JP2005285166A - Optical pickup apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical pickup apparatus provided with diffraction grating being easy to attach to an optical system block and being easy to perform angle adjustment. <P>SOLUTION: Diffraction gratings 30, 40 are attached to holders 32, 42 consisting of thin metal plates, and energized to inner wall planes 211a, 212a of a metal block base 21 by a pair of pressing pieces 51, 53 of a leaf spring 50 and held. Also, sliding end planes 37, 47 of the holder 32, 42 are abutted on slid planes 211b, 212b of the block base 21, the diffraction gratings 30, 40 are held turnably for the bock base 21. Therefore, thinning and miniaturizing the optical pickup apparatus can be performed, while angle adjustment of the diffraction grating also can be performed easily. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an optical pickup device, and more particularly to an optical pickup device used for reproducing or recording / reproducing an optical disc such as a CD (compact disc) or a DVD (digital video disc).

  A conventional optical pickup device is disclosed in Patent Document 1 below, for example. In this optical pickup device, the laser light emitted from the laser light emitting element is irradiated onto the optical disc through a diffraction grating, a prism, a collimating lens, a total reflection mirror, and an objective lens. Reflected light from the optical disk is received by the light receiving element through the objective lens, the total reflection mirror, the collimating lens, the prism, the half mirror, and the cylindrical lens.

  This optical pickup device has an optical element fixing block made of a resin molded product to which the above prism, collimating lens, half mirror and cylindrical lens are bonded and fixed, and this fixing block finely adjusts the mounting position and orientation thereof. It is mounted on a metal (aluminum die cast) body frame (pickup base) where possible. In this way, by mounting a plurality of optical elements on the fixing block in a concentrated manner, the optical elements can be easily assembled with high alignment accuracy.

  In this conventional optical pickup device, a diffraction grating 32 is provided between a laser diode 31 as a laser light emitting element and the fixing block 5. This diffraction grating is provided to perform tracking servo detection by a three-beam method using a grating, and generates two sub beams (primary light) in addition to the main beam (zero order light). For this reason, when the diffraction grating is assembled, it is necessary to adjust the relative angle of the sub beam with respect to the main beam by rotating the diffraction grating with respect to the incident light from the semiconductor laser diode. In the conventional optical pickup device, this diffraction grating is bonded to a resin-molded diffraction grating holder by die molding.

JP-A-11-306549

  Incidentally, in order to reduce the size and thickness of the optical pickup device, it is necessary to reduce the size of the diffraction grating. However, if such a resin diffraction grating holder is reduced in size or thickness, the work and adjustment for attaching the diffraction grating holder to the optical pickup device become difficult, and the strength decreases. In addition, since the optical component such as the diffraction grating is located in the vicinity of the driver IC of the laser diode that generates heat, there is a problem that it is easily affected by heat.

  In addition, the optical element fixing block of the conventional optical pickup as described above has a low rigidity because it is a resin molded product. Therefore, a certain amount of thickness is necessary to maintain the strength, and the optical pickup is made smaller and thinner. It was not enough to meet the request. Further, since the optical pickup is disposed near various motor driver ICs in addition to the laser diode driver IC, the optical pickup operates at a high temperature, and thus is easily affected by heat like the diffraction grating. Therefore, in the fixing block for the resin molded product as described above, there is a possibility that misalignment may occur due to a difference in thermal expansion coefficient from that of the metal pickup base.

  SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and its main object is to easily attach and adjust the optical pickup, and to provide an optical pickup including a diffraction grating capable of reducing the size and thickness of the optical pickup device. To provide an apparatus.

  Another object of the present invention is to provide an optical pickup device that is not easily affected by heat.

  To achieve the above object, the present invention provides at least one laser light emitting element, an objective lens that irradiates an optical disc with laser light emitted from the laser light emitting element, and drives the objective lens in a focus direction and a tracking direction. An objective lens actuator, at least one photodiode for receiving reflected light from the optical disc, and a period from when the laser light emitted from the laser light emitting element reaches the objective lens and reflected light from the optical disc A large number of optical elements disposed between the objective lens and the photodiode; an optical system block on which a plurality of optical elements are mounted among the large number of optical elements; the laser light emitting element; the objective lens actuator; The photodiode and the optical system block are provided The optical system block is provided on the pickup base so that the position of the optical system block can be adjusted, and the plurality of optical elements mounted on the optical system block includes at least one optical element. The diffraction grating includes two diffraction gratings, and the diffraction gratings are attached to the optical system block so as to be position-adjustable via attachment means that is detachably attached to the optical system block.

