JP2006004578A - Guide structure for driving optical element, and optical element driving unit and optical pickup device provided with the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a guide structure which can miniaturize an optical element driving unit and an optical pickup device. <P>SOLUTION: This optical element driving unit 1 is provided with the guide structure which moves a correcting lens b109 (an optical element) in a uniaxial direction while supporting it. The guide structure comprises a lead screw 4 (a main shaft), a main bearing section 6, a bent section 9 in which a base 8 (a board) is bent and formed, a jackshaft 9a which is a part of the bent section, a sub-bearing section 11, an opening 10 formed in the bent section so as to adjoin the jackshaft 9a, and the base 8 mounting them. And a jackshaft sandwiching section 11b for sandwiching the jackshaft 9a is inserted in the opening 10. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a guide structure for moving an optical element provided in an optical pickup device for recording / reproducing information on / from an optical recording medium in one axial direction. The present invention also relates to an optical element driving unit and an optical pickup device having this guide structure.

  An optical pickup device for recording / reproducing information on / from an optical recording medium such as an optical disc includes an optical element such as an objective lens, a collimating lens, various correction lenses, or an optical pickup including these lenses. ing. Some of these optical elements are integrated with a drive unit for moving the position so that the position can be adjusted to an optimum position when recording or reproducing information. A structure including this optical element and its drive unit is called an optical element drive unit.

  Some of these optical element drive units have a structure that can move in one axial direction by having a main shaft and a sub shaft. A mechanism that includes the main shaft and the sub shaft and structures (base, bearing portion, etc.) provided in the peripheral portions thereof and is involved in the movement of the unit is called a guide structure for driving the optical element.

  Here, a guide structure of an optical element driving unit provided in a conventional optical pickup device will be described with reference to Patent Documents 1 and 2. FIG. 5 is a perspective view showing a schematic configuration of the optical element driving unit 130 provided in the optical pickup device described in Patent Document 1. As shown in FIG. FIG. 6 is a perspective view showing a schematic configuration of the optical element driving unit 140 provided in the optical pickup device described in Patent Document 2. As shown in FIG.

  As shown in FIG. 5, the optical element driving unit 130 described in Patent Document 1 has a sub-shaft 136 formed by a bent portion 134 obtained by bending a part of a base 131. In this optical element drive unit 130, the secondary shaft 136 is adapted to the secondary bearing portion 135 of the optical element holder (here, optical pickup) 137 having the primary bearing portion 132, and the primary bearing portion 132 is attached to the base 131. A guide structure is formed in conformity with the main shaft 131 formed. As a result, an optical element (not shown) provided in the optical element holder 137 has a structure that can move in one axial direction.

As shown in FIG. 6, the optical element driving unit 140 described in Patent Document 2 is bent at two locations in which a part of the base 141 is bent at right angles to the axial direction of the main shaft 143 (indicated by the arrow A). The parts 144 and 144 fix the auxiliary shaft 146. In this optical element driving unit 140, the secondary shaft 146 is adapted to the secondary bearing portion 145 of the optical element holder (here, optical pickup) 147 having the primary bearing portion 142, and the primary bearing portion 142 is attached to the base 143. A guide structure is formed in conformity with the main shaft 143. Thus, the optical element provided in the optical element holder 147 has a structure that can move in one axial direction.
JP 9-91891 A (publication date: April 4, 1997) JP 9-282672 A (publication date: October 31, 1997)

  Incidentally, the guide structure provided in the optical element driving unit shown in FIGS. 5 and 6 has the following problems. Here, the problem will be described with reference to FIG. 7 or FIG. FIG. 7 is a side view showing a partial side surface of the guide structure provided in the optical element driving unit shown in FIG. FIG. 8 is a side view showing a partial cross section of the guide structure provided in the optical element driving unit shown in FIG.

  In the prior art of Patent Document 1, as shown in FIG. 7, since the auxiliary shaft is formed by bending two portions of the base 131, there is inevitably a distance a <b> 1 between the bent portion 134 of the base and the auxiliary bearing portion 135. Arise. This distance and the area resulting from the length of the device in the direction of the principal axis (arrow A in FIG. 5) and the resulting volume cannot be removed completely, which is disadvantageous when the optical element drive unit is downsized. Further, in such a configuration, it is necessary to newly provide a member (for example, a stopper) that restricts the movement of the optical element driving unit at both ends of the movement range of the secondary shaft. In addition to being a problem in making it easier, the manufacturing process is complicated.

