JP2009163794A - Light-emitting element holder, and optical pickup device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a light-emitting element holder capable of highly precisely and easily adjusting the tilt angle of a light-emitting element in an emitting direction and positioning an optical pickup device even with a simple configuration, and to provide an optical pickup device. <P>SOLUTION: Since a second member 22 is adjusted to be fixed to the first member 21 of a holder 20 in the state of being biased in a longitudinal direction by the elastic force of a leaf spring 23, the end part of the second member 22 is allowed to abut on the abutting surface 21d of the first member 21. Thus, during heat generation of a semiconductor laser 5, heat conduction from the second member 22 made of a metal to the first member 21 is promoted via the abutting surface 21d, enhancing a heat radiation effect. The cylindrical surface of a projection 21c and a V-shaped groove 22b are disposed on one side with respect to the optical axis of the semiconductor laser 5. Thus, as shown in Fig.7, when the holder 20 is attached to a housing 1, even if there is an obstacle on one side of the semiconductor laser 5, the holder is attached without being blocked, contributing to compact formation of the optical pickup device. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a light-emitting element holder and an optical pickup apparatus, and more particularly to a light-emitting element holder and an optical pickup apparatus suitable for an optical pickup apparatus capable of recording and / or reproducing information with respect to an optical disc.

  An optical pickup device capable of recording and / or reproducing information with respect to an optical disk represented by a CD or a DVD has been developed. In addition, development of an optical pickup device capable of recording and / or reproducing information on a high-density optical disk such as a Blu-ray Disc or an HD DVD using a blue-violet semiconductor laser having a wavelength of about 400 nm is rapidly progressing.

  Here, in the optical pickup device, for example, a semiconductor laser emits laser light so that, for example, the optical axis of the objective lens is aligned with the highest intensity position in the far field pattern of the laser light with reference to the aperture of the objective lens. It is preferable that the adjustment is performed so that the obtained signal characteristics are improved. However, if the holder of the semiconductor laser is a spherical receiver, it can be said that the emission direction can be adjusted three-dimensionally, but it can be said that the adjustment is complicated, and a space for the spherical receiver structure for adjustment is required. There's a problem. On the other hand, the intensity distribution of the light beam emitted from the semiconductor laser has an elliptical cross section in the direction perpendicular to the optical axis, and therefore there are a direction sensitive to an inclination angle deviation in the emission direction and a direction insensitive to the deviation. Therefore, even if some deviation occurs in the insensitive direction, it is not necessary to completely eliminate the deviation. For example, an optical pickup device dedicated to information reproduction of an optical disc may be sufficiently usable.

Here, in Patent Document 1, the laser diode with respect to the base is slidably brought into contact with the pair of angled flat surfaces on the base and the pair of arc surfaces on the holder on which the laser diode is mounted. A configuration capable of arbitrarily adjusting the angle is disclosed. Further, in Patent Document 2, the angle of the semiconductor laser diode with respect to the receiver is arbitrarily adjusted by slidably contacting the V-shaped groove in the receiver and the cylindrical portion of the holder holding the semiconductor laser diode. Possible configurations are disclosed.
JP 2005-115999 A JP 2003-45041 A

  However, according to the prior art disclosed in Patent Document 1, in order to integrate the base and the holder, a complex-shaped sheet metal coupler is provided, which incurs a high cost and labor at the time of assembly. Is increasing. Further, when the laser diode generates heat by emitting laser light, there is a problem that an effective heat dissipation effect cannot be obtained because heat conduction is performed through a coupler having a small contact area.

  In addition, according to the prior art of Patent Document 2, since the shape is complicated, there is a possibility that play may occur if the dimensional accuracy between the receiver and the holder is not increased, and stable adjustment cannot be performed. Furthermore, when the semiconductor laser diode generates heat when irradiated with laser light, there is a problem that the contact area between the receiver and the holder is small and an effective heat dissipation effect cannot be obtained. Furthermore, since the V-shaped groove and the cylindrical portion are present on both sides of the semiconductor laser diode, there is a problem that the size increases and the size of the optical pickup device increases.

