JP2010140522A - Objective lens unit, optical pickup, electronic equipment carrying the same, and method of manufacturing objective lens unit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an objective lens unit which can easily adjust a posture of an objective. <P>SOLUTION: The objective lens unit includes: a plurality of objective lenses with different numerical apertures; a main part in which the objective lenses are carried adjacently; an objective fixing frame which holds at least one objective lens and is mounted in a posture controllable way to the main part. In the main part, at least one adjustment aperture in which a portion of objective lens fixed frame mounted to the main part is exposed outside to enable posture adjustment from outside is formed, and an operation section which is exposed outside through the adjustment aperture is formed in the objective lens fixing frame. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an objective lens unit, an optical pickup, an electronic apparatus equipped with the same, and a method for manufacturing the objective lens unit.

  The prior art related to this invention includes a main body provided with an actuator and two objective lenses mounted on the main body, and the main body adjusts the mounting posture of the objective lens with respect to the main body when the objective lens is mounted. There is known an objective lens unit of an optical pickup in which a tilted seating surface to be formed is formed on a mounting portion of the objective lens (see, for example, Patent Documents 1 and 2).

JP 2005-174485 A JP 2006-19001 A

  In recent years, information recording / reproducing apparatuses based on the Blu-ray method have been rapidly spread. In the Blu-ray method, a blue-violet laser having a relatively short wavelength of 405 nm is used as a light source, and the laser light is finely narrowed by an objective lens having a large numerical aperture to form a minute spot. ), It is possible to write and read more information than an optical disc such as a conventional DVD (digital versatile disc) or CD (compact disc).

On the other hand, since DVDs and CDs have been widely used, there are many users who store recorded DVDs and CDs, and Blu-ray information recording / reproducing apparatuses are also required to be compatible with DVDs and CDs.
DVD uses a red laser with a wavelength of 660 nm as a light source, and CD uses an infrared laser with a wavelength of 780 nm as a light source. And the spot diameter which irradiates the recording surface of an optical disk is larger than the above-mentioned Blu-ray system.
For this reason, in DVD and CD, the numerical aperture of the objective lens for narrowing down the laser beam is generally smaller than that in the Blu-ray system.

  Due to the difference between the Blu-ray system and the DVD / CD, in order to ensure compatibility with the DVD and CD in the Blu-ray system information recording / reproducing apparatus, the reflected light is read by irradiating the recording surface of the optical disk with laser light. It is necessary to mount a plurality of light sources and a plurality of objective lenses corresponding to them on the optical pickup.

The optical pickup includes an objective lens unit as a mount on which the objective lens is mounted. The optical pickup has a track groove (a minute bit string) corresponding to a change in the position of the recording surface such as surface blurring and eccentricity caused by the rotation of the optical disk. The objective lens unit is equipped with an electromagnetic actuator that displaces the mounted objective lens so that it can be appropriately irradiated.
Specifically, a focus error signal and a tracking error signal are detected from the reflected light of the optical disk, and information is read while always performing focus adjustment and tracking adjustment of the laser light.
As described above, in order to support both the Blu-ray system and the DVD / CD, at least two objective lenses having different numerical apertures must be mounted on the objective lens unit.

For example, when an objective lens unit is equipped with a Blu-ray objective lens and a DVD / CD objective lens, as described above, the Blu-ray objective lens has a larger numerical aperture than the DVD / CD objective lens. Therefore, higher mounting accuracy is required than the objective lens for DVD / CD.
For this reason, in the objective lens mounting process, the objective lens for Blu-ray system is attached to the objective lens unit with priority adjustment, and then the objective lens for Blu-ray system is used for DVD / CD as a reference. Generally, a method of simply aligning and mounting an objective lens is taken.

Specifically, after mounting an objective lens for the Blu-ray system, using an actuator mounted on the objective lens unit, the coma aberration measured by the focal aberration adjuster or actually irradiating the optical disk The posture is adjusted so that the mounting posture becomes the best by the signal output of the optical pickup based on the jitter value and the error rate.
After that, the DVD / CD objective lens is simply aligned and mounted and fixed based on the mounting orientation of the Blu-ray objective lens mounted and adjusted in advance.

However, with such a mounting method, the mounting posture of the objective lens for DVD / CD basically depends on the component accuracy of the objective lens unit, and the mounting accuracy must be lower than that of the objective lens for the Blu-ray system. I don't get it.
For this reason, it is difficult for the objective lens for DVD / CD to exhibit the desired performance, and the yield of the optical pickup is reduced.

