JP2002032930A - Composite optical unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a composite optical member which is compact and equipped with a beam shaping function and to provide a composite optical unit provided with this member. SOLUTION: A composite optical member 105 which is formed of transparent resin and has a transparent-resin-molded incident plane 105a for a laser beam emitted from a two-wavelength laser diode 102, an outgoing plane 105b that emits the laser beam exiting from this laser diode 102 and that is irradiated with an incident light returning from an optical disk 61 (62), and a reflection area 105d that guides the return light from the optical disk 61 (62) to a light receiving member 104. The incident plane 105a is formed into a cylindrical recessed face, while the outgoing plane 105b into a cylindrical projected face having a different curvature from that of the incident plane 105a otherwise, the incident plane 105a is made to incline in the incident direction of the laser beam emitted from the two-wavelength laser diode 102, the beam shaping function is thereby imparted to the composite optical member 105.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a composite optical unit provided, for example, in a pickup body of an optical disk drive, and more particularly to a mounting structure of a beam shaping member to a housing having a light emitting member.

[0002]

2. Description of the Related Art First, an optical unit for a compact disk (CD) provided with a conventional composite optical member will be described with reference to FIGS. FIG. 18 is a partial sectional view of a conventional optical unit 50, and FIG. 19 is a partially exploded perspective view of the conventional optical unit 50.

[0003] As shown in FIG.
Reference numeral 0 denotes a light source 46 that emits laser light (wavelength 780 nm band) for CD, a light receiving member 47 that receives laser light reflected by a CD (not shown), and a substrate unit having the light source 46 and the light receiving member 47. 48a and a side wall portion 48b attached and fixed to the substrate portion 48a so as to include the light source 46 and the light receiving member 47.
And an emission part 48d which is an opening window of the side wall part 48b, and a light-transmissive composite optical member 49 such as glass joined so as to cover the emission part 48d.

A light source 46 is fixed on a substrate 48 a so as to face the composite optical member 49, and a light receiving member 47.
Are formed on the surface of the substrate portion 48a close to the light source 46. The diffraction grating 49 a formed on the upper end surface of the composite optical member 49 diffracts the return light emitted from the light source 46 and reflected by the CD to guide it to a predetermined position on the light receiving member 47. In addition, a beam forming portion 49b, which is a diffraction grating, is provided on the lower end surface of the composite optical member 49 in order to perform tracking control by the three-beam method.

As shown in FIG. 19, the composite optical member 49 is moved relative to a housing composed of a substrate portion 48a and a side wall portion 48b in an x direction and a y direction orthogonal to the optical axis N and in a rotational direction around the optical axis. The optical axis is adjusted in a certain θ direction. The optical axis alignment between the composite optical member 49 and the housing is
This is performed by holding the composite optical member 49 with a jig (not shown) having a fine adjustment mechanism and operating the fine adjustment mechanisms in the x, y, and θ directions. After the completion of the optical axis alignment, the composite optical member 49 is bonded to the emission part 48d of the housing.

[0006]

The optical unit 50 according to the prior art described above uses a jig provided with a fine adjustment mechanism,
The optical axis alignment of the composite optical member 49 with respect to the housing is represented by x
The adjustment must be performed in three directions, i.e., the y direction and the .theta. Direction, and the adjustment range is very small.
There is a problem that it is difficult to manufacture 0 efficiently.

Further, the composite optical member 4 with respect to the housing
Since the composite optical member 49 needs to be bonded to the housing after the completion of the optical axis alignment of No. 9, there is a problem that the working process is also complicated from this point.

Further, the optical unit 50 according to the conventional example is not provided with a beam shaping member for shaping the spot shape of the laser light emitted from the light source 46 into a circle, so that the laser power applied to the optical disk is There is also a problem that the method cannot be applied to an optical disk device that records and reproduces information by mounting a write-once or rewritable optical disk that requires a larger laser power. In this case, if a beam shaping member such as a triangular prism or a cylindrical lens is incorporated in the optical unit 50, such inconvenience can be solved. Since the manufacturing efficiency of the optical unit 50 is further reduced by using a jig having the above, there is a demand for an improved mounting structure of the beam shaping member to the housing.

SUMMARY OF THE INVENTION The present invention has been made to solve such a technical problem, and an object of the present invention is to provide a composite optical unit capable of easily and accurately mounting a beam shaping member to a housing. is there.

[0010]

In order to solve the above-mentioned problems, the present invention firstly provides a cylindrical housing, a light emitting member provided at one end of the housing, and a light emitting member provided in the housing. A beam shaping member for shaping the spot shape of the laser light emitted from the light emitting member into a circular shape and emitting the light, and between the inner surface of the housing and the beam shaping member, emitted from the light emitting member. First regulating means for regulating the inclination angle of the beam shaping member with respect to the optical axis of the laser light, and regulating the rotational direction position of the beam shaping member around the optical axis of the laser light emitted from the light emitting member. And a second regulating means.

Secondly, the beam shaping member has a beam shaping portion, a flange portion protruding from the beam shaping portion, and a regulating protrusion formed on the flange portion. On the inner surface, a step portion to which the end surface of the flange portion is applied and a restriction groove for inserting the restriction protrusion are formed, and the step portion and the end surface of the flange portion constitute the first restricting means. The second regulating means is constituted by the regulating groove and the regulating protrusion.

Third, a beam shaping member having a cylindrical lens formed in the beam shaping section is used, and the center axis of the cylindrical lens and the optical axis of the laser beam emitted from the light emitting member are coaxial. Wherein the laser light is perpendicularly incident on the lens surface of the cylindrical lens, and the laser light beam-shaped in the central axis direction of the cylindrical lens is emitted.

Fourth, as the beam shaping member, a beam shaping unit having a triangular prism formed therein is used.
The optical axis of the laser light emitted from the light emitting member is obliquely arranged with respect to the incident surface of the triangular prism, and the laser light is obliquely incident on the incident surface of the triangular prism, and a central axis of the housing is provided. It is characterized by emitting laser light beam-shaped in the direction.