  In the prior art of Patent Document 2, as shown in FIG. 8, in order to fix the auxiliary shaft 146, the base is bent at right angles to the main axis direction (arrow A in FIG. 6) to form the auxiliary bearing portion 144. Therefore, a distance a2 between the auxiliary bearing portion 145 and one end of the bent portion 144 is inevitably generated. The area resulting from this distance and the length of the apparatus in the principal axis direction and the volume that accompanies it cannot be completely removed, which is disadvantageous when the optical element drive unit is downsized. Similarly to Patent Document 1, it is necessary to newly provide a member for restricting the movement of the optical element driving unit, which not only causes a problem in reducing the size of the optical element driving unit, but also complicates the manufacturing process. There are also problems.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a guide structure for an optical element driving unit that can reduce the size of the optical element driving unit, and an optical element on which the optical element is mounted. It is to provide a drive unit and an optical pickup device.

  As a result of intensive studies in view of the above problems, the present inventor has made the guide structure of the optical element driving unit mounted on the optical pickup into a structure in which a part of the auxiliary bearing portion is inserted into the opening formed in the bent portion. Thus, it has been found that the area resulting from the distance from the auxiliary bearing portion to the end of the bent portion and the length of the device in the principal axis direction can be reduced. Furthermore, the inventors of the present application have found that it is possible to develop a miniaturized optical element driving unit that does not require a new movement limiting member by processing the opening with high accuracy and having a movement limiting function. It came to complete.

  That is, in order to solve the above problems, the guide structure according to the present invention is provided in an optical element driving unit in which an optical element is movably arranged, and is uniaxial while supporting the optical element in the unit. A guide structure for moving in a direction, comprising: a holding shaft that holds the optical element movably in one axial direction on a base substrate; and a bearing portion that is a bearing of the holding shaft. The holding shaft is formed by a part of a bent portion formed by bending the substrate, and the bent portion is provided with an opening adjacent to the holding shaft, and the bearing portion. A part of the shaft holding portion for supporting the holding shaft provided on the insertion portion is inserted into the opening.

  The guide structure of the present invention is provided in the optical element driving unit, and moves in one axial direction while supporting the optical element. This guide structure includes a base plate on which a support shaft and optical elements are placed, a holding shaft provided on the base plate, and a bearing portion thereof.

  In this guide structure, the holding shaft is formed by a part of a bent portion formed by bending the substrate at a substantially right angle. The bent portion is provided with an opening adjacent to the holding shaft, and a part of the shaft clamping portion provided in the bearing portion is inserted into the opening.

  Specifically, the two shaft clamping portions are provided so as to be supported with the holding shaft interposed therebetween. One of the two shaft clamping portions is inserted into the opening. In addition, the other shaft clamping part is arrange | positioned adjacent to the edge part of the said bending part.

  According to said structure, the shaft clamping part of a support shaft and a bearing part can be arrange | positioned on the substantially same plane as a bending part. Therefore, in the guide structure of the optical element driving unit, the distance (for example, a1 and a2 shown in FIGS. 7 and 8) from the support shaft to the end surface (the outer surface of the bent portion) of the guide structure can be reduced. By providing this guide structure in the optical element driving unit, the size of the optical element driving unit can be reduced without changing the size of the optical element and the movement range of the optical element.

  Furthermore, by processing the opening with high accuracy, it is possible to provide a function of restricting the movement of the optical element driving unit. Accordingly, in the guide structure, it is not necessary to newly provide a stopper for restricting the movement of the optical element driving unit, so that the optical element driving unit can be further reduced in size. In addition, the above structure has a simple structure as compared with the structure in which the optical element driving unit has a stopper, so that the manufacturing process can be simplified and the cost can be reduced.

  In the guide structure according to the present invention, the guide structure includes a main shaft that holds the optical element movably in one axial direction on the substrate, a main bearing portion that is a bearing of the main shaft, and the main shaft. And a sub-shaft provided at a position facing the main shaft across the optical element, a sub-bearing portion that is a bearing of the sub-shaft, and the main shaft, and the optical shaft A drive source for driving the movement of the element, and the sub-axis is formed by a part of a bent portion formed by bending the substrate, and the bent portion is adjacent to the sub-axis. An opening is provided, and one of the auxiliary shaft holding portions of the auxiliary bearing portion for supporting the auxiliary shaft with the auxiliary shaft interposed therebetween is inserted into the opening.

