JP4008382B2 - Manufacturing method of optical head device and optical head device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an optical recording medium such as a CD (compact disc) or a DVD (digital versatile disc) by using a single light source having a plurality of light emitting elements and a single light receiver having a plurality of light receiving elements. The present invention relates to an optical head device for reproducing and recording information.
[0002]
[Prior art]
In an optical head device, a laser beam emitted from a light source is converged on an optical recording medium such as a CD or a DVD via an objective lens, and return light reflected by the optical recording medium is received by a light receiver. Information is played back and recorded.
[0003]
Here, in order to accurately receive the return light reflected by the optical recording medium with the light receiver, it is necessary to adjust the position when the light receiver is mounted on the apparatus frame. Therefore, the position of the light receiver is adjusted by moving it in the X and Y directions on the mounting surface of the apparatus frame (see, for example, Patent Document 1). Further, the position of the light receiver is adjusted in the optical axis direction (Z direction) of the return light (see, for example, Patent Document 2).
[0004]
Further, in an optical head device capable of both CD reproduction and DVD reproduction, a single laser light source that emits laser beams having two different wavelengths for CD reproduction and DVD reproduction is used to read from an optical recording medium. There is a type in which a plurality of return lights are received by a single light receiver.
[0005]
For example, as shown in FIG. 6A, such an optical head device includes a first laser diode chip 101 that emits a first laser beam L1 and a second laser that emits a second laser beam L2. While the two-wavelength laser light source 103, the light receiver 104, and the first laser light L1 and the second laser light L2 that are housed adjacent to each other in one package are guided to the optical recording medium 105, The first and second laser beams L 1 and L 2 have a common optical system 106 that guides the first and second return beams LR 1 and LR 2 reflected by the optical recording medium to the light receiver 104. The common optical system 106 diffracts the first laser beam L1 into three beams and transmits the second laser beam L2, and the first and second laser beams L1 and L2 to the optical recording medium 105. The half mirror 108 that is reflected toward the collimator, the collimator lens 109 that makes the first and second laser beams L1 and L2 reflected by the half mirror 108 parallel light, and the first and first laser beams that are collimated by the collimator lens 109. And an objective lens 110 that converges the two laser beams L1 and L2 onto the optical recording medium 105. The common optical system 106 includes first and second return beams LR1 and LR2 obtained by reflecting the first laser beam and the second laser beam on the optical recording medium 105, the objective lens 110, the collimator lens 109, and the half-lens. The light is guided to the light receiver 104 through the mirror 108.
[0006]
Here, since the first and second laser diode chips 101 and 102 are arranged at a predetermined interval, the first and second return lights LR1 and LR2 are also received at a predetermined interval. Led to. Therefore, in the light receiver 104, the first and second light receiving elements 141 and 142 for receiving the first and second return lights LR1 and LR2 are arranged at a predetermined interval. In the first light receiving element 141, since the first return light LR1 is divided into three beams in order to perform tracking error correction, as shown in FIG. 6B, three light receiving regions 141a and 141b are provided. 141c.
[0007]
Also for such a light receiver 104, when the light receiver 104 is mounted on the apparatus frame, the position of the light receiver 104 is adjusted in the X direction and the Y direction, and further in the Z direction, so that the first and second return lights are obtained. LR1 and LR2 can be accurately received by the first and second light receiving elements 141 and 142.
[0008]
[Patent Document 1]
Japanese Patent Laid-Open No. 7-240035 (page 3-5, FIG. 1)
[Patent Document 2]
Japanese Patent Publication No. 5-55932 (page 2-3, FIG. 1)
[0009]
[Problems to be solved by the invention]
Here, for example, as shown in FIG. 6C, the two-wavelength laser light source 103 is attached to the apparatus frame using a pair of attachment references S formed at opposite positions of the exterior. However, in the case where the angular positions of the first and second laser diode chips 101 and 102 are obliquely shifted from the mounting reference S in the two-wavelength laser light source 103, or when the positioning accuracy of the half mirror 108 is poor, The positions of the return lights LR1 and LR2 received by the light receiver 104 are also obliquely shifted, and such inclination causes the light receiver 104 to be biaxial (X and Y directions) and optical axis (Z direction). It cannot be resolved simply by moving to. Therefore, if the light receiver 104 is rotated around the optical axis to eliminate the inclination (shift in angular position), the folding angle and the positions of the adjusted light receiving elements 141 and 142 are shifted.
