JP2014235764A - Optical pickup device, and method for manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an optical pickup device and the like capable of adjusting a position of a diffraction grating with a simple structure.SOLUTION: A diffraction grating 30 is stored in a storage region 13 in which a housing 12 is partially recessed. In the storage region 13, the diffraction grating 30 is supported at three points of a first contact portion 23, a second contact portion 25, and a third contact portion 27 which are a part of a resin portion of the housing 12. Thereby, the position of the diffraction grating 30 is fixed in a Dt direction in a state of being rotation-adjustable in the storage region 13.

Description

  The present invention relates to an optical pickup device including a diffraction grating and a light emitting element, and a manufacturing method thereof.

  With reference to FIG. 6, a configuration of a conventional optical pickup device 100 will be described. In the optical pickup device 100, a plurality of optical elements are housed in a housing 102 in which a resin material or the like is molded into a predetermined shape. On the upper surface of the housing 102, the substrate 104, the connector 106, and the actuator 108 that holds the objective lens 108 are arranged. The optical pickup device 100 irradiates the optical disk with laser light emitted from the light emitting element built in the housing 102 via the objective lens 110, and reads the laser light reflected on the optical disk with the light receiving element, thereby Is read or written (Patent Document 1).

  In the optical pickup device 100 described above, in order to perform tracking servo and focus servo, a diffraction grating is disposed in the vicinity of a light emitting element that emits laser light, and the laser light is separated into a plurality of diffracted lights by the diffraction grating. The

JP 2003-228866 A

  Conventionally, in order to adjust the position of the dividing line of the diffraction grating and the laser beam, the diffraction grating is translated after the position of the light emitting element is fixed, and then the diffraction grating is rotated and adjusted. Therefore, the position of the dividing line and the laser beam may be shifted after the rotation adjustment. In such a case, it is necessary to repeat the parallel movement and the rotation adjustment.

  Conventionally, in order to facilitate rotation adjustment and the like, the diffraction grating is built in a folder and stored in a housing, which causes an increase in the number of parts.

  The present invention has been made in view of such problems, and an object of the present invention is to provide an optical pickup device and a manufacturing method thereof in which the position of the diffraction grating can be adjusted with a simple structure.

  An optical pickup device of the present invention includes a housing, a light emitting element that is housed in the housing and emits laser light, a diffraction grating that separates the laser light emitted from the light emitting element into a predetermined order of diffracted light, The diffraction grating connects the first main surface on which the laser light is incident, the second main surface facing the first main surface, the first main surface and the second main surface, and the A first side and a second side opposite to each other in a thickness direction of the housing; a third side and a fourth side connecting the first main surface and the second main surface and opposing in the other direction; The housing includes a first contact portion that contacts a connection line between the second main surface and the third side surface of the diffraction grating, and a space between the second main surface and the fourth side surface of the diffraction grating. A second contact portion that contacts the connection line, and the first side surface or the first A third contact portion for contacting a side surface, and having a.

  The method of manufacturing an optical pickup device of the present invention includes a first step of incorporating a light emitting element that emits laser light into a housing, a first main surface on which the laser light is incident, and a second main surface that faces the first main surface. And connecting the first main surface and the second main surface to each other, and connecting the first main surface and the second main surface, and the first side surface and the second side surface facing each other in the thickness direction of the housing. A second step of incorporating, into the housing, a diffraction grating having a third side surface and a fourth side surface facing each other in the other direction and separating the laser light into predetermined diffracted light; and a second step of rotationally adjusting the diffraction grating. 3 steps, and in the second step, a connection line between the second main surface and the third side surface of the diffraction grating is brought into contact with the first contact portion of the housing, and the second main surface and the The connecting line with the fourth side is connected to the second contact portion of the housing. Contact is characterized by contacting said first side or said second side to the third contact portion of the housing.