  That is, in the above guide structure, the auxiliary shaft is formed by a part of the bent portion obtained by bending the substrate at a substantially right angle, and the bent portion is formed with an opening parallel to the auxiliary shaft. It is the structure that a part of auxiliary bearing part is inserted in the opening part.

  According to the above configuration, by inserting a part of the sub-bearing portion into the opening formed in the bent portion formed by bending the substrate at a substantially right angle, the optical element is interposed therebetween. Further, the distance between the main shaft and the sub shaft can be shortened. By providing this guide structure in the optical element driving unit, the size of the optical element driving unit can be reduced without changing the size of the optical element and the movement range of the optical element.

  In the guide structure of the present invention, it is preferable that the auxiliary shaft is formed including a material different from that of the substrate.

  As described above, if the counter shaft includes a material different from that of the substrate, an optimal material is selected as the different material in order to reduce wear in the sub bearing portion and the counter shaft. be able to. Thereby, the durability of the optical element driving unit is improved.

  In addition, examples of the sub-shaft formed by including different materials include a structure in which a resin material is attached around a base shaft made of the same material as the substrate, as shown in an embodiment described later. be able to. Examples of the method for attaching the resin material to the base shaft include outsert molding, adhesion, and pressure bonding.

  In the guide structure of the present invention, it is preferable that the opening is formed in accordance with the movement range of the optical element.

  According to the above configuration, since the opening is opened in accordance with the movement range of the optical element, the opening can be formed so that the guide structure has a function of restricting the movement of the optical element. it can. Accordingly, in the guide structure, it is not necessary to newly provide a stopper for restricting the movement of the optical element driving unit, so that the optical element driving unit can be further reduced in size. Moreover, since the optical element driving unit has a simple structure as compared with the conventional structure having a stopper, the manufacturing process can be simplified and the cost can be reduced.

  An optical element driving unit according to the present invention includes a guide structure having any one of the structures described above and an optical element, and the optical element moves in one axial direction.

  According to said structure, while being able to reduce an optical element drive unit, durability of the said unit can also be improved or productivity can also be improved.

  In the optical element driving unit of the present invention, the optical element may be a spherical aberration correction lens.

  According to said structure, the optical element drive unit for performing spherical aberration correction provided in the optical pick-up apparatus can be reduced in size. As a result, the size of the optical pickup device itself can be reduced.

  An optical pickup device according to the present invention includes an optical element driving unit having any one of the structures described above.

  According to said structure, since it has said optical element drive unit, the magnitude | size of an apparatus can be reduced in size. Furthermore, it is possible to provide an optical pickup device with improved durability as compared with the prior art.

  In the guide structure of the optical element driving unit of the present invention, the holding shaft is formed by a part of a bent portion obtained by bending the substrate, and the bent portion is formed with an opening parallel to the holding shaft. A part of the shaft clamping portion provided in the bearing portion has a structure inserted into the opening.

  According to said structure, the shaft clamping part of a support shaft and a bearing part can be arrange | positioned on the same plane as a bending part. Therefore, in the guide structure of the optical element driving unit, the distance in the direction perpendicular to the support shaft can be reduced. Thereby, the size of the optical element driving unit can be reduced without changing the size of the optical element and the movement range of the optical element.

  Furthermore, by processing the opening with high accuracy, it is possible to provide a function for restricting the movement of the optical element driving unit. Therefore, in the above guide structure, it is not necessary to newly provide a stopper for restricting the movement of the optical element driving unit, so that the optical element driving unit can be further reduced in size. Further, since the above structure has a simple structure as compared with the structure in which the optical element driving unit has a stopper, the manufacturing process can be simplified and the cost can be reduced.

  Further, if the guide structure of the present invention is used as a guide structure related to the movement of the optical element driving unit and the optical pickup device, the optical element driving unit and the optical pickup device can be reduced in size.

  The embodiment of the present invention will be specifically described with reference to FIGS. 1 to 4, but the present invention is not limited to this.

  In this embodiment, a spherical aberration for correcting a spherical aberration that occurs when reading or recording information is mounted on an optical pickup device that records and reproduces information on an optical recording medium such as an optical disk. An optical element driving unit for driving the correction lens (optical element) will be described. In particular, in the present embodiment, a guide structure provided in the optical element driving unit will be described in detail. In addition, this guide structure is a mechanism for moving in one axial direction while supporting the optical element in the unit, and includes a main shaft and a sub shaft that support the optical element, and a structure ( Base, each bearing part, etc.).