[0010]
Therefore, conventionally, a diffraction grating 111 is arranged between the light receiver 104 and the half mirror 108 in order to correct the inclination of the return lights LR1 and LR2. However, when such a countermeasure is adopted, diffraction is performed. There are problems in that the position adjustment of the lattice 111 takes considerable time and the cost increases as the number of parts increases.
[0011]
In view of the above problems, an object of the present invention is to adjust the inclination of a single light receiver having a plurality of light receiving elements that receive each laser beam emitted from a single light source having a plurality of light emitting elements. It is an object of the present invention to provide an optical head device manufacturing method and an optical head device capable of easily performing the above.
[0012]
[Means for Solving the Problems]
In order to solve the above problems, in the present invention, a first light emitting element that emits a first laser beam, and a first laser beam having a wavelength different from that of the first laser beam at a position adjacent to the first light emitting element. A light source including a second light emitting element that emits the second laser light, a first light receiving element that receives the first return light reflected by the optical recording medium, and the second light receiving element. A light receiver including a second light receiving element that receives second return light reflected by the optical recording medium at a position adjacent to the first light receiving element, and the light source and the light receiver. In the method of manufacturing the optical head device having the device frame, the optical axis of one of the first return light and the second return light is adjusted in the step of adjusting the position of the light receiver. , Of the first light receiving element and the second light receiving element Align the position with the one light receiving element that receives the one return light, and in this state, rotate the light receiver around the axis passing through the one light receiving element to receive the other light on the optical axis of the other return light. The position of the element is matched.
[0013]
In the present invention, in a state where the optical axis of one return light and the position of one light receiving element are aligned, the photoreceiver is rotated around the axis passing through one light receiving element, and the other return light is aligned with the optical axis of the other return light. Since the positions of the light receiving elements are matched, the angular positions (tilts) of the two light receiving elements can be adjusted according to the angular positions of the two return lights, and there is no need to correct the tilt using a diffraction grating. Therefore, laborious adjustment work of the diffraction grating can be omitted and the number of parts can be reduced. In addition, since the light receiver is rotated around the axis passing through one light receiving element with the position of the one light receiving element aligned with the optical axis of one return light, the folding angle and position adjustment are performed when the light receiver is rotated. The position of the one light receiving element with respect to the optical axis of the one return light that has been performed is not shifted. Therefore, the angular positions of the two light receiving elements can be easily adjusted according to the inclinations of the two return lights.
[0014]
  In the present invention, the light receiver is mounted on the device frame in a state of being fixed to a fixing member having a larger outer dimension than the light receiver, and the fixing member is the center of the outer shape when viewed from the optical axis side. Matches the position of the one light receiving elementAnd a rotational center position defining the rotational center axis when the light receiver is rotated around the optical axis on the opposite side surface of the fixed member located across the one light receiving element, at a position passing through the one light receiving element. And has a rectangular shape with four corners cut away or a circular outer shape when viewed from the optical axis direction.In the step of adjusting the position of the photoreceiver, the fixing member is held by the rotation center position defining portion, and the photoreceiver is rotated around an axis passing through the one light receiving element.It is like that.If comprised in this way, even if it does not hold | maintain a small light receiver, it can hold | maintain and rotate a big fixing member, Therefore An adjustment of an angular position can be performed easily. In addition, the fixing member includes a rotation center position defining portion whose center of the outer shape coincides with the position of one of the light receiving elements. Therefore, the fixing member is held by the rotation center position defining portion with a jig or the like. Can be rotated around the axis passing through one of the light receiving elements. Therefore, the angular positions of the two light receiving elements can be easily adjusted according to the inclinations of the two return lights.