Fifth, at least three fixing projections which are pressed against the inner surface of the housing are provided at equal intervals on the outer peripheral surface of the flange portion.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of a composite optical member according to the present invention and a composite optical unit having the same will be described below with reference to FIGS.

FIG. 1 is a configuration diagram of an optical pickup device 100 including a composite optical unit according to the first embodiment, and FIG.
3 is a perspective view of the two-wavelength laser diode 102 partially sectioned, FIG. 3 is a front view of the composite optical member 105 according to the first embodiment, FIG. 4 is a left side view of FIG. 3, and FIG. 5 is a right side view of FIG. 6, FIG. 6 is a view from the direction of arrow 6 in FIG. 3, FIG. 7 is a plan view of the beam shaping member 109 according to the first embodiment, FIG. 8 is a sectional view taken along line 8-8 in FIG. FIG. 9 shows the housing 10.
6, FIG. 10 is a sectional view taken along line 10-10 of FIG. 9, FIG. 11 is a left side view of FIG. 10, FIG. 12 is a right side view of FIG. 10, and FIG. FIG. 14 is a partial cross-sectional view taken along line 14-14 in FIG. 1,
FIG. 15 is an explanatory diagram for explaining the function of the composite optical member 105.

As shown in FIG. 1, an optical pickup device 1
00 is a pickup body, that is, a carriage 500.
, A composite optical unit 101 disposed in the carriage 500, a flat reflecting mirror 300, a collimating lens 400, and an objective lens 200. A member 109 is provided.

The optical pickup device 100 includes an optical disk, for example, a CD 61 or a DVD (digital versatile disk or digital video disk) 62
Focusing (F) which is arranged in a direction orthogonal to the disk surface of the CD 61 (DVD 62).
The objective lens 200 is movably supported in the tracking direction (T), which is the radial direction of the CD 61 (DVD 62). The objective lens 200 is a CD61 and a DV.
It is configured to be compatible with both D62.

The composite optical unit 101 irradiates a laser beam onto the optical disk, and reflects light (return light) from the optical disk.
A light receiving / emitting integrated optical element used for reproducing information recorded on an optical disk by receiving light, or for recording information on an optical disk.
As shown in FIG. 5, mainly a two-wavelength laser diode 102 as a light emitting member, a light receiving member 104 having a built-in light receiving element 104a, a composite optical member 105, a beam shaping member 109, a printed board 107, and these members And a housing 106 to be attached and fixed.

As shown in FIG. 2, the two-wavelength laser diode 102 has a disc-shaped substrate portion 102a and a substrate portion 102a.
a, a rectangular parallelepiped base 102b protruding from one flat portion 102a ', a laser chip 103 positioned and fixed on the side wall surface of the base 102b, and a flat portion 102a' including the base 102b. A cylindrical body 1 that is attached and fixed
A transparent plate-shaped glass plate 102f fixed to cover the opening 102d 'from the inside of the cap 102e, and a cap portion 102e composed of a top plate 102d having an opening 102d' and an opening 102d '; Substrate section 102a
The laser chip 103 is disposed in a closed space formed by the laser chip 103 and a cap 102e and a glass plate 102f. The laser chip 103 includes a light source 103a that emits a short-wavelength (wavelength 650 nm band) laser beam 103a 'for DVD and a long-wavelength (wavelength 780n) for CD.
The light source 103b that emits the laser light 103b 'of the m band) is formed at a small interval D. In this embodiment, the interval D is set to 120 μm. In addition, the 650 nm band for DVD is, specifically, 6 band.
35 nm or 650 nm has been adopted as the DVD standard.

The laser beams 103a 'and 103b' respectively emitted from the light sources 103a and 103b are emitted through the openings 102d 'so as to be parallel to each other in a direction orthogonal to one plane 102a' of the substrate 102a. Is done. The emission positions of the laser beams 103a 'and 103b' are set at the tip surface 103 'of the laser chip 103 (flat portion 1).
02a 'is arranged on the same plane. Further, the substrate unit 102
A plurality of external connection terminals 102g (see FIG. 1) are protruded from the other flat portion 102a 'on the side opposite to the one flat portion 102a', and the laser chip 103 is connected to the laser chip 103 via the external connection terminals 102g. It supplies drive current.

In the process of manufacturing the two-wavelength laser diode 102, the laser chip 103 having the two light sources 103a and 103b is processed on a predetermined substrate surface by a process similar to a semiconductor process.
The distance D between a and 103b can be easily and uniformly formed to a predetermined value with high accuracy. In addition, since mass production of discrete components is possible, the cost of the two-wavelength laser diode 102 can be reduced.

As shown in FIG. 1, the light receiving member 104 includes a package 104 having a light receiving element 104a built therein and a light receiving window 104b 'provided on the light receiving surface side of the light receiving element 104a.
b, and external connection terminals 104c protruding from both sides from the package 104b.
The supply of the power supply voltage to the power supply and the output of the signal photoelectrically converted by the light receiving element 104a to the outside are performed via the external connection terminal 104c.

The composite optical member 105 shown in FIGS.
Is a substantially conical base portion 105 formed of a molded body of a resin material having high transparency and having both end faces in the direction of the optical axis N formed in parallel.
c, an incident surface 105a of the laser light emitted from the two-wavelength laser diode 102, an emission surface 105b for emitting the laser light emitted from the two-wavelength laser diode 102 toward the optical disk, and a return light from the optical disk. And the reflection surface 105d for guiding the light to the light receiving element 104a are integrally formed. In the composite optical member 105 according to the present embodiment, both end surfaces of the base portion 105c are an incident surface 105a and an exit surface 105b of the laser beam, respectively, and the incident surface of the return light from the optical disk is the exit surface. 105b, so that return light from the optical disk is incident on the emission surface 105b.

