JP3166301B2 - Support structure of parallel plate type optical component and optical pickup device using the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a support structure for a novel parallel plate type optical component support structure and an optical pickup using the same.
To a tapping device . Specifically, regarding a support structure of a parallel plate type optical component used for an optical pickup device and the like,
A novel support structure for a parallel plate type optical component, which can achieve high precision as an optical component without causing distortion in the parallel plate type optical component attached to the base member, and
It is intended to provide an optical pickup device used .

[0002]

2. Description of the Related Art FIGS. 4 and 5 show an example in which a conventional support structure for a parallel plate type optical component is applied to a support structure for a base member of a beam splitter of an optical pickup device.

Reference numeral a denotes a base member in which a vertical hole b penetrating in the vertical direction and a horizontal hole c reaching one side from an intermediate portion of the vertical hole b are formed.

A beam splitter d is disposed at a position where the vertical hole b and the horizontal hole c of the base member a intersect so as to be inclined at an angle of 45 degrees with respect to the axis of the holes b and c. .

Reference numerals e and e denote recesses formed in the base member a for separately supporting both end portions of the beam splitter d. One of the recesses e, e is a vertical hole c of the base member a.
At the lower left corner of the portion where
Are formed in the upper right portion of the crossing portion so that the openings face each other.

The space between the two opposing side surfaces f and g forming the recess e is formed to be approximately twice the plate thickness of the beam splitter d, and the two recesses e and e are formed. Are formed to be approximately the same as or slightly larger than the length of the beam splitter d.

[0007] h is a spring member for supporting both ends of the beam splitter d in the recesses e, e, the length of which is the same as the beam splitter d and the width thereof is approximately twice the plate thickness of the beam splitter d. And a spring portion j, j, which is vertically extended from one end of one side edge along the longitudinal direction of the base portion i and whose lower end is bent in a J-shape.

The beam splitter d has both ends located in the recesses e, e. Then, a spring member h is provided between the lower surface of the beam splitter d and the lower side surfaces g, g of the recesses e, e. The beam splitter d is supported by the base member a such that both ends of the beam splitter d are pressed against the upper side surfaces f, f of the concave portions e, e.

[0009]

However, in the above-described conventional support structure for a parallel plate type optical component, the two concave portions e for supporting the beam splitter d, the side surfaces of the side on which the beam splitter d is pressed. If f and f are not smooth surfaces and are not in the same plane, distortion occurs in the beam splitter d whose both ends are individually pressed, and the accuracy as an optical component is extremely reduced. Was.

Therefore, in order not to reduce the accuracy as an optical component, the flatness of the side surfaces f, f of the recesses e, on which the beam splitter d is pressed, and the accuracy that these are in the same plane are considered. Has to be increased, which causes a problem of lowering production efficiency and increasing costs.

It is also conceivable to fix the left and right end portions of the beam splitter d to the concave portions e with an adhesive. However, in this case, when the adhesive changes due to aging, for example, shrinks. In particular, when changes such as shrinkage of the adhesive at the left and right end portions of the beam splitter d are not performed in the same manner (in most cases, this is the case), internal stress is generated in the beam splitter d, and ultimately, distortion occurs. Most of the time.

[0012]

In order to solve the above-mentioned problems, a support structure for a parallel plate type optical component according to the present invention has a smooth reference surface formed in a concave portion of a base member , and one end of the optical component. One side of the part, the spring inserted into the recess
In contact with the reference surface of the base member, or
In a state where it is adhered to the reference surface of the base member by the adhesive
Or it is supported on the base member by both a spring and an adhesive . Further, the optical pickup device of the present invention includes a light source that emits a laser beam, a condensing unit that irradiates the laser beam emitted from the light source toward a recording medium, and An optical component and a base member having a smooth reference surface formed in the recess are provided. The one flat surface of one end of the optical component is inserted into the recess.
Pressed against the reference surface of the base member by the applied spring
Or adhered to the reference surface of the base member with an adhesive
It is supported on the base member in a state or with both a spring and an adhesive .