[0015]
In the present invention, a first light emitting element that emits a first laser light, and a second laser light that emits a second laser light having a wavelength different from that of the first laser light at a position adjacent to the first light emitting element. A light source including the light emitting element, a first light receiving element that receives the first return light reflected by the optical recording medium, and the second laser light is the optical recording medium. An optical head having a light receiver including a second light receiving element that receives reflected second return light at a position adjacent to the first light receiving element, and a device frame on which the light source and the light receiver are mounted. In the apparatus, for the light receiver, a rotation center axis when rotating the light receiver around the optical axis is set to one of the first light receiving element and the second light receiving element. The rotation center position defining means for defining the passing position is Made is characterized in that is.
[0016]
  Also,The light receiver is mounted on the apparatus frame in a state of being fixed to a fixing member having a larger outer dimension than the light receiver, and the fixing member has the center of the outer shape when viewed from the optical axis side. Matches the position of the light receiving elementThe rotation center axis when rotating the light receiver around the optical axis on the opposite side surface of the fixing member located across the one light receiving element is defined as a position passing through the one light receiving element.The rotation center position defining meansIt has.
[0017]
  further,The fixing member has a shape in which four corners of a rectangle are cut off or a circular outer shape when viewed from the optical axis direction.Have.If comprised in this way, since the circumscribed circle with respect to a fixing member will become small, the area | region required in order to rotate a fixing member may be small. Therefore, the operation of rotating the fixing member can be easily performed, and the fixing member can be rotated over a wide angle range.
[0018]
In the present invention, the second laser beam has a wavelength shorter than that of the first laser beam, and the rotation center axis when rotating the light receiver around the optical axis passes through the second light receiving element. Preferably it is. The second laser beam having a short wavelength is used for recording and reproducing information on an optical recording medium having a high recording density, and accordingly, the second light receiving element is required to have high positional accuracy. Therefore, if the second light receiving element is preferentially positioned, high positional accuracy can be obtained, so that information recording and reproduction on an optical recording medium having a high recording density can be performed accurately.
[0019]
In the present invention, the first laser light is divided into a main beam and sub beams on both sides of the main beam, while the first light receiving element is a main light receiving region for detecting the main beam. And a sub light receiving area for detecting the sub beam at both side positions of the main light receiving area. In this case, the rotation center axis when rotating the light receiver around the optical axis is the main light receiving area. It is preferable to pass through the area. Since the sub beam is arranged symmetrically with respect to the main beam, the position of the sub light receiving region can be aligned with the optical axis of the sub beam if the rotation center axis of the light receiver is defined so as to pass through the main light receiving region. it can.
[0020]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an optical head device to which the present invention is applied and a method for manufacturing the optical head device will be described with reference to the drawings.
[0021]
[Basic example]
(overall structure)
  FIG. 1 is a schematic configuration diagram showing an optical system of an optical head device to which the present invention is applied.
[0022]
As shown in FIG. 1, the optical head device 1 of this example reproduces and records information on a plurality of types of optical recording media 6 having different substrate thicknesses and recording densities, such as CDs and DVDs. In the optical head device 1, a first laser diode chip 21 that emits a first laser beam L1 for CD reproduction having a wavelength of 780 nm and a second laser beam L2 for DVD reproduction that has a wavelength of 650 nm are emitted. A two-wavelength laser light source 2 (single light source) in which the second laser diode chip 22 is accommodated adjacent to the common package is used. In the two-wavelength laser light source 2, the light emitting point positions of the first laser diode chip 21 and the second laser diode chip 22 are separated by a predetermined interval. The two-wavelength laser light source 2, the common optical system 3, and the optical components constituting the common optical system 3 are mounted on a device frame (not shown).