  According to the optical pickup device of the present invention, the corner portion of the diffraction grating is supported by the first contact portion and the second contact portion of the housing, and the side surface of the diffraction grating is supported by the third contact portion. Therefore, the diffraction grating is temporarily fixed to the housing so as to be rotatable at these contact portions, and subsequent rotation adjustment becomes easy. Furthermore, since the diffraction grating is directly fixed to the housing, a dedicated folder for providing the diffraction grating in the housing is not required, and the number of parts required for the optical pickup device is reduced.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows the optical pick-up apparatus of this invention, (A) is a perspective view which shows the optical pick-up apparatus which made the upper surface the side which an objective lens exposes, (B) is the optical pick-up apparatus of the state turned upside down It is a perspective view shown. It is a figure which shows the optical system integrated in the optical pick-up apparatus of this invention. It is a figure which shows the optical pick-up apparatus of this invention, (A) is a perspective view which shows the housing of the part in which a diffraction grating is integrated, (B) is sectional drawing which looked at this part in Dr direction, (C ) Is a view of this portion when viewed in the Df direction. It is a figure which shows the optical pick-up apparatus of this invention, (A) is a perspective view which shows the structure where the fixing plate which supports a light emitting element is provided in a housing, (B) is an enlarged view of the part with which a fixing plate is provided. It is a perspective view shown, (C) is a sectional view of this part. 3 is a flowchart showing a method for manufacturing the optical pickup device of the present invention. It is a perspective view which shows the optical pick-up apparatus of background art.

  With reference to FIG. 1, the optical pick-up apparatus 10 of this form is demonstrated. FIG. 1A is a perspective view showing the optical pickup device 10 when the surface from which the objective lens is exposed is the upper surface, and FIG. 1B is an optical pickup device in which the state of FIG. FIG.

  In this embodiment, description will be made using each direction of Dt, Dr, and Df. The Dt direction is the tangential direction, the Dr direction is the radial direction, the Df direction is the focus direction, and these directions are orthogonal to each other.

  Referring to FIG. 1, an optical pickup device 10 focuses laser light of DVD (Digital Versatile Disk) and CD (Compact Disk) standards on an information recording layer of an optical disk (information recording medium) of a corresponding standard, It has a function of receiving reflected light from the information recording layer and converting it into an electrical signal. Thereby, reading of information from the optical disk and writing of information to the optical disk are performed. Here, the optical pickup device 10 does not necessarily correspond to the laser light of these two types of standards. In addition to these, it may be compatible with BD (Blu-ray (registered trademark) Disc) standard laser light, or only one of these standards.

  The optical pickup device 10 includes a housing 12 and various optical elements incorporated in the housing 12. The housing 12 incorporates an actuator 18 that holds the objective lens 26 so as to be movable.

  The housing 12 is made of a resin material that is integrally formed by injection molding, and has a storage area inside which can store optical elements and electronic components. As a resin material constituting the housing 12, polycarbonate, modified PPE, ABS, PPS resin or the like is employed. A part of the housing 12 is provided with a curved portion in an area where the turntable is close. And the guide hole 14 and the guide groove 16 are provided in the both ends so that this curved part may be pinched | interposed. Under use conditions, a guide shaft is inserted into the guide hole 14, and another guide shaft is engaged with the guide groove 16. The optical pickup device 10 moves along these guide axes. In this embodiment, the housing 12 is composed of an injection molded resin housing portion and a metal plate incorporated in the resin housing portion.

  Referring to FIG. 1A, the upper surface of the housing 12 from which the objective lens 26 is exposed is mostly covered with the cover 11. The cover 11 is formed by bending a metal plate having a thickness of about 0.1 mm into a predetermined shape, and its periphery is fitted to a convex portion provided on the side surface of the housing 12. The cover 11 is coupled to the housing 12 via a screw 31 that passes through the hole. On the other hand, a region on the upper surface of the housing 12 where the objective lens 26 is exposed is not covered with the cover 11 in order to enable laser light irradiation. Specifically, the actuator 18 that holds the objective lens 26 in a predetermined position elastically supports the holder 24 via a plurality of support wires 22 and a box-shaped holder 24 that holds the objective lens 26. It is comprised from the support part 20. FIG.