As shown in FIGS. 3 and 4, the incident surface 105a diffracts the laser light emitted from the two-wavelength laser diode 102 and irradiates a CD for tracking control and data reproduction. A three-beam generation diffraction grating 105h for generating a beam is formed, and
As shown in FIGS. 6 and 8, a rectangular first diffraction grating 105f for guiding the return light from the optical disk to the reflection surface 105d is formed at the center of 05b.

The reflection surface 105d is an inclined surface that is inclined with respect to both end surfaces of the composite optical member 105, and the surface of the reflection surface 105d has a return light path as shown in FIGS. Reflection type second diffraction grating 1 for correcting
05 g are formed. In the transmission path of the return light reflected by the reflection surface 105d, a flat surface 105n is formed over the peripheral surface of the base portion 105c. As shown in FIG. 6, a cylinder surface 1 for performing focus control by the astigmatism method is provided from the edge of the flat surface 105n.
05i is formed in a groove shape having a predetermined angle α with the optical axis N, and the inner wall of the cylinder surface 105i is a return light emission surface 105p.

The composite optical member 1 according to this embodiment is
05, the first and second diffraction gratings 105
f, 105g and a three-beam diffraction grating 105h are integrally formed with the incident surface 105a, the outgoing surface 105b, the base portion 105c, the reflecting surface 105d, and the cylinder surface 105i using a molding die. Each of these diffraction gratings 105
The functions of f, 105g, and 105h will be described later in more detail.

The base portion 105c is formed in a substantially conical shape whose diameter gradually decreases from the incident surface 105a side to the emission surface 105b side, and a columnar portion 105j is formed at the front end of the base portion 105c. The cylindrical surface 105j 'serves as a first restricting portion of the composite optical member 105 with respect to the housing 106.

On the rear end side of the base portion 105c, that is, on the outer peripheral surface on the side where the incident surface 105a and the reflective surface 105d are formed,
As shown in FIG. 3 and FIG. 4, 4 having a semi-cylindrical outer surface
The protrusions 105k 'are formed so as to be arranged substantially evenly in the circumferential direction, and the top surface of each of the protrusions 105k' serves as a second restricting portion of the composite optical member 105 with respect to the housing 106. Further, as shown in FIG. 3, FIG. 4, and FIG. 15, the rear end surface of the base portion 105c (including a part of the incident surface 105a and a part of the reflection surface 105d) is provided with each of the protrusions 105k. ′, The housing 10
A space 105s for buffering the press-fit of the composite optical member 105 with respect to No. 6 is formed with a counterbore at a predetermined depth. Further, as shown in FIGS. 3 to 6, a columnar position regulating protrusion 105 m is formed to protrude downward at the center of the base portion 105 c, and the outer peripheral surface thereof is formed in the housing 10.
6 serves as a third restricting portion of the composite optical member 105.

The composite optical member 105 according to this embodiment is
Although the outgoing surface 105b and the return light incident surface are the same,
The output surface and the return light incident surface may be separately provided, and the first diffraction grating may be formed on the return light incident surface.

The beam shaping member 109 shown in FIGS. 7 and 8
Is formed of a molded body of a resin material having high transparency, and is projected from a beam shaping portion 109a, a disk-shaped flange portion 109b projecting outward from the beam shaping portion 109a, and an outer peripheral surface of the flange portion 109b. Pin-shaped regulating projection 109c and three semi-cylindrical fixing projections 1 projecting from the outer peripheral surface of the flange 109b at substantially equal intervals.
09d are integrally formed. Beam shaping unit 109
As shown in FIG. 8, a cylindrical lens is formed on a of which one surface 109a ″ is formed in a flat shape and the opposite surface (lens surface) 109a ′ is formed in a cylindrical concave surface. As shown in Fig. 7, the portion 109a is formed at the center of the flange portion 109b, and the fixing projection 109d is formed in parallel with the thickness direction of the flange portion 109b. , And a regulating protrusion 109c is provided at the center of curvature SS of the cylinder surface 109a 'as shown in FIG.
, And a peripheral surface thereof serves as a second restricting portion of the beam shaping member 109 with respect to the housing 106.

As shown in FIG. 1, the beam shaping member 109 is mounted in the housing 106 with the cylinder surface 109a 'facing the two-wavelength laser diode 102 side. Shape the spot into a circle. That is, since the spot shape of the laser light emitted from the two-wavelength laser diode 102 is elliptical, the major axis direction is directed parallel to the curvature center axis SS to the beam shaping unit (cylindrical lens) 109a. By injecting the laser light, it is possible to enlarge the minor axis direction of the laser light and to shape the spot shape of the laser light into a circle.

The housing 106 shown in FIGS.
Consists of aluminum die-cast blocks, mainly
It comprises a cylindrical body 106g and mounting portions 106h and 106i projecting outward from both ends of the cylindrical body 106g. These mounting portions 106h and 106i have rectangular mounting surfaces 106h 'and 106i', respectively.

As shown in FIG. 10, a housing chamber 106a for housing the two-wavelength laser diode 102 shown in FIG. 2 is formed on the inner surface of the left end of the cylindrical body 106g.
On the subsequent left end surface, a two-wavelength laser diode 102
A mounting hole 106b for positioning and mounting is formed. Further, the beam shaping member 10 shown in FIG. 7 and FIG.
A stepped portion 106m for positioning and mounting 9 is counterbore formed. Further, on the inner surface at the right end of the cylindrical body 106g, the composite optical member 10 shown in FIGS.
5 is formed, and a first regulation receiving portion 10 for inserting the first regulation portion (cylindrical surface 105j ') formed in the composite optical member 105 is formed at both ends of the accommodation room 106c.
6j and a second restriction receiving portion 106k for inserting a second restriction portion (projection 105k ') formed on the composite optical member 105.
Are formed respectively. Each of these storage rooms 106
a, 106c and the step 106m are formed concentrically with respect to the central axis N '.

The step portion 106m is formed by the beam shaping member 1
When the flange portion 109b is attached, the beam shaping portion 109a is formed at a predetermined position between the two-wavelength laser diode 102 and the composite optical member 105. Further, the diameter of the stepped portion 106m on the beam shaping member setting side is formed to be slightly smaller than the diameter of a circumscribed circle circumscribing the tip of the fixing projection 109d which is the first regulating portion of the beam shaping member 109 with respect to the housing 106. The beam shaping member 109 can be fixed by press fitting.