  According to the present invention having the above-described configuration, the diffraction grating is attached to the optical system block so as to be position-adjustable via attachment means that is detachably attached to the optical system block. It is possible to achieve both thinning and easy assembling and position adjustment of the diffraction grating.

  In this case, it is preferable that the attachment means is a leaf spring that is detachably attached to the optical system block. By using such a leaf spring, it is possible to more effectively achieve easy assembly and position adjustment of the diffraction grating.

  Preferably, the diffraction grating is attached to a thin plate-shaped metal holder having a pair of fixing pieces on both sides, and the leaf spring includes at least a pair of pressing pieces, The fixing pieces on both sides of the holder are pressed by the pair of pressing pieces so that the position can be adjusted to the optical system block.

  According to such a configuration, since the diffraction grating is supported by a metal holder rather than a resin, the entire diffraction grating portion including the holder can be made small and thin. For this reason, the optical pickup device can be reduced in size and thickness. In addition, since the diffraction grating is supported by pressing the fixed pieces provided on both sides of the holder with a pair of pressing pieces of a leaf spring, the position of the diffraction grating can be easily adjusted, and the diffraction grating holder is not uniform. Since no force is applied, distortion of the diffraction grating can be prevented over a long period of time.

  Preferably, the metal holder of the diffraction grating has a sliding end surface, and can be rotated through the sliding end surface to a sliding surface provided in the diffraction grating housing portion of the optical system block. Supported by

  According to such a configuration, the diffraction grating is rotated while pressing the sliding end surface provided on the holder against the sliding surface of the mounting portion of the optical system block, thereby easily moving to a predetermined position in the vertical direction of the block. Therefore, the angle of the diffraction grating can be easily adjusted.

  Furthermore, it is preferable that the optical system block is formed of any material selected from the group including zinc, magnesium, aluminum, and an alloy containing two or more thereof. Thereby, rigidity can be improved compared with the case of resin.

  Further, the pickup base is preferably formed from any material selected from the group including zinc, magnesium, aluminum, and an alloy containing two or more thereof. In this case, the optical system block and the pickup base are It is preferably formed from a metal having the same coefficient of thermal expansion. As a result, it is possible to reliably prevent misalignment of the optical system block due to a difference in thermal expansion coefficient.

  According to another aspect of the present invention, a laser light emitting element, an objective lens that irradiates an optical disc with laser light emitted from the laser light emitting element, an objective lens actuator that drives the objective lens in a focus direction and a tracking direction, and A light-receiving element that receives reflected light from the optical disk, and a period from when the laser light emitted from the laser light-emitting element reaches the objective lens, and reflected light from the optical recording disk from the objective lens to the light-receiving element. A plurality of optical elements disposed between the optical elements, an optical system block provided with a plurality of optical elements among the plurality of optical elements, the laser light emitting element, the objective lens actuator, the light receiving element, and the An optical pickup device comprising a pickup base on which an optical system block is mounted, Optics block, characterized in that the thermal expansion coefficient is formed of the same metal material wherein are positioned adjustably mounted on the pickup base, and the optical system block and the pick-up pace.

  According to the optical pickup of the present invention of this aspect, the rigidity of the optical system block can be increased as compared with the case of resin, and the positional deviation of the optical system block due to the difference in the coefficient of thermal expansion is surely prevented. be able to.

  In this case, the metal material is preferably selected from magnesium, zinc, aluminum, and alloys thereof.

  The above-described and other objects, configurations, and effects of the present invention will become more apparent from the following description of preferred embodiments with reference to the drawings.

  The optical pickup device of the present invention will be described below in detail based on preferred embodiments shown in the accompanying drawings.

  FIG. 1 is a plan view showing an outline of an optical pickup device 1 of the present invention. The optical pickup device 1 is a device that irradiates an optical disc (not shown) with laser light and receives reflected light to read data from the optical disc or write data to the optical disc. As shown in FIG. 1, the optical pickup device 1 is generally provided with an objective lens 11 for irradiating an optical disc with a laser beam so as to have a predetermined spot diameter and receiving the reflected light, and the objective lens 11. , An objective lens actuator unit 12 for driving the objective lens in the tracking direction and the focus direction, an optical system block 2 on which a plurality of optical elements are mounted, and a pickup base (which is provided with these components and movable in the radial direction of the optical disc) Housing) 13.