  First, an optical pickup device on which the optical element driving unit is mounted will be described with reference to FIG. FIG. 2 is a perspective view showing the configuration of the optical pickup device 20 on which the optical element driving unit 1 according to the present embodiment is mounted.

  As shown in FIG. 2, the optical pickup device 20 includes a semiconductor laser 100 as a light source, a collimating lens 101, a λ / 2 plate 102, a shaping prism 103, a grating 104, a PBS 105, and a part of a light beam from the semiconductor laser 100. From the detector 106 to detect, the λ / 4 plate 107, the correction lens a108 and the correction lens b109 which are two spherical aberration correction lens groups, the mirror 110, the objective lens 111, the condenser lens 112, the cylindrical lens 113, and the optical disk The detector 114 for detecting the reflected light is provided.

  The optical element driving unit 1 provided in the optical pickup device 20 supports a correction lens b109 as an optical element, and drives the movement of the correction lens b109 in one axis direction.

  Next, the operation of the apparatus when information is recorded / reproduced with respect to the optical disk using the optical pickup apparatus 20 will be described.

  The light beam emitted from the semiconductor laser 100 enters the λ / 2 plate 102 through the collimator lens 101, and the polarization direction is converted here. Thereafter, the incident light is enlarged and shaped by the shaping prism 103. Next, the light beam emitted from the shaping prism 103 is divided into three beams by the grating 104. A part of the divided light beam passes through the PBS 105 and enters the detector 106. The power control of the semiconductor laser 100 is performed according to the amount of incident light. On the other hand, in the PBS 105, most of the remaining light beam that has not entered the detector 106 is reflected and enters the λ / 4 plate 107 by changing its path by 90 degrees. As a result, the light beam is converted into circularly polarized light and then incident on the beam expander. Here, the beam expander means a configuration in which the correction lens a108 is attached to the optical element driving unit 1.

  The beam expander is composed of two spherical aberration correction lens groups, a correction lens a108 and a correction lens b109. Of the two spherical aberration correction lenses, the correction lens b109 disposed on the side closer to the objective lens 111 is attached to the optical element driving unit 1 and can be moved in the optical axis direction (that is, in one axial direction). It has become. Here, the phrase “movable in the one-axis direction” means that it can move in a one-dimensional linear direction.

  The two spherical aberration correction lens groups correct spherical aberration caused by a thickness error of the disk substrate when the optical disk is irradiated with light. Specifically, the optical element drive unit 1 moves the lens b109 in the optical axis direction, and changes the distance between the correction lens a108 and the correction lens b109, thereby converting the parallel light into convergent light or convergent light to obtain a spherical surface. It has a function of correcting aberrations. Although the correction lens b109 on the objective lens 111 side is driven in the present embodiment, the correction lens a108 on the semiconductor laser 100 side may be movable.

  The light beam emitted from the beam expander is reflected by the rising mirror 110 and enters the objective lens 111. The light beam that has passed through the objective lens 111 is condensed on an optical disk (not shown) to form a beam spot. The objective lens 111 is attached to an objective lens actuator (not shown). The objective lens actuator is in a biaxial direction, ie, a focus direction parallel to the optical axis direction of the objective lens 111 and a tracking direction parallel to the radial direction of the optical disk. It is configured to be movable. Then, the reflected light collected on the optical disk by the objective lens 111 is converted in the polarization direction by the λ / 4 plate 107 through the objective lens 111, the rising mirror 110, the correction lens b109, and the correction lens a108. To Penetrate. Thereafter, the reflected light is condensed on the detector 114 by the condenser lens 112 and the cylindrical lens 113, thereby detecting a servo signal and an information signal.

  Next, a more detailed configuration of the optical element driving unit 1 will be described with reference to FIG.

  The optical element driving unit 1 includes an optical element holder 2, a stepping motor (drive source) 3, a lead screw (main shaft) 4, a grip rack 5, a position sensor 7, a base (substrate) 8, and the like. The optical element holder 2 holds one of the correction lenses a and b in the beam expander. In the present embodiment, the lens b109 closer to the objective lens is held.