An accommodation chamber 106c for accommodating the composite optical member 105 is provided with the two-wavelength laser diode 102.
Is formed in a conical shape in which the diameter on the side of the storage portion 106k for storing is gradually increased and gradually decreases toward the mounting surface 106i '. Also, the first regulation receiving unit 1
The diameter of 06j is set to a size that allows the columnar portion 105j (diameter D1) of the composite optical member 105 (see FIG. 3) to be fitted with high precision. Each protrusion 105k 'provided at the rear end 105k
The diameter is slightly smaller than the diameter D2 (see FIG. 4) of a circumscribed circle circumscribing the tip of the composite optical member 105, and the composite optical member 105 can be fixed by press-fitting.

At the front end of the accommodation chamber 106c, there is formed a positioning portion for positioning the composite optical member 105 in the direction of the central axis N ', that is, an abutting surface 106c'. The abutting surface 106c 'has a circular opening 10
6f is provided so that the first diffraction grating 105f provided in the composite optical member 105 is exposed forward.

Further, FIG.
0 and as shown in FIG.
6c and a U-shaped hole-shaped position regulating groove 106d penetrating the stepped portion 106m, and a fan-shaped guide groove 106d 'connected to the rear end of the position regulating groove 106d and penetrating the rear end of the accommodation chamber 106a. Have been. The position regulating groove 1
The groove width of 06d is determined by the outer peripheral surface of the regulating protrusion 109c protruding from the beam shaping member 109 and the composite optical member 105.
Is set to a predetermined size such that the outer peripheral surface of the position regulating protrusion 105m protruded from the outside can be fitted with high precision. An arrangement surface 106e for arranging the light receiving member 104 is formed in a portion of the storage portion 106g facing the position regulating groove 106d. This arrangement surface 106e, as shown in FIG.
The mounting surface 106 of the mounting portions 106h and 106i
h ′ and 106i ′, when the printed circuit board 107 electrically connected to the light receiving member 104 is attached,
4 is formed with a required step between the mounting surfaces 106h 'and 106i' so as not to interfere with the housing 106.

The block used for the housing 106 is not only an aluminum die cast but also a zinc die cast.
It may be made of a magnesium alloy or another metal.

Hereinafter, referring to FIG.
Two-wavelength laser diode 102, light receiving member 104,
A method of assembling the composite optical member 105 and the beam shaping member 109 will be described.

The composite optical member 105 includes the position regulating protrusion 10.
5m is formed in a guide groove 106d 'formed in the housing 106.
Is inserted through the mounting hole 106b of the housing 106 in a state where the base portion 105c of the incident surface 105a except the diffraction grating 105h is uniformly pressed by a required jig (not shown). Accommodation room 106c
Fit inside. Then, when the outer edge of the emission surface 105b comes into contact with the abutting surface 106c 'formed in the housing chamber 106c of the housing 106, positioning in the direction of the central axis N' with respect to the housing 106 is performed.

At this time, the columnar portion 105j provided on the base portion 105c is connected to the first regulation receiving portion 10 of the accommodation chamber 106c.
6j, the columnar portion 10 of the base portion 105c.
The cylindrical surface 105j '(control surface, see FIG. 3) of 5j abuts on the first control receiving portion 106j, and the position of the front end of the base portion 105c in the direction orthogonal to the optical axis N is controlled with high precision. At the same time, the rear end portion 10c of the base portion 105c is formed.
5k is press-fitted into the second regulation receiving portion 106k provided in the accommodation room 106c. At this time, as shown in FIG.
Each of the projections 105k 'formed on the outer peripheral surface of each of the projections 105k' is uniformly crushed.
Of the base member 105c in the direction perpendicular to the central axis N ', the position of the rear end portion 105k of the base portion 105c is regulated with high precision. From the accommodation room 106c is prevented. Further, the composite optical member 105 is
By fitting into the accommodation room 106c provided in the
Position regulating protrusion 105m formed on composite optical member 105
Is guided by the guide groove 106d 'formed in the housing 106 and fitted into the position regulating groove 106d, so that the position in the rotation direction about the central axis N' is regulated with high accuracy.

As described above, in the composite optical unit 101 of the present embodiment, the position of the composite optical member 105 in the direction of the central axis N 'with respect to the housing 106 is restricted by merely fitting the composite optical member 105 into the housing 106. Since the position regulation in the direction orthogonal to the axis N 'and the position regulation in the rotation direction about the central axis N' can be performed, the assembly of the composite optical unit 101 can be performed easily and with high precision.
Further, in the composite optical unit 101 of the present embodiment, since the space 105s is formed so as to face the space corresponding to the formation of the protrusion 105k 'in the composite optical member 105, the distal end surface of each protrusion 105k' (restriction). Face) to the second regulation receiving unit 106
When abutting on the k, the formed portion of each protrusion 105k 'is elastically deformed toward the space 105s side, so that the press-in force is relieved, and the press-in force more than necessary can be prevented from acting on the composite optical member 105. Thus, it is possible to prevent the distortion of the optical function part, particularly the distortion of the second diffraction grating 105g and the three-beam diffraction grating 105h.

The beam shaping member 109 includes the flange 10
9b is a pin-shaped restricting protrusion 109 protruding from the outer peripheral surface.
c is inserted from the mounting hole 106b of the housing 106 in a state in which c is aligned with the opening of the guide groove 106d 'formed in the housing 106, and one side of the flange portion 109b is uniformly pressed by a required jig (not shown). As a result, the step portion 10 formed on the inner surface of the substantially central portion of the housing 106 is formed.
Fits 6m. Then, when the surface of the flange portion 109b opposite to the pressing side is in contact with the step portion 106m,
Positioning in the direction of the center axis N ′ with respect to the housing 106 is performed.