  The optical pickup device 1 is applied to, for example, an optical disc drive mounted on a computer (personal computer), video equipment, audio equipment, or other electronic equipment, and in particular, an optical disc drive capable of reading a plurality of types of optical discs. . Moreover, CD, DVD, etc. are mentioned as an optical disk.

Hereinafter, the configuration of each unit will be described in detail.
In the pickup base 13 shown in FIG. 1, a guide rod (shown by a dotted line) is inserted into a pair of sliding portions 13a and 13a shown in the upper part of the drawing, and along the guide rod via an optical pickup moving mechanism (not shown). It is configured to be movable in the radial direction of the optical disc.

  The pickup base 13 is formed by molding a metal material into a predetermined shape so as to ensure a desired rigidity. Examples of the metal material include various metals such as zinc, magnesium, and aluminum, or alloys thereof.

  A damper base 10 is provided on the side of the sliding portions 13a, 13a of the pickup base 13 (downward in FIG. 1). From the left and right sides of the damper base 10, two upper and lower suspension springs 12a and 12a extend. An objective lens actuator unit 12 including an objective lens 11 is attached to the tip ends of the suspension springs 12a and 12a so as to be positioned above a reflecting mirror (not shown). The objective lens actuator unit 12 is supported by the objective spring 11 so as to be displaceable in the vertical direction (focus direction) and the horizontal direction (tracking direction) via the suspension springs 12a and 12a. That is, the objective lens actuator unit 12 includes a focus coil for focus servo and a tracking coil for tracking servo, and the objective lens 11 and the objective lens actuator unit 12 are driven by appropriately driving these coils. The lens is displaced in the focus direction and the tracking direction, so that focus servo and tracking servo are applied.

  An optical system block 2 is mounted on the side of the objective lens actuator section 12 of the pickup base 13 (downward in FIG. 1) so that the position can be adjusted. Further, a photodiode (light receiving element) 14, a first laser light emitting element 15, and a second laser light emitting element 16 are disposed on the pickup base 13 around the optical system block 2. The first laser light emitting element 15 and the second laser light emitting element 16 are for reproducing or recording / reproducing different types of discs, and irradiate laser beams having different wavelengths. . In the present embodiment, the first laser light emitting element 15 is for CD and the second laser light emitting element 16 is for DVD, but it goes without saying that the present invention is not limited to such a combination.

  2 is a perspective view of the optical system block 2 as viewed obliquely from above, and FIG. 3 is a perspective view of the optical system block 2 as viewed from the back side. In the optical system block 2, the laser light emitted from the first laser light-emitting element 15 or the second laser light-emitting element 16 reaches the objective lens 11, and the return light from the optical disk is transmitted from the objective lens 11 to the photo A plurality of optical elements among a large number of optical elements arranged up to the diode (light receiving element) 14 are incorporated.

  More specifically, the optical system block 2 has a block base 21 for mounting the plurality of optical elements. The block base 21 is formed by molding a metal material into a predetermined shape in which attachment portions and openings for optical components and the like are provided in advance. As the metal material, similar to the pickup base 13, various metals such as zinc, magnesium, and aluminum, or alloys thereof can be used. In this case, the block base 21 and the pickup base 13 are preferably made of the same metal material. Since the block base 21 and the pickup base 13 are arranged near heat-generating components such as driver ICs, they are easily affected by heat. However, these members are made of the same metal material and have the same coefficient of thermal expansion. Accordingly, it is possible to effectively prevent the displacement of the optical system block 2 due to thermal expansion.

  The block base 21 includes a collimator lens 22 provided on the objective lens 11 side (reflecting mirror side), a sensor lens 23 attached at a position corresponding to the photodiode 14, and an objective lens substantially at the center of the block base 21. 11, a front beam splitter 24 provided on the side of the objective lens 11, a rear beam splitter 25 positioned behind the front beam splitter 24 when viewed from the objective lens 11, and a coupling attached at a position corresponding to the first laser light emitting element 15. The lens 26, the first diffraction grating 30 provided at a position corresponding to the first laser light emitting element 15 and provided at a position corresponding to the second laser light emitting element 16. The second diffraction grating 40 is mounted. In this embodiment, these optical elements correspond to the plurality of optical elements described above. However, in the present invention, as long as at least one diffraction grating is incorporated, other optical elements may be used depending on the design and application of the optical pickup device. It goes without saying that the number and arrangement of the optical elements can be appropriately changed.