  In the above-described Patent Documents 1 and 2, since an inclined seating surface is formed at the mounting position of the objective lens, it is considered that the posture of one objective lens can be adjusted independently of the other objective lens. It is done. And if this feature is used, the objective lens for Blu-ray system can be adjusted by the actuator with high accuracy, and then the objective lens for DVD / CD can be adjusted and attached separately from the objective lens for Blu-ray system. It is considered possible.

However, when the DVD / CD objective lens is mounted, the actuator of the objective lens unit is already optimized with respect to the objective lens for the Blu-ray system.
For this reason, the posture of the DVD / CD objective lens cannot be adjusted by the actuator in the same manner as the objective lens for the Blu-ray system, and the posture of the DVD / CD objective lens must be adjusted by means other than the actuator. .

  Both the Blu-ray objective lens and the DVD / CD objective lens are very small lenses with a diameter of about 3 to 5 mm. However, there are problems in terms of workability and production efficiency.

  The present invention has been made in view of the above circumstances, and provides an objective lens unit in which the orientation of the objective lens can be easily adjusted and an optical pickup equipped with the objective lens unit.

  The present invention provides a plurality of objective lenses having different numerical apertures, a main body on which the objective lenses are mounted adjacent to each other, and an objective lens fixing that holds at least one objective lens and is mounted on the main body so that the posture can be adjusted. And at least one adjustment hole is formed in the main body so that a part of the objective lens fixing frame mounted on the main body is exposed to the outside so that the posture adjustment from the outside is possible. The objective lens unit is provided with an action portion exposed to the outside through the adjustment hole.

According to the present invention, the main body on which the plurality of objective lenses are mounted has at least one adjustment hole that allows a part of the objective lens fixing frame attached to the main body to be exposed to the outside to adjust the posture from the outside. Since the action part exposed to the outside is formed in the objective lens fixing frame through the adjustment hole, the objective lens can be fixed by operating the action part of the objective lens fixing frame using a jig or the like from the outside. The posture of the frame can be adjusted.
Therefore, the attitude of the objective lens held by the objective lens fixing frame can be easily and quickly adjusted from the outside, and the production efficiency and the yield can be improved.

  An objective lens unit according to the present invention is mounted with a plurality of objective lenses having different numerical apertures, a main body on which the objective lenses are mounted adjacent to each other, and holding at least one objective lens so that the posture can be adjusted with respect to the main body. An objective lens fixing frame, and at least one adjustment hole is formed in the main body so that a part of the objective lens fixing frame attached to the main body is exposed to the outside and the posture adjustment from the outside is possible. The objective lens fixing frame is formed with an action portion exposed to the outside through the adjustment hole.

In the objective lens unit according to the present invention, as described above, the plurality of objective lenses may be attached to the main body after at least one objective lens is held by the objective lens fixing frame.
Therefore, all the objective lenses may be mounted on the main body after being held by the objective lens fixing frame. In this case, the number of objective lens fixing frames corresponding to the plurality of objective lenses is provided.

The main body only needs to be equipped with a plurality of objective lenses and at least part of which has an adjustment hole for exposing a part of the objective lens fixing frame to the outside. is not. The main body may include, for example, an electromagnetic actuator that adjusts the posture of the mounted objective lens.
It is sufficient that at least one adjustment hole is provided for one objective lens fixing frame, and a plurality of adjustment holes may be provided for one objective lens fixing frame.

The objective lens fixing frame is a frame-shaped member that surrounds and holds the periphery of the objective lens, and may be any member as long as an action part that is exposed to the outside through the adjustment hole of the main body is formed. The configuration is not particularly limited.
Here, the action part means a part that is exposed to the outside from the adjustment hole and is operated by a jig or the like to transmit a force that moves the posture of the objective lens fixing frame. It is not limited.
The action part should just be formed in at least one part of the objective lens fixed frame. Therefore, the action part may be formed at a plurality of locations of the objective lens fixing frame, or may be formed over the entire objective lens fixing frame.

In the objective lens unit according to the present invention, the main body has a circular seating surface formed by a concavely curved surface in a portion where the objective lens fixing frame is mounted, and the objective lens fixing frame is a circular ring shape, You may have the outer peripheral surface formed with the curved surface which protruded convexly so that it could slide on a seat surface.
According to this configuration, the posture can be adjusted by smoothly sliding the objective lens fixing frame on the seating surface of the main body, and the posture of the objective lens can be adjusted with high accuracy.

