JP2008293551A - Optical pickup - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical pickup provided with an objective lens for suppressing scratch of an optical disk and defects of the objective lens by suppressing contact between the objective lens and the optical disk even when the optical disk and the optical disk are approached abnormally. <P>SOLUTION: The optical pickup A has the objective lens 36, an objective lens holder 24 holding the objective lens 36, and buffer members 27 provided at an upper plane of the objective lens holder 24, wherein concave grooves 245 are formed at the upper plane of the lens holder 24, each of the buffer members 27 is a chevron member having a pair of oblique parts 271 formed in a pillar shape and coupling parts 272 of a pillar shape coupling end parts of the oblique parts 271, a tip side of the oblique part 271 is inserted into the concave groove 245, while the coupling parts 272 are fixed so as to project from the upper plane of the objective lens 36 and the objective lens holder 24. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

The present invention relates to an optical pickup that can irradiate an optical disk with laser light for information reproduction or recording and suppress contact between the objective lens and / or the objective lens holder and the optical disk.

  2. Description of the Related Art An optical disk apparatus that records or reproduces data by irradiating light to an optical disk such as a CD or DVD that is a recording medium includes an optical pickup that irradiates the optical disk with laser light. The optical pickup includes a laser light source and an objective lens that converges the laser light emitted from the laser light source.

  The optical pickup irradiates a track formed on the recording surface of the optical disk in a spiral or concentric manner with a laser spot obtained by converging the laser light emitted from the laser light source with the objective lens, and performs recording or reproduction. Is going.

  In the optical pickup, in order to accurately irradiate the track with the laser spot, the objective lens changes the optical axis direction (focus direction), the radial direction of the optical disc (tracking direction), and the direction of changing the angle of the optical axis (tilt). It is attached to an objective lens holder that can move in the direction).

  The objective lens holder includes a lens driving mechanism that can move the objective lens holder in the focus direction, the tracking direction, and the tilt direction by using a magnet and a coil. By driving the lens driving mechanism, the focal point of the laser spot can be made coincident with the recording surface of the optical disc, and the laser spot can accurately follow the track of the optical disc.

  In recent years, a Blu-ray Disc (BD) having a larger storage capacity than DVD has been announced. BD media has the same diameter as CD media and DVD media, and has a storage capacity about five times that of DVD. That is, the recording density of BD is higher than that of DVD (the track width on the recording surface is narrow). For this purpose, the size of the laser spot needs to be reduced.

  In the optical disc apparatus, the minimum value of the diameter of the laser spot is determined by the wavelength of the laser beam and the numerical aperture (NA) of the objective lens. Generally, the shorter the wavelength and the larger the NA, the laser spot. The minimum value of the diameter becomes smaller. For example, the laser light employed in the optical pickup for CD is an infrared laser having a wavelength of about 780 nm, and the NA of the objective lens is about 0.45. Further, a DVD optical pickup employs a laser light source that emits a red laser having a wavelength of about 650 nm and an objective lens having an NA of about 0.6.

  In contrast, an optical pickup used for BD recording / reproduction uses a laser light source that emits a blue laser having a wavelength of about 405 nm and an objective lens having an NA of about 0.85.

  In general, the working distance, which is the distance between the objective lens and the optical disc, decreases as the NA increases. It is about 1.2 mm for an optical pickup for recording / reproducing a CD, and about 0.6 mm for an optical pickup for recording / reproducing a DVD. On the other hand, the optical pickup for recording / reproducing BD is about 0.2 mm, which is very small.

  When unexpected external force such as impact applied to the optical disk device or vibration of the drive system, or troubles such as control disturbance occur, the objective lens and the optical disk may approach abnormally and contact or collide with each other. There is sex. If the objective lens and the optical disk come into contact with each other and the objective lens is scratched or damaged, the optical pickup cannot correctly focus the laser spot, and can accurately perform recording / reproduction. become unable. Also, if the optical disk is damaged, the optical disk may not be able to be reproduced, and valuable data may be damaged.

