JP2013030256A - Optical element, manufacturing method for optical element, and manufacturing method for light-assisted magnetic recording head - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an optical element easy for handling, a manufacturing method for the same, and a manufacturing method for a light-assisted magnetic recording head using such the optical element.SOLUTION: An optical element is utilized for a light-assisted magnetic recording head in which a light source is provided on a slider having an optical waveguide, and includes a holding part and a mirror part. The holding part is made of a bar-like member. The mirror part is provided on a portion of the holding part, and has a reflection surface formed, which makes light from the light source reflect toward the optical waveguide.

Description

  The present invention relates to an optical element, a method for manufacturing the optical element, and a method for manufacturing an optically assisted magnetic recording head using the optical element.

  In a magnetic recording system used for a hard disk drive (HDD), when an attempt is made to increase the recording density, the interval between magnetic bits becomes narrow, and the polarity becomes unstable due to a superparamagnetic effect or the like. For this reason, a recording medium having a high coercive force is required. However, when such a recording medium is used, a magnetic field required for recording also increases. Here, the upper limit of the magnetic field generated by the recording head is determined by the saturation magnetic flux density, but the value is approaching the material limit, and there is a fact that a dramatic increase cannot be expected. Therefore, during recording, the magnetic bit is heated locally to cause magnetic softening, recording is performed with a reduced coercive force, and then the heating is stopped and natural cooling is performed to stabilize the recorded magnetic bit. A recording method that guarantees the performance has been proposed. This method is called a “thermally assisted magnetic recording method”.

  In the heat-assisted magnetic recording method, it is desirable that the recording medium is instantaneously heated. Further, the heating mechanism and the recording medium rotating at high speed are not allowed to contact. Therefore, the heating is generally performed by irradiating a recording medium with a laser beam of a minute spot. This method using light for heating is called an “optically assisted magnetic recording method”.

  In the optically assisted magnetic recording method, how to form a minute light spot for heating the recording medium is an important point for improving the recording density. In this regard, it has been fixed in a direction to realize a spot size of several tens of nanometers using near-field light.

  As a technique for generating near-field light, an optical waveguide is laminated on a slider of an optically assisted magnetic recording head together with a magnetic recording / reproducing unit (magnetic head unit) using a semiconductor integrated circuit manufacturing process, and the optical waveguide emits light on the recording medium side. A method of generating near-field light by forming a plasmon probe near the end and irradiating the plasmon probe with light from an optical waveguide is becoming mainstream.

  As a transmission optical system for coupling light from a light source such as a semiconductor laser (LD) to an optical waveguide, the light emitted from the LD is deflected and condensed toward the incident surface of the optical waveguide. There is a system in which an optical element having a function of coupling light to an optical waveguide is disposed on a slider.

  For example, in the optically assisted magnetic head described in Patent Document 1, the light emitted from the LD is deflected by 90 ° by the surface reflection type deflection mirror and is applied to the optical waveguide. By using such a surface reflection mirror, the LD can be placed horizontally on the slider, and the head can be made thinner.

JP 2011-60408 A

  When an optical element is used for an optically assisted magnetic recording head, there is a problem that the optical element is very small and handling becomes difficult.

  An object of the present invention is to solve the above-described problems, and to provide an optical element that is easy to handle, a manufacturing method thereof, and a manufacturing method of an optically assisted magnetic recording head using such an optical element. .