In the above-described configuration, in which the main body has a seat surface formed of a curved surface, and the circular ring-shaped objective lens fixing frame can slide on the seat surface, the action portion of the objective lens fixing frame is the outer peripheral surface of the objective lens fixing frame. The adjustment hole of the main body may be provided so as to penetrate the seating surface.
According to such a configuration, since the action portion is provided in the portion having the largest diameter of the objective lens fixing frame, the posture movement amount (movement angle) of the objective lens fixing frame with respect to the operation amount (movement distance) of the action portion is slight. It becomes easy to perform fine posture adjustment. As a result, the posture adjustment of the objective lens can be performed with higher accuracy.

In the above configuration in which the action portion of the objective lens fixing frame is provided on the outer peripheral surface of the objective lens fixing frame and the adjustment hole of the main body is provided so as to penetrate the seating surface, the action portion of the objective lens fixing frame is the same as that of the objective lens fixing frame. You may consist of the hole or groove | channel formed in the outer peripheral surface.
According to such a configuration, the posture of the objective lens fixing frame can be adjusted by operating the hole or groove forming the action portion from the outside, and the posture adjustment of the objective lens is facilitated.
In addition, even if the operation part is operated using a dedicated jig or the like, the structure of the jig for operating the operation part is simple because the action part is formed by a hole or a groove. This simplifies the manufacturing process and increases the efficiency of manufacturing.

In the objective lens unit according to the present invention, it is preferable that the objective lens fixing frame is fixed to the main body in the posture after the posture adjustment.
This is because the adjusted posture of the objective lens can be maintained by fixing the objective lens fixing frame to the main body in the posture after the posture adjustment.
For fixing the objective lens fixing frame after posture adjustment, for example, a resin adhesive such as an ultraviolet curable adhesive, a thermosetting adhesive, or a cyanoacrylate adhesive can be used.

In the objective lens unit according to the present invention, the plurality of objective lenses may include a first objective lens and a second objective lens, and the first objective lens may have a larger numerical aperture than the second objective lens.
According to such a configuration, it is possible to provide two optical systems by mounting two objective lenses having different numerical apertures so that, for example, it can correspond to different types of optical disks such as a Blu-ray system, a DVD, and a CD. Become.

A plurality of objective lenses are composed of a first objective lens and a second objective lens, and the first and second objectives are mounted in the above-described configuration in which the numerical aperture of the first objective lens is larger than the numerical aperture of the second objective lens. An actuator for adjusting the posture of the objective lens may be provided, the objective lens fixing frame may hold the second objective lens, and the first objective lens may be directly fixed to the main body.
According to such a configuration, the first objective lens, which has a larger numerical aperture than the second objective lens and requires a higher mounting accuracy than the second objective lens, is accurately positioned by using the actuator provided in the main body. For the second objective lens, which is adjusted and mounted and the mounting accuracy is not required as much as the first objective lens, the operation part of the objective lens fixing frame is operated from the outside by using a jig or the like, and the objective lens fixing frame with respect to the main body is mounted. By adjusting the posture, the first and second objective lenses can be mounted on the main body in a good posture.

In the above-described configuration in which the objective lens fixing frame holds the second objective lens and the first objective lens is directly fixed to the main body, the action portion of the objective lens fixing frame and the adjustment hole of the main body are the main point of the first objective lens. You may provide so that it may be located on the axis line which passes along the principal point of a 2nd objective lens.
According to such a configuration, the posture can be adjusted by rotating the second objective lens around the principal point (the optical center of the lens) of the second objective lens, and the principal point is maintained at one point before and after the posture adjustment. Therefore, it is easy to adjust the posture, and the production efficiency can be further improved.

In the above-described configuration in which the objective lens fixing frame holds the second objective lens and the first objective lens is directly fixed to the main body, the action portion of the objective lens fixing frame and the adjustment hole of the main body are the main point of the first objective lens. It is provided so as to be located on a first axis passing through the principal point of the second objective lens and on a second axis extending through the principal point of the second objective lens and extending in a direction perpendicular to the first axis. May be.
According to such a configuration, in addition to the effect of the above configuration in which the principal point of the second objective lens is maintained at one point before and after the posture adjustment, the adjustment hole is provided at a plurality of locations, so that the posture of the objective lens fixing frame is When performing the adjustment, it is possible to appropriately select an adjustment hole that is most suitable for posture adjustment and is suitable for the adjustment, and it is possible to further improve the production efficiency.

