JP2009053529A - Method of forming optical component attachment surface and method of manufacturing optical pickup - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of forming optical component attachment surface, which can be included into a manufacturing process and is capable of setting the position and angle of an optical component highly accurately. <P>SOLUTION: Upon the formation of the optical component attachment surface, a housing 11 having a plurality of protrusions 32 formed on a mount position 31 of the optical component is prepared in the first place. Subsequently, the housing 11 is set on a table 41 of a press device 40 and a press process of the protrusions 32 of the housing 11 is performed. On the press process, a press head 42 is caused to straightly fall, tips of the protrusions 32 disposed on the mount position 31 of the optical component are crushed and flat surfaces parallel to a bottom surface (reference surface) 36 of the housing are formed. Thereby, heights of the protrusions which have a certain variation of heights are made even and the parallelism for the reference surface is also secured highly accurately. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a method for forming an optical component mounting surface, and particularly to a method for forming a reference surface for setting the position and angle of an optical component with high accuracy. The present invention also relates to a method of manufacturing an optical pickup using this method for forming an optical component mounting surface.

  An optical recording / reproducing apparatus that records and reproduces data on an optical disc such as a CD, DVD, or Blu-ray disc includes an optical pickup. The optical pickup has a configuration in which various optical components such as a laser diode, a photodiode, an objective lens, and a deflection beam splitter are provided in a housing molded by die casting such as aluminum alloy. The assembly accuracy of these optical components is very important for realizing high performance of the optical pickup, and how easy it is to realize the mounting accuracy of the optical components is the cost reduction and high cost of the optical pickup. It is an important key to improve performance.

  In order to improve the mounting accuracy of the optical component, for example, in Patent Document 1, two convex portions protruding from the side wall surface of the housing are formed integrally with the housing, and the tip surfaces of these convex portions are formed on the optical component. It is disclosed that it is used as a reference surface for positioning with which a side surface abuts.

Further, in Patent Document 2, mounting portions for fixing the reflecting mirror at a predetermined angle are provided in the carriage, and protrusions that linearly contact the reflecting mirror are formed at three locations in the mounting portion. An optical pickup is described in which the mounting accuracy of the reflecting mirror is improved by supporting the reflecting mirror at three points. Further, in Patent Document 3, a concave portion for storing an adhesive and a contact portion that protrudes from the concave portion and contacts the reflection mirror are formed on an inclined installation surface on which the reflection mirror is installed. It has been disclosed to prevent dripping and stabilize the mounting angle of the reflecting mirror. Three concave portions and three contact portions are provided, and these are alternately arranged in a triangular shape with the vertexes reversed.
JP-A-9-274123 JP 2003-151146 A JP 2001-250258 A

  In the conventional optical pickups described in Patent Documents 1 to 3, a plurality of protrusions are formed on the mounting surface of the optical component, thereby ensuring the accuracy of the position and angle of the mounting surface of the optical component. These protrusions are molded integrally with the housing by die casting. Since the surface of the housing thus molded is formed with minute protrusions and irregularities, there is some variation in the height of the protrusions. There is a problem that the flatness and parallelism of the optical component mounting surface cannot be ensured. In particular, the flatness in the mounting area of small components such as optical components is impaired by only a few irregularities.

  Further, the protrusion can be formed by cutting after molding of the housing, but when the protrusion is formed with normal processing accuracy, it is difficult to obtain flatness suitable for the mounting surface of the optical component. When a very high-precision cutting machine is used, a desired flatness can be obtained. However, since such an apparatus is very expensive, there is a problem that the manufacturing cost is increased. Further, when the protrusion is formed by cutting, shavings are generated, and thus there is a problem that the protrusion forming process cannot be incorporated into the optical pickup production line.

  Accordingly, an object of the present invention is to provide a method for forming an optical component mounting surface that can be included in the manufacturing process of an optical pickup and that can set the position and angle of the optical component with high accuracy. is there.

  The object of the present invention is to prepare a housing in which at least three protrusions are integrally formed for each mounting position of one optical component, and to set the tips of the at least three protrusions at a predetermined angle with respect to a predetermined reference plane. And a step of forming a mounting surface of the optical component by crushing with a flat surface having an optical component mounting surface.

  In the present invention, the predetermined reference surface is preferably the bottom surface of the housing. Since the bottom surface of the housing is sufficiently wider than the mounting area of the optical component, the parallelism to the disk surface can be sufficiently secured, and it can be used as a reference surface for the optical component mounting surface.