In order to solve the above problems, an optical element according to claim 1 is an optical element used in an optically assisted magnetic recording head in which a light source is provided on a slider having an optical waveguide, and includes a gripping part, a mirror part, Have The gripping part is made of a rod-shaped member. The mirror part is provided in a part of the grip part, and a reflection surface for reflecting light from the light source toward the optical waveguide is formed.
An optical element according to a second aspect is the optical element according to the first aspect, wherein the gripping portion is engaged with an engaging portion provided on the slider.
An optical element according to a third aspect is the optical element according to the first or second aspect, wherein the mirror portion has an abutting surface that abuts an emission surface of the light source including an emission end from which light is emitted.
An optical element according to claim 4 is the optical element according to any one of claims 1 to 3, wherein the grip portion has a cylindrical shape having an inner peripheral surface, and the reflection surface of the mirror portion has an inner peripheral surface. It is a curved surface consisting of 1/4 of the surface.
An optical element according to a fifth aspect is the optical element according to the fourth aspect, wherein the center of the outer diameter of the grip portion and the center of the reflecting surface in the radial direction are coaxial.
A method for manufacturing an optical element according to claim 6 is a method for manufacturing the optical element according to claim 5. The manufacturing method of an optical element has a cutting process and a mirror part formation process. In the cutting step, a part of the cylindrical rod-shaped member is cut in a first direction orthogonal to the axial direction of the rod-shaped member, thereby leaving ½ of the entire circumference. In the mirror part forming step, the portion remaining in the cutting step is cut in the axial direction and in the second direction orthogonal to the first direction, leaving 1/4 of the entire circumference, so that the inner peripheral surface of the rod-shaped member is A mirror part as a reflection surface is formed.
According to a seventh aspect of the present invention, there is provided a method for manufacturing an optically assisted magnetic recording head comprising a placing step, a positioning step, and a fixing step. In the placing step, the light source is placed on the slider having the optical waveguide. In the positioning step, the holding portion of the optical element is engaged with the engaging portion formed in advance on the slider, and the mirror portion of the optical element is provided with respect to the emission surface of the light source including the emission end from which light is emitted. The optical element is positioned by abutting against the contact surface. In the fixing step, the optical element is fixed to the light source in the positioned state.

  By forming the grip portion on the optical element, the size of the optical element itself can be made relatively large even if the mirror portion itself is very small. Therefore, handling of the optical element is facilitated.

  Moreover, an optical element having a gripping part and a mirror part can be manufactured by cutting a part of a cylindrical bar-like member and leaving 1/4 of the entire circumference. That is, an optical element that can be easily handled can be manufactured.

  In addition, the use of the optical element facilitates assembly of the optically assisted magnetic recording head. Further, by engaging the gripping portion of the optical element with an engaging portion formed in advance on the slider, and abutting the contact surface provided on the mirror portion of the optical element against the emission surface of the light source The optical element can be positioned with respect to the slider and the light source unit. Therefore, it is not necessary to adjust the position of the optical element with respect to the slider and the light source unit.

It is a perspective view which shows the information recording device which concerns on embodiment. 1 is a perspective view showing an optically assisted magnetic recording head according to an embodiment. It is sectional drawing which shows the optically assisted magnetic recording head which concerns on embodiment. It is sectional drawing which shows another structure of the optically assisted magnetic recording head concerning embodiment. It is a perspective view which shows another structure of the slider which concerns on embodiment. It is a perspective view which shows the optical element which concerns on embodiment. It is sectional drawing which shows the optical element which concerns on embodiment. It is a perspective view which shows another structure of the optical element which concerns on embodiment. It is sectional drawing which shows another structure of the optical element which concerns on embodiment. It is a flowchart which shows the manufacturing process of the optical element which concerns on embodiment. It is a figure which supplements description of the flowchart of FIG. It is a figure which supplements description of the flowchart of FIG. It is a figure which supplements description of the flowchart of FIG. It is a figure which shows the metal mold | die used for manufacture of the optical element which concerns on embodiment. It is a figure which shows the metal mold | die used for manufacture of the optical element which concerns on embodiment. It is a figure which shows the metal mold | die used for manufacture of the optical element which concerns on embodiment. 6 is a flowchart showing an assembly procedure of the optically assisted magnetic recording head according to the embodiment. It is a figure which supplements description of the flowchart of FIG. It is a figure which supplements description of the flowchart of FIG.

[Configuration of information recording device]
As shown in FIG. 1, an optically assisted magnetic recording device (for example, a hard disk device, hereinafter sometimes referred to as “information recording device 1”) equipped with an optically assisted magnetic recording head is capable of rotating a plurality of recording sheets, for example. A disk (magnetic recording medium) 3, a head support 5, a tracking actuator 7, an optically assisted magnetic recording head 4 (hereinafter sometimes referred to as “optical head 4”), and a drive device (not shown) are provided. It is provided in the body 2. The disk 3 may be one. The head support portion 5 is provided to be rotatable in the direction of arrow A (tracking direction) with the support shaft 6 as a fulcrum. The tracking actuator 7 is attached to the head support portion 5. The optical head 4 is attached to the tip of the head support 5. A drive device (not shown) rotates the disk 3 in the direction of arrow B. The information recording apparatus 1 is configured such that the optical head 4 can move relatively while flying over the disk 3.