From another viewpoint, the present invention also provides an optical pickup equipped with the objective lens unit according to the present invention.
Here, the optical pickup according to the present invention preferably includes a plurality of laser light sources having different wavelengths so that laser beams having different wavelengths are irradiated from the plurality of objective lenses mounted on the objective lens unit. .

From another viewpoint, the present invention also provides an electronic device equipped with the optical pickup according to the present invention.
Here, as the electronic device, for example, a display device such as a television or a projector using an optical disk as an information storage medium, an imaging device such as a digital camera or a digital video camera, an information recording / reproducing device such as a digital recording / reproducing device or a digital audio player, Various electronic devices, such as a personal computer, a game machine, and an electronic dictionary, can be mentioned, and are not particularly limited.

  From another viewpoint, the present invention is a method for manufacturing the above-described objective lens unit according to the present invention, wherein when mounting a plurality of objective lenses on a main body, at least one objective lens is used as an objective lens fixing frame. It also provides a method for manufacturing an objective lens unit, which includes a step of holding and attaching to the main body, and operating the operating portion of the objective lens fixing frame via the adjustment hole of the main body to adjust the posture of the objective lens fixing frame.

  According to the method for manufacturing an objective lens unit according to the present invention, the posture of the objective lens held by the objective lens fixing frame can be easily and quickly adjusted from the outside. Since the objective lens can be adjusted much more easily than the conventional objective lens unit, and the workability is excellent, the production efficiency and the yield can be improved.

In the method of manufacturing the objective lens unit according to the present invention, a jig that can be inserted into the adjustment hole when the operating portion of the objective lens fixing frame is operated through the adjustment hole of the main body may be used.
According to such a structure, since the action part of the objective lens fixing frame is operated by the jig inserted into the adjustment hole of the main body, the workability becomes very good, and the posture can be adjusted more accurately.

  Hereinafter, an objective lens unit and a manufacturing method thereof according to embodiments of the present invention will be described in detail with reference to the drawings. In addition, in the several embodiment demonstrated below, the same code | symbol is attached | subjected and demonstrated to a common member.

Embodiment 1
1 is a plan view of an objective lens unit according to Embodiment 1 of the present invention, FIG. 2 is a left side view of the objective lens unit shown in FIG. 1, FIG. 3 is a cross-sectional view taken along line AA in FIG. FIG. 5 is a perspective view of a jig used when operating the action portion of the objective lens fixing frame in the method of manufacturing the objective lens unit according to the first embodiment, and FIGS. 5 and 6 are methods of manufacturing the objective lens unit according to the first embodiment. FIG. 6 is a process diagram illustrating a process in which the action portion of the objective lens fixing frame is operated by a jig to adjust the posture.

As shown in FIGS. 1 to 3, the objective lens unit 100 according to Embodiment 1 of the present invention includes a first objective lens 10 and a second objective lens 20 having different numerical apertures, and a first objective lens 10 and a second objective lens 10. , 20 mounted adjacent to each other, and an objective lens fixing frame 40 that holds the second objective lens 20 and is attached to the main body 30 so as to be capable of adjusting the posture.
An adjustment hole 31 is formed in the main body 30 so that a part of the objective lens fixing frame 40 attached to the main body 30 is exposed to the outside and the posture can be adjusted from the outside. The adjustment hole 31 is formed in the objective lens fixing frame 40. The action part 41 is formed in a part exposed to the outside through the.

The main body 30 has a circular seating surface 32 formed by a curved surface that is recessed in a concave shape at a portion where the objective lens fixing frame 40 is mounted.
On the other hand, the objective lens fixing frame 40 has a circular ring shape and an outer peripheral surface 42 formed of a curved surface curved in a convex shape so as to be slidable on the seating surface 32 of the main body 30.
As a result, the objective lens fixing frame 40 can be rotated around the principal point (optical center of the lens) of the second objective lens 20 by operating the operating portion 41 from the outside as will be described later. With the rotation of 40, the posture of the second objective lens 20 held by the objective lens fixing frame 40 is adjusted.

The action part 41 of the objective lens fixing frame 40 is configured by an elongated rectangular hole 43 formed in a part of the outer peripheral surface 42, and the adjustment hole 31 of the main body 30 exposes the action part 41 to the outside. Is formed.
That is, the action part 41 of the objective lens fixing frame 40 and the adjustment hole 31 of the main body 30 are arranged such that the action part 41 is exposed to the outside through the adjustment hole 31 and the principal point of the first objective lens 10 and the second objective lens 20. It is provided so that it may be located on the 1st axis line 51 which passes along the principal point.