  The present invention has been made in view of the above problems, and has a light-emitting element holder and an optical pickup device that can adjust and position an inclination angle in an emission direction with high accuracy and easily with respect to a light-emitting element, while having a simple configuration. The purpose is to provide.

The light-emitting element holder according to claim 1 is a light-emitting element holder of an optical pickup device, and includes a first member having a protrusion that forms a cylindrical surface, and a V-shape that engages with the cylindrical surface of the protrusion. A second member having a groove,
The first member and the second member are held in a state where the cylindrical surface and the V-shaped groove are engaged with each other and abutted against a surface disposed substantially perpendicular to the axis of the cylindrical surface. And
One of the first member and the second member is fixed to the housing, and the other holds the light emitting element, and the cylindrical surface and the V-shaped groove are arranged on one side with respect to the optical axis of the light emitting element. It is characterized by being.

  According to the present invention, the first member provided with the protrusions forming the cylindrical surface and the second member provided with the V-shaped groove engaged with the cylindrical surface of the protrusions are relatively thin. The inclination of the light emitting element in the emission direction can be adjusted with a simple configuration. In addition, the first member and the second member are fixed by adjusting the tilt while being biased so as to be abutted against a surface arranged substantially perpendicular to the axis of the cylindrical surface when the tilt is adjusted. Then, by releasing the bias after the adjustment, the light emitting element can be positioned with high accuracy, and the change with time can also be suppressed. When the light emitting element generates heat, heat conduction can be promoted between the second member and the first member through the abutting surface, and the heat dissipation effect can be enhanced. Further, since the cylindrical surface and the V-shaped groove are arranged on one side with respect to the optical axis of the light emitting element, the installation space can be reduced compared with the case where they are arranged on both sides, and the optical pickup device is compact. Contribute to The “V-shape” does not necessarily have a V-shaped cross section, and it is sufficient to have a pair of non-parallel planes or curved surfaces.

  The light-emitting element holder according to claim 2 is characterized in that, in the invention according to claim 1, the first member is fixed to the housing, and the light-emitting element is press-fitted into the opening of the second member. Therefore, since the V-shaped groove is provided in the second member, an excessive pressing force generated when the light-emitting element is press-fitted can be received on a simple plane, and assembly is easy. become. In addition, the thickness of the second member can be suppressed.

  The light-emitting element holder according to claim 3 is the invention according to claim 1 or 2, wherein the first member and the second member are made of metal, so that the thermal conductivity is increased. Thereby, the heat dissipation effect at the time of heat_generation | fever of the said light emitting element can further be improved.

  The light-emitting element holder according to claim 4 is the invention according to any one of claims 1 to 3, wherein the light-emitting element emits a light flux having an elliptical light intensity distribution in a cross section perpendicular to the optical axis. In the semiconductor laser, the minor axis direction of the elliptical shape is a direction intersecting the axis of the cylindrical surface. Therefore, the angle adjustment of the emission direction of the light emitting element is performed with respect to the cylindrical surface. It is also possible to perform by simply sliding the V-shaped groove. This is because the elliptical minor axis direction is more sensitive to angular deviation than the major axis direction.

  The light-emitting element holder according to claim 5 is characterized in that, in the invention according to any one of claims 1 to 4, the light-emitting point of the light-emitting element is located on the axis of the cylindrical surface. Even when the V-shaped groove is slid relative to the cylindrical surface and the angle of the emission direction of the light emitting element is arbitrarily adjusted, the light emitting point can be prevented from being displaced in the direction perpendicular to the optical axis, This can simplify the adjustment.

  An optical pickup device according to a sixth aspect includes the light-emitting element holder according to any one of the first to fifth aspects.

  According to the present invention, it is possible to provide a light-emitting element holder and an optical pickup device that can adjust and position the tilt angle of the light-emitting element with high accuracy and easily with a simple structure.