  Therefore, in the conventional optical pickup, when the objective lens is abnormally close to the optical disk in the vicinity of the objective lens, protection is provided to prevent the objective lens from contacting or colliding with the optical disk. A member is attached. The protective member is formed of a material having sufficient wear properties, and the optical disk is not damaged even when it comes into contact with the optical disk.

The protective member is disposed so as to be close to a part of the objective lens holder of the optical pickup where the objective lens is attached and to face the objective lens with the objective lens interposed therebetween. As the protective member, the protective member is separately manufactured and attached and fixed to the optical pickup (Japanese Patent Laid-Open No. 2006-155825), or the protective member is formed integrally with the objective lens holder (Japanese Patent Laid-Open No. 2007). No. 18863), and a coating with high wear resistance.
JP 2006-155825 A JP 2007-18632 A

  As described above, in the case of an optical pickup that reproduces the BD, the working distance is very narrow. Like the optical pickups described in Japanese Patent Application Laid-Open Nos. 2006-155825 and 2007-18235, when the protective member having a predetermined shape and size is used for an optical pickup for BD, it is possible to It is difficult to accurately set the distance between the protective member and the optical disc at the time of design when variations or mounting errors occur during assembly.

  Therefore, when the optical disk and the protective member come into contact with each other with slight fluctuations (as assumed at the time of driving), or when the objective lens holder abnormally approaches the optical disk, it comes into contact with the protective member. Before, there is a possibility of contact with the objective lens and / or the objective lens holder.

  When the objective lens holder is coated with high wear and this coating film is used as a protective member, the distance between the protective member and the optical disk can be adjusted by the film thickness of the coating. However, in order to apply the coating, a pretreatment such as masking is required, which takes time and effort. Further, in order to increase the thickness of the coating, it is necessary to repeat the coating a plurality of times, which takes time and effort. In addition, since the coating itself is expensive, the cost for manufacturing the optical pickup increases.

  Therefore, the present invention has been made in view of the above-described problems. When the optical pickup is abnormally close to the optical disk with a simple configuration, the optical disk and the objective lens and / or the objective lens holder contact / collision. It is an object of the present invention to provide an optical pickup capable of suppressing the occurrence of this.

  To achieve the above object, the present invention includes an objective lens disposed opposite to an optical disc, an objective lens holder on which the objective lens is held on an upper surface, and a buffer member provided on the upper surface of the objective lens holder. And a concave groove having at least two rectangular bottom surfaces around the objective lens is formed on the upper surface of the objective lens holder, and the buffer member is a pair of columnar shapes. And a columnar connecting portion that connects the end portions and connects the end portions to each other, and at least the connecting portion includes the objective lens and the objective lens holder. The friction coefficient is smaller than that of the surface of the optical disc, and the buffer member is an end portion that is not connected to the connecting portion of the pair of skew portions. With part is inserted into the groove, wherein the connecting portion is fixed to protrude so as to approach to the objective lens and the optical disc from the upper surface of the objective lens holder.

  According to this configuration, even when the objective lens abnormally approaches the optical disc, the coupling portion of the buffer member is connected to the optical disc before the optical disc and the objective lens or the objective lens holder come into contact / collision. Contact with.

  As a result, the optical disk does not contact the objective lens or the objective lens holder, so that the objective lens is damaged or damaged, and the laser beam cannot be slid accurately, or the objective lens is displaced and the laser is displaced. It is possible to prevent the recording / reproducing from becoming unstable or impossible because the optical axis of the light is shifted.

  In addition, since the connecting portion has a smaller coefficient of friction than the objective lens and the objective lens holder and is formed to be more easily worn than the optical disc, the optical disc contacts the objective lens or the objective lens holder. In comparison, the optical disk is less likely to be damaged.

  As a result, it is possible to prevent the optical disk from being unusable and to prevent the occurrence of a problem that the data recorded on the optical disk cannot be taken out.