Although not shown, the main body 30 can follow a track groove (a minute bit string) while being mounted on an optical pickup while responding to fluctuations in the position of the recording surface such as surface blurring and eccentricity caused by rotation of the optical disk. Further, an electromagnetic actuator for displacing the mounted first and second objective lenses 10 and 20 is provided.
The first and second objective lenses 10 and 20 are displaced by an actuator in a direction perpendicular to the recording surface of the optical disc (focusing direction) and a radial direction of the optical disc (tracking direction), respectively.

  By the way, the objective lens fixing frame 40 holding the second objective lens 20 is slidable on the seat surface 32 of the main body 30 in the manufacturing process of the objective lens unit 100 according to the present embodiment. This is because the mounting posture of the second objective lens 20 can be adjusted independently of the first objective lens 10 by adjusting the posture of the frame 40.

That is, the first objective lens 10 is an objective lens for irradiating the recording surface of a Blu-ray optical disc using a blue-violet laser having a wavelength of 405 nm as a light source, and it is necessary to narrow the laser beam spot to a diameter of about 0.5 μm. Therefore, the numerical aperture is larger than that of the second objective lens 20.
On the other hand, the second objective lens 20 is an objective lens for irradiating a recording surface of a DVD using a red laser having a wavelength of 660 nm as a light source and a CD using an infrared laser having a wavelength of 780 nm as a light source. The numerical aperture of the objective lens 10 is smaller.

For this reason, the mounting accuracy required when mounting the first objective lens 10 on the main body 30 is higher than the mounting accuracy required for the second objective lens 20, and the first objective lens 10 has priority over the second objective lens 20. Mounted on.
That is, after the first objective lens 10 is mounted on the main body 30, the coma aberration measured by the focal aberration adjuster using the actuator provided in the main body, and the jitter value obtained by actually irradiating the optical disc. The position is adjusted so that the mounting position becomes the best by the signal output of the optical pickup according to the error rate.

On the other hand, since the numerical aperture of the second objective lens 20 is smaller than the numerical aperture of the first objective lens 10, the mounting accuracy as high as that of the first objective lens 10 is not required.
For this reason, the second objective lens 20 uses surface reflection on the surface of the second objective lens 20 obtained by allowing parallel light to enter the second objective lens 20, and the second objective lens 20 is parallel to the optical disc. It is mounted by a technique such as simply adjusting the posture.

  Of course, the method of adjusting the attitude of the second objective lens 20 is not limited to the above method. For example, the central axis of the first objective lens 10 is the first axis based on the attitude of the first objective lens 10 that has been adjusted in attitude. The attitude may be adjusted so as to be parallel to the central axis of the one objective lens 10, or, like the first objective lens 10, the optical pickup based on the jitter value and error rate obtained by actually irradiating the optical disk may be used. The posture may be adjusted so that the mounting posture becomes the best by the signal output.

  The objective lens fixing frame 40 whose posture has been adjusted is fixed to the main body 30 by a resin adhesive such as an ultraviolet curable adhesive, a thermosetting adhesive, or a cyanoacrylate adhesive.

Hereinafter, the process of adjusting the posture of the objective lens fixing frame 40 will be described with reference to FIGS.
In this embodiment, the jig 60 shown in FIG. 4 is used when adjusting the posture of the objective lens fixing frame 40. As shown in FIG. A square flat plate portion 61 corresponding to a square hole 43 forming 41 is provided at the tip.

As shown in FIG. 5A, after the flat plate portion 61 of the jig 60 is inserted into the hole 43 that forms the action portion 41 of the objective lens fixing frame 40 through the adjustment hole 31 of the main body 30, FIG. ), When the jig 60 is moved in the upward direction in the drawing, the objective lens fixing frame 40 rotates around the second axis 52 (see FIG. 1).
At this time, the second objective lens 20 held by the objective lens fixing frame 40 also rotates about the second axis 52.
The second axis 52 extends in a direction perpendicular to the first axis 51 passing through the principal point of the first objective lens 10 and the principal point of the second objective lens 20, and the principal axis of the second objective lens 20. An axis passing through the point.