  Hereinafter, embodiments of the present invention will be described in more detail with reference to the drawings. FIG. 1 is a cross-sectional view schematically showing the optical pickup device according to the present embodiment, and shows a state at the time of assembly. FIG. 2 is a cross-sectional view of the configuration of FIG. 1 cut along a plane including the line II-II and viewed in the direction of the arrow. The optical pickup device according to the present embodiment can reproduce information from three types of optical discs of HD DVD, DVD, and CD. However, a diffraction grating or the like that generates a light beam for tracking is added. Thus, it is possible to record information. Furthermore, it is sufficient that information can be recorded / reproduced on at least one type of optical disk.

  In FIG. 1, in a housing 1, a first semiconductor laser 5 and a 2 laser 1 package 15 are positioned and fixed by a holder 20 as will be described later, a collimating lens 3, a rising mirror 4, a blue-violet polarized beam. A splitter 6, a power monitor 7, a polarization beam splitter 11, a servo lens 12, a photodetector 13, and a CD diffraction grating 16 are fixed. A λ / 4 wavelength plate 9 is fixed to the actuator 14. 1, the objective optical element 10 is supported by an actuator 14 so as to be displaceable.

  Next, the operation of the optical pickup device according to this embodiment will be described. In FIG. 2, when information is reproduced from an HD DVD, when the first semiconductor laser 5 as the light source is caused to emit light, the laser beam having a wavelength of about 405 nm emitted from the first semiconductor laser 5 is reflected by the blue-violet polarizing beam splitter 6. Further, as shown in FIG. 1, the light is reflected by the rising mirror 4, but a part thereof passes through the rising mirror 4 and is detected by the power monitor 7. The light beam reflected by the rising mirror 4 passes through the collimating lens 3 and the λ / 4 wavelength plate 9 and is condensed on the information recording surface of the HD DVD via the objective optical element 10.

  The light beam reflected from the information recording surface of the HD DVD passes through the objective optical element 10, the λ / 4 wavelength plate 9 and the collimator lens 3, and is reflected by the rising mirror 4, and the blue-violet polarizing beam splitter 6 and the polarizing beam splitter. 11 and enters the photodetector 13 through the servo lens 12, so that information can be reproduced from the HD DVD using the output signal.

  Here, a change in the shape of the light spot and a change in the intensity distribution on the photodetector 13 are detected to perform focus detection and track detection. Based on this detection, the actuator 14 allows the objective optical element 10 to be integrated with the bobbin so as to be focused and tracking driven so that the light beam from the first semiconductor laser 5 is imaged on the information recording surface of the HD DVD. It has become.

  When reproducing information from a DVD, when the second semiconductor laser in the two-laser one package 15 is caused to emit light, a laser beam having a wavelength of around 660 nm emitted from the two-laser one package 15 passes through the CD diffraction grating 16 and is polarized beam splitter. 11, passes through the blue-violet polarizing beam splitter 6, and is further reflected by the rising mirror 4, but part of the light passes through the rising mirror 4 and is detected by the power monitor 7. The light beam reflected by the rising mirror 4 passes through the collimating lens 3 and the λ / 4 wavelength plate 9 and is condensed on the information recording surface of the DVD via the objective optical element 10.

  The light beam reflected from the information recording surface of the DVD passes through the objective optical element 10, the λ / 4 wavelength plate 9 and the collimator lens 3, is reflected by the rising mirror 4, and is converted into a blue-violet polarizing beam splitter 6 and a polarizing beam splitter 11. , And enters the photodetector 13 via the servo lens 12, so that information can be reproduced from the DVD using the output signal.

  Here, a change in the shape of the light spot and a change in the intensity distribution on the photodetector 13 are detected to perform focus detection and track detection. Based on this detection, the actuator 14 can perform focusing and tracking drive integrally with the bobbin by the actuator 14 so that the light beam from the second semiconductor laser is imaged on the information recording surface of the DVD. Yes.