[0023]
The common optical system 3 diffracts the first laser beam L1 into three beams out of the first and second laser beams L1 and L2 emitted from the two-wavelength laser light source 2, and outputs the second laser beam L2. , A half mirror 32 that reflects the first and second laser beams L2 from the diffraction grating 31, a collimator lens 33 that converts the laser beams from the half mirror 32 into parallel beams, and parallel beams. An objective lens 34 that converges on the recording surface of the optical recording medium 6 is included.
[0024]
The common optical system 3 receives the return lights LR1 and LR2 of the first and second laser beams L1 and L2 that have been reflected by the recording surface of the optical recording medium 6 and then passed through the half mirror 32. A common light receiver 4 including first and second light receiving elements 41 and 42 is included.
[0025]
(Receiver mounting structure on the equipment frame)
FIG. 2 is an explanatory view showing a position adjusting operation of the light receiver 4 in the optical head device 1 shown in FIG. FIG. 3 is an explanatory diagram showing the first and second light receiving elements 41 and 42 of the light receiver 4 shown in FIG.
[0026]
As shown in FIG. 2, the light receiver 4 is disposed on the attachment surface 61 of the apparatus frame 6 while being mounted on the fixing member 5. The fixing member 5 is a rectangular substrate larger than the light receiver 4, and as described later, the position adjustment in the X direction and the Y direction with respect to the mounting surface 61 of the apparatus frame 6, and the Z direction perpendicular to the mounting surface 61 After the position adjustment in the (optical axis direction) and the angular position are adjusted, it is fixed to the mounting surface 61 of the apparatus frame 6.
[0027]
The light receiver 4 includes a first light receiving element 41 that receives the first return light LR1, a second light receiving element 42 that receives the second return light LR2, and first and second light receiving elements 41 and 42. And a rectangular element substrate 43 formed on the surface.
[0028]
Referring also to FIG. 3, the first light receiving element 41 includes a main light receiving region 411 and sub light receiving regions 412 and 413 on both sides of the main light receiving region 411 in order to detect three beams of the first return light LR1. Yes. In the main light receiving region 411, the light receiving surface is divided into four in the light receiving region for signal detection. The light receiving surface of the second light receiving element 42 is also divided into four parts, and is formed in a region adjacent to the main light receiving region 411 of the first light receiving element 41. Here, the distance D between the second light receiving element 42 and the main light receiving region 411 of the first light receiving element 41 is the distance between the light emitting point positions of the first laser diode chip 21 and the second laser diode chip 22. Approximate agreement. The first light receiving element 41 and the second light receiving element 42 are formed of photodiodes formed by using a semiconductor process, and each light receiving region is formed with high positional accuracy.
[0029]
The light receiver 4 configured in this manner is fixed to the fixing member 5 so that the center of the fixing member 5 and the center position of the second light receiving element 42 coincide. For this reason, the fixing member 5 has opposed sides 501 and 502 (rotation center position defining portion / rotation center position defining means) whose center of the outer shape when viewed from the optical axis side coincides with the center position of the second light receiving element 42. The opposing sides 501 and 502 are symmetrical with respect to the center position of the second light receiving element 42. For this reason, when the fixing member 5 is held by the jigs 91 and 92 and the jigs 91 and 92 are rotated around the center as shown by the arrow R in this state, the fixing member 5 and the light receiver 4 are It rotates around the axis C2 passing through the center of the light receiving element 42.
[0030]
In this embodiment, of the long side and the short side constituting the outer periphery of the fixing member 5, the opposite side corresponding to the short side is the rotation center position defining portion, but the central portion and the diagonal portion of the long side are rotated. The center position defining portion may be used. That is, even when the fixing member 5 is held so that the fixing member 5 is sandwiched between the central part and the diagonal part of the long side by the jig, if the fixing member 5 is rotated at the center of the jig, the fixing member 5 and the light receiver 4 are It rotates around the axis C2 passing through the center of the light receiving element 42.