At the same time, the flange portion 109b
Three semi-cylindrical fixing projections 10 formed on the outer peripheral surface
Since the top (first restricting portion) of 9d is press-fitted into the inner surface of the housing 106, position control in the direction orthogonal to the central axis N 'is performed with high precision, and the beam shaping member 109 comes out of the stepped portion 106m. Is prevented. Further, with the operation of inserting the beam shaping member 109 into the housing 106, a regulating protrusion 109 c (second regulating portion) projecting from the outer peripheral surface of the flange 109 b is formed.
Is guided by the guide groove 106d 'formed in the groove 106d and is fitted into the position regulating groove 106d, so that the position in the rotation direction about the central axis N' is regulated with high accuracy.

As described above, in the composite optical unit 101 of the present embodiment, the beam shaping member 109 is attached to the housing 106.
, The position of the beam shaping member 109 with respect to the housing 106 in the direction of the central axis N ′, the position of the beam shaping member 109 in the direction orthogonal to the central axis N ′, and the position of the beam shaping member 109 in the rotational direction about the central axis N ′. Therefore, the assembly of the composite optical unit 101 can be easily and accurately performed.

The two-wavelength laser diode 102 is formed by inserting the cap portion 102e (see FIG. 2) into the housing chamber 106a of the housing 106 and fitting the base portion 102a into the mounting hole 106b formed in the housing 106. It is fixed to the housing 106. Thereby, as shown in FIG. 15, the optical axis N of the laser light emitted from the two-wavelength laser diode 102 can be automatically matched with the central axis N 'of the housing 6, and the beam shaping unit 1
Since the laser light emitted from the two-wavelength laser diode 102 can be made incident on the center of 09a, the spot shape of the laser light can be shaped into a circle.

As shown in FIGS. 1 and 15, the light receiving member 104 is connected to a housing 106 via a printed circuit board 107.
Attached to. The light receiving member 104 is attached to the printed circuit board 107 by connecting the light receiving window 104b 'of the package 104b to the through hole 1 formed in the printed circuit board 107.
07a and soldering the external connection terminals 104c to lands (not shown) formed on the surface of the printed circuit board 107. In addition, if necessary, the package 104b is connected to the printed circuit board 107 or the housing 1.
06 may be fixed by an adhesive or the like to reinforce. Then, the printed circuit board 107 to which the light receiving member 104 is fixed
Is in a state where the light receiving window 104b 'is disposed so as to face the position regulating groove 106d formed in the housing 106.
The mounting surface 106 of each of the mounting portions 106h and 106i
h ′ and 106i ′, and are fixed by fastening with screws 108 to the housing 106. The printed circuit board 107 on which the light receiving member 104 is mounted is provided with first and second diffraction gratings for returning laser light 103a 'and 103b' emitted from the light sources 103a and 103b by a predetermined reference optical system. 105f and 10
After being adjusted to be optimally guided to the predetermined position P of the light receiving element 104a when diffracted by 5 g, the mounting surface 106
h 'and 106i'.

Next, D by the optical pickup device 100
The reproduction operation of VD62 and CD61 will be described.

In the above configuration, when reproducing the DVD 62, as shown in FIG. 1, the laser light 103a emitted from the light source 103a of the two-wavelength laser diode 102 is used.
a 'is transmitted through the three-beam diffraction grating 105h formed on the incident surface 105a of the composite optical member 105, converted into three beams, transmitted through the first diffraction grating 105f, and emitted from the emission surface 105b. .

Then, the laser beam 103a 'is deflected at an angle of 90 degrees by a reflection mirror 300 arranged at an angle of 45 degrees with respect to the traveling direction of the laser beam 103a' and disposed above the reflection mirror 300. The light enters the collimator lens 400. Then, the laser beam 103 a ′, which has been made substantially collimated by the collimating lens 400, enters the objective lens 200 and is focused on the information recording surface of the DVD 62 by the condensing action of the objective lens 200.

The laser beam (return light) 103a 'reflected by the DVD 62 again passes through the objective lens 200 and the collimating lens 400, is reflected by the reflection mirror 300, and then enters the return light incident surface, ie, the exit surface 105b shown in FIG. Return light 103a'- which is the first-order diffracted light that is incident on the first diffraction grating 105f formed at
It becomes 2. The return light 103a'-2 is further reflected on the return light reflecting surface 105d formed on the composite optical member 105, enters the cylinder surface 105i, and is emitted from the return light exit surface 105p. Then, the emitted return light 103a'-2 passes through the position regulating groove 106d (see FIGS. 8 and 11),
Light receiving position P on light receiving element 104a of light receiving member 104
Incident on.

At this time, the return light 103a'-2 received by the light receiving element 104a is photoelectrically converted to a DV.
The reproduction signal is generated by converting the current output corresponding to the signal on the information recording surface of D62 into a voltage signal, output from the external connection terminal 104b of the light receiving member 104, and transmitted to the outside through the printed circuit board 107. A part of the return light 103a'-2 received by the light receiving element 104a is used for focus and tracking control.

On the other hand, when reproducing the CD 61, the laser beam 103b 'emitted from the light source 103b of the two-wavelength laser diode 102 is diffracted by three beams formed on the incident surface 105a of the composite optical member 105 as shown in FIG. After being transmitted through the grating 105h and converted into three beams, the light is transmitted through the first diffraction grating 105f and emitted from the emission surface 105b. Then, the laser beam 103b 'is guided to the objective lens 200 as in the case of the DVD 62, and
By the light condensing action of 00, an image is formed on the information recording surface of the CD 61.