  In this embodiment, a fixing plate 15 is incorporated in the housing 12, and this fixing plate 15 is for fixing a light emitting element (not shown). Here, since the upper surface of the housing 12 is covered with the cover 11, it is not visually recognized, and a region where the fixing plate 15 is disposed is indicated by a dotted line. Further, a storage area 13 for storing the diffraction grating is disposed in the vicinity of the fixing plate 15.

  Referring to FIG. 1B, the housing 12 of the optical pickup device includes a resin housing portion 48 that occupies most of the housing and a metal plate 50 that constitutes a part of the bottom portion. Further, guide grooves 16 and guide holes 14 are provided at both left and right end portions of the housing 12 on the paper surface, and these are also configured as a part of the resin housing portion 48. Further, a wiring sheet 29 electrically connected to the optical element built in the housing 12 is led out to the outside.

  Here, the storage region 13 is a region where the resin housing portion 48 of the housing 12 is recessed from the −Df side, and the diffraction grating is stored in this region. This matter will be described later with reference to FIG.

  With reference to FIG. 2, the optical element built in the optical pick-up apparatus 10 is demonstrated. The optical pickup device 10 includes a light emitting element 28, a diffraction grating 30, a half mirror 32, a collimator lens 38, a rising mirror 40, a quarter wavelength plate 36, an AS plate 42, a PDIC 44, and an FMD 34. The main features.

  The light emitting element 28 incorporates one or a plurality of laser chips, and emits the laser light of each standard described above from the light emitting point of the laser chip.

  The diffraction grating 30 separates each laser beam emitted from the light emitting element 28 into 0th order diffracted light, + 1st order diffracted light, and −1st order diffracted light.

  The half mirror 32 reflects the forward laser light emitted from the light emitting element 28 and passing through the diffraction grating 30 and the like, and transmits the backward laser light (return light) reflected by the optical disk.

  The quarter-wave plate 36 has an action of converting the laser light reflected by the half mirror 32 from linearly polarized light to circularly polarized light, and conversely, the return light reflected by the optical disk is linearly polarized from the circularly polarized light. Convert to light.

  The collimator lens 38 converts the laser light reflected by the half mirror 32 into parallel light.

  The raising mirror 40 has a function of reflecting the laser light transmitted through the collimator lens 38 toward the objective lens.

  The PDIC 44 detects laser light of each standard and is used for focus servo and tracking servo.

  An FMD 34 (front monitor diode) detects laser light emitted from the light emitting element 28 and transmitted through the half mirror 32.

  An LDD 46 (laser diode driver) receives the output of the FMD 34 and adjusts the intensity of the laser light emitted from the light emitting element 28.

  The AS plate 42 gives aberration to the return laser beam that passes through the half mirror 32.

  Next, a read operation and a write operation of the optical pickup device 10 configured as described above will be described. The optical path of the laser beam used for reading and writing of each standard is the same as follows.

  First, the laser light emitted from the light emitting element 28 is separated into 0th-order diffracted light, + 1st-order diffracted light, and −1st-order diffracted light by passing through the diffraction grating 30. This is because servo is performed using the PDIC 44. The laser light that has passed through the diffraction grating 30 is reflected by the half mirror 32, and then the laser light is converted into circularly polarized light by the quarter wavelength plate 36, and then converted into parallel light by the collimator lens 38, The light is reflected by the rising mirror 40 and travels in the direction perpendicular to the optical disk. After that, the signal recording surface of the optical disk is focused by the refraction or diffraction action of an objective lens (not shown).