  In the present invention, the housing has mounting positions for a plurality of optical components, and is a plane having different heights for each mounting position of each optical component with respect to at least three protrusions provided at the mounting positions of each optical component. It is preferable to vary the height of the mounting surface of the optical component by crushing with. According to this, a plurality of attachment surfaces having different heights can be formed simultaneously.

  In the present invention, the housing may be molded by die casting or may be made of a resin material. In either case, by crushing the tip of the protrusion provided at the mounting position of the optical component to form a plane parallel to the predetermined reference plane, the height of the protrusion with some height variation is uniform. The parallelism with respect to the reference plane is ensured with high accuracy.

  The above-mentioned object of the present invention also provides a step of preparing a housing in which at least three protrusions are integrally formed for each mounting position of one optical component, and the tips of the at least three protrusions are predetermined with respect to a predetermined reference plane. Also achieved by a method of manufacturing an optical pickup, comprising: a step of forming a mounting surface of an optical component by crushing on a plane having an angle; and a step of bonding an optical component corresponding to a mounting position of the optical component Is done.

  As described above, according to the present invention, the mounting surface of the optical component can be easily formed, and no shavings are generated. Therefore, the protrusion forming step can be included in the manufacturing process of the optical pickup. Therefore, optical components can be mounted with high accuracy, and a highly reliable and high performance optical pickup can be realized.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

  FIG. 1 is a schematic perspective view showing an example of the configuration of an optical pickup.

  As shown in FIG. 1, the optical pickup 100 includes a housing 11, two laser diodes 12 and 13 fixed to the side surface of the housing 11, diffraction gratings 14 and 15 housed inside the housing 11, and a dichroic prism 16. , An optical component such as a deflection beam splitter 17, a rising mirror 18, a sensor lens 19, and a photodiode 20 that is a light receiving element. Further, an objective lens (not shown) for condensing the laser light, an objective lens driving mechanism 21 for driving the objective lens, and a control circuit board 22 are provided. Among these, passive optical components such as the dichroic prism 16, the deflecting beam splitter 17, and the rising mirror 18 are required to have high positional accuracy with respect to the optical axis of the laser beam. Therefore, the flatness of their mounting surfaces is very important. It is. Therefore, the mounting surfaces of these optical components are formed by the following method.

  2 to 4 are schematic views for explaining a method of forming the optical component mounting surface. Among these, FIG. 2 is a schematic diagram showing the structure of the housing 11, FIG. 3 is a schematic diagram for explaining the pressing process of the protrusions, and FIG. 4 is a schematic diagram showing the bonding process of the optical component. .

  In forming the optical component mounting surface, first, a housing 11 is prepared as shown in FIG. In the present embodiment, a housing formed by die casting of an aluminum alloy can be used. The above-described various optical components are mounted on the housing 11, and a plurality of protrusions 32 are formed at the mounting position 31 of the optical component in the housing 11, and a plane as a mounting surface of the optical component is formed by these protrusions 32. Is defined. For example, three protrusions as shown in the figure are formed at the mounting position of the dichroic prism 16. The number of the protrusions 32 is not particularly limited as long as a plane can be defined. Any number of protrusions 32 or more is acceptable as long as the number is three or more. Therefore, the number of protrusions should be as small as possible. Therefore, the number of protrusions 32 is preferably 4 or less, and most preferably 3.

  In the present embodiment, the shape of the protrusion 32 is substantially conical, and the shapes of all the protrusions formed at the mounting positions of the optical components are substantially the same. However, since it is adjusted in the press process described later, strict identity is not required, and there may be some dimensional variation. The shape of the protrusion 32 is not limited to a cone, and may be a triangular pyramid, a quadrangular pyramid, a round pin shape, or the like. As shown in FIG. 2B, the planar layout of the protrusions 32 is preferably equidistant from each other (arranged at each vertex of an equilateral triangle). Thus, by arranging the protrusions 32 in a well-balanced manner, the planar accuracy of the optical component mounting surface can be increased.

  Usually, the optical pickup 100 is mounted on two shafts parallel to each other in the optical drive, and can slide in the radial direction of the optical disk by moving along the shafts. Therefore, the housing 11 includes a shaft insertion hole 34 into which one shaft is inserted, and a shaft fitting groove 35 to be fitted into the other shaft. The first and second shafts are parallel to the disk surface of the optical disk, and the bottom surface 36 of the housing is also set parallel to the disk surface. The bottom surface 36 of the housing is used as a reference surface for the mounting surface of each optical component. Since the bottom surface 36 of the housing is sufficiently wider than the mounting area of the optical component, even if there are some irregularities on the bottom surface 36 of the housing, the influence is very small, and the overall parallelism to the disk surface Is sufficiently secured. Therefore, the bottom surface 36 of the housing can be used as a reference surface for the optical component mounting surface.