The return light 10 reflected by the CD 61
3b 'indicates the objective lens 200 and the collimating lens 4 again.
After passing through the first reflection grating 300 and being reflected by the reflection mirror 300, it is incident on the first diffraction grating 105f and becomes return light 103b'-2, which is the first-order diffraction light diffracted at a predetermined diffraction angle. The return light 103b'-2 is further reflected by the return light reflecting surface 105d "formed on the composite optical member 105 and is incident on the cylinder surface 105i. On the cylinder surface 105i, the return light 103b'-2 is an astigmatism for focus control. The aberration is applied, the light exits the return light exit surface 105p, passes through the position regulating groove 106d (see FIGS. 10 and 13), and is received at the light receiving position P of the light receiving element 104a. The returned light 103b'-2 is photoelectrically converted to convert a current output corresponding to the signal on the information recording surface of the CD 61 into a voltage signal, thereby generating a reproduction signal, and the external connection terminal 10 of the light receiving member 104.
4b and transmitted to the outside through the printed circuit board 107. A part of the return light 103b'-2 received by the light receiving element 104a is used for focus control by the astigmatism method and tracking control by the three-beam method.

In the optical pickup device 100, the laser light 103a 'emitted from the emission surface 105b,
A wavelength filter or the like for regulating the diameter of the light beam 103b 'may be provided in the optical path between the emission surface 105b and the objective lens 200.

Next, the function of each of the diffraction gratings 105f, 105g, and 105h provided in the composite optical member 105 will be described.

As shown in FIG. 15, the composite optical member 10
5, a laser beam 103a 'emitted from the emission surface 105b,
DVD62 and CD61 for 103b 'respectively
Return light 103a'-2 is diffracted by the first diffraction grating 105f formed on the emission surface 105b.
And 103b'-2. At this time, since the return light 103b'-2 corresponding to the CD 61 has a longer wavelength than the return light 103a'-2 corresponding to the DVD 62,
The diffraction angle of b'-2 is larger than the diffraction angle of the return light 103a'-2 (a diffraction grating uses the principle that the longer the wavelength, the larger the diffraction angle).

By utilizing the difference between the diffraction angles, the laser beam 103a ', 103b' whose distance between the optical axes is D before being diffracted is returned to the return light reflecting surface 105.
When the return lights 103a'-2 and 103b'-2 return to "d", the arrival positions of both light beams coincide with each other.

However, on the return light reflecting surface 105d "of the composite optical member 105, the return lights 103a'-2 and 103a'-2
Simply reflecting 3b'-2 causes the incident angles of the two laser beams to be different, so that the two return lights 103a'-2 and 103b'-2 are directed to the light receiving position P of the light receiving element 104a so as to coincide with each other. It is not possible. In order to correct this, the return light reflecting surface 105d "is provided with a second diffraction grating 105g. That is, the return lights 103a'-2 and 103b'-2 incident on the second diffraction grating 105g are re-wavelength. Return light reflecting surface 105 using the difference in diffraction angle due to the difference in
Return light 103a'-2 and 103b'- reflected at d "
The two optical axes are matched.

In this manner, the first diffraction grating 105f
Return lights 103a'-2 and 103 diffracted at
b′-2 can be corrected so that both light are received at the light receiving position P of the light receiving element 104a.
Even when using the light receiving members a and 103b, the light receiving member 104 having one light receiving element 104a can receive both laser beams.

As described above, the composite optical unit 101 according to the present embodiment has the housing 106 attached to the optical pickup 100 as shown in FIG.
The two-wavelength laser diode 102 has a laser diode 103a for emitting a short wavelength laser for DVD and a laser diode 103b for emitting a long wavelength laser for CD. The composite optical member 105 is a two-wavelength laser diode 1
02, a light incident surface 105a on which light emitted from the light emitting device 02 enters, and an output surface 105b from which light is emitted, and a first light diffracting return light reflected by an optical disk D1 (D2) provided on the light emitting surface 105b.
And a reflecting surface 10 for reflecting the return light diffracted by the first diffraction grating 105f to the light receiving member 104.
5d, and a second diffraction grating 105g is formed on the reflecting surface 105d for forming light of different wavelengths together at the light receiving position P of the light receiving member 104 with the optical axis thereof aligned. Therefore, one composite optical unit is provided. 101 can support the optical pickup device 100 using two different wavelengths. Further, the number of the light receiving members 104 may be one, and
It is only necessary to adjust only the position and adjust the position, so that the cost in the adjustment step does not increase. Further, since the emission surface 105b of the laser light emitted from the two-wavelength laser diode 102 and the return light incidence surface for receiving the return light from the optical disk are made the same, the configuration can be simplified from this point as well. .

The two-wavelength laser diode 102 includes a substrate 102a, a cap 102e, and a glass plate 102f.
The light receiving member 104 includes a package 104b having a built-in light receiving element 104a and an external connection terminal 104c provided on the package 104b. Since the composite optical unit 101 is a discrete component, and the composite optical unit 101 is formed using members that are manufactured individually at a low cost, the handling of each member is easy, and the assembling work into the housing 106 is facilitated. Member costs and process costs can be reduced.

Further, the composite optical member 105 is formed of an inexpensive resin material, and the first and second diffraction gratings 105f and 105g,
Since the beam diffraction grating 105h and the cylinder surface 105i are integrally formed at the same time, the molding time can be shortened, and the manufacturing cost of the composite optical member 105 can be further reduced.

Further, since the beam shaping member 109 is provided in the housing 106, it is possible to reduce the waste of laser power for irradiating the optical disk, and it is applicable to an optical pickup of an optical disk device such as a DVD device requiring a large laser power. can do.

The beam shaping member 109 includes a beam shaping portion 109a, a flange portion 109b projecting from the beam shaping portion 109a, and a flange portion 109b.
b, and a stepped portion 106m on the inner surface of the housing 106 to which the end surface of the flange portion 109b abuts, and a regulating projection 109c formed on the inner surface of the housing 106.
c is formed, and the stepped portion 1 is formed.
06m and the end face of the flange portion 109b.
Since the regulating means and the regulating groove 106d and the regulating protrusion 109c constitute the second regulating means, the beam shaping member with respect to the optical axis of the laser beam can be formed simply by pressing the beam shaping member 109 into the housing 106. 1
09 can be automatically completed, and no special position adjustment jig is required for assembling the beam shaping member 109 with the housing 106. Therefore, the composite optical unit 101 including the beam shaping member 109 is provided. Of the beam shaping unit 109a, the assembling force acting between the housing 106 and the beam shaping member 109 does not act on the beam shaping unit 109a, and deformation and displacement of the beam shaping unit 109a can be prevented. The optical characteristics of the composite optical unit 101 provided with the above can be improved.