[0031]
(Adjustment method of the light receiver 4)
In the method of manufacturing the optical head device 1 having such a configuration, when the light receiver 4 is mounted on the device frame 6, first, the opposing sides 501 and 502 of the fixing member 5 are fixed by jigs 91 and 92 from both sides. The light receiver 4 is held so as to be sandwiched, and in this state, the light receiver 4 is moved in the X direction, the Y direction, and the Z direction by the jigs 91 and 92, and the optical axis of the second return light LR2 and the second light reception. The center position of the light receiving surface of the element 42 is matched.
[0032]
Next, when the jigs 91 and 92 are rotated in a state where the opposing sides 501 and 502 of the fixing member 5 are held by the jigs 91 and 92 from both sides, the fixing member 5 is Therefore, the optical axis of the first return light LR1 and the center position of the main light receiving region 411 of the first light receiving element 41 can be made to coincide with each other.
[0033]
After adjusting the position and inclination of the light receiver 4 in this way, the fixing member 5 is bonded and fixed to the apparatus frame 6.
[0034]
(Effect of this embodiment)
As described above, in the optical head device 1 and the manufacturing method thereof according to the present embodiment, the second light receiving element 42 in a state where the optical axis of the second return light LR2 and the center position of the second light receiving element 42 are matched. The optical axis of the first return light LR1 and the center position of the main light receiving region 411 of the first light receiving element 41 are made to coincide with each other. Therefore, the angular positions of the two light receiving elements 41 and 42 can be adjusted in accordance with the inclinations (angular positions) of the two return lights LR1 and LR2, and there is no need to correct the inclinations using the diffraction grating. Further, the first return light is rotated by rotating the light receiver 4 around an axis passing through the center of the second light receiving element 42 in a state where the position of the second light receiving element 42 is aligned with the optical axis of the second return light LR2. Since the position of the first light receiving element 41 is aligned with the optical axis of LR1, when the light receiver 4 is rotated, the optical axis of the second light receiving element 42 and the second light receiving element 42 that have been adjusted in bending angle and position have been adjusted. And the position will not shift. Therefore, the angular positions of the two light receiving elements 41 and 42 can be easily adjusted according to the inclinations of the two return lights LR1 and LR2.
[0035]
In this embodiment, the light receiver 4 is mounted on the apparatus frame in a state of being fixed to a fixing member 5 having a larger outer dimension than the light receiver 4. For this reason, since the jigs 91 and 92 can hold and rotate the large fixing member 5 without holding the small light receiver 4, the angular position can be easily adjusted.
[0036]
Further, the fixing member 5 includes opposing sides 501 and 502 (rotation center position defining portions) whose center of the outer shape coincides with the center position of the second light receiving element 42 when viewed from the optical axis side. The light receiver 4 can be rotated around the axis C <b> 2 passing through the second light receiving element 42 simply by rotating the fixing member 5 while holding the fixing member 5 at 501 and 502. Therefore, the angular positions of the two light receiving elements 41 and 42 can be easily adjusted according to the inclinations of the two return lights LR1 and LR2.
[0037]
Furthermore, in this embodiment, since the second light receiving element 42 is positioned with priority, higher positional accuracy can be obtained for the second light receiving element 42. Therefore, information recording and reproduction of a DVD having a higher recording density than that of a CD can be performed accurately.
[0038]
[Embodiment 1]
  4 (A), (B), (C)Basic exampleMember for fixing light receiver in optical head device according to the present inventionThe present invention was applied toIt is a top view which shows an example.