[Optical assisted magnetic recording head]
Next, a schematic configuration example of the optical head 4 will be described with reference to FIGS. 2 to 6B. FIG. 2 is a perspective view of the optical head 4. FIG. 3 is a sectional view (DD section) of the optical head 4. FIG. 5A is a perspective view of the optical element 30. FIG. 5B is a cross-sectional view (E-E cross section) of the optical element 30.

  The optical head 4 is a minute optical recording head that uses light for information recording on the disk 3. As shown in FIG. 2, the optical head 4 includes a slider 10, a light source unit 20, and an optical element 30. The information recording apparatus 1 is configured to move the disk 3 in the direction of arrow C (see FIG. 3) so that the optical head 4 can move relatively while floating on the disk 3. In this embodiment, the rotation direction (arrow C direction) of the disk 3 is described as the y direction, the thickness direction of the optical head 4 is described as the z direction, and the direction orthogonal to both the y direction and the z direction is described as the x direction.

(Slider)
The slider 10 is a square substrate formed of a material such as AlTiC, for example. As shown in FIG. 3, the slider 10 has a lower surface 10a facing the disk 3, an upper surface 10b located on the opposite side of the lower surface 10a in the z direction, and a side surface 10c.

  A magnetic head portion 13 is formed on the slider 10. The magnetic head unit 13 includes an optical waveguide 14, a magnetic recording unit (not shown), a magnetic information reproducing unit (not shown), and an electrode (not shown). In the present embodiment, the magnetic head portion 13 is formed integrally with the slider 10, but a separate head may be attached to the side surface 10 c of the slider 10.

  Further, as shown in FIG. 3, the magnetic head portion 13 is formed with a groove portion 16 in the x direction. A grip portion 31 (described later) of the optical element 30 is engaged with the groove portion 16. In the present embodiment, a V-shape is used as the shape of the groove 16. The groove 16 in the present embodiment is an example of an “engagement portion”. By engaging a grip portion 31 (described later) with the groove portion 16, the optical element 30 can be positioned with respect to the slider 10 without fine position adjustment.

The optical waveguide 14 guides light from the light source unit 20 guided by the optical element 30 and forms a path for emitting the light toward the disk 3. The optical waveguide 14 has an incident end 14a and an exit end 14b. Light from the light source unit 20 is incident on the incident end 14a. The incident end 14 a is provided at the bottom of the groove 16. Light that has passed through the optical waveguide 14 is emitted from the emission end 14b. The emission end 14 b is provided on the lower surface of the magnetic head portion 13 that is substantially flush with the lower surface 10 a of the slider 10. The optical waveguide 14 is formed by laminating a lower clad layer, a core layer, and an upper clad layer (all of which are not shown) in this order along a thickness direction orthogonal to a direction in which light propagates. The core layer is formed of a material (for example, Ta ₂ O ₅ ) having a higher refractive index than each cladding layer (for example, formed of SiO ₂ ). Thereby, the light guided to the optical waveguide 14 propagates toward the disk 3 while being totally reflected between the core layer and each cladding layer.

  In the vicinity of the emission end 14b of the optical waveguide 14, a plasmon probe 15 as a near-field light generating element is disposed.

  The light from the light source unit 20 guided by the optical element 30 enters the optical waveguide 14 from the incident end 14a and travels in the optical waveguide 14 toward the output end 14b. The plasmon probe 15 provided at the emission end 14 b converts the light guided by the optical element 30 into near-field light and emits it toward the disk 3.

  A magnetic recording unit (not shown) writes magnetic information to the recording portion of the disk 3. A magnetic information reproducing unit (not shown) reads magnetic information recorded on the disk 3. An electrode (not shown) is formed on the upper surface 10 b of the slider 10. The electrodes have a predetermined pattern shape and are connected to the light source unit 20 to supply driving power to the light source unit 20.

