shows a cross section of a hat-shaped disk B. The characteristic of such a special disk is that the deflection in the center region of the disc can be neglected, but the deflection in the outer periphery can not be ignored. Typically, a special disk has a warp property of about 0.5 to 1 degree as shown in the figure.

However, when the conventional optical pickup actuator 10, which does not have a separate tilt driving device as shown in Fig. 1, moves from the center of the special disks A and B to the outer diameter portion, the special disks A and B Because of the warpage phenomenon, the focusing error of the objective lens becomes large, and there is a problem that the light beam focused by the objective lens cannot form an accurate spot at a point on the track of the optical disk. That is, the conventional optical pickup actuator, as shown in Figures 4 (a) and (b), in order to form an accurate spot with respect to the optical disk during the focusing operation, the objective lens to move in the state as parallel to the optical disk as possible The change amount of the tangential tilt (Fig. 4 (a)) and the change amount of the radial tilt (Fig. 4 (b)) are managed and designed to be within an appropriate value. In this case, for the special disc (particularly, its outer diameter portion) exhibiting the warp property of about 0.5 ° to 1 °, the amount of tilt change of the objective lens does not correspond to the amount of warp change of the disc, so that an accurate spot is provided on the optical disc. There was a problem that it could not be formed.

That is, as described above, when warping or the like occurs in the optical disk, the laser beam irradiated from the objective lens obliquely touches the signal surface, and thus the focus of the laser beam is enlarged in an elliptical shape and the signal is read by crosstalk. This becomes unclear and causes a problem that the image quality deteriorates in the reading of the video signal.

On the other hand, as a way to solve this problem, by providing a separate tilt driving means to move the entire optical pickup actuator or only the optical pickup driving unit to perform the tilt correction of the objective lens for the tilt tilt of the optical disk. Optical pick-up actuators have been known, but optical pick-up actuators with separate tilt correction means are expensive as a whole and have the disadvantage of increasing the volume of the apparatus.

Therefore, in order to solve the above problems, there is a need to devise a simple method that can cope with the warping of the optical disk described above without providing a separate tilt correction means.

An object of the present invention is to solve the above problems, and by simply adjusting the angle of the suspension wire provided on both sides of the bobbin without a separate tilt driving means, it is simple to improve the tilt response to the special disk It is to provide an inexpensive optical pickup actuator.

The optical pick-up actuator of the present invention for achieving the above object, the first of which is first soldered to the side PC ratio of the bobbin and the other end is provided in the inner circumferential direction of the disk fixed to the PCB plate through the connection hole of the wire holder A suspension wire and two second suspension wires provided in an outer circumferential direction; An objective lens mounted on an upper surface of the center, a focusing coil and a tracking coil located on an outer circumferential surface, and bobbins having side PC ratios mounted on both sides of the long side, and a bobbin which can be directly soldered to the coil end; In the optical pickup actuator comprising a yoke plate having a center hole drilled in the center and spaced apart from the inner yoke and the outer yoke on the left and right sides of the center hole, the inner circumference formed by the two first suspension wires and the two agents 2The outer periphery of the suspension wire is formed by different from each other,

The inner circumferential angle formed by the two first suspension wires is in a parallel or diverging direction, and the outer circumferential angle formed by the two second suspension wires is formed in a parallel or converging direction, and the inner circumference formed by the two first suspension wires is formed. The angle is formed to have a larger value than the outer circumferential angle formed by the two second suspension wires.

 The above object of the present invention will become more apparent from the preferred embodiments of the present invention described below with reference to the accompanying drawings, by those skilled in the art.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

Figure 5 is a perspective view of the optical pickup actuator according to the present invention, Figure 6 is a view of the optical pickup actuator according to Figure 5 from the inner circumferential direction of the disk, Figure 7 of the optical pickup actuator according to the present invention for a disc 8 is an operation diagram of the optical pickup actuator according to the present invention on a hat disk, and FIGS. 9 and 10 show another embodiment of the optical pickup actuator according to the present invention. For convenience, the same reference numerals are used for the same components as in the prior art.