  When information is reproduced from the CD, when the third semiconductor laser in the two-laser one package 15 is caused to emit light, the laser light beam having a wavelength of about 785 nm emitted from the CD enters the CD diffraction grating 16 and the tracking signal. ± 1st order diffracted light is generated. The laser beam is reflected by the polarizing beam splitter 11, passes through the blue-violet polarizing beam splitter 6, and is further reflected by the rising mirror 4, but part of the laser beam passes through the rising mirror 4 and passes through the power monitor 7. Detected. The light beam reflected by the rising mirror 4 passes through the collimating lens 3 and the λ / 4 wavelength plate 9 and is condensed on the information recording surface of the CD via the objective optical element 10.

  The light beam reflected from the information recording surface of the CD passes through the objective optical element 10, the λ / 4 wavelength plate 9 and the collimator lens 3, is reflected by the rising mirror 4, and is converted into a blue-violet polarizing beam splitter 6 and a polarizing beam splitter 11. , And enters the photodetector 13 via the servo lens 12, so that information can be reproduced from the CD using the output signal.

  Here, a change in the shape of the light spot and a change in the intensity distribution on the photodetector 13 are detected to perform focus detection and track detection. Based on this detection, the actuator 14 can perform focusing and tracking driving integrally with the bobbin by the actuator 14 so that the light beam from the third semiconductor laser is imaged on the information recording surface of the CD. Yes.

  Next, a holder (also referred to as a light emitting element holder) that holds the semiconductor laser according to the present embodiment will be described. FIG. 3 is a perspective view of the holder 20 including the first member 21 and the second member 22, and the outline of the second member 22 is drawn with imaginary lines (dashed lines) for easy understanding. FIG. 4 is a perspective view of the second member 22 to which the semiconductor laser 5 is attached, and FIG. 5 is a perspective view of the first member 21. FIG. 6 is a view of the holder 20 of FIG. 3 as viewed from the direction of the arrow VI. FIG. 7 is a view of the holder 20 of FIG. 3 as viewed from the direction of the arrow VII together with the housing 1 to which the holder 20 is attached. The outline of the second member 22 is drawn with phantom lines (dashed lines) for easy understanding. Hereinafter, the semiconductor laser 5 will be described as an example, but the same applies to the two laser 1 package 15 which is a semiconductor laser.

  In FIG. 5, the first member 21 is made of a metal such as aluminum and has a substantially rectangular plate shape. The first member 21 has an arc-shaped notch 21 a on one end side and a thick portion 21 b on the other end side. Accordingly, the first member 21 has an L-shape in this embodiment when viewed from above in FIG. A semi-cylindrical protrusion 21c is formed so as to extend from the thick part 21b toward the notch 21a. The outer peripheral surface of the protrusion 21c constitutes a cylindrical surface. The periphery where the protrusion 21c is joined to the thick portion 21b forms a contact surface 21d orthogonal to the axis of the protrusion 21c.

  In FIG. 4, the second member 22 is made of a metal such as aluminum and has a substantially rectangular plate shape. The second member 22 has a circular opening 22a in the vicinity of one end, and further extends from the end face 22c at the other end toward the circular opening 22a. A V-shaped groove 22b is formed so as to terminate in front of it. When the second member 22 is viewed from the end face 22c side, the center of the V-shaped groove 22b and the axis of the circular opening 22a preferably overlap. The semiconductor laser 5 is fixed to the circular opening 22 by press-fitting. The optical axis of the semiconductor laser 5 that has been press-fitted is perpendicular to the axis of the cylindrical surface of the protrusion 21c with high accuracy.