Further, the slider 10 moves relative to the disk 3 that is a magnetic recording medium while flying, but there is a possibility of contact with the disk 3 if there is a dust attached to the disk 3 or a defect in the disk 3. There is. In order to reduce the friction generated in that case, it is preferable to use a hard material having high friction resistance as the material of the slider 10. For example, a ceramic material containing Al ₂ O ₃ , AlTiC, zirconia, TiN, or the like may be used. In order to prevent friction, the surface of the slider 10 on the disk 3 side may be subjected to a surface treatment for increasing the friction resistance. For example, high hardness can be obtained by using a DLC (Diamond Like Carbon) coating.

(Slider variation)
The shape of the groove portion 16 is not limited to the V shape as long as the grip portion 31 (described later) can be engaged. For example, as shown in FIG. 4A, the groove 16 may be square. In this case, the incident end 14 a is provided on the bottom surface of the groove 16.

  Alternatively, as shown in FIG. 4B, a configuration in which the V-shaped groove 16 is provided only in a portion where the grip portion 31 (described later) is engaged may be used. In this case, a flat surface 17 that is flush with the upper surface 10 b of the slider 10 is formed in a portion where the groove portion 16 is not provided. In FIG. 4B, the description of the incident end 14a of the optical waveguide 14 is omitted.

  In any of the modifications, the optical element 30 can be positioned with respect to the slider 10 by engaging the grip portion 31 (described later) with the groove portion 16.

(Light source)
The light source unit 20 includes, for example, a semiconductor laser. The light source unit 20 outputs light in a direction substantially orthogonal to the optical waveguide 14. The “substantially orthogonal direction” refers to a direction in which light from the light source unit 20 can enter a reflecting surface 32a (described later) of the optical element 30. The wavelength of light output from the semiconductor laser is from visible light to near-infrared wavelength (the wavelength band is about 0.6 μm to 2 μm. Specific wavelengths are 650 nm, 780 nm, 830 nm, and 1310 nm. , 1550 nm, and the like.

  As a material constituting the semiconductor laser, for example, any one of materials such as GaAs, AlGaAs, InGaAs, AlGaInP, InAlGaN, InGaN, GaN, GaInNA, GaNAsP, and AlGaNAs may be used. Then, a semiconductor laser can be manufactured by stacking layers necessary for light emission on the wafer.

  The light source unit 20 is disposed on the upper surface 10 b of the slider 10. The light source unit 20 has an emission surface 20a and a bottom surface 20b. On the emission surface 20a, an emission end 20c for emitting light from the semiconductor laser to the outside of the light source unit 20 is formed. The light source unit 20 outputs light from the emission end 20 c toward the optical element 30.

(Optical element)
The optical element 30 is an element for reflecting and condensing light from the light source unit 20 and guiding it to the incident end 14 a of the optical waveguide 14. The optical element 30 is made of, for example, an optically transparent resin or glass. As shown in FIG. 5A, in this embodiment, the optical element 30 includes a grip portion 31 and a mirror portion 32.

  The grip portion 31 is a portion that is gripped when the optical element 30 is handled, such as when the optical head 4 is assembled. The grip portion 31 in the present embodiment is formed from a cylindrical rod-shaped member having an inner peripheral surface. Although the mirror portion 32 itself is very small, the size of the optical element 30 itself can be made relatively large by providing the grip portion 31. Therefore, the handleability of the optical element 30 can be secured, and the assembly of the optical head 4 is facilitated.

  The mirror part 32 is provided in a part of the rod-shaped member forming the grip part 31 (in the present embodiment, the middle part of the cylindrical rod-shaped member). The mirror unit 32 includes a reflection surface 32a, an end surface 32b, and an end surface 32c (see FIG. 5B). The reflecting surface 32a reflects and collects the light from the light source unit 20 and guides it to the incident end 14a of the optical waveguide 14. In the present embodiment, the reflecting surface 32a is a curved surface formed of a part (1/4) of the inner peripheral surface of the rod-shaped member. Further, in the present embodiment, the center of the outer diameter of the grip portion 31 that is cylindrical and the center of the reflecting surface 32a in the radial direction are coaxial.