Further, as shown in FIG. 6A, the flat plate portion 61 (see FIG. 4) of the jig 60 is inserted into the hole 43 that forms the action portion 41 of the objective lens fixing frame 40 through the adjustment hole 31 of the main body 30. After that, when the jig 60 is rotated as shown in FIG. 6B, the objective lens fixing frame 40 rotates around the first axis 51 (see FIG. 1).
At this time, the second objective lens 20 held by the objective lens fixing frame 40 also rotates about the first axis 51.

Thus, according to the objective lens unit 100 according to the present embodiment, the jig 60 is inserted into the action part 41 of the objective lens fixing frame 40 through the adjustment hole 31 of the main body 30 and the action part 41 is operated. The posture of the objective lens fixing frame 40 can be adjusted.
Since the operation is performed from the outside using the jig 60, the workability is very good, and the mounting posture of the second objective lens 20 can be adjusted independently of the first objective lens 10 easily and quickly.
As a result, the production efficiency and yield of the objective lens unit 100 can be improved.

Embodiment 2
An objective lens unit and a manufacturing method thereof according to Embodiment 2 of the present invention will be described with reference to FIGS. 7 is a plan view of an objective lens unit according to Embodiment 2 of the present invention, FIG. 8 is a left side view of the objective lens unit shown in FIG. 7, FIG. 9 is a cross-sectional view taken along arrow BB in FIG. FIG. 11 is a perspective view of a jig used when operating the action part of the objective lens fixing frame in the method of manufacturing an objective lens unit according to the second embodiment. FIG. 11 is a diagram illustrating the objective lens in the method of manufacturing the objective lens unit according to the second embodiment. It is process drawing which shows the process in which the action part of a fixed frame is operated with a jig | tool, and an attitude | position is adjusted.

  As shown in FIGS. 7 to 9, the objective lens unit 200 according to the second embodiment of the present invention includes a pair of circular holes 243 in which the action portions 241 of the objective lens fixing frame 240 are arranged adjacent to each other. This is different from the objective lens unit 100 according to the first embodiment described above. Other configurations are the same as those of the objective lens unit 100 according to the first embodiment (see FIGS. 1 to 3).

The objective lens unit 200 according to the second embodiment includes a pair of circular holes 243 in which the action portions 241 of the objective lens fixing frame 240 are arranged adjacent to each other. Therefore, the action portions 240 of the objective lens fixing frame 240 are externally provided. In operation, a jig 260 shown in FIG. 10 is used.
As shown in FIG. 10, the jig 260 has a pair of cylindrical protrusions 261 at the tip corresponding to the pair of holes 243 forming the action portion 241 of the objective lens fixing frame 240.

  As shown in FIG. 11A, the pair of protrusions 261 (see FIG. 10) of the jig 260 are inserted into the pair of holes 243 that form the action portion 241 of the objective lens fixing frame 240 through the adjustment hole 31 of the main body 30. After the insertion, as shown in FIG. 11B, when the jig 260 is rotated, the objective lens fixing frame 240 rotates around the first axis 51 (see FIG. 7), and at the same time, the second The objective lens 20 also rotates about the first axis 51.

  Although not shown, when the jig 260 inserted in the action portion 241 is not rotated but moved upward, the objective lens fixing frame 240 rotates around the second axis 52 (see FIG. 7). At the same time, the second objective lens 20 also rotates around the second axis 52.

  In the second embodiment, the action part 241 of the objective lens fixing frame 240 is constituted by a pair of adjacent holes 243, and the jig 260 for operating the action part 241 also has a pair of protrusions 261 corresponding thereto. The action part 241 moves accurately in response to the above operation, and precise posture adjustment is facilitated. As a result, posture adjustment can be performed with higher accuracy.

Embodiment 3
An objective lens unit and a manufacturing method thereof according to Embodiment 3 of the present invention will be described with reference to FIGS. 12 is a plan view of an objective lens unit according to Embodiment 3 of the present invention, FIG. 13 is a front view of the objective lens unit shown in FIG. 12, and FIG. 14 is a left side view of the objective lens unit shown in FIG. 15 is a cross-sectional view taken along the line CC in FIG. 12, FIG. 16 is a cross-sectional view taken along the line DD in FIG. 12, and FIG. 17 is a diagram illustrating the action portion of the objective lens fixing frame in the manufacturing method of the objective lens unit according to the third embodiment. 18 is a perspective view of a jig used for operation, and FIG. 18 and FIG. 19 show a process in which the working portion of the objective lens fixing frame is operated by the jig and the posture is adjusted in the method of manufacturing the objective lens unit according to the third embodiment. It is process drawing shown.