  As shown in FIG. 4, the laser light emitted from the semiconductor laser 5 has a light intensity distribution in which the cross section in the direction perpendicular to the optical axis has an elliptical shape OV due to its characteristics. The major axis direction X of the elliptical shape OV is parallel to the axis of the cylindrical surface of the projection 21c, and the minor axis direction Y of the elliptical shape OV is attached to the holder 20 so as to be orthogonal to the axis of the cylindrical surface of the projection 21c. Preferably. Since the semiconductor laser 5 is formed with a notch 5a (FIG. 3) indicating the direction of the ellipse of the emitted laser beam, by assembling it while engaging a jig (not shown), The major axis direction X and the axis of the cylindrical surface of the projection 21c can be positioned in parallel. However, the same effect can be expected even if a convex portion or the like matching the notch 5a is formed corresponding to the second member 22.

  Here, in the major axis direction X of the elliptical shape OV, the change in the light intensity distribution is gentle and the adjustment sensitivity of the laser beam is insensitive. be able to. On the other hand, in the minor axis direction Y of the elliptical shape OV, the change in the light intensity distribution is steep and the adjustment sensitivity of the laser light is sensitive. Therefore, by adjusting as described later, good signal characteristics can be obtained. become able to.

  In FIG. 3, the first member 21 is fixed to the housing 1 (not shown) (see FIG. 1), and the V-shaped groove 22b is engaged with the cylindrical surface of the projection 21c so that the second member 22 is engaged. Is attached. Thereby, the holder 20 which is thin and simplified to the extent that two plate materials are overlapped can be configured. Further, the second member 22 is biased in the longitudinal direction by the elastic force of the leaf spring 23 at the time of adjustment with respect to the first member 21, whereby the end of the second member 22 is It contacts the contact surface 21d. As shown in FIG. 6, the light emitting point O of the semiconductor laser 5 is attached so as to be positioned on the axis of the cylindrical surface of the protrusion 21c.

  In adjusting the angular position of the emission direction of the semiconductor laser 5, the first member 21 and the second member 22 are so arranged that the laser beam is actually emitted from the semiconductor laser 5 and focused on a sensor (not shown) disposed at a predetermined position. By relatively changing the angle. That is, in FIG. 6, along the cylindrical surface (dotted line) of the protrusion 21 c, the V-shaped groove 22 b (one-dot chain line) that contacts at two points on the cross section slides relative to each other, so that it is integrated with the second member 22. Angle adjustment in the minor axis direction Y of the semiconductor laser 5 can be performed. At this time, since the light emitting point O of the semiconductor laser 5 is located on the axis of the cylindrical surface of the protrusion 21c, the V-shaped groove 22b is slid relative to the cylindrical surface to arbitrarily emit the semiconductor laser 5. Even when the angle of the direction is adjusted, the light emitting point O is not displaced in the direction perpendicular to the optical axis. Therefore, the adjustment time can be shortened by making the adjustment independent.

  Furthermore, according to the present embodiment, the second member 22 is adjusted and fixed with respect to the first member 21 while being biased in the longitudinal direction by the elastic force of the leaf spring 23. Since the end surface 22c of the member 22 is in contact with the contact surface 21d of the first member 21, when the semiconductor laser 5 generates heat, both of the end surfaces 22c are made of metal through the contacted end surface 22c and the contact surface 21d. Heat conduction can be promoted from the member 22 to the first member 21 to enhance the heat dissipation effect. Further, since the cylindrical surface of the protrusion 21c and the V-shaped groove 22b are arranged on one side with respect to the optical axis of the semiconductor laser 5, the semiconductor laser is mounted when the holder 20 is attached to the housing 1, as shown in FIG. Even when the tilt adjusting screw SW of the actuator 14 is arranged on one side across the axis 5, attachment can be performed without interfering with this, which contributes to downsizing of the optical pickup device. The plate spring 23 is removed after adjustment and fixing.

  FIG. 8 is a perspective view of the first member 21 ′ according to the modification. This modification is different from the first member 21 shown in FIG. 5 only in that a portion where the arcuate cutout 21a is cut off. Since the arc-shaped cutout 21a is not involved in holding the semiconductor laser 5, even if it is deleted, there is no problem in holding, and the installation space for the holder 20 can be further reduced by the deletion.