[0039]
  Basic exampleThen, although the fixing member 5 used a rectangular substrate,In this example,Instead of a rectangular substrate, as shown in FIG. 4 (A), a fixing member 5A having a shape in which four corners of the rectangle are linearly cut, and as shown in FIG. 4 (B), a rectangular short side 4B, the fixing member 5B having a shape in which a portion corresponding to is formed in an arc shape and four corner portions are cut off, and the four corner portions of the rectangle are cut out so as to be recessed in an arc shape. The fixing member 5C having the shapeUse.
[0040]
If comprised in this way, the circumscribed circle with respect to fixing member 5A, 5B, 5C, ie, the area | region required in order to rotate fixing member 5A, 5B, 5C may be narrowed. Therefore, the operation of rotating the fixing members 5A, 5B, and 5C can be easily performed, and the fixing members 5A, 5B, and 5C can be rotated over a wide angle range.
[0041]
In addition, since each of the fixing members 5A, 5B, and 5C includes a rotation center position defining portion such as an opposing side, the center of the outer shape coincides with the center position of the second light receiving element 42. The light receiver 4 can be rotated around the axis C2 passing through the second light receiving element 42 only by rotating the fixing members 5A, 5B, 5C while holding the fixing members 5A, 5B, 5C.
[0042]
[Embodiment 2]
In the first embodiment, the center of the fixing member 5 is made to coincide with the second light receiving element 42 of the light receiver 4, but the center may be made to coincide with the first light receiving element 41 as described below. In the first embodiment, the fixing member is directly mounted on the apparatus frame. However, as described below, the fixing member is mounted on the apparatus frame via a support member. May be.
[0043]
5A and 5B are a plan view and an exploded perspective view, respectively, showing a fixed state of the light receiver 4 according to Embodiment 2 of the present invention. Since the basic configuration of the second embodiment shown below is the same as that of the first embodiment, the description of common parts is omitted.
[0044]
As shown in FIGS. 5A and 5B, the fixing member 5D to which the light receiver 4 is fixed includes a disk portion 55 larger than the light receiver 4 and a coaxial shape from the disk portion 55 toward the back surface side. The light receiving device 4 is mounted on the disk portion 55.
[0045]
In this embodiment, the light receiver 4 is arranged so that the main light receiving region 411 of the first light receiving element 41 is located at the center position of the disk portion 55. For this reason, the cylindrical portion 56 of the fixing member 5 rotates on the circumferential surface 57 whose center of the outer shape coincides with the center position of the first light receiving element 41 (center position of the main light receiving region 411) when viewed from the optical axis side. Since the center position defining portion is provided, the first fixing member 5D is simply rotated by rotating the fixing member 5D as indicated by the arrow R in a state where the fixing member 5D is held on the circumferential surface 57 by a jig (not shown). The light receiver 4 can be rotated around the axis C1 passing through the center of the light receiving element 41.
[0046]
Here, the fixing member 5 </ b> D is mounted on the attachment surface 61 of the apparatus frame 6 in a state of being mounted on the rectangular support plate 7. A circular opening 71 into which the disk portion 55 of the fixing member 5 is fitted is formed in the support plate 7.
[0047]
In the optical head device 1 configured as described above, when the light receiver 4 is mounted on the device frame 6, first, the disk portion 55 of the fixing member 5 </ b> D on which the light receiver 4 is mounted is circularly formed on the support plate 7. In this state, the circumferential surface 57 of the cylindrical portion 56 is held by a jig, and in this state, the jig is moved in the X direction, the Y direction, and the Z direction, and the first return light LR1. Are aligned with the center position of the main light receiving region 411 of the first light receiving element 41. Then, the support plate 7 is bonded and fixed to the mounting surface 61 of the apparatus frame 6.
[0048]
Next, when the jig is rotated while the circumferential surface 57 of the cylindrical portion 56 is held by the jig, the fixing member 5D has the axis C1 passing through the center of the main light receiving region 411 of the first light receiving element 41. Since it rotates around, the optical axis of the second return light LR2 and the center position of the second light receiving element 42 can be matched.