  Next, as shown in FIGS. 3A to 3C, the housing 11 is set on the table 41 of the pressing device 40, and the pressing process of the protrusion 32 of the housing 11 is performed. The press device may be a hand press machine or a mechanical drive type press device. In the pressing process, the press head 42 is lowered straight to crush the tip of the protrusion 32 provided at the mounting position 31 of the optical component, thereby forming a plane parallel to the bottom surface (reference surface) 36 of the housing. Thereby, the heights of the protrusions having some height variation are made uniform, and the parallelism with respect to the reference surface is ensured with high accuracy.

  Thereafter, as shown in FIGS. 4A and 4B, the adhesive 43 is applied to the mounting position 31 of the optical component, and after mounting the optical component 30, the adhesive 43 is cured to thereby cure the optical component 30. Implementation of is complete.

  The amount of crushing of the protrusion 32 can be changed according to the size of the optical component 30 mounted thereon. When the height dimension of the optical component 30 is relatively large, the height of the protrusion may be lowered, and conversely, when it is small, the height of the protrusion may be increased.

  FIG. 5 is a schematic diagram for explaining a method of simultaneously forming a plurality of optical component mounting surfaces having different heights.

  In forming a plurality of optical component mounting surfaces having different heights, first, as shown in FIG. 5A, a housing 11 having mounting positions 31A and 31B for the first and second optical components is prepared. In the present embodiment, a plurality of protrusions 32A are formed at the mounting position 31A of the first optical component in the housing 11, and a plurality of protrusions 32B are formed at the mounting position 31B of the second optical component. . The size (height) of the protrusions 32A and 32B may be the same or different. On the other hand, a level difference d is provided on the press surface of the press head 42, and the height of the press surface suitable for each optical component is set.

  Next, a pressing process of the protrusions 32A and 32B of the housing 11 is performed. In the pressing step, the press head 42 is lowered straight to simultaneously crush the tips of the protrusions 32A and 32B provided at the mounting positions 31A and 31B of the optical components, and parallel to the bottom surface (reference surface) of the housing 11. A flat surface. Thereby, the height of the protrusion 32A is made uniform at the mounting position 31A of the first optical component, and the parallelism to the reference surface is ensured with high accuracy. Also, the height of the protrusion 32B is made uniform at the mounting position 31B of the second optical component, and the parallelism with respect to the reference surface is ensured with high accuracy. In particular, since a step d is formed on the press surface of the press head 42, and the amount of crushing of the protrusions 32A and 32B is made different from each other, even if all the protrusions are crushed simultaneously by this press head 42, mounting is possible. It is possible to form optical component mounting surfaces having different heights for each position.

  Thereafter, as in FIG. 4, after applying an adhesive to the mounting positions 31 </ b> A and 31 </ b> B of each optical component, the optical components 30 </ b> A and 30 </ b> B are mounted at predetermined mounting positions, and the adhesive is cured. Implementation of is complete. Thus, by making the heights of the optical component mounting surfaces different, the center position of each optical component can be made the same height as the optical axis OP.

  The optical component mounting surface does not have to be a plane parallel to the reference surface, and may be an inclined surface. For example, the mounting surface of the rising mirror 18 has a predetermined angle (for example, 40 degrees) with respect to the reference surface. Formation is possible.

  6 and 7 are schematic views for explaining a method of forming the rising mirror mounting surface.

  In forming the rising mirror mounting surface, as shown in FIG. 6, a housing 11 having four protrusions 32C provided at the mounting position 31C of the rising mirror is used. In the case of a rising mirror, a through-hole 11C that penetrates the bottom surface 36 of the housing is formed at the center of the mounting position 31C, and the mounting surface is divided into two parts. The protrusions 32C are formed two by two to balance the protrusions.

  Next, a pressing process of the protruding portion of the housing 11 is performed. In the pressing step, the press head is lowered straight to crush the tip of the protrusion 32C provided at the mounting position 31C of the rising mirror, and a plane having a predetermined angle with respect to the bottom surface (reference surface) 36 of the housing is formed. Form. As a result, the height of the protrusion 32C having a slight height variation is made uniform at the mounting position 31C of the rising mirror, and the parallelism with respect to the reference surface is ensured with high accuracy.