  FIG. 9 is a perspective view of a holder 20 ″ according to a modified example, and the outline of the second member 22 ″ is drawn with an imaginary line (dashed line) for easy understanding. In the present modification, notches 21e "and 21f" are formed on the upper and lower edges of the first member 21 "with respect to the holder 20 shown in Fig. 3, and the upper edges of the second member 22" are correspondingly formed. And the lower edge is formed with notches 22e "and 22f" having dimensions larger in the longitudinal direction and depth direction than the notches 21e "and 21f". After adjusting the angle of the semiconductor laser 5, the first member 21 "and the second member 22" can be fixed by filling the notches 22e "and 22f" with an adhesive. Further, when the holder 20 ″ is attached to the housing 1, the holder 20 ″ and the housing 1 can be fixed by filling the notches 21e ″, 21f ″, and 21g ″ with an adhesive.

  The present invention has been described above with reference to the embodiments. However, the present invention should not be construed as being limited to the above-described embodiments, and can be modified or improved as appropriate. For example, the second member may be attached to the housing, and the semiconductor laser may be assembled to the first member.

It is sectional drawing which shows schematically the optical pick-up apparatus concerning this Embodiment. It is sectional drawing which cut | disconnected the structure of FIG. 1 by the surface containing an II-II line, and was seen in the arrow direction. 2 is a perspective view of a holder 20 including a first member 21 and a second member 22. FIG. It is a perspective view of the 2nd member 22 to which the semiconductor laser 5 was attached. 3 is a perspective view of a first member 21. FIG. It is the figure which looked at the holder 20 of FIG. 3 from the arrow VI direction. It is the figure which looked at the holder 20 of FIG. 3 from the arrow VII direction. It is a perspective view of the 1st member 21 'concerning a modification. It is a perspective view of holder 20 '' concerning a modification.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Housing 3 Collimating lens 4 Raising mirror 5 Semiconductor laser 6 Polarizing beam splitter for blue-violet 7 Power monitor 9 λ / 4 wavelength plate 10 Objective optical element 11 Polarizing beam splitter 12 Servo lens 13 Photo detector 14 Actuator 15 2 Laser 1 package 16 CD diffraction grating 20, 20 ″ Holder 21, 21 ′, 21 ″ First member 21a Notch 21b Thick part 21c Protrusion 21d Contact surface 21e ”Notch 21f” Notch 21g ”Notch 22, 22” Second member 22a Circular Opening 22b V-shaped groove 22c End face 22e "Notch 22f" Notch 23 Leaf spring O Light emitting point OV Elliptical SW Screw X Major axis direction Y Minor axis direction

Claims (6)

A holder for a light emitting element of an optical pickup device, comprising: a first member having a protrusion that forms a cylindrical surface; and a second member having a V-shaped groove that engages with the cylindrical surface of the protrusion,
The first member and the second member are held in a state where the cylindrical surface and the V-shaped groove are engaged with each other and abutted against a surface disposed substantially perpendicular to the axis of the cylindrical surface. And
One of the first member and the second member is fixed to the housing, and the other holds the light emitting element, and the cylindrical surface and the V-shaped groove are arranged on one side with respect to the optical axis of the light emitting element. A holder for a light emitting element.   The light-emitting element holder according to claim 1, wherein the first member is fixed to the housing, and the light-emitting element is press-fitted into an opening of the second member.   The light-emitting element holder according to claim 1, wherein the first member and the second member are made of metal.   The light emitting element is a semiconductor laser that emits a light beam whose light intensity distribution has an elliptical cross section in the direction orthogonal to the optical axis, and the minor axis direction of the elliptical shape is a direction that intersects the axis of the cylindrical surface. The holder for light emitting elements according to any one of claims 1 to 3.   The light emitting point of the said light emitting element is located on the axis line of the said cylindrical surface, The holder for light emitting elements in any one of Claims 1-4 characterized by the above-mentioned.   An optical pickup device comprising the light-emitting element holder according to claim 1.

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