  The laser light (returned light) reflected by the signal recording surface of the disc passes through the quarter wavelength plate 36 through the objective lens, the rising mirror 40, and the collimator lens 38, so that a straight line having a polarization direction different from that of the forward path. Converted to polarized light. Specifically, the direction of polarization is reversed when the laser light converted into circularly polarized light in the forward path is reflected by the information recording layer of the disk, and the circularly polarized light in this state passes through the quarter wavelength plate 36 in the backward path. Thus, the polarization direction is converted by using the linearly polarized light. Next, the laser light that has become the linearly polarized light passes through the half mirror 32 and passes through the AS plate 42, and after being given and corrected for aberrations, is irradiated onto the light receiving surface of the PDIC 44. The PDIC 44 reads information and outputs signals for focus servo and tracking servo.

  Further, a part of the forward laser light emitted from the light emitting element 28 passes through the half mirror 32 and is irradiated to the FMD 34. The LDD 46 adjusts the laser light emitted from the light emitting element 28 to have a predetermined intensity based on the intensity of the laser light irradiated on the FMD 34.

  The above is the description of the optical configuration and operation of the optical pickup device 10.

  A structure in which the diffraction grating 30 is housed in the housing 12 will be described with reference to FIG. 3A is a perspective view showing the storage region 13 in which the diffraction grating 30 is stored, FIG. 3B is a cross-sectional view of this part in the Dr direction, and FIG. 3C is this part. It is sectional drawing which looked at Df direction.

  Referring to FIG. 3A, the diffraction grating 30 is housed in the housing region 13 and its position is fixed. The storage area 13 is a concave portion in which the housing 12 is recessed in the Df direction, and the size thereof is slightly larger than the diffraction grating 30 to be stored. The storage region 13 has a substantially cross shape extending in both the Dt direction and the Dr direction in plan view. The reason why the storage region 13 has such a substantially cross shape is that after the diffraction grating 30 is stored in the storage region 13, it is necessary to move and adjust the diffraction grating 30 with respect to the rotation direction. This is to ensure a space for insertion. Further, in order to ensure the optical path of the laser light emitted from the light emitting element 28, the side surface of the storage region 13 facing the + Dr direction and the -Dr direction is opened.

  Here, the diffraction grating 30 is made of a translucent material such as glass, and has a main surface facing the + Dr direction, a main surface facing the -Dr direction, and four side surfaces connecting these main surfaces. That is, the diffraction grating 30 generally has a hexahedral structure. In addition, a diffractive structure is provided on the main surface on the -Dr side or the main surface on the + Dr side. Further, on the main surface on the −Dr side of the diffraction grating 30, a dividing line 30 </ b> A that is a boundary between the −Dt side diffraction structure and the + Dt side diffraction structure is provided substantially parallel to the Df direction.

  Referring to FIGS. 3B and 3C, the diffraction grating 30 housed in the housing region 13 described above includes a first contact portion 23 and a second contact portion that are part of the resin portion of the housing 12. 25 and the third contact portion 27 are supported at three points. Thereby, the position of the diffraction grating 30 is fixed in the Dt direction in a state in which the rotation can be adjusted inside the storage region 13.

  The structure of these contact parts will be described. The first contact part 23 and the second contact part 25 are parts for positioning the diffraction grating 30 in the Dt direction. The first contact portion 23 contacts a connection line between the −Dr side main surface and the −Dt side surface of the diffraction grating 30. Specifically, the inclined surface provided at the tip of the first contact portion 23 is in contact with a connection line between the −Dr side main surface and the −Dt side surface of the diffraction grating 30. On the other hand, the second contact portion 25 is in contact with the connection line between the −Dr side main surface and the + Dt side surface of the diffraction grating. Also here, the inclined surface provided at the tip of the second contact portion 25 is in contact with this connection line. In this way, the first contact portion 23 and the second contact portion 25 are in contact with the connection line (corner portion) of the diffraction grating 30, the position of the diffraction grating 30 is fixed in the Dt direction, and a diffraction grating described later. 30 rotation adjustments are possible.