The optical pickup actuator 20 according to the present invention has an inner circumference formed by two first suspension wires 30a and 30b provided on both sides of the bobbin 12 and an outer circumference formed by two second suspension wires 31a and 31b. It is characterized in that the tilt inclination of the optical disc can be corrected according to the degree of warpage of the optical disc by varying the sizes.

5 and 6, the technical features of the optical pickup actuator 20 according to the present invention will be described. The optical pickup actuator 20 according to the present invention includes two first suspension wires 30a and 30b of the suspension wire. The inner circumferential angle 32 is formed to be larger than the outer circumferential angle 33 formed by the two second suspension wires 31a and 31b so that the tilt according to the inclination of the optical disk can be corrected without a separate tilt correction means. It is a technical feature.

One embodiment of the present invention will be described in detail with reference to FIGS. 5 and 6, two first suspension wires 30a and 30b and two second suspension wires 31a positioned in the inner circumferential direction of the disk. One end of the 31b) is soldered to the side PCB 14 provided on the side surface of the bobbin 12, and the other end passes through the connection hole 15 of the wire holder 13 provided on one side of the yoke plate 21. It is fixed to the plate 19 by soldering. The bobbin 12 has an objective lens 11 mounted at the center of the upper surface thereof, and a focusing coil 16 necessary for focusing driving of the objective lens 11 is located on the long side of the outer circumferential surface thereof. The tracking coil 17 necessary for the tracking drive is located. In addition, the side PC ratio 14 is mounted at the center of the long side so that one end of the suspension wires 30 and 31 are soldered. In addition, the side PC 14 is removed and soldered directly to the coil end.

On the other hand, the yoke plate 21 has a central hole 22 perforated so that the light beam emitted from the laser diode passes through the yoke plate 21, and magnetic flux is generated on the left and right sides of the central hole 22 in cooperation with the magnet 18. The inner yoke 23 is provided, and the outer yoke 24 is provided to be spaced apart from the inner yoke 23 so that the magnet 18 is mounted.

The optical pickup actuator 20 according to the present invention configured as described above has two first suspension wires 30a and 30b and two second suspension wires 31a at side PCs 14 provided on both sides of the bobbin 12. , One end of the 31b) is fixed to the other end of the suspension wires 30 and 31 that are soldered and fixed to the PCB 19 by penetrating through the connection hole 15 of the wire holder 13 based on this. By adjusting the position, the size of the inner circumferential angle 32 formed by the two first suspension wires 30a and 30b and the outer circumferential angle 33 formed by the two second suspension wires 31a and 31b are adjusted. Adjust it.

Referring to FIG. 6, the inner circumferential angle 32 and the outer circumferential angle 33 formed by the first suspension wire 30 and the second suspension wire 31 of the optical pickup actuator 20 configured as described above will be described with reference to FIG. 6. The size of the inner circumferential angle 32 formed by the two first suspension wires 30a and 30b formed in the direction is the outer circumferential angle 33 of the two second suspension wires 31a and 31b formed in the outer circumferential direction. Form to have a value greater than the size of. That is, the two first suspension wires 30a and 30b are formed in the direction in which the other end is parallel or diverging, and the two second suspension wires 31a and 31b are formed in the direction in which the other end is parallel or converging. Configure to

For example, the following four cases may occur between the suspension wires 30 and 31 positioned at the upper portion. That is, i) when the wire 30a positioned at the upper end of the first suspension wire 30 and the corresponding second suspension wire 31a are arranged to be parallel to each other, ii) the first suspension wire 30a Is divergent and the corresponding second suspension wire 31a is arranged in parallel, iii) the first suspension wire 30a is arranged in parallel, and the corresponding second suspension wire 31a is arranged to converge. In this case, i) the first suspension wire 30a may be arranged to diverge, and the corresponding second suspension wire 31a may be arranged to converge. In this case, the number may be applied to the lower end portions of the suspension wires 30 and 31. However, even in this case, the four suspension wires 30 and 31 are not parallel to each other. That is, this indicates that the inner circumference 32 formed by the two first suspension wires 30a and 30b always has a larger value than the outer circumference angle 33 formed by the two second suspension wires 32a and 31b.