  The said structure WHEREIN: The said buffer member is formed so that deformation | transformation is possible so that the distance between the front-end | tip parts of a pair of said skew feeding part may be expanded, and the said buffer member is deform | transformed so that the distance between the said front-end | tip parts may be expanded. It may be inserted and fixed in the concave groove.

  According to this configuration, by increasing the distance between the ends of the pair of skew portions, the distance between the line connecting the ends and the connecting portion can be adjusted. Thereby, it is possible to make the protrusion amount which protrudes from the objective lens and the objective lens holder of the connecting portion appropriate.

  In the above configuration, the front end portion of the skewed portion may be in contact with the bottom surface of the concave groove, and the front end portion and the bottom surface may be bonded and fixed. , A projecting portion standing from the center in the longitudinal direction is formed, and the buffer member has a portion between the tip portion of the pair of skewed portions and the connecting portion fixed to the projecting portion It may be.

  The said structure WHEREIN: The said buffer member may be formed so that at least one of said pair of skew part or the said connection part can be elastically deformed.

  According to this configuration, the shape of the buffer member can be confirmed while being deformed, so even if it is deformed too much, it returns to its original state, so that the connecting portion is prevented from protruding from the objective lens or the objective lens holder. Is possible. In addition, since the impact force when contacting or colliding with the optical disk can be relaxed by elastic deformation, it is possible to prevent the optical disk from being damaged.

  In the above-described configuration, the buffer member is deformed by urging the connecting portion, and a laser spot formed by condensing the protruding amount that the connecting portion protrudes from the objective lens by the objective lens; It may be adjusted so as to be shorter than the distance to the objective lens.

  According to this configuration, even when there are individual differences due to manufacturing errors, assembly errors, aberrations, and the like of the optical components including the objective lens, it is possible to optimize the protruding amount of the connecting portion. . This provides an optical pickup that can effectively cause defects such as scratches and breakage in the objective lens and / or the optical disc without increasing the processing accuracy required for the buffer member. Is possible. Further, since it is not necessary to increase the processing accuracy, it is possible to keep the manufacturing cost low.

  According to the present invention, there is provided an optical pickup capable of suppressing contact / collision between the optical disc and the objective lens and / or objective lens holder when the optical pickup abnormally approaches the optical disc with a simple configuration. can do.

  Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a layout view showing the configuration of an example of an optical pickup according to the present invention. An optical pickup A shown in FIG. 1 includes a main body 1 and an actuator 2 that drives an objective lens. The optical pickup A shown in FIG. 1 includes an optical system 3 for recording / reproducing BD. In the optical pickup shown in FIG. 1, for the sake of convenience, the optical path of the blue laser is indicated by a solid line.

  The optical system 3 includes at least a blue laser light source 31, a polarization beam splitter 32, a collimator lens 33, a rising mirror 34, a quarter wavelength plate 35, an objective lens 36, a sensor lens 37, and a light receiving element Pd. And.

  The blue laser light source 31 emits blue laser light having a wavelength of about 405 nm, and is used for recording / reproduction of BD media. The polarization beam splitter 32 is a prism that transmits or reflects depending on the polarization direction of the incident laser light. In the present invention, the laser light emitted from the blue laser light source 31 and incident on the polarization beam splitter 32 is transmitted, and the laser light reflected on the recording surface of the BD medium is reflected by the polarization beam splitter 32.

  The collimator lens 33 converts laser light, which is diffused light emitted from the blue laser light source 31, which is a point light source, into parallel light. The laser light emitted from the collimator lens 33 is reflected by the rising mirror 34 in the orthogonal direction. As a result, the optical path of the laser light is changed in a direction orthogonal to the recording layer of the BD medium.

  The quarter-wave plate 35 generates a quarter-wave phase difference in incident light, and can convert linearly polarized light into circularly polarized light and circularly polarized light into linearly polarized light. The objective lens 36 can converge the blue laser beam and irradiate the recording surface of the BD medium as a laser spot.