  In addition, a metal leaf spring 50 for detachably attaching the first and second diffraction gratings 30 and 40 to the block base 21 is detachably attached to the optical system block 2. It is like that. This metal leaf spring 50 constitutes the attachment means of the present invention.

  4 is a perspective view showing a state in which only the first diffraction grating 30 and the second diffraction grating 40 are attached to the block base 21 of the optical system block 2 in the state shown in FIG. FIG. 5 is an exploded perspective view showing the members shown in FIG. 4 separately from the block base 21.

  As shown in FIGS. 4 and 5, the first diffraction grating 30 is accommodated in the accommodating portion (attachment portion) 211 of the block base 21, and the second diffraction grating 40 is accommodated in the accommodating portion (attachment portion) of the block base 21. 212. The leaf spring 50 is configured by processing a steel plate cut into a predetermined shape into a shape as shown in the figure. As will be described later, a pair of pressing pieces 51, 51 are transferred to the accommodating portion 211 and another pair of pressing pieces 51, 51. The pressing pieces 53, 53 are inserted into the housing portion 212 and the mounting piece 56 is inserted into the housing portion 216, so that the pressing pieces 53 and 53 are detachably attached to the block base 21.

  FIG. 6 is an explanatory diagram of the holder 32 of the first diffraction grating 30 shown in FIG. As shown in FIGS. 5 and 6, the first diffraction grating 30 and the second diffraction grating 40 are glass substrates 31 and 41 on which fine grooves with equal intervals are engraved and an aluminum vapor deposition layer is applied, respectively. The glass substrates 31 and 41 are bonded to holders 32 and 42 formed by bending a thin metal plate such as stainless steel into a predetermined shape. Since the first diffraction grating 30 and the second diffraction grating 40 have the same configuration, the first diffraction grating 30 will be described below.

  As shown in FIG. 5 and FIG. 6, the diffraction grating 30 (glass substrate 31) is bonded to the inner (circular) surface 38 of the holder 32 with an adhesive or the like. A hole 36 through which a beam from the first laser light emitting element 15 passes is provided at the center of the holder 32, and a pair of left and right fixing pieces 33 are provided on both sides of the hole 36. The holder 32 has a pair of adjustment pieces 34 for adjusting the angle of the glass substrate 31 and a pair of arcuate sliding end faces on the side end faces (edges) of the portions substantially opposite to the portions where the adjustment pieces 34 are provided. 37. As will be described later, these sliding end surfaces 37 abut against the sliding surface 211b of the accommodating portion 211 so that the holder 32 is positioned with respect to the block base 21, and the rotation direction of the holder 32 is adjusted (the angle of the diffraction grating). Adjustment).

  In the present embodiment, the holder 32 is formed by punching a stainless steel plate having a thickness of about 0.2 mm into a predetermined shape and then bending it into the shape as described above. Since the holder 32 made of such a thin metal plate as described above is used, not only can the holder 32 be miniaturized, but the thickness of the diffraction grating (thickness including the glass substrate) should be 1 mm or less. Compared with the case where a conventional resin holder having a thickness of 2 mm or more is used, the thickness can be reduced to half or less, which contributes to the reduction in thickness and size of the optical pickup.

  Next, a state where the first diffraction grating 30 is housed in the housing portion 211 will be described with reference to FIGS. 7 and 8. As shown in FIGS. 7 and 8, the first diffraction grating 30 is locked by the pair of pressing pieces 51 of the leaf spring 50 in the housing portion 211 of the block base 21. In this locked state, the fixing piece 33 of the holder 32 is urged against the inner wall surface of the block base 21 by the pressing portion 52 of the pressing piece 51, and the outer side surface 35 (see FIG. 6) of the holder 32. Is pressed against the inner wall surface 211 a of the housing portion 211. The first diffraction grating 30 is held in contact with a predetermined position of the block base 21 by the urging of the pressing portion 52.

  On the other hand, the first diffraction grating 30 is positioned in the vertical direction of the block base 21 by the sliding end surface 37 of the first diffraction grating 30 coming into contact with the sliding surface 211 b of the housing portion 211. Since the sliding end surface 37 is formed in an arc shape, the first diffraction grating 30 can be rotated in the arrow direction shown in FIG. 7 while pressing the sliding end surface 37 against the sliding surface 211b. The angle of the diffraction grating can be easily adjusted.

  The configurations of the first diffraction grating 30 and the accommodating portion 211 are the same as the configurations of the second diffraction grating 40 and the accommodating portion 212. The second diffraction grating 40 corresponds to each part of the 40th series, the inner wall surface 211a corresponds to the inner wall surface 212a, and the sliding surface 211b corresponds to the sliding surface 212b.