In addition, in the embodiment of the present invention, the angle 34 between the first suspension wire 30 and the second suspension wire 31 has a certain limit, the angle between which is generally Maintained between 0 ° and 10 °. That is, the wire 30a formed on the upper end of the first suspension wire 30 is up to 5 ° in the diverging direction, and the wire 31a formed on the upper end of the second suspension wire 31 converges. Can be tilted to have a slope up to 5 °. This is possible because the degree of deflection of the disk generally used has a certain limit. However, the above-described values are not always limited and the tiltable angle of the suspension wire may be made larger when the degree of warpage of the optical disk is generated according to the size of the optical disk and the size of the optical pickup actuator. It may be. That is, the optical pickup actuator 20 of the present invention configured as described above is configured to be tilt driven only by focusing driving of the objective lens.

This principle of the invention is illustrated in FIGS. 7 and 8.

Fig. 7 is a diagram showing the operation of the actuator 20 of the optical pickup apparatus according to the present invention with respect to the dish disk A. The optical pickup actuator 20 according to the present invention is a dish disk (not shown) driven by a pickup motor (not shown). The information reproduced on the disc A is read or recorded while reciprocating in the radial direction of A). When the optical pickup actuator is moved from the inner diameter of the dish disk A to the outer diameter, that is, as the dish disk A is gradually bent upward, the surfaces of the objective lens 11 and the disk A gradually become farther away. As a result, a focusing error of the objective lens occurs. After the focusing servo system searches for the focusing error, a current for compensating the focusing error is applied to the focusing coil 16 through the suspension wires 30 and 31 fixed to the PC plates 19. The applied current cooperates with the magnet 18 to generate an electromagnetic force, and the generated electromagnetic force corrects the focusing error by positioning the objective lens parallel to the optical disk surface.

Here, according to the conventional actuator shown in Fig. 1, since the amount of tilt change of the objective lens is within an appropriate value, the objective is corrected so as to correct the focusing error for a disc that exhibits a much larger deflection degree (about 0.5 ° to 1 °). The lens could not be tilted. However, in the present invention, the inner circumference angle 32 formed by the two first suspension wires 30 positioned in the inner circumferential direction of the disk and the outer circumference angle 33 formed by the two second suspension wires 31 positioned in the outer circumferential direction of the disk are formed. By forming larger than), the vertical flow of the second suspension wire 31 can be made larger than the first suspension wire 30. Therefore, when the optical pickup actuator 20 moves along the radius of the dish disk A, the objective lens can be tilted in a path corresponding to the curved curve of the dish disk A. FIG. That is, the driving to correct the tilt error is made only by the driving to correct the focusing error.

On the other hand, the principle that the optical pickup actuator 20 according to the present invention is applied to the sabot disk (B) is the same as the case of the dish disk (A). When the actuator 20 is moved from the inner diameter to the outer diameter of the optical disk, a current for compensating for the focusing error of the objective lens 11 generated as the disk is gradually bent downward is transmitted by the focusing coil system 16. ), The position is corrected so that the objective lens 11 is incident on the light beam perpendicular to the plane of the optical disk by the applied current. Here, the second suspension wire 31 is formed by forming the outer circumferential angle 33 formed by the two second suspension wires 31 smaller than the inner circumferential angle 32 formed by the two first suspension wires 30. It has a large up and down flow rate. Therefore, even in this case, a drive for correcting the tilt error may be formed only by the drive for correcting the focusing error.

In the above-described embodiment of the present invention, in the case of a disc-shaped disc or a hat-shaped disc having a degree of warpage of a disc of 0.5 ° to 1 °, the first suspension wire 30 and the second suspension wire of the present invention ( By making the angle 34 formed by 31 to 1 ° to 1.5 °, desirable focusing driving can be achieved.