As shown in FIGS. 12 to 16, in the objective lens unit 300 according to Embodiment 3 of the present invention, the action part 341 of the objective lens fixing frame 340 is formed along the outer peripheral surface 342 of the objective lens fixing frame 340. A groove 343 is formed.
The main body 330 is formed with circular adjustment holes 331 on the first axis 51 and the second axis 52, respectively.
Other configurations are the same as those of the objective lens unit 100 according to the first embodiment (see FIGS. 1 to 3).

The objective lens unit 300 according to Embodiment 3 uses the jig 360 shown in FIG. 17 when operating the action portion 341 of the objective lens fixing frame 340.
As shown in FIG. 17, the jig 360 used in the third embodiment has a protrusion 361 eccentric from the axial center at the tip.

  As shown in FIG. 18A, the projection 361 of the jig 360 is made to act by the objective lens fixing frame 340 through the adjustment hole 331 of the main body 330 formed on the first axis 51 (see FIG. 12). When the jig 360 is rotated as shown in FIG. 18B after being inserted into the groove 343 forming the portion 341, the eccentric protrusion 361 moves upward, and the objective lens fixing frame 340 is moved in the first direction. Rotate about the second axis 52 (see FIG. 12). As a result, the second objective lens 20 also rotates about the second axis 52.

  Further, as shown in FIG. 19A, the projection 361 of the jig 360 is inserted into the objective lens fixing frame 340 via the adjustment hole 331 of the main body 330 formed on the second axis 52 (see FIG. 12). When the jig 360 is rotated as shown in FIG. 19B after being inserted into the groove 343 forming the action portion 341, the eccentric protrusion 361 moves upward, and accordingly, the objective lens fixing frame 340 is moved. Rotates about the first axis 51 (see FIG. 12). As a result, the second objective lens 20 also rotates about the first axis 51.

In the third embodiment, since the acting portion 341 of the objective lens fixing frame 340 is operated by the eccentric protrusion 361 of the jig 360, the vertical movement distance of the protrusion 361 with respect to the rotation angle of the jig 360 is reduced, and precise posture adjustment is performed. Is easier to do. As a result, posture adjustment can be performed with higher accuracy.
Note that, by rotating the jig 360, a force is applied to the objective lens fixing frame 340 in order to rotate the objective lens fixing frame 340 in the circumferential direction, but it does not affect the performance of the optical pickup (within about 10 °). ) Is not a problem.

  Further, since the adjustment holes 331 are respectively formed on the first axis 51 and the second axis 52, it is possible to appropriately select and adjust the adjustment holes suitable for the adjustment, thereby relaxing the restrictions on the production process. Is done. Thereby, further improvement in production efficiency and yield can be achieved.

  Although not illustrated, the objective lens units 100, 200, and 300 according to the first to third embodiments obtained by adjusting the attitude as described above are a plurality of types of laser light sources that emit laser light having a wavelength corresponding to the type of the optical disk, If it is mounted on an optical pickup body equipped with grading (diffraction grating), 1/2 wavelength plate, dichroic prism, half mirror (beam splitter), collimator lens, 1/4 wavelength plate, rising mirror, optical sensor, etc. An optical pickup corresponding to a plurality of types of optical disks such as a system, a DVD, and a CD can be obtained.

  An electronic device equipped with such an optical pickup can use a plurality of types of optical disks such as a Blu-ray system, a DVD, and a CD as an information recording medium, and is very convenient.