Further, in the composite optical unit according to the present embodiment, the beam shaping unit 109 is used as the beam shaping member 109.
A cylindrical lens is formed on the cylindrical lens 09a, and the central axis of the cylindrical lens and the optical axis of the laser light emitted from the two-wavelength laser diode 102 are arranged coaxially. Since the laser beam is incident perpendicularly and the laser beam shaped in the direction of the central axis of the cylindrical lens is emitted, the beam shaping member 109 is provided in the housing 106 without increasing the radial dimension of the housing 106. Thus, the composite optical unit including the beam shaping member 109 can be made compact.

Next, a composite optical unit according to a second embodiment of the present invention will be described with reference to FIGS. FIG. 16 shows a composite optical unit 1 according to the second embodiment.
FIG. 17 is a sectional view of the beam shaping member 10 provided in the composite optical unit 101 according to the second embodiment.
9 is an enlarged sectional view of a main part of FIG.

As shown in FIGS. 16 and 17, the composite optical unit 101 of the present embodiment comprises a beam shaping section 109.
a is provided with a beam shaping member 109 in which a triangular prism is formed. As shown in FIG. 17, the beam shaping section 109a (triangular prism) has a laser beam incident surface 109a 'formed on an inclined surface inclined with respect to the central axis N', and a laser light emitting surface 109a "having a central axis. The laser beam emitted from the two-wavelength laser diode 102 is formed on a plane perpendicular to the N ′, and the minor axis direction of the laser beam is directed toward the inclined direction of the incident surface 109a ′.
The spot shape of the laser light emitted from the emission surface 109a ″ can be shaped into a circle. That is, as described above, the spot shape of the laser light emitted from the two-wavelength laser diode 102 becomes elliptical. Therefore, by injecting the laser beam with its minor axis direction directed toward the inclined direction of the incident surface 109a ', the minor axis direction of the laser beam can be enlarged, and the spot shape of the laser beam can be shaped into a circle.

The entrance surface 109 with respect to the exit surface 109a "
The inclination angle θ of a ′ is defined as θ = sin ⁻¹ ｛(m ² −1) / (n ² m ^2, where m is the beam expansion rate and n is the refractive index of the resin material forming the composite optical member 105. -1) It can be obtained by｝. From this formula, as an example, m
= 2.5 and n = 1.5, θ = 39.3.

As shown in FIG. 16, the housing 106 of the composite optical unit 101 of the present embodiment has a two-wavelength laser for a stepped portion 106m for setting the beam shaping member 109 and a storage chamber 106c for the composite optical member 105. An accommodation chamber 106a for the diode 102 is provided to be inclined, and a two-wavelength laser diode 102 is provided in the accommodation chamber 106a.
Of the two-wavelength laser diode 102 is inserted into the mounting hole 106b, so that the laser light emitted from the two-wavelength laser diode 102 is incident on the incident surface 10a of the beam shaping part 109a.
9a 'can be incident at a required incident angle at which a required beam shaping effect is obtained.

The other parts are the same as those of the composite optical unit 101 and the beam shaping member 109 according to the first embodiment, and the corresponding parts are denoted by the same reference numerals and description thereof will be omitted.

The composite optical unit 101 of this embodiment has the same effects as the composite optical unit 101 according to the first embodiment, and uses a beam shaping member 109 in which a triangular prism is formed in a beam shaping unit 109a. The optical axis of the laser light emitted from the two-wavelength laser diode 102 is arranged obliquely with respect to the incident surface of the triangular prism,
The laser beam is obliquely incident on the incident surface of the triangular prism, and the laser beam shaped in the direction of the central axis of the housing 106 is emitted. Can be inclined with respect to the mounting portion of the beam shaping member 109 and the mounting portion of the composite optical member 105 in the housing 106, and the mounting of the two-wavelength laser diode 102 to the required mounting portion can be facilitated.

In addition, in the above embodiment, two light sources 103a and 103b having different wavelengths are used as the light emitting members.
The two-wavelength laser diode 102 having
A light emitting member having only one light source can be used, or a light emitting member having three or more light sources having different wavelengths can be used.

In the first embodiment, a beam shaping member 109 having a cylindrical lens formed in a beam shaping section 109a is used. In the second embodiment, the beam shaping member 109 is used as a beam shaping member 109. Although a unit in which a triangular prism is formed is used as the unit 109a, the beam shaping unit 109a may be provided with another beam shaping unit such as a circular diffraction grating instead of the above configuration.

[0076]

As described above, the composite optical unit of the present invention has a light shaping member and a beam shaping member integrally provided in a housing, so that it is possible to reduce the waste of laser power for irradiating an optical disk. For example, the present invention can be applied to an optical pickup of an optical disk device requiring a large laser power, such as a DVD device. A first regulating means for regulating an inclination angle of the beam shaping member with respect to an optical axis of the laser beam emitted from the light emitting member, between the inner surface of the housing and the beam shaping member; and a laser emitted from the light emitting member. Since the second regulating means for regulating the rotation direction position of the beam shaping member with respect to the optical axis of the light is provided, the posture of the beam shaping member with respect to the optical axis of the laser beam can be obtained simply by pressing the beam shaping member into the housing. Since the adjustment can be completed automatically and no special position adjusting jig is required for assembling the beam shaping member with respect to the housing, assembly of the composite optical unit having the beam shaping member can be facilitated.

Further, in the composite optical unit according to the present invention, the beam shaping member includes a beam shaping portion, a flange portion protruding from the beam shaping portion, and a regulating protrusion formed on the flange portion. The inner surface of the housing is formed with a step portion to which the end surface of the flange portion is applied and a restriction groove for inserting the restriction protrusion, and the first restriction means is formed by the step portion and the end surface of the flange portion. And the second regulating means is constituted by the regulating groove and the regulating protrusion, so that the assembling force acting between the housing and the beam shaping member does not act on the beam shaping portion,
Since deformation and displacement of the beam shaping unit can be prevented, the optical characteristics of the composite optical unit including the beam shaping member can be improved.