  The laser beam reflected by the recording surface of the BD medium is incident on the quarter wavelength plate 35 again. At this time, the reflected laser light is converted from circularly polarized light to linearly polarized light. The polarization direction of the laser light converted into the linearly polarized light is orthogonal to the polarization direction of the laser light emitted from the blue laser light source. As a result, the laser beam is reflected by the polarization beam splitter 32 without being transmitted, and enters the light receiving element Pd via the sensor lens 37. In the light receiving element Pd, the incident laser light is converted into an electric signal and used as an output signal for recording / reproduction.

  Among the optical members described above, the objective lens 36 is disposed on the actuator 2. The actuator 2 is attached to the main body 1.

  2 is a plan view of an example of an actuator provided in the optical pickup according to the present invention, FIG. 3 is a front view of the actuator shown in FIG. 2, and FIG. 4 is an objective lens holder used in the actuator shown in FIG. FIG. 5 is a cross-sectional view of the objective lens holder provided in the optical pickup according to the present invention. The actuator 2 includes an actuator base 21, a permanent magnet 22, a support member 23, an objective lens holder 24 that holds an objective lens 36, a power board 25, a wire spring 26, and a buffer member 27. In the figure, Ta is the tangential direction (circumferential direction) of the BD media, and Ra is the radial direction (radial direction).

  The actuator base 21 is formed by punching or cutting a metal plate. The actuator base 21 includes a through hole 211 through which the blue laser light passes, and a magnet holding portion 212 that holds the permanent magnet 22 and acts as a back yoke. The permanent magnet 22 causes a magnetic field to act on the objective lens holder 24, and although not limited thereto, a neodymium magnet is employed.

  The support member 23 is made of resin and is firmly fixed to the actuator base 21 using bolts (not shown). Moreover, it is not limited to a volt | bolt, The thing fixed so that it may not drop from the actuator base 21, such as fitting, welding, adhesion | attachment, can be employ | adopted widely.

  Here, a flexible printed circuit (FPC) having flexibility is adopted as the power substrate 25 and is bonded so as to cover a part of the support member 23. The power board 25 is not limited to the FPC, and those that can be stably attached to the support member 23 can be widely used. The power board 25 is provided with a terminal portion 251 for supplying power.

  The objective lens holder 24 will be described with reference to the drawings. As shown in FIGS. 3 and 4, the objective lens holder 24 penetrates from the lower surface to the upper surface, and the objective lens mounting hole 241 in which the objective lens 36 is mounted on the upper surface end side, and the objective lens holder 24 in the optical axis direction. A focus coil 242 for sliding, a tracking coil 243 for sliding the objective lens holder 24 in the radial direction of the optical disk, and a connection terminal 244 for supplying power to the focus coil 242 and the tracking coil 243 ing.

  The objective lens holder 24 is supported by the support member 23 via the wire spring 26 so that the bottom portion does not contact the actuator base 21. The wire spring 26 is an elastic member having conductivity, and is attached so as to come into contact with the connection terminal 244 of the objective lens holder 24. Further, it is in contact with the terminal portion 251 of the power board 25 attached to the support member 23. In this way, the terminal portion 251 and the connection terminal 244 are electrically connected via the wire spring 26, and power is supplied from the power board 25 to the focus coil 242 and the tracking coil 243 via the wire spring 26. .

  The objective lens 36 has a large numerical aperture (NA) (NA = 0.85). Accordingly, the distance (working distance) from the objective lens 36 to the optical disk is shorter than that of the optical pickup for CD and DVD, and the objective lens 36 is attached so as to protrude from the upper surface of the objective lens holder 24. 36 and the optical disk (BD) are easily in contact with each other. Therefore, the buffer member 27 is attached to the upper surface of the objective lens holder 24 in order to suppress direct contact between the objective lens 36 and the optical disc (BD).