  Hereinafter, the optical path of the laser beam of the optical pickup device 1 will be described. The CD laser light emitted from the first laser light emitting element 15 is collected by the coupling lens 26, diffracted by the first diffraction grating 30, reflected by the reflecting surface of the rear beam splitter 25, and forward beam splitter. 24 passes through the collimator lens 22 and becomes parallel light. Then, the light is reflected by a reflecting mirror (not shown) and irradiated onto the recording surface (recording layer) of the CD via the objective lens 11.

  Contrary to the above, the reflected light reflected by the recording surface of the CD passes through the objective lens 11, the reflecting mirror (not shown), and the collimator lens 22 in order, and is reflected by the reflecting surface of the front beam splitter 24, and the sensor. Light is received by the photodiode 14 through the lens 23.

  On the other hand, the DVD laser light emitted from the second laser light emitting element 16 is diffracted by the second diffraction grating 40, passes through the rear beam splitter 25 and the front beam splitter 24, and becomes parallel light by the collimator lens 22. . Then, the light is reflected by a reflecting mirror (not shown) and irradiated onto the recording surface (recording layer) of the DVD via the objective lens 11.

  Contrary to the above, the reflected light reflected by the recording surface of the DVD passes through the objective lens 11, the reflecting mirror (not shown), and the collimator lens 22 in order, and is reflected by the reflecting surface of the front beam splitter 24. Light is received by the photodiode 14 through the lens 23.

Hereinafter, the function and effect of the present invention will be described.
Since the diffraction grating is attached to the optical system block by a leaf spring so that the position of the diffraction grating can be adjusted, both the assembly of the optical pickup device and the easy adjustment of the position of the diffraction grating (angle adjustment) can be achieved. In particular, in the case of a diffraction grating, unlike the other optical components, the angle adjustment as described above is required even after being attached to the optical block, and thus such a configuration is very significant.

  Moreover, since the diffraction grating is supported by a holder made of metal such as stainless steel instead of resin, the entire diffraction grating including the holder can be made very small and thin. For this reason, compared with the case where a resin holder is used, the optical pickup device can be further downsized and thinned.

  Furthermore, the diffraction grating is supported on the block base by urging the metal holder provided with the diffraction grating against the metal block base by a leaf spring, so that the diffraction grating is securely held in place. it can. In addition, the metal holder is provided with a pair of left and right fixing pieces, and these fixing pieces are urged against the inner wall of the block base by a pair of pressing pieces of the leaf spring, so that the holder is equally left and right. It is reliably held at a predetermined position by the urging force. In addition, since a non-uniform force is not applied to the diffraction grating, distortion of the diffraction grating can be prevented over a long period of time.

  Furthermore, since the holder is rotated while the sliding end surface provided on the metal holder is pressed against the sliding surface of the block base accommodating portion, it can be easily moved to a predetermined position in the vertical direction of the block base. The diffraction grating can be positioned and the angle of the diffraction grating can be easily adjusted.

  Furthermore, since the metal holder provided with the diffraction grating is provided with a pair of adjustment pieces, it is easy to apply a force for rotating the diffraction grating when adjusting the angle of the diffraction grating. be able to. For this reason, even if the diffraction grating and the holder are downsized, it is not difficult to improve the efficiency of the assembly work for assembling the diffraction grating to the block base.

  As mentioned above, although this invention was demonstrated based on preferred embodiment shown on drawing, it cannot be overemphasized that this invention is not what is limited to this embodiment. For example, the leaf spring is formed from a metal steel plate, but may be formed from other materials such as plastic as long as it has sufficient strength, elasticity, and heat resistance. Further, the leaf spring is configured to be attached to the opening portion of the block base and press the diffraction grating against the inner wall side of the opening, but may be a clip type that sandwiches the wall portion of the block base.