  The reflection surface 32a only needs to be able to reflect and condense light from the light source unit 20 and guide the light to the incident end 14a of the optical waveguide 14. For example, the reflecting surface 32a may be a cylindrical surface formed of a part of an aspherical cross section such as an ellipse.

  Alternatively, the reflecting surface 32a may be a toric surface or an anamorphic surface. By using such a reflection surface 32a, it is possible to form a light spot shape suitable for the mode field distribution of the optical waveguide 14. Therefore, the coupling efficiency of the light from the light source unit 20 to the optical waveguide 14 can be improved. The reflective surface 32a may be a flat surface.

  The reflecting surface 32a may be plated in order to increase the reflection efficiency. For example, the plating process is performed using a material having high reflection efficiency such as gold plating after surface treatment is performed by electroless nickel plating to form a base.

  In the present embodiment, the reflecting surface 32a is exposed to the outside. Therefore, the reflecting surface 32a functions as a surface reflecting mirror. Since the reflecting surface 32 a is a surface reflecting mirror, the light from the light source unit 20 does not enter the optical element 30. Therefore, it is possible to reduce the light amount loss due to the light passing through the optical element 30. In addition, it is also possible to use the optical element 30 which has the reflective surface 32a inside.

  The end surface 32 b is a surface that is disposed to face the emission surface 20 a of the light source unit 20 when the optical element 30 is assembled to the slider 10. In this embodiment, when the optical element 30 is assembled | attached to the slider 10, the end surface 32b and the output surface 20a are comprised so that it may contact | abut (refer FIG. 3). That is, the end surface 32b in the present embodiment is an example of a “contact surface”. By bringing the end surface 32b and the emission surface 20a into contact with each other, the optical element 30 can be positioned with respect to the light source unit 20 without performing fine position adjustment. The end surface 32b can be joined to the emission surface 20a of the light source unit 20 via an adhesive or the like.

  The end face 32 c is disposed in the groove 16 when the optical element 30 is assembled to the slider 10.

  When the slider 10 has a shape as shown in FIG. 4B, the end face 32 c comes into contact with the flat surface 17 when the optical element 30 is assembled to the slider 10. By bringing the end face 32 c and the flat surface 17 into contact with each other, the optical element 30 can be positioned with respect to the slider 10. In this case, the end face 32c can be joined to the flat surface 17 via an adhesive or the like.

  Moreover, the area of the end surface 32b and the end surface 32c may be equal, and may differ (FIG. 3 etc. have shown the example with an equal area).

(Modification of optical element)
The rod-shaped member forming the optical element 30 is not limited to the cylindrical shape as long as the mirror part 32 can be formed. For example, a rectangular tube shape, a cylindrical shape, a prismatic shape, or the like may be used. In the case of a rectangular tube shape, the inner peripheral surface is preferably formed in a cylindrical shape.

  In addition, as shown in FIGS. 6A and 6B, the optical element 30 can be provided with a D-cut. FIG. 6A is a perspective view of the optical element 30. 6B is a cross-sectional view taken along line FF in FIG. 6A.

  After the optical element 30 is assembled to the slider 10 (light source unit 20), the optical element 30 (mirror unit 32) is finely adjusted so that the light emitted from the light source unit 20 enters the incident end 14a of the optical waveguide 14. May do. As this method, for example, an autocollimator is used.

  In this case, a part of the optical element 30 is cut (D cut) to provide the flat portion 30a. The flat surface portion 30a serves as a reflection surface when observing with an autocollimator from the upper surface of the optical head 4.

  When observation is performed from the upper surface of the optical head 4, it is desirable that the flat surface portion 30 a be provided in a direction (y direction) orthogonal to the end surface 32 b of the mirror portion 32. The optical element 30 provided with the flat portion 30a can be photographed from the side surface of the optical head 4, and the optical element 30 can be finely adjusted based on the photographing result.

[Method for Manufacturing Optical Element 30]
Next, a method for manufacturing the optical element 30 according to the present embodiment will be described with reference to FIGS. Here, two examples of the method for manufacturing the optical element 30 shown in FIG. 5A will be described. The first is a method of manufacturing the optical element 30 by processing the capillary 30 ′ (hereinafter sometimes referred to as “first method”). The second method is a method of manufacturing the optical element 30 by molding (hereinafter sometimes referred to as “second method”).