  Furthermore, the first contact portion 23 and the second contact portion 25 are in contact with the diffraction grating 30 in the portion including the center of each connection line, and thereby the diffraction in a state of being temporarily fixed at each contact portion. Even if the grating 30 is rotated, the center position of the diffraction grating 30 is hardly displaced. Therefore, even if the diffraction grating 30 is rotationally adjusted, the positions of the dividing line 30A and the laser beam are basically not shifted. In this case, the laser beam may be irradiated near the center of the dividing line 30A.

  Further, in the manufacturing process, a hard diffraction grating 30 made of glass is pressed into the storage area 13. Thereby, referring to FIG. 3C, the corners of diffraction grating 30 bite into the inclined portions provided at the tips of first contact portion 23 and second contact portion 25. Therefore, due to this biting action, a depressing force is generated that pushes the diffraction grating 30 to the + Dr side, and the vicinity of both ends of the main surface of the diffraction grating 30 on the + Dr side comes into contact with the abutting portion 33 of the housing. As a result, the diffraction grating 30 is positioned in the Dr direction.

  In addition, referring to FIG. 3B, the tip portions of first contact portion 23 and second contact portion 25 that contact diffraction grating 30 are formed to be narrower than the intermediate portion. As a result, the first contact portion 23 and the second contact portion 25 substantially support the diffraction grating 30 at points, and the diffraction grating 30 is rotationally adjusted after the diffraction grating 30 is sandwiched between these support portions. Is possible.

  With reference to FIG. 3B, the third contact portion 27 is a portion that contacts the side surface of the diffraction grating 30 on the −Df side, and thereby determines the position of the diffraction grating 30 in the Df direction. Further, the third contact portion 27 is in contact with the center of the diffraction grating 30 in the Dt direction, and can thereby support the diffraction grating 30 with a good balance. The cross section of the upper end of the third contact portion 27 has a shape (for example, a semicircular shape) that is curved so as to protrude upward. That is, the third contact portion 27 has a so-called kamaboko shape. As a result, the portion where the third contact portion 27 contacts the lower surface of the diffraction grating 30 becomes a line extending in the Dr direction, which is a line contact. Accordingly, the diffraction grating 30 can be rotated and adjusted after the diffraction grating 30 is brought into contact with the third contact portion 27. Here, if the upper end of the third contact portion 27 is entirely flat and the contact between the third contact portion 27 and the diffraction grating 30 is a surface contact, the diffraction grating 30 is brought into contact with the third contact portion 27. It is not easy to adjust the rotation of the diffraction grating 30 after the adjustment. In an actual product, the diffraction grating 30 is fixed to the housing 12 via an adhesive.

  With reference to FIG. 4, a structure in which the light emitting element is incorporated in the housing will be described. 4A is a perspective view illustrating a configuration in which the fixing plate 15 supporting the light emitting element is provided in the housing 12, and FIG. 4B is a perspective view illustrating an enlarged portion in which the fixing plate 15 is provided, FIG. 4C is a cross-sectional view of the same portion facing the Dr direction.

  Referring to FIG. 4A, the housing 12 has a storage area formed of a bottom surface and a side wall portion, and various optical elements are fixed to the storage area surrounded by the bottom surface and the side wall portion, so that each element is The relative positions of each other are fixed. This storage area is open in the -Df direction, and an optical element such as a half mirror is incorporated from this open side.

  In this embodiment, the fixing plate 15 is fixed to one of the storage areas, and the light emitting element 28 is fixed to the housing 12 via the fixing plate 15. Further, the storage area 13 in which the diffraction grating 30 shown in FIG. 4 is stored is disposed in the immediate vicinity of the fixing plate 15.

  Referring to FIG. 4B, first, the fixing plate 15 is a plate-like member made of a metal material such as aluminum and is housed in the housing area of the housing 12. By employing a metal as the material of the fixing plate 15, heat generated by the mounted light emitting element during operation can be released to the outside through the fixing plate 15.