[0049]
After adjusting the position and inclination of the light receiver 4 in this way, the fixing member 5 is bonded and fixed to the support plate 7.
[0050]
As described above, in the optical head device 1 and the manufacturing method thereof according to the present embodiment, the optical axis of the first return light LR1 and the center position of the main light receiving region 411 of the first light receiving element 41 are matched. By rotating around the axis C1 passing through the center of the main light receiving region 411, the optical axis of the second return light LR2 and the center position of the second light receiving element 42 are matched. Therefore, the angular positions of the two light receiving elements 41 and 42 can be adjusted in accordance with the inclinations of the two return lights LR1 and LR2, and there is no need to correct the inclination using a diffraction grating. Further, in a state where the position of the main light receiving region 411 of the first light receiving element 41 is aligned with the optical axis of the first return light LR1, the light receiver 4 is rotated around the axis C1 passing through the center of the main light receiving region 411. Since the position of the second light receiving element 42 is aligned with the optical axis of the second return light LR2, when the light receiver 4 is rotated, the optical axis of the first return light LR1 that has been adjusted in angle and position is adjusted. The position of the first light receiving element 41 is not shifted. Therefore, the angular positions of the two light receiving elements 41 and 42 can be easily adjusted according to the inclinations of the two return lights LR1 and LR2.
[0051]
In this embodiment, the light receiver 4 is fixed to a fixing member 5D having a larger outer dimension than the light receiver 4. For this reason, since the jig can hold and rotate the large fixing member 5D without holding the small light receiver 4, the angular position can be easily adjusted.
[0052]
Further, the fixing member 5D includes a circumferential surface 57 (rotation center position defining portion) whose center of the outer shape coincides with the center position of the main light receiving region 411 of the first light receiving element 41 when viewed from the optical axis side. Therefore, only by rotating the light receiver 4 while holding the fixing member 5D on the circumferential surface 57, the light receiver 4 is rotated around the axis C1 passing through the center of the main light receiving region 411 of the first light receiving element 41. be able to. Therefore, the angular positions of the two light receiving elements 41 and 42 can be easily adjusted according to the inclinations of the two return lights LR1 and LR2.
[0053]
Furthermore, in this embodiment, since the first light receiving element 41 is rotated about the axis C1 passing through the main light receiving region 411, the sub light reception of the first light receiving element 41 is performed when the second light receiving element 42 is aligned. The positions of the areas 412, 413 can also be automatically adjusted.
[0054]
Further, the fixing member 5D has an advantage that the largest space when viewed from the optical axis side is the disk portion 55, so that the rotation space is narrow.
[0055]
【The invention's effect】
As described above, in the optical head device of the present invention, with the optical axis of one return light and the position of one light receiving element aligned, the light receiver is rotated around the axis passing through one light receiving element. Since the position of the other light receiving element is aligned with the optical axis of the other return light, the angular position of the two light receiving elements can be adjusted according to the inclination of the two return lights, and the inclination is corrected using the diffraction grating. There is no need. In addition, since the light receiver is rotated around the axis passing through one light receiving element with the position of one light receiving element aligned with the optical axis of one return light, when the light receiver is rotated, The position of one light receiving element with respect to the optical axis does not shift. Therefore, the angular positions of the two light receiving elements can be easily adjusted according to the inclinations of the two return lights.
[Brief description of the drawings]
FIG. 1 shows the present invention.ApplyOptical head deviceBasic exampleIt is a schematic block diagram which shows an optical system.
[Figure 2]Basic exampleIn the optical head device according to the above, FIG.
FIG. 3 is an explanatory diagram showing first and second light receiving elements of the light receiver shown in FIG. 2;
FIG. 4 (A), (B), (C) isWhen the present invention is applied to a basic exampleFixing memberExampleFIG.
FIGS. 5A and 5B are explanatory views showing the position adjustment operation of the light receiver in the optical head device according to Embodiment 2 of the present invention. FIGS.