  In the objective lens holder 24, a pair of concave grooves 245 having a rectangular cross section are formed at positions facing each other with the lens mounting hole 241 therebetween, and the buffer member 27 is inserted into each of the pair of concave grooves 245, Has been placed. As shown in FIG. 5, the concave grooves 245 are not limited to this, but are formed side by side in the tangential (Ta) direction of the optical disk here.

  The buffer member 27 is a resin (e.g., polyacetal, tetrafluoroethylene, super High-molecular-weight polyethylene and the like) and sheet-like products. As shown in FIG. 5, the buffer member 27 includes a pair of skewed portions 271 that are inclined so as to tilt toward each other, and a connecting portion 272 that couples the pair of skewed portions 271 together. As shown in FIG. 6, the skew portion 271 is a plate-like member having the same length and shape. The inclined portion 271 itself can be elastically deformed. Further, the connecting portion 272 can also be elastically deformed.

  A procedure for attaching the buffer member 27 shown in FIG. 5 to the objective lens holder 24 will be described below. FIG. 6 is a sectional view when the buffer member is attached to the concave groove. First, the concave groove 245 of the objective lens holder 24 is filled (applied) with an ultraviolet curable adhesive so that the tip of the skewed portion 271 of the buffer member 27 comes into contact with the bottom of the concave groove 245 from above. To place. As shown in FIGS. 5 and 6, the buffer member 27 is disposed in the concave groove 245 so that the skew portion 271 faces downward. At this time, the connecting portion 272 protrudes above the objective lens 36. In addition, as shown in FIG. 2, the length of the cushioning member 27 in the end-hand direction is slightly smaller than the length of the concave groove 245 in the short-side direction. It is arranged so that it hardly moves in the short direction.

  In this state, by urging the connecting portion 272 of the buffer member 27 in the direction of the objective lens 24, the end of the skewed portion 271 is opened by the deformation of the skewed portion 271 and the elastic deformation of the connecting portion 272, and the connecting portion The protrusion amount protruding from the objective lens 36 of 272 is adjusted. This protruding amount is formed to be smaller than the working distance of the optical pickup A. In addition, adjustment is made to maintain a predetermined distance so that the connecting portion 272 does not come into contact with or collide with the optical disc during focus adjustment of the optical pickup A. When this height adjustment is performed, laser light is irradiated from the objective lens 36, the laser spot is observed, and the protrusion amount is determined.

  In a state where the force is applied to the connecting portion 272 and the buffer member 27 is deformed, the ultraviolet curable adhesive filled in the concave groove 245 is irradiated with ultraviolet rays to cure the adhesive, and the buffer member 27 is recessed. It is fixed to the groove 245.

  As described above, the height of the buffer member 27 protruding from the objective lens holder 24 is adjusted while measuring the laser beam. Therefore, errors during manufacture of each member attached to the optical pickup A, errors during assembly, and aberrations The buffer member 27 is not in contact with the optical disk when the optical pickup A is normally operated, and the objective lens 36 is abnormally close to the optical disk A when the optical pickup A is normally operated. It is possible to prevent the optical disk 27 and the objective lens 36 from contacting and colliding with each other.

  Another example of the optical pickup according to the present invention will be described with reference to the drawings. FIG. 7 is a cross-sectional view of the objective lens holder provided in the optical pickup according to the present invention, and FIG. 8 is a cross-sectional view of the objective lens holder when the buffer member is attached. The objective lens holder shown in FIGS. 7 and 8 has the same shape as the objective lens holder 24 shown in FIGS. 5 and 6 except that the shape of the concave groove and the buffer member is different. The objective lens holder 24b can be attached to the optical pickup A in place of the objective lens holder 24.

  A concave groove 246 is formed in the objective lens holder 24b shown in FIG. The concave groove 246 has a rectangular parallelepiped protruding portion 247 protruding from the center of the bottom surface. The buffer member 28 is formed in a V-shape like the buffer member 27, and has a pair of skewed portions 281 and a connecting portion 282 that couples the pair of skewed portions 281. .