  Here, the storage area for the fixing plate 15 is formed slightly larger than the fixing plate 15 in the Dt direction. Thus, after the fixing plate 15 is assembled in the housing 12, the fixing plate 15 can be moved for adjustment in the Dt direction. Here, in the state of being incorporated in the housing 12, the main surface of the fixing plate 15 is substantially perpendicular to the dividing line 30 </ b> A of the diffraction grating 30.

  The light emitting element 28 is fixed to the main surface on the + Df side of the fixing plate 15 via an adhesive or the like. The light emitting element 28 is obtained by packaging the light emitting chip 41 in a resin package, and is fixed to the fixing plate 15 so that the surface on which the light emitting chip 41 is exposed faces the diffraction grating 30 side. In addition, a plurality of leads 43 electrically connected to the respective electrodes of the light emitting chip 41 are led out from the notch part of the housing 12 where a part of the outer side wall part is omitted. In the present embodiment, the light source of the light emitting chip 41 that emits laser light is moved along the Dt direction to align the dividing line of the diffraction grating 30 with the laser light. This is done by moving the fixing plate 15.

  The fixing plate 15 is provided with two through holes 37A and 37B so as to sandwich the light emitting element 28 in the Dt direction. The through hole 37A is provided through the fixing plate 15 on the + Dt side with respect to the light emitting element 28, and is formed to be elongated along the Dt direction. Similarly, the through hole 37B is provided so as to penetrate through the fixing plate 15 on the −Dt side with respect to the light emitting element 28, and is formed elongated along the Dt direction. The reason why the through holes 37A and 37B are formed to be elongated along the Dt direction is that the light emitting element 28 fixed to the fixing plate 15 is moved along the Dt direction after the fixing plate 15 is assembled into the housing 12. It is.

  A protruding portion 35A in which the resin portion of the housing 12 is protruded in the Df direction is inserted into the through hole 37A of the fixing plate 15. The size of the projection 35A in the Dr direction is substantially the same as that of the through hole 37A, and the size of the projection 35A in the Dt direction is smaller than that of the through hole 37A. Therefore, when the protrusion 35A having such a size is passed through the through hole 37A, the fixing plate 15 is fixed to the housing 12 in the Dr direction and is movable in the Dt direction.

  Similarly, a protrusion 35B is inserted into the through hole 37B of the fixing plate 15. The protrusion 35B has the same size as the through hole 37B in the Dr direction, and the protrusion 35B is smaller than the through hole 37B in the Dt direction. Accordingly, the fixing plate 15 is fixed in the Dr direction with respect to the housing 12 and is movable in the Dt direction.

  Here, the protrusion 35A has a circular shape in plan view, while the protrusion 35B is formed to be elongated along the Dt direction. When the protrusion 35B is long and thin, the position of the fixing plate 15 in plan view can be more firmly fixed. In an actual product, the fixing plate 15 is fixed to the housing 12 via an adhesive.

  Referring to FIG. 4C, two main surface support portions 39A and 39B are provided by protruding a part of the bottom surface portion of the housing 12 in the + Df direction, and the upper surfaces of these portions are flat at the same level. A surface is formed. The vicinity of both end portions in the Dt direction on the lower surface of the fixing plate 15 is in contact with the main surface support portions 39A and 39B. The position of the light emitting element 28 fixed to the lower surface of the fixing plate 15 in the Df direction is fixed by this contact.

  With reference to the flowchart of FIG. 5 and each of the above-described drawings, a method of manufacturing the optical pickup device 10 having the above-described configuration will be described focusing on the alignment of the light emitting element and the diffraction grating.