In the composite optical unit of the present invention, a beam shaping member having a cylindrical lens formed in a beam shaping unit is used, and the central axis of the cylindrical lens and the optical axis of the laser beam emitted from the light emitting member are used. Are arranged coaxially so that the laser beam is perpendicularly incident on the lens surface of the cylindrical lens and the laser beam shaped in the direction of the central axis of the cylindrical lens is emitted. Beam shaping members can be provided in the housing without increasing
The composite optical unit including the beam shaping member can be made compact.

Further, in the composite optical unit of the present invention, a beam shaping member having a triangular prism formed in a beam shaping unit is used, and the laser beam emitted from the light emitting member to the incident surface of the triangular prism is used. Since the optical axis is arranged obliquely, the laser light is obliquely incident on the incident surface of the triangular prism, and the laser light beam-shaped in the direction of the central axis of the housing is emitted, so that the light emitting member of the housing is provided. The mounting portion can be inclined with respect to the beam shaping member mounting portion and the composite optical member mounting portion of the housing,
The attachment of the light emitting member to the light emitting member attachment portion can be facilitated.

Further, in the composite optical unit of the present invention, at least three fixing projections pressed against the inner surface of the housing are provided at equal intervals on the outer peripheral surface of the flange portion constituting the beam shaping member. Since the beam shaping member can be fixed by press-fitting, and other fixing means such as bonding is not required, assembly of the composite optical unit including the beam shaping member can be facilitated.

[Brief description of the drawings]

FIG. 1 is an optical pickup device 10 according to a first embodiment.
It is explanatory drawing which shows 0.

FIG. 2 is a partially sectional perspective view of a two-wavelength laser diode 102 according to the first embodiment.

FIG. 3 is a front view of the composite optical member 105 according to the first embodiment.

FIG. 4 is a left side view of FIG. 3;

FIG. 5 is a right side view of FIG. 3;

FIG. 6 is a view as seen from a direction 6 in FIG. 3;

FIG. 7 is a plan view of a beam shaping member 109 according to the first embodiment.

FIG. 8 is a sectional view taken along line 8-8 in FIG. 3;

FIG. 9 is a plan view of a housing 106 according to the first embodiment.

FIG. 10 is a sectional view taken along line 10-10 of FIG. 9;

FIG. 11 is a left side view of FIG. 9;

FIG. 12 is a right side view of FIG. 9;

FIG. 13 is a view as seen from a direction 13 in FIG. 9;

FIG. 14 is a partial sectional view taken along line 14-14 in FIG. 1;

FIG. 15 is a functional explanatory diagram of the composite optical member 105 according to the first embodiment.

FIG. 16 is a partial cross-sectional view of the composite optical unit according to the second embodiment.

FIG. 17 is a cross-sectional view of a beam shaping member 109 provided in the composite optical unit according to the second embodiment.

FIG. 18 is a partial cross-sectional view of a conventional optical unit 50.

FIG. 19 is a partially exploded perspective view of a conventional optical unit 50.

[Explanation of symbols]

 REFERENCE SIGNS LIST 100 optical pickup device 101 composite optical unit 102 two-wavelength laser diode (light emitting member) 104 light receiving member 105 composite optical member 106 housing 106 m step 109 beam shaping member 109 a beam shaping portion 109 b flange portion 109 c regulating protrusion 109 d fixing protrusion 200 object Lens 300 Reflecting mirror 400 Collimating lens 500 Carriage (pickup body)

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G11B 7/135 H01S 5/022 H01S 5/022 G02B 27/00 EFterm (Reference) 2H042 CA12 CA17 5D119 AA38 BA01 CA09 EB03 FA05 JA08 JC04 JC07 LB07 NA02 5F073 AB06 AB21 AB25 AB27 AB29 BA05 FA06

Claims (5)

[Claims] 1. A cylindrical housing, a light-emitting member provided at one end of the housing, and a laser light emitted from the light-emitting member, which is provided in the housing and shaped into a circular spot, is emitted. A beam shaping member for regulating a tilt angle of the beam shaping member with respect to an optical axis of laser light emitted from the light emitting member between an inner surface of the housing and the beam shaping member.
A composite optical unit comprising: a regulating unit; and a second regulating unit for regulating a rotational direction position of the beam shaping member with respect to an optical axis of the laser light emitted from the light emitting member. 2. The beam shaping member includes: a beam shaping unit; a flange protruding from the beam shaping unit;
Forming a regulating protrusion formed on the flange portion, and forming, on the inner surface of the housing, a step portion to which an end surface of the flange portion is applied, and a regulating groove for inserting the regulating protrusion portion; 2. The composite optical device according to claim 1, wherein the first restricting means is constituted by a portion and an end face of the flange, and the second restricting means is constituted by the restricting groove and the restricting projection. 3. unit. 3. A beam shaping member in which a cylindrical lens is formed in the beam shaping section, and a center axis of the cylindrical lens and an optical axis of laser light emitted from the light emitting member are coaxially arranged. 3. The composite according to claim 2, wherein the laser beam is perpendicularly incident on a lens surface of the cylindrical lens, and emits a laser beam that is beam-shaped in a central axis direction of the cylindrical lens. 4. Optical unit. 4. A beam shaping member in which a triangular prism is formed in the beam shaping unit, and an optical axis of a laser beam emitted from the light emitting member is inclined with respect to an incident surface of the triangular prism. 3. The composite optics according to claim 2, wherein the laser beam is disposed obliquely to the incident surface of the triangular prism, and emits laser light beam-shaped in the direction of the central axis of the housing. 4. unit. 5. The composite optical unit according to claim 2, wherein at least three fixing projections pressed against the inner surface of the housing are provided at equal intervals on an outer peripheral surface of the flange portion.