  In the optical element driving unit 1, a correction lens b109, which is an optical element on the base 8 serving as a base, is disposed. On both sides of the correction lens b109, the correction lens b109 is sandwiched between them. A lead screw 4 as a main shaft and a sub shaft (holding shaft) 9a formed by a part of a bent portion of the base 8 are arranged. The lead screw 4 and the auxiliary shaft 9a are arranged in parallel to each other so as to support an optical element that moves in one axial direction. Further, in the optical element driving unit 1, a stepping motor 3 that drives the movement of the optical element in one axial direction is disposed adjacent to the lead screw 4. The lead screw 4 is supported by a main bearing portion 6 that is a bearing thereof, and the auxiliary shaft 9a is supported by an auxiliary bearing portion (bearing portion) 11 that is a bearing thereof.

  In this optical element drive unit 1, the lead screw 4 that is gear-coupled to the stepping motor 3 is rotated by the rotation of the stepping motor 3 that is a drive source. The rotation of the lead screw 4 is converted into a linear motion in the optical axis direction of the correction lens b 109 via the grip rack 5 attached to the optical element holder 2. The grip rack 5 is a structure in which a rack made of a highly slidable resin such as POM or PPS is attached to the tip of a thin metal having spring properties such as SUS or copper alloy. Then, by supporting the outer diameter of the lead screw 4 with the main bearing portion 6 provided in the optical element holder 2, the lead screw 4 also has a function as a main shaft. Of course, it goes without saying that the main shaft may be provided as a separate member. Further, in order to detect the initial position of the optical element holder 2, the position sensor 7 and the transmissive photo interrupter are provided in the present embodiment, but of course, anything that can detect the position may be used.

Here, the configuration around the auxiliary shaft 9a will be described in more detail.
At the end on the side where the countershaft is provided, a part of the base 8 to which the stepping motor 3 is fixed is bent at a substantially right angle to form a bent portion 9. In this bent portion 9, when the end adjacent to the bent corner portion is the lower end and the end opposite to the lower end is the upper end, the auxiliary shaft 9 a is formed by a part of the bent portion on the upper end side. Is formed. And the opening part 10 is provided in the said bending part 9 so that the subshaft 9a formed in the upper end part side may be adjoined. It can also be said that the opening 10 is arranged in parallel with the auxiliary shaft 9a.

  And this opening part 10 is provided in the auxiliary bearing part 11 provided in the optical element holder 2, and the auxiliary shaft clamping part (shaft clamping part) 11a * 11b for sandwiching and supporting the auxiliary shaft 9a. One of these is inserted. With such a structure, the countershaft clamping portion 11a and the subshaft 9a come into contact with each other under pressure due to the reaction force of the grip rack 5 pressing the lead screw 4, thereby restricting the rotational movement around the main shaft. Can do.

  FIG. 3 shows a partial side surface of the guide structure provided in the optical element driving unit shown in FIG. In this figure, the peripheral part of the auxiliary shaft 9a is shown among the guide structures. As shown in FIG. 3, the auxiliary shaft 9 a is disposed between the two auxiliary shaft holding portions 11 a and 11 b provided in the auxiliary bearing portion 11. That is, as described above, the auxiliary shaft holding portion 11 b located on the side closer to the base 8 out of the two auxiliary shaft holding portions 11 a and 11 b is inserted into the opening 10. As shown in FIG. 3, the auxiliary shaft clamping portion 11a, the auxiliary shaft 9a, the auxiliary shaft clamping portion 11b, and the bent portion 9 are arranged in a straight line.

  By having the above structure, the width of the bent portion 9 protruding from the auxiliary bearing portion 11 as shown in FIGS. 7 and 8 (that is, the distance a1 or a2 in FIGS. 7 and 8) can be eliminated. The width dimension of the optical element driving unit 1 can be shortened. Thereby, the optical element driving unit in which the optical element is mounted on the guide structure can be reduced in size.

  Furthermore, the movement of the optical element parallel to the auxiliary shaft 9a is limited by the end of the opening 10 parallel to the auxiliary shaft 9a by inserting the auxiliary shaft holding portion 11b into the opening 10. Therefore, it is not necessary to provide a separate stopper for limiting the movement of the optical element. As a result, the optical element driving unit can be further reduced in size and a simple structure as compared with a structure having a stopper, so that the manufacturing process can be simplified and the cost can be reduced.

  Furthermore, since the range of movement of the optical element holder 2 in the optical axis direction can be limited by accurately forming the size of the opening 10, the function as a stopper can be reliably achieved. That is, it is preferable that the opening 10 is formed in accordance with the movement range of the correction lens b109. Thereby, the opening part 10 can restrict | limit the movement of an optical element correctly.