  As shown in FIG. 8, the damp groove 246 is filled with an ultraviolet curable adhesive, and the buffer member 28 is arranged so that both end portions of the upper surface of the protruding portion 247 and the inclined portion 281 are in contact with each other. At this time, the connecting portion 282 protrudes from the objective lens 36.

  In this state, by urging the connecting portion 282 of the buffer member 28 in the optical axis direction of the objective lens 36, the end portion of the inclined portion 281 is opened by elastic deformation of the inclined portion 281 and the connecting portion 282, and the connecting portion 282 is connected. The amount of protrusion of the portion 282 protruding from the objective lens 36 is adjusted. This protruding amount is formed to be smaller than the working distance of the optical pickup. Further, when the focus of the optical pickup is normally adjusted, the connecting portion 282 is adjusted so as to keep a predetermined distance so as not to contact the optical disc. When this height adjustment is performed, laser light is irradiated from the objective lens 36, the laser spot is observed, and the protrusion amount is determined.

  In a state where the force is applied to the connecting portion 282 and the buffer member 28 is deformed, the ultraviolet curable adhesive filled in the concave groove 246 is irradiated with ultraviolet rays to cure the adhesive, and the buffer member 28 is recessed. It is fixed to the groove 246. Moreover, after adjusting the height of the buffer member 28, the buffer member 28 and the protrusion part 281 may be bonded together.

  As described above, the height of the buffer member protruding from the objective lens holder is adjusted while measuring the laser beam, so that it depends on errors in manufacturing each member attached to the optical pickup, errors in assembly, aberrations, etc. The buffer member does not come into contact with the optical disc when the optical pickup is normally operated, and the buffer member comes into contact with the optical disc when the objective lens abnormally approaches the optical disc. It is possible to suppress contact and collision with the objective lens.

  Since the buffer member is more slidable than the objective lens and the objective lens holder, the objective lens can be prevented from being damaged or displaced, and the optical pickup can be operated stably. Further, since the optical disc is prevented from coming into contact with a hard objective lens or objective lens holder, the optical disc can be prevented from being damaged. Thereby, it is possible to prevent the data recorded on the optical disk from being unusable. In addition, since the slanted portion and the connecting portion of the buffer member are formed so as to be elastically deformable, they can be elastically deformed when contacted or collided, and the impact force at the time of contacting or colliding can be reduced. Accordingly, it is possible to suppress damage to the optical disk and the objective lens.

  In each of the above-described embodiments, the optical pickup using BD for recording / reproducing is described as an example. However, the present invention is not limited to this, and the optical pickup using CD and DVD for recording / reproducing is also used. Is possible. Further, it can also be employed in an optical pickup provided with both an objective lens for CD and / or DVD and an objective lens for BD.

  Further, in each of the above-described embodiments, for the sake of convenience, description will be given by taking as an example a case where two buffer members are provided in parallel with the tangential direction with the objective lens holder interposed therebetween (in other words, extending in the radial direction). However, the present invention is not limited to this, and it may be arranged at a predetermined angle in the radial direction, tangential direction, or radial direction, or not parallel. Further, more than two buffer members may be provided.

  Further, in each of the above-described embodiments, the buffer member 27 (28) is applied to the objective lens that is formed so as to protrude to the top (to be close to the optical disc), but the present invention is not limited thereto. Instead, the present invention can also be applied to a case where a part of the objective lens holder is formed so as to protrude from the objective lens. When the objective lens (objective lens holder) abnormally approaches the optical disc, a wide variety of optical discs can be used so that the optical disc contacts the buffer member before contacting the objective lens (objective lens holder).