It is a top view of the objective lens unit which concerns on Embodiment 1 of this invention. FIG. 2 is a left side view of the objective lens unit shown in FIG. 1. It is AA arrow sectional drawing of FIG. In the manufacturing method of the objective lens unit which concerns on Embodiment 1, it is a perspective view of the jig | tool used when operating the action part of an objective lens fixed frame. In the manufacturing method of the objective lens unit which concerns on Embodiment 1, it is process drawing which shows the process in which the action part of an objective lens fixed frame is operated with a jig | tool, and an attitude | position is adjusted. In the manufacturing method of the objective lens unit which concerns on Embodiment 1, it is process drawing which shows the process in which the action part of an objective lens fixed frame is operated with a jig | tool, and an attitude | position is adjusted. It is a top view of the objective lens unit which concerns on Embodiment 2 of this invention. FIG. 8 is a left side view of the objective lens unit shown in FIG. 7. It is BB arrow sectional drawing of FIG. In the manufacturing method of the objective lens unit which concerns on Embodiment 2, it is a perspective view of the jig | tool used when operating the action part of an objective-lens fixed frame. In the manufacturing method of the objective lens unit which concerns on Embodiment 2, it is process drawing which shows the process in which the action part of an objective lens fixed frame is operated with a jig | tool, and an attitude | position is adjusted. It is a top view of the objective lens unit which concerns on Embodiment 3 of this invention. FIG. 13 is a front view of the objective lens unit shown in FIG. 12. FIG. 13 is a left side view of the objective lens unit shown in FIG. 12. It is CC sectional view taken on the line of FIG. It is DD sectional view taken on the line of FIG. In the manufacturing method of the objective lens unit which concerns on Embodiment 3, it is a perspective view of the jig | tool used when operating the action part of an objective lens fixed frame. In the manufacturing method of the objective lens unit which concerns on Embodiment 3, it is process drawing which shows the process in which the action part of an objective lens fixed frame is operated with a jig | tool, and an attitude | position is adjusted. In the manufacturing method of the objective lens unit which concerns on Embodiment 3, it is process drawing which shows the process in which the action part of an objective lens fixed frame is operated with a jig | tool, and an attitude | position is adjusted.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 1st objective lens 20 2nd objective lens 30,330 Main body 31,331 Adjustment hole 32 Seat surface 40,240,340 Objective lens fixed frame 41,241,341 Action part 42,342 Outer peripheral surface 43,243 Hole 51 1st Axis 52 52 Second axis 60, 260, 360 Jig 61 Flat plate part 261, 361 Protrusion 100, 200, 300 Objective lens unit 343 Groove

Claims (13)

  A plurality of objective lenses having different numerical apertures, a main body on which the objective lenses are mounted adjacent to each other, and an objective lens fixing frame that holds at least one objective lens and is mounted on the main body so that the posture can be adjusted. The main body is formed with at least one adjustment hole that allows a part of the objective lens fixing frame attached to the main body to be exposed to the outside to adjust the posture from the outside. An objective lens unit in which an action part exposed to the outside through a hole is formed.   The main body has a circular seating surface formed by a concavely curved surface at a portion where the objective lens fixing frame is mounted, and the objective lens fixing frame has a circular ring shape and can slide on the seating surface. The objective lens unit according to claim 1, wherein the objective lens unit has an outer peripheral surface formed of a curved surface protruding in a convex shape.   The objective lens unit according to claim 2, wherein the action portion of the objective lens fixing frame is provided on the outer peripheral surface of the objective lens fixing frame, and the adjustment hole of the main body is provided so as to penetrate the seating surface.   The objective lens unit according to claim 3, wherein the action portion of the objective lens fixing frame includes a hole or a groove formed on an outer peripheral surface of the objective lens fixing frame.   The objective lens unit according to claim 1, wherein the objective lens fixing frame is fixed to the main body in the posture after the posture adjustment.   The objective lens unit according to any one of claims 1 to 5, wherein the plurality of objective lenses includes a first objective lens and a second objective lens, and the first objective lens has a larger numerical aperture than the second objective lens. .   The main body includes an actuator for adjusting the postures of the mounted first and second objective lenses, the objective lens fixing frame holds the second objective lens, and the first objective lens is directly fixed to the main body. Objective lens unit.   The objective lens unit according to claim 7, wherein the action portion of the objective lens fixing frame and the adjustment hole of the main body are provided so as to be positioned on an axis passing through the principal point of the first objective lens and the principal point of the second objective lens.   The working portion of the objective lens fixing frame and the adjustment hole of the main body are arranged on the first axis passing through the principal point of the first objective lens and the principal point of the second objective lens, and through the principal point of the second objective lens. 8. The objective lens unit according to claim 7, wherein the objective lens unit is provided so as to be positioned on a second axis extending in a direction orthogonal to the axis.   An optical pickup equipped with the objective lens unit according to claim 1.   An electronic device equipped with the optical pickup according to claim 10.   The method of manufacturing an objective lens unit according to claim 1, wherein when mounting a plurality of objective lenses on the main body, at least one objective lens is held on the objective lens fixing frame and attached to the main body, and an adjustment hole of the main body is mounted. The manufacturing method of the objective lens unit including the process of adjusting the attitude | position of an objective-lens fixed frame by operating the effect | action part of an objective-lens fixed frame via this.   13. The method of manufacturing an objective lens unit according to claim 12, wherein a jig that can be inserted into the adjustment hole is used when operating the action portion of the objective lens fixing frame via the adjustment hole of the main body.

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