  First, referring to FIG. 3, the diffraction grating 30 is incorporated in the storage region 13 of the housing 12 (step S10). Specifically, the diffraction grating 30 having a substantially hexahedral shape is inserted into the diffraction grating 30 from the + Df side. Here, when the diffraction grating 30 is inserted into the storage region 13, as shown in FIG. 3C, the corners of the diffraction grating 30 are at the distal ends of the first contact portion 23 and the second contact portion 25. Cut into the formed inclined surface. Thereby, the diffraction grating is fixed in the Dt direction. In addition, a + Dr direction instability is thereby generated, and both ends of the main surface on the Dr side of the diffraction grating 30 come into contact with the contact portion 33. Therefore, the diffraction grating 30 is fixed with respect to the Dr direction. 3B, the diffraction grating 30 is pushed into the storage region 13 until the −Df side surface of the diffraction grating 30 comes into contact with the third contact portion 27. Thereby, the diffraction grating 30 is fixed with respect to the Df direction. Here, the fixing of the diffraction grating 30 in this step is not strong, and is a temporary fixing to allow a later rotation adjustment.

  Next, with reference to FIG. 4, a light emitting element is assembled in the housing 12 (step S11). As described above, the light-emitting element 28 in which the light-emitting chip 41 is packaged in a resin package is prepared in a state of being fixed to the fixing plate 15 with an adhesive. Here, the fixing plate 15 having the light emitting element 28 on the lower surface is housed in the arrangement region of the housing 12. Then, the projections 35A and 35B, in which the resin portion of the housing 12 is projected, are inserted into the through holes 37A and 37B of the fixing plate 15. Thereby, the fixing plate 15 having the light emitting element 28 is temporarily fixed to the housing 12 in a state of being movable in the Dt direction.

  Next, referring to FIG. 4B, the laser beam and the diffraction grating are aligned (step S12). Specifically, first, a predetermined laser beam is emitted from the light emitting chip 41 without moving the diffraction grating 30 disposed in the storage region 13. When the light emitting chip 41 emits laser light of DVD standard and CD standard, laser light of any standard is emitted. Next, the position of the fixing plate 15 is adjusted while confirming with a monitor the diffracted light emitted from the light emitting chip 41 and separated by the diffraction grating 30. Specifically, the fixing plate 15 is moved in the Dt direction so that the emitted laser light is superimposed on the dividing line 30 </ b> A of the diffraction grating 30 or is arranged in the nearest position. Here, when the light emitting chip 41 has two light emitting sources that emit laser light of the DVD standard and the CD standard, when the diffraction grating 30 is viewed in the Dr direction, the diffraction grating 30 is intermediate between the two light emitting sources. The dividing line 30A is arranged. Preferably, the DVD standard laser light source is closer to the dividing line 30A than the CD standard laser light source. Thereby, the balance of the diffracted light becomes more uniform with the DVD standard laser light. After this adjustment is completed, the fixing plate 15 may be fixed to the housing 12 using an adhesive.

  Next, referring to FIG. 3, the rotation of the diffraction grating 30 is adjusted. Specifically, the diffraction grating 30 is rotated so that the 0th-order light, the + 1st-order light, and the −1st-order light emitted from the light emitting element 28 and diffracted by the diffraction grating 30 are aligned in the normal direction of the optical disk. The applied adjustment is particularly important when the inline DPP method is adopted as the servo method. Referring to FIG. 3A, rotation adjustment of the diffraction grating 30 is performed by inserting an adjustment jig into the storage region 13 and holding the diffraction grating 30 from both sides in the Dt direction with this jig. Referring to FIG. 3B, the diffraction grating 30 is temporarily fixed by the first contact portion 23, the second contact portion 25, and the third contact portion 27 and is in a rotatable state. Therefore, it is possible to adjust the rotation with a jig that sandwiches the diffraction grating 30. Further, since this rotation is a slight one degree or less, by performing this rotation adjustment, the position of the dividing line 30A does not fluctuate greatly, and the position adjustment in the Dt direction is not required again. .

  Through the above steps, the position adjustment between the light emitting element 28 and the diffraction grating 30 is completed. After this adjustment is completed, an adhesive is also applied between the diffraction grating 30 and the housing 12 to fix them together. Thereafter, the optical pickup device 10 shown in FIG. 1 is completed through a process of accommodating other optical elements in the housing 12, an adjustment process, and the like.