  Thereafter, as in FIG. 4, after applying an adhesive to the mounting position 31C of the rising mirror, mounting the rising mirror 30C at a predetermined mounting position and curing the adhesive, the mounting of the rising mirror is completed. To do.

  As described above, according to the present embodiment, a plurality of protrusions are formed at the mounting position of the optical component, and the tip of the protrusion is crushed to form a plane parallel to the reference surface. Since the height is adjusted, the flatness of the optical component mounting surface can be easily secured. Further, since no shavings are generated as in the case where the projection group is formed by cutting, it can be incorporated into the assembly line of the product. Therefore, it is possible to reduce the cost of the product and shorten the design / development period.

  As mentioned above, although this invention was demonstrated based on the preferable embodiment, this invention is not limited to the above embodiment, It is possible to add a various change within the range which does not deviate from the meaning of this invention, Needless to say, they are also included in the scope of the present invention.

  For example, in the above-described embodiment, a case where a metal housing formed by metal die casting is used as an example, but the present invention is not limited to a metal housing, but a resin housing. Is also applicable. As the resin material, for example, engineering plastics such as PPS (Poly-Phenyl Sulfide) can be used. When using resin, you may heat and press the front-end | tip part of a processus | protrusion, In this case, the process of heating processus | protrusion is required prior to a press process. Further, instead of directly heating the protrusions, the protrusions may be pressed using a preheated press head. As described above, even if the housing is made of resin, the same effect as that of die casting can be obtained, and when it is heated and pressed, it can be further easily processed.

FIG. 1 is a schematic perspective view showing an example of the configuration of an optical pickup. FIG. 2 is a diagram for explaining a method of forming the optical component mounting surface, and is a schematic diagram showing the structure of the housing 11. FIG. 3 is a diagram for explaining a method for forming an optical component mounting surface, and is a schematic diagram for explaining a pressing process of protrusions. FIG. 4 is a diagram for explaining a method for forming an optical component mounting surface, and is a schematic diagram showing an optical component bonding step. FIG. 5 is a schematic diagram for explaining a method of simultaneously forming a plurality of optical component mounting surfaces having different heights. FIG. 6 is a schematic diagram for explaining a method of forming the rising mirror mounting surface. FIG. 7 is a schematic diagram for explaining a method of forming the rising mirror mounting surface.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 Housing 11C Through-hole 12 Laser diode 13 Laser diode 14 Diffraction grating 16 Dichroic prism 17 Deflection beam splitter 18 Raising mirror 19 Sensor lens 20 Photodiode 21 Objective lens drive mechanism 22 Control circuit board 30C Raising mirror 30 Optical component 30A Optical component 30B Optical component 31 Optical component mounting position 31A Optical component mounting position 31B Optical component mounting position 31C Optical component (rising mirror) mounting position 32 Projection 32A Projection 32B Projection 32C Projection 34 Shaft insertion hole 35 Shaft fitting groove 36 Bottom 40 Press device 41 Table 42 Press head 43 Adhesive 100 Optical pickup OP Optical axis

Claims (6)

Providing a housing in which at least three protrusions are integrally formed for each mounting position of one optical component;
Forming a mounting surface of the optical component by crushing the tips of the at least three protrusions with a plane having a predetermined angle with respect to a predetermined reference surface. Forming method.   The method for forming an optical component mounting surface according to claim 1, wherein the predetermined reference surface is a bottom surface of the housing.   The housing has mounting positions for a plurality of optical components, and the at least three protrusions respectively provided at the mounting positions of the optical components are planes having different heights for the mounting positions of the optical components. The method for forming an optical component mounting surface according to claim 1 or 2, wherein the height of the mounting surface of the optical component is varied by crushing.   The method of forming an optical component mounting surface according to any one of claims 1 to 3, wherein the housing is molded by die casting.   The method of forming an optical component mounting surface according to any one of claims 1 to 3, wherein the housing is made of resin. Providing a housing in which at least three protrusions are integrally formed for each mounting position of one optical component;
Forming the mounting surface of the optical component by crushing the vertices of the at least three protrusions with a plane having a predetermined angle with respect to a predetermined reference surface;
A method of manufacturing an optical pickup, comprising a step of bonding an optical component corresponding to a mounting position of the optical component.

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