  In the present embodiment, the lead screw 4, which is the main shaft, the main bearing portion 6, the bent portion 9 formed by bending the base 8, the auxiliary shaft 9a which is a part of the bent portion, the auxiliary bearing portion 11, The opening 10 is formed in the bent portion so as to be adjacent to the sub-shaft 9a, and the base 8 on which these are placed, and supports the correction lens b109 (optical element) together with the optical element holder 2. The structure in which the correction lens b109 is moved in the optical axis direction (that is, the uniaxial direction) is called a guide structure of the optical element driving unit.

  Next, another example of the guide structure provided in the optical element driving unit according to the present invention will be described with reference to FIG. This figure is a partial side view showing a part corresponding to the guide structure of the optical drive unit shown in FIG. In the guide structure shown in FIG. 4, the sub shaft 12 is not formed of only the same material as the base 8, but is formed including a material different from the base 8 (here, a resin having good slidability). ing.

  That is, in the guide structure shown in FIG. 4, the auxiliary shaft 12 is disposed between the two auxiliary shaft holding portions 11 a and 11 b provided in the auxiliary bearing portion 11, similarly to the guide structure shown in FIG. 3. However, unlike the guide structure shown in FIG. 3, the secondary shaft 12 is not formed only by (a part of) the bent part 9 obtained by bending the base 8, but at a part of the bent part 9. It has a structure in which a resin with good slidability is attached by outsert molding, adhesion, or pressure bonding.

  In this way, by using the sub shaft 12 to which the resin having good slidability is attached by outsert molding, adhesion, pressure bonding or the like, the sub shaft 9a of the guide structure shown in FIG. 3 and the two sub shaft holding portions 11a are provided. -It becomes possible to reduce the friction which arises between 11b. That is, since the surface of the sub shaft 12 is formed of a material suitable for improving the slidability, wear between the sub shaft 12 and the sub shaft holding portions 11a and 11b is reduced, and the durability of the optical element driving unit is reduced. Will be improved.

  In addition, as a material different from the base 8 included in the auxiliary shaft 12, for example, a material such as alumina or chromium oxide or ceramic coating (spraying) can be used in addition to the resin described above. Even when such a material is used, wear with the auxiliary bearing portion 11 can be reduced.

  In addition, the guide structure shown in FIG. 4 is similar to the guide structure shown in FIG. 3 described above. Of the two auxiliary shaft holding portions 11a and 11b, the auxiliary shaft holding portion 11b located closer to the base 8 is opened. It is inserted in the part 10. And the countershaft clamping part 11a, the countershaft 12, the countershaft clamping part 11b, and the bending part 9 are arrange | positioned along with linear form.

  By having the above structure, as described with reference to FIG. 3, the width of the bent portion 9 protruding from the auxiliary bearing portion 11 as shown in FIGS. 7 and 8 (that is, the distance a1 in FIGS. 7 and 8). Alternatively, since a2) can be eliminated, the width dimension of the optical element driving unit 1 can be shortened. Thereby, the optical element driving unit in which the optical element is mounted on the guide structure can be reduced in size.

  Further, since the auxiliary shaft holding portion 11 b is inserted into the opening 10, the movement of the optical element parallel to the auxiliary shaft 12 is limited by the end of the opening 10 that is also parallel to the auxiliary shaft 12. Therefore, it is not necessary to provide a separate stopper for limiting the movement of the optical element. As a result, the optical element driving unit can be further reduced in size and a simple structure as compared with a structure having a stopper, so that the manufacturing process can be simplified and the cost can be reduced.

  Furthermore, since the range of movement of the optical element holder 2 in the optical axis direction can be limited by accurately forming the size of the opening 10, the function as a stopper can be reliably achieved. That is, it is preferable that the opening 10 is formed in accordance with the movement range of the correction lens b109. Thereby, the opening part 10 can restrict | limit the movement of an optical element correctly.

  In the present embodiment, a guide structure for driving a correction lens that corrects spherical aberration as an optical element in a uniaxial direction has been described. In the present embodiment, the optical element drive unit of the present invention has been described by taking a drive mechanism having this guide structure and spherical aberration correction lens as an example. However, since the guide structure of the present invention can be applied to a general mechanism for changing the lens interval, it can also be used for a zoom mechanism of a camera, for example.