(First method)
The first method will be described with reference to FIGS. 7 to 8C. FIG. 7 is a flowchart showing the first method. 8A to 8C are perspective views of the capillary 30 '. 8A to 8C, the longitudinal direction of the capillary 30 'is the x direction, and one of the directions orthogonal to the x direction is the y direction and the other is the z direction.

  First, as shown in FIG. 8A, a part of a capillary 30 ′, which is a cylindrical rod-shaped member, is cut in the y direction perpendicular to the x direction, which is the axial direction of the capillary 30 ′, using a blade DB ( S10). Cutting with the blade DB is performed on a range d where the mirror portion 32 is to be formed. As shown in FIG. 8B, only a half of the entire circumference of the capillary 30 ′ remains in the portion cut by the blade DB in this way. The process of S10 in this embodiment is an example of a “cutting process”. Further, the y direction in the present embodiment is an example of the “first direction”.

  Next, the capillary 30 ′ cut in S10 is rotated by 90 ° with respect to the blade DB (S11; see arrow F in FIG. 8B). Then, as shown in FIG. 8C, the direction perpendicular to the axial direction (x direction) and y direction (first direction) of the capillary 30 ′ using the blade DB with respect to the same range as the range d cut in S 10 ( Cutting in the z direction) (S12). Thus, only a quarter of the entire circumference of the capillary 30 'remains in the portion cut by the blade DB. Therefore, as shown in FIG. 5A, it is possible to manufacture the optical element 30 on which the mirror portion 32 having the inner peripheral surface of the capillary 30 ′ as the reflecting surface 32a is formed (S13). The process of S12 in the present embodiment is an example of the “mirror part forming process”. Further, the z direction in the present embodiment is an example of the “second direction”. Since the first method uses the capillary 30 ′, the manufactured optical element 30 is coaxial with the center of the outer diameter of the cylindrical gripping portion 31 and the center of the reflecting surface 32 a in the radial direction. It has the composition which exists in.

  Note that the mirror portion 32 can also be formed by changing the position of the blade DB instead of rotating the capillary 30 'in S11.

(Second method)
Next, the second method will be described with reference to FIGS. 9 and 10 are perspective views showing a mold for forming the optical element 30. FIG. 11 is a cross-sectional view (GG cross section in FIG. 9) when the molds of FIGS. 9 and 10 are combined. In addition, in FIG. 11, the state before another core 52 is inserted is shown.

  As shown in FIGS. 9 and 10, the optical element 30 is formed by fitting two molds of a mold 50 and a mold 51. In the mold 50 and the mold 51, a molding part 50a and a molding part 51a corresponding to the shape of the optical element 30 are formed. In the mold 50, a space 50b (see FIG. 11) is formed in which another core 52 corresponding to the shape of the reflecting surface 32a of the mirror 32 is disposed.

  The separate core 52 can be exchanged according to the shape (curvature) of the desired reflecting surface 32a. That is, by using different cores 52, the optical elements 30 having different curvatures can be formed. Moreover, since it is only necessary to replace another core, it is not necessary to create the entire mold in accordance with the shape of the reflecting surface 32a. Therefore, the cost for manufacturing the optical element 30 can be suppressed.

  The optical element 30 manufactured by the second method is made of a resin material such as plastic. The resin material forming the optical element 30 flows in from the mold 50 or a hole (not shown) formed in the mold 51 in a state where the mold 50 and the mold 51 are combined.

[Method for Manufacturing Optical Head 4]
Next, a method for manufacturing the optical head 4 will be described with reference to FIGS. FIG. 12 is a flowchart showing an assembling procedure of the optical head 4. 13 and 14 are cross-sectional views of the optical head 4.

  First, as shown in FIG. 13, the light source unit 20 is placed on the upper surface 10b of the slider 10 (S30). The process of S30 in the present embodiment is an example of a “placement process”.

  Subsequently, the light source unit 20 is fixed to the slider 10 (S31). The light source unit 20 is fixed by, for example, soldering. In this case, a solder paste is applied in advance to the electrodes formed on the upper surface 10b of the slider 10. Then, after aligning the light source unit 20 with respect to the slider 10, the light source unit 20 is fixed to the slider 10 by infrared rays, hot air reflow, or the like.