It is a top view which shows the outline | summary of the optical pick-up apparatus 1 of this invention. It is a perspective view of the optical system block 2 of the optical pick-up apparatus 1 shown in FIG. It is a perspective view of the back surface side of the optical system block 2 shown in FIG. It is a perspective view which shows the state which attached only the 1st diffraction grating 30 (holder 32), the 2nd diffraction grating 40 (holder 42), and the leaf | plate spring 50 to the block base 21 of the optical system block 2 shown in FIG. In the optical system block 2 shown in FIG. 4, the block base 21, the first diffraction grating 30 (holder 32), the second diffraction grating 40 (holder 42), and the leaf spring 50 are separated from the block base 21. FIG. It is a perspective view which shows the holder 32 of the 1st diffraction grating 30 shown in FIG. 5, (a) and (b) are each displayed changing the angle shown in figure. FIG. 6 is a partially enlarged perspective view showing a state where the first diffraction grating portion 30 shown in FIG. 5 is accommodated in the accommodating portion 211 of the block base 21. FIG. 8 is a partially enlarged perspective view showing a state in which a leaf spring 50 is mounted on the block base 21 shown in FIG. 7.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Optical pick-up apparatus 10 Damper base 11 Objective lens 12 Objective lens actuator part 12a Suspension spring 13 Pickup base 13a Sliding part 14 Photo diode 15 1st laser light emitting element 16 2nd laser light emitting element 2 Optical system block 21 Block base 211 212, 216 Housing 211a, 212a Inner wall surface 211b, 212b Sliding surface 22 Collimator lens 23 Sensor lens 24 Front beam splitter 25 Rear beam splitter 26 Coupling lens 30 First diffraction grating 31, 41 Glass substrates 32, 42 Holders 33 and 43 Fixing pieces 34 and 44 Adjustment pieces 35 and 45 Outer side surfaces 36 and 46 Holes 37 and 47 Sliding end surfaces 38 and 48 Inner side surfaces 40 Second diffraction grating 50 Leaf springs 51 and 53 Pressing pieces 52 and 54 Pressing portion 56 Mounting Piece

Claims (9)

At least one laser emitting element;
An objective lens for irradiating an optical disk with laser light emitted from the laser light emitting element;
An objective lens actuator for driving the objective lens in a focus direction and a tracking direction;
At least one photodiode for receiving reflected light from the optical disc;
A number of optical elements arranged between the time when the laser light emitted from the laser light emitting element reaches the objective lens and the time when the reflected light from the optical disc reaches the photodiode from the objective lens;
An optical system block equipped with a plurality of optical elements among the multiple optical elements;
A pickup base provided with the laser light emitting element, the objective lens actuator, the photodiode, and the optical system block, and an optical pickup device comprising:
The optical system block is provided on the pickup base so as to be position-adjustable, and the plurality of optical elements mounted on the optical system block include at least one diffraction grating, and the diffraction grating An optical pickup device, wherein the optical block device is attached to the optical system block in a position-adjustable manner through attachment means that is detachably attached to the system block.   The optical pickup device according to claim 1, wherein the attachment means is a leaf spring that is detachably attached to the optical system block.   The diffraction grating is attached to a thin plate-shaped metal holder having a pair of fixing pieces on both sides, the leaf spring includes at least a pair of pressing pieces, and the diffraction grating is provided on both sides of the holder. The optical pickup device according to claim 2, wherein the fixing piece is attached to the optical system block so that the position thereof can be adjusted by being pressed by the pair of pressing pieces.   The metal holder of the diffraction grating has a sliding end surface, and is rotatably supported by the sliding surface provided in the diffraction grating accommodating portion of the optical system block via the sliding end surface. The optical pickup device according to claim 3.   5. The optical pickup according to claim 1, wherein the optical system block is made of any material selected from a group including zinc, magnesium, aluminum, and an alloy containing two or more thereof. apparatus.   The optical pickup device according to any one of claims 1 to 5, wherein the pickup base is formed of any material selected from a group including zinc, magnesium, aluminum, and an alloy containing two or more thereof. .   The optical pickup device according to claim 5, wherein the optical system block and the pickup base are formed of a metal having the same coefficient of thermal expansion. A laser light emitting element;
An objective lens for irradiating an optical disk with laser light emitted from the laser light emitting element;
An objective lens actuator for driving the objective lens in a focus direction and a tracking direction;
A light receiving element for receiving reflected light from the optical disc;
A number of optical elements arranged between the time when the laser light emitted from the laser light emitting element reaches the objective lens and the time when the reflected light from the optical disk reaches the light receiving element from the objective lens;
An optical system block provided with a plurality of optical elements among the multiple optical elements;
A pickup base on which the laser light emitting element, the objective lens actuator, the light receiving element, and the optical system block are mounted;
The optical system block is provided on the pickup base so that the position thereof can be adjusted, and the optical system block and the pickup pace are formed of a metal material having the same coefficient of thermal expansion. .   The optical pickup device according to claim 8, wherein the metal material is selected from any of magnesium, zinc, aluminum, and alloys thereof.

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