  Further, the guide structure of the present invention includes a driving mechanism (for example, an optical element driving unit as shown in FIGS. 5 and 6) for moving the optical pickup itself in an uniaxial direction as an optical element. That is, it can also be used as a guide structure for an optical pickup device. An optical pickup device provided with such an optical element drive unit is also within the scope of the present invention.

  Since the optical element driving unit and the optical pickup device have the guide structure described above as a driving mechanism, the unit and the device can be downsized. In addition, the optical element driving unit and the optical pickup device do not require a separate member such as a stopper for restricting the movement of the optical element, so that the manufacturing process can be simplified and the cost can be reduced. Can do.

  The present invention is not limited to the above-described embodiments, and various modifications can be made within the scope shown in the claims. That is, embodiments obtained by combining technical means appropriately modified within the scope of the claims are also included in the technical scope of the present invention.

  The guide structure of the present invention can be applied to all guide structures that move in the direction of one axis. In particular, the guide structure of an optical pickup device for performing recording / reproduction with respect to an optical recording medium such as an optical disk, and the optical pickup The present invention can be suitably used for a driving mechanism (optical element driving unit) of a spherical aberration correction lens provided inside the apparatus.

It is a perspective view which shows the structure of the optical element drive unit concerning one Embodiment of this invention. 1 is a perspective view illustrating a configuration of an optical pickup device on which an optical element driving unit according to an embodiment of the present invention is mounted. It is a side view which shows the side surface of a part of guide structure with which the optical element drive unit shown in FIG. 1 was equipped. FIG. 7 is a side view showing another example of the guide structure according to the present invention and showing a side surface of a part of the guide structure provided in the optical element driving unit shown in FIG. 1. It is a perspective view which shows the structure of the optical element drive unit which concerns on a 1st prior art example. It is a perspective view which shows the structure of the optical element drive unit which concerns on a 2nd prior art example. It is a side view which shows the side surface of a part of guide structure with which the optical element drive unit shown in FIG. 5 was equipped. It is a side view which shows the side surface of a part of guide structure with which the optical element drive unit shown in FIG. 6 was equipped.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Optical element drive unit 2 Optical element holder 3 Stepping motor (drive source)
4 Lead screw (spindle)
6 Main bearing (bearing)
8 Base (substrate)
9 Bending part 9a Secondary shaft (holding shaft)
10 Opening 11 Sub bearing (bearing)
12 Secondary shaft (holding shaft)
11a Secondary shaft clamping part (shaft clamping part)
11b Secondary shaft clamping part (shaft clamping part)
20 Optical pickup device 108 Correction lens a
109 correction lens b (optical element, spherical aberration correction lens)

Claims (7)

An optical element is provided in a movable optical element driving unit, and is a guide structure for moving in one axial direction while supporting the optical element in the unit,
On the base substrate,
A holding shaft that holds the optical element movably in one axial direction, and a bearing portion that is a bearing of the holding shaft;
The holding shaft is formed by a part of a bent portion formed by bending the substrate,
The bent portion is provided with an opening adjacent to the holding shaft,
A guide structure characterized in that a part of a shaft holding portion for supporting the holding shaft provided in the bearing portion is inserted into the opening. The above guide structure
A main shaft that holds the optical element movably in one axial direction on the substrate, and a main bearing portion that is a bearing of the main shaft;
A sub-shaft parallel to the main shaft and provided at a position facing the main shaft across the optical element, and a sub-bearing portion which is a bearing of the sub-shaft;
A drive source coupled to the main shaft and driving the movement of the optical element;
The secondary shaft is formed by a part of a bent portion formed by bending the substrate,
The bent portion is provided with an opening adjacent to the auxiliary shaft,
The guide structure according to claim 1, wherein one of the auxiliary shaft holding portions of the auxiliary bearing portion for supporting the auxiliary shaft with the auxiliary shaft interposed therebetween is inserted into the opening.   The guide structure according to claim 2, wherein the auxiliary shaft is formed to include a material different from that of the substrate.   The guide structure according to claim 1, wherein the opening is formed in accordance with a movement range of the optical element. A guide structure according to any one of claims 1 to 4 and an optical element,
An optical element driving unit, wherein the optical element moves in one axial direction.   6. The optical element driving unit according to claim 5, wherein the optical element is a spherical aberration correction lens.   An optical pickup device comprising the optical element driving unit according to claim 5.

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