  Next, as shown in FIG. 14, the optical element 30 is placed on the upper surface 10b of the slider 10 (S32). At this time, the optical element 30 can be easily assembled to the light source unit 20 by fitting the light source unit 20 into the portion where the mirror unit 32 is formed. Further, when the grip portion 31 of the optical element 30 is engaged with the groove portion 16, the optical element 30 is positioned with respect to the slider 10. Further, in the present embodiment, the reflecting surface 32a and the light source unit 20 can be easily positioned by bringing the end surface 32b of the mirror unit 32 into contact with the emission surface 20a of the light source unit 20 via the adhesive 40. it can. That is, the process of S32 in this embodiment is an example of a “positioning process”. As the adhesive 40, it is desirable to use, for example, an adhesive having ultraviolet curing characteristics or thermosetting characteristics.

  The optical element 30 is fixed with respect to the light source part 20 in the state positioned in S32 (S33, fixing step). For example, when the adhesive 40 having ultraviolet curing characteristics is used in S <b> 32, the optical element 30 is bonded and fixed to the light source unit 20 by irradiating ultraviolet rays. Thus, the optical head 4 in which the optical element 30 is positioned can be manufactured (see FIG. 2).

  In order to efficiently use the light from the light source unit 20, high coupling efficiency is required when the light is incident on the optical waveguide 14. Therefore, a strict positional relationship is required for the slider 10, the light source unit 20, and the optical element 30. That is, in manufacturing the optical head 4, the positioning of the slider 10, the light source unit 20, and the optical element 30 is important. “Coupling efficiency” refers to the rate at which light from the emission end 20 c of the light source unit 20 is coupled to the incident end 14 a of the optical waveguide 14.

  In the present embodiment, the example in which the emission surface 20a of the light source unit 20 and the end surface 32b of the mirror unit 32 are brought into contact with each other has been described. However, the mirror unit 32 can be positioned without contact. In other words, positioning to some extent is possible only by engaging the grip portion 31 with the groove portion 16.

[Action / Effect]
The operation and effect of this embodiment will be described.

  The optical element 30 according to the present embodiment is an optical element used for an optically assisted magnetic recording head (optical head 4) in which a light source unit 20 is provided on a slider 10 having an optical waveguide 14. The optical element 30 includes a grip portion 31 and a mirror portion 32. The grip part 31 is made of a rod-shaped member. The mirror part 32 is provided in a part of the grip part 31, and a reflection surface 32 a that reflects the light from the light source part 20 toward the optical waveguide 14 is formed.

  Thus, by forming the grip portion 31 together with the mirror portion 32 on the optical element 30, the size of the optical element 30 itself can be made relatively large even if the mirror portion 32 itself is very small. Therefore, handling of the optical element 30 is facilitated.

  Further, the grip portion 31 of the optical element 30 according to this embodiment is engaged with the groove portion 16 (engagement portion) provided in the slider 10. Moreover, the mirror part 32 has the end surface 32b (contact surface) contact | abutted to the output surface 20a of the light source part 20 containing the output end 20c from which light is radiate | emitted.

  As described above, the optical element 30 can be easily positioned with respect to the slider 10 (light source unit 20) by engaging the grip portion 31 with the groove portion 16 and bringing the end surface 32b into contact with the emission surface 20a. it can. That is, it is possible to save the trouble of position adjustment when the optical element 30 is arranged with respect to the slider 10 (light source unit 20).

  In addition, the grip portion 31 of the optical element 30 according to the present embodiment has a cylindrical shape having an inner peripheral surface, and the reflection surface 32a of the mirror portion 32 is formed by a curved surface that is 1/4 of the inner peripheral surface. . Further, the center of the outer diameter of the grip portion 31 and the center of the reflecting surface 32a in the radial direction are coaxial.

  As described above, the optical element 30 in which the center of the outer diameter of the grip portion 31 and the center of the reflecting surface 32a in the radial direction are coaxial can be easily manufactured only by processing a part of an existing capillary. That is, it is possible to easily manufacture the optical element 30 that is easy to handle.