FIGS. 6A, 6B, and 6C are schematic configuration diagrams of a conventional optical head device, a perspective view showing a laser beam that converges on a light receiver, and an explanation that shows the inclination of the emission point of the laser beam. FIG.
[Explanation of symbols]
1 Optical head device
2 Laser light source
3 Common optical system
4 Receiver
5, 5A, 5B, 5C, 5D Fixing member
6 Device frame
7 Support plate
21 First laser diode chip
22 Second laser diode chip
31 Three-beam diffraction grating
32 half mirror
33 Collimating lens
34 Objective lens
41 1st light receiving element
42 Second light receiving element
43 Element substrate
C1, C2 Rotation center axis
55 Disc part
56 Cylinder part
411 Main light receiving area
412, 413 Sub light receiving area
L1 First laser beam
L2 Second laser beam
LR1 first return light
LR2 Second return light

Claims (4)

A first light emitting element that emits a first laser light, and a second light emitting element that emits a second laser light having a wavelength different from that of the first laser light at a position adjacent to the first light emitting element. A light source provided; a first light receiving element that receives the first return light reflected by the optical recording medium; and a second light that the second laser light reflects from the optical recording medium. Manufacturing method of an optical head device comprising: a light receiver including a second light receiving element that receives the return light of the light at a position adjacent to the first light receiving element; and a device frame on which the light source and the light receiver are mounted. In
The light receiver is mounted on the device frame in a state of being fixed to a fixing member having a larger outer dimension than the light receiver,
In the fixing member, the center of the outer shape when viewed from the optical axis side coincides with the position of one light receiving element of the first return light and the second return light, and sandwiches the one light receiving element. A rotation center position defining portion for defining a rotation center axis when rotating the light receiver around the optical axis at a position passing through the one light receiving element is provided on the opposite side surface of the fixed member that is positioned as viewed from the optical axis direction. Sometimes it has a rectangular shape with four corners cut off, or a circular outer shape,
In the step of adjusting the position of the light receiver, the optical axis of one return light of the first return light and the second return light, the first light receiving element, and the second light receiving element Among them, the position of one light receiving element that receives the one return light is aligned,
The fixing member is held by the rotation center position defining portion, the light receiver is rotated around an axis passing through the one light receiving element, and the position of the other light receiving element is aligned with the optical axis of the other return light. A method of manufacturing an optical head device. A first light emitting element that emits a first laser light, and a second light emitting element that emits a second laser light having a wavelength different from that of the first laser light at a position adjacent to the first light emitting element. A light source provided; a first light receiving element that receives the first return light reflected by the optical recording medium; and a second light that the second laser light reflects from the optical recording medium. In an optical head device comprising: a light receiver including a second light receiving element that receives the return light of the light at a position adjacent to the first light receiving element; and a device frame on which the light source and the light receiver are mounted.
The light receiver is mounted on the device frame in a state of being fixed to a fixing member having a larger outer dimension than the light receiver,
In the fixing member, the center of the outer shape when viewed from the optical axis side coincides with the position of one of the first light receiving element and the second light receiving element, and the one light receiving element is Rotation center position defining means for defining a rotation center axis when rotating the light receiver around the optical axis at a position passing through the one light receiving element is formed on the opposite side surface of the fixing member located between An optical head device having a shape obtained by cutting four corners of a rectangle or a circular outer shape when viewed from the optical axis direction . In claim 2,
The second laser beam has a shorter wavelength than the first laser beam,
An optical head device characterized in that a rotation center axis line when rotating the light receiver around the optical axis passes through the second light receiving element. In claim 2,
The first laser light is divided into a main beam and sub-beams on both sides of the main beam, while the first light receiving element includes a main light receiving region for detecting the main beam, A sub-light-receiving area that detects the sub-beam at both positions of the light-receiving area,
An optical head device characterized in that a rotation center axis when rotating the light receiver around the optical axis passes through the main light receiving region.

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