  Further, in the above embodiment, the case where both the slanting portion and the connecting portion of the buffer member are formed so as to be elastically deformable is described as an example. However, the present invention is not limited to this, and at least one of them is elastically deformed. If possible. By pressing the connecting portion, it is possible to widely adopt a device that can adjust the protruding amount of the connecting portion protruding from the objective lens or the objective lens holder.

  As mentioned above, although embodiment of invention was described concretely, this invention is not limited to the said embodiment, A various change is possible in the range which does not deviate from the summary. A plurality of features described in the above embodiments may be provided.

  The present invention can be applied to an optical pickup used in an optical disc apparatus using an optical disc as a recording medium.

FIG. 1 is a layout view showing the configuration of an example of an optical pickup according to the present invention. It is a top view of an example of the actuator with which the optical pick-up concerning this invention was equipped. FIG. 3 is a front view of the actuator shown in FIG. 2. It is an expansion perspective view of the objective lens holder used for the actuator shown in FIG. It is sectional drawing of an example of the objective-lens holder shown in FIG. It is sectional drawing before attaching a buffer member to a ditch | groove in the objective-lens holder shown in FIG. It is sectional drawing of the objective-lens holder with which the other example of the optical pick-up concerning this invention was equipped. It is sectional drawing of the objective lens holder before attaching a buffer member to the objective lens holder shown in FIG.

Explanation of symbols

A Optical pickup 1 Main body 2 Actuator 21 Actuator base 22 Permanent magnet 23 Support member 24 Objective lens holder 241 Objective lens mounting hole 242 Focus coil 243 Tracking coil 244 Connection terminal 245 Concave groove 246 Concave groove 247 Projection part 25 Power board 26 Wire spring 27 Buffer member 271 Skew section 272 Connecting section 3 Optical system 31 Laser light source 32 Polarizing beam splitter 33 Collimator lens 34 Rising mirror 35 1/4 wavelength plate 36 Objective lens 37 Sensor lens

Claims (6)

An objective lens disposed opposite the optical disc;
An objective lens holder with the objective lens held on the upper surface;
An optical pickup having a buffer member provided on the upper surface of the objective lens holder,
A concave groove having at least two rectangular bottom surfaces is formed around the objective lens on the upper surface of the objective lens holder,
The shock-absorbing member is a mountain-shaped member having a pair of skewed portions formed in a columnar shape, and a columnar coupling portion that connects the end portions of the skewed portion and connects the ends to each other. The connecting portion has a smaller coefficient of friction than the objective lens and the objective lens holder, and is formed to be more easily worn than the surface of the optical disc.
The buffer member has a tip portion that is an end portion that is not connected to the connecting portion of the pair of skew portions, and the connecting portion is inserted from the upper surface of the objective lens and the objective lens holder. An optical pickup characterized in that it protrudes and is fixed so as to approach the optical disc. The buffer member is formed to be deformable so that the distance between the tip portions of the pair of skew portions is increased,
The optical pickup according to claim 1, wherein the buffer member is deformed so as to increase a distance between the tip portions, and is inserted and fixed in the concave groove.   The optical pickup according to claim 1 or 2, wherein a tip portion of the skew portion is in contact with a bottom surface of the concave groove, and the tip portion and the bottom surface are bonded and fixed. On the bottom surface of the concave groove, a protruding portion is formed standing from the vicinity of the center in the longitudinal direction,
3. The optical pickup according to claim 1, wherein a portion of the buffer member between a tip portion of the pair of skew portions and the connecting portion is fixed to the protruding portion.   5. The optical pickup according to claim 1, wherein at least one of the pair of skew portions or the connecting portion is formed to be elastically deformable in the buffer member. The buffer member is deformed when the connecting portion is urged,
When irradiating the optical disk with laser light from the objective lens, the amount of protrusion protruding from the upper surface of the objective lens and the objective lens holder of the connecting portion is the amount of the optical disk and the objective lens or the upper surface of the objective lens holder. 6. The optical pickup according to claim 5, wherein the optical pickup is adjusted to be shorter than a shorter one of the distances.

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