On the other hand, the optical pickup actuator according to the present invention can of course also be applied in the case of an ideal disk without bending. That is, even if the optical pickup actuator 20 is moved from the inner diameter to the outer diameter of the optical disk, a focusing error does not occur since there is no significant change in the focusing focal length. Therefore, the optical pickup actuator according to the present invention can be applied not only to a disk without general bending but also to special disks A and B which are inclined upward or downward.

9 and 10 illustrate another embodiment of the present invention. In one embodiment of the present invention, the angle of the suspension wires 30 and 31 is adjusted by the wire holder 13, but the present embodiment is implemented. In the example, it is to be made in the side PC (14) provided on both sides of the bobbin (12). In this case, the suspension wires 30 and 31 are provided with a predetermined angle on the side PC ratio 14 by measuring the inclination angle using a jig to obtain the effect obtainable in the above-described embodiment. To be able. As shown in Fig. 10, even in this case, the inner circumferential angle 32 formed by the two first suspension wires 30a and 30b is smaller than the outer circumferential angle 33 formed by the two second suspension wires 31a and 31b. By making it larger, the tilt tilt corresponding to the degree of warpage of the optical disk can be achieved only by focusing driving of the objective lens.

As described above, according to the optical pickup actuator in which the angle of the suspension wire is adjusted according to the present invention, since the objective lens can perform not only a focusing drive but also a tilting drive when driving the objective lens according to the focusing error, the optical disc Even when the plate is curved in the shape of a plate or a hat, the objective lens can focus the light beam perpendicular to the surface of the curved optical disk. Therefore, not only discs that are not warped, but also special discs can form accurate spots on the disc tracks, so that there is an advantage in that the response to the special discs is improved.

In addition, since the tilt compensation of the special disk is possible without a separate tilt driving means, there is an effect that it is possible to provide a cheap and simple device.

 As such, the present invention is not limited to the embodiments of the present invention described above, and can be freely changed and modified. The free changes of the present invention are not limited to the embodiments of the detailed description described above, and free changes are possible without departing from the claims described below by those skilled in the art.

Claims (5)

Two first suspension wires are provided in the inner circumferential direction of the disk, one end of which is soldered to the side PCB or coil end of the bobbin and the other end penetrates through the connection hole of the wire holder, and is fixed to the PCB plate. Suspension wires; A bobbin mounted with an objective lens on a central upper surface, a focusing coil and a tracking coil wound on an outer circumferential surface, and side PC ratios mounted on both sides of the long side; In the optical pickup actuator comprising a yoke plate having a center hole in the center and spaced apart from the inner yoke and the outer yoke on the left and right sides of the center hole, And an inner circumferential angle formed by the two first suspension wires and an outer circumferential angle formed by the two second suspension wires having different angles. The method of claim 1, The inner circumferential angle formed by the two first suspension wires is formed in a parallel or diverging direction, and the outer circumferential angle formed by the two second suspension wires is formed in a parallel or converging direction, And an inner circumferential angle formed by the two first suspension wires has a larger value than an outer circumferential angle formed by the two second suspension wires. The method of claim 2, And an angle formed between the first suspension wire and the corresponding second suspension wire is between 0 ° and 10 °. The method of claim 1, An inner circumference formed by the two first suspension wires and the two by using a jig to adjust the soldering positions of the side PCBs at which one end of the two first suspension wires and the two second suspension wires are soldered. The optical pickup actuator, characterized in that for adjusting the outer circumferential angle formed by the second suspension wire. The method of claim 1, By adjusting the fixed position of the other end of the two first suspension wires and the two second suspension wires penetrating the connection hole of the wire holder, the inner circumference formed by the two first suspension wires and the two Optical pick-up actuator, characterized in that to adjust the outer circumferential angle formed by the second suspension wire.

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