  The above-described embodiment can be modified as follows, for example.

  Referring to FIG. 3B, the upper end portion of the third contact portion 27 has a curved shape, but may have another shape protruding upward (for example, a shape protruding at an obtuse angle or an acute angle).

  Referring to FIG. 3A, in the above embodiment, the diffraction grating 30 is directly fixed to the housing 12. However, the diffraction grating 30 may be prepared in a folder and the folder may be fixed to the housing 12. .

  With reference to FIG. 4, in the above embodiment, the light emitting element 28 is fixed to the housing 12 via the fixing plate 15, but the light emitting element 28 may be directly fixed to the housing 12.

  Referring to the flowchart of FIG. 5, in the above embodiment, the rotation adjustment of the diffraction grating is performed after the alignment of the laser beam and the diffraction grating, but this order may be reversed.

DESCRIPTION OF SYMBOLS 10 Optical pick-up apparatus 11 Cover 12 Housing 13 Storage area 14 Guide hole 15 Fixing plate 16 Guide groove 18 Actuator 20 Support part 22 Support wire 23 First contact part 24 Holder 25 Second contact part 26 Objective lens 27 Third contact part 28 Light emission Element 29 Wiring sheet 30 Diffraction grating 30A Dividing line 31 Screw 32 Half mirror 33 Contact part 34 FMD
35A, 35B Projection part 36 1/4 wavelength plate 37A, 37B Through-hole 38 Collimator lens 39A, 39B Main surface support part 40 Rising mirror 41 Light emitting chip 42 AS board 43 Lead 44 PDIC
46 LDD
48 Resin housing part 50 Metal plate 52 Protrusion part 54 Through hole

Claims (6)

A housing;
A light emitting element that is housed in the housing and emits laser light;
A diffraction grating that separates the laser light emitted from the light emitting element into diffracted light of a predetermined order,
The diffraction grating connects the first main surface on which the laser light is incident, the second main surface facing the first main surface, the first main surface and the second main surface, and the thickness of the housing. A first side and a second side facing each other in a direction, and a third side and a fourth side connecting the first main surface and the second main surface and facing each other in the other direction,
The housing includes a first contact portion that contacts a connection line between the second main surface and the third side surface of the diffraction grating, and a space between the second main surface and the fourth side surface of the diffraction grating. An optical pickup device comprising: a second contact portion that contacts the connection line; and a third contact portion that contacts the first side surface or the second side surface.   The optical pickup device according to claim 1, wherein corner portions of the diffraction grating are press-fitted into the first contact portion and the second contact portion.   3. The optical pickup device according to claim 1, wherein a portion of the third contact portion that contacts the diffraction grating has a curved surface shape in a cross-sectional view. The tip of the first contact portion that contacts the diffraction grating is thinner than the middle portion thereof,
4. The optical pickup device according to claim 1, wherein a tip end portion of the second contact portion that contacts the diffraction grating is narrower than an intermediate portion thereof. 5. A first step of incorporating a light emitting element for emitting laser light into the housing;
The first main surface on which the laser beam is incident, the second main surface facing the first main surface, the first main surface and the second main surface are connected, and the first main surface is opposed in the thickness direction of the housing. A first side surface and a second side surface; and a third side surface and a fourth side surface that connect the first main surface and the second main surface and face each other in the other direction, and convert the laser light into predetermined diffracted light. A second step of incorporating a separating diffraction grating into the housing;
A third step of rotationally adjusting the diffraction grating,
In the second step, a connection line between the second main surface and the third side surface of the diffraction grating is brought into contact with a first contact portion of the housing, and a connection line between the second main surface and the fourth side surface In contact with the second contact portion of the housing, and the first side surface or the second side surface is brought into contact with the third contact portion of the housing. 6. The method of manufacturing an optical pickup device according to claim 5, wherein, in the second step, a corner portion of the diffraction grating is caused to bite into the first contact portion and the second contact portion.

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