  Moreover, the manufacturing method of the optical element 30 has a cutting process and a mirror part formation process. In the cutting step, a part of the cylindrical capillary 30 '(rod-like member) is cut in a first direction orthogonal to the axial direction of the capillary 30', leaving ½ of the entire circumference. In the mirror part forming step, the portion remaining in the cutting step is cut in the axial direction and the second direction orthogonal to the first direction, leaving 1/4 of the entire circumference, so that the inner peripheral surface of the capillary 30 ' Is formed as a reflecting surface 32a.

  Thus, by cutting a part of the cylindrical capillary 30 ′ and leaving ¼ of the entire circumference, the optical element 30 having the grip portion 31 and the mirror portion 32 and easy to handle can be manufactured. .

  Moreover, the manufacturing method of an optically assisted magnetic recording head (optical head 4) has a mounting process, a positioning process, and a fixing process. In the placing step, the light source unit 20 is placed on the slider 10 having the optical waveguide 14. In the positioning step, the gripping portion 31 of the optical element 30 is engaged with the groove portion 16 (engagement portion) formed in advance on the slider 10, and the emission surface of the light source unit 20 including the emission end 20c from which light is emitted is provided. The optical element 30 is positioned by abutting an end face 32b (contact surface) provided on the mirror portion 32 of the optical element 30 against 20a. In the fixing step, the optical element 30 is fixed to the light source unit 20 in a positioned state.

  Thus, the optical head 4 can be easily assembled by using the optical element 30 that is easy to handle. Furthermore, by using such an optical element 30, the optical element 30 can be easily positioned with respect to the slider 10 and the light source unit 20. Therefore, it is not necessary to adjust the position of the optical element 30 with respect to the slider 10 and the light source unit 20.

DESCRIPTION OF SYMBOLS 1 Information recording device 2 Housing 3 Disc 4 Optical assist magnetic recording head (optical head)
DESCRIPTION OF SYMBOLS 5 Head support part 6 Support axis 7 Tracking actuator 10 Slider 10a Lower surface 10b Upper surface 10c Upper surface 10c Side surface 13 Magnetic head part 14 Optical waveguide 14a Incidence end 14b Output end 15 Plasmon probe 16 Groove part 20 Light source part 20a Output surface 20b Bottom face 20c Output end 30 Element 31 Grip part 32 Mirror part 32a Reflective surface 32b, 32c End face

Claims (7)

An optical element used in an optically assisted magnetic recording head in which a light source is provided on a slider having an optical waveguide,
A grip portion made of a rod-shaped member;
A mirror part provided on a part of the grip part and formed with a reflection surface for reflecting light from the light source toward the optical waveguide;
An optical element comprising:   The optical element according to claim 1, wherein the grip portion is engaged with an engagement portion provided on the slider.   3. The optical element according to claim 1, wherein the mirror portion has an abutting surface that abuts on an emitting surface of the light source including an emitting end from which light is emitted.   The said holding | grip part is a cylindrical shape which has an internal peripheral surface, The reflective surface of the said mirror part is a curved surface which consists of 1/4 of the said internal peripheral surface. Optical elements.   The optical element according to claim 4, wherein the center of the outer diameter of the grip portion and the center of the reflecting surface in the radial direction are coaxial. It is a manufacturing method of the optical element according to claim 5,
Cutting a part of the cylindrical rod-shaped member in a first direction orthogonal to the axial direction of the rod-shaped member, thereby leaving a half of the entire circumference;
The portion remaining in the cutting step is cut in the axial direction and the second direction orthogonal to the first direction, leaving 1/4 of the entire circumference, thereby making the inner peripheral surface of the rod-shaped member a reflective surface A mirror part forming step for forming a mirror part;
A method for producing an optical element, comprising: A mounting step of mounting a light source on a slider having an optical waveguide;
An optical element holding part is engaged with an engagement part formed in advance on the slider, and provided on a mirror part of the optical element with respect to an emission surface of the light source including an emission end from which light is emitted. Positioning step of positioning the optical element by abutting the contact surface
A fixing step of fixing the optical element to the light source in the positioned state;
A method of manufacturing an optically assisted magnetic recording head, comprising:

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