[0013]

Therefore, according to the support structure of the parallel plate type optical component of the present invention, since the support portion of the parallel plate type optical component to the base member by the spring or the adhesive is only one end, the support portion is provided. Is generated only in the supporting portion, and no distortion occurs in other portions, that is, portions where light is reflected or transmitted, and therefore, high precision as an optical component can be achieved. it can. Further, according to the optical pickup device of the present invention, since the support portion of the parallel plate type optical component to the base member by the spring or the adhesive is only one end, the distortion generated to support the support portion is small. Distortion does not occur in other portions, that is, portions where light is reflected or transmitted, generated only in the support portion, and therefore, an optical pickup device with high optical accuracy can be provided.

[0014]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view showing a supporting structure of a parallel plate type optical component according to the present invention and an optical pickup device using the same.

In each embodiment shown in the drawings, the support structure of the parallel plate type optical component of the present invention is applied to the support structure of a beam splitter of an optical pickup device.

FIG. 1 shows an example of an optical pickup device 1 to which a support structure for a parallel plate type optical component according to the present invention is applied.

Reference numeral 2 denotes a base member in which a vertical hole 3 penetrating in the vertical direction and a horizontal hole 4 reaching one side from an intermediate portion of the vertical hole 3 are formed.

The vertical hole 3 and the horizontal hole 4 of the base member 2 are open at the front (in FIG. 1, the paper side is the front side and the paper back side is the rear side).

Reference numeral 5 denotes a laser diode fixed inside the opening on one side surface of the horizontal hole 4, and reference numeral 6 denotes a grating disposed between the laser diode 5 and the vertical hole 3. . The laser diode 5 is a patent
Equivalent to “light source that emits laser light” in the claims
I do.

Reference numeral 7 denotes a photodiode disposed at the lower end opening of the vertical hole 3, and reference numeral 8 denotes a light receiving lens disposed above the photodiode 7.

Reference numeral 9 denotes a substantially middle position of the vertical hole 3 and the horizontal hole 4
Is a beam splitter arranged at a corresponding position,
The beam splitter 9 is disposed so as to be at an angle of 45 degrees with respect to both the optical axis of the laser diode 5 and the optical axis of the photodiode 7 as described later.

The beam splitter 9 is formed of a parallel plate-shaped half mirror, and has a concave portion 11 formed as described later.
The base member 2 is supported by the spring member 10 with one end thereof inserted.

Reference numeral 12 denotes a collimator lens arranged at the upper end opening of the vertical hole 3, and reference numeral 13 denotes an objective lens above the collimator lens 12 and supported by a biaxial actuator 14. The objective lens 13 is defined in the claims.
It corresponds to “light collecting means”.

The light beam emitted from the laser diode 5 passes through the grating 6, is reflected upward by the beam splitter 9, and is irradiated on the disk surface 15 through the collimator lens 12 and the objective lens 13. .

The return light reflected by the disk surface 15 passes through the beam splitter 9 and the light receiving lens 8 and enters the photodiode 7.

The recess 11 in which the beam splitter 9 is supported
Has a substantially U-shape when viewed from the side, and has a vertical hole 3 in the base member 2.
The opening direction is formed in the lower left corner of the crossing portion of the horizontal hole 4 and the upper direction, and the opening is directed obliquely rightward.

The space between the two opposing side surfaces 16 and 17 forming the recess 11 is formed to be approximately twice the plate thickness of the beam splitter 9, and the depth from the opening surface of the recess 11 to the depth thereof is set. The length up to the surface is substantially 1/3 of the length of the beam splitter 9, and the upper surface 16 of the concave portion 11 has an extended surface which is either the optical axis of the laser diode 5 or the optical axis of the photodiode 7. Is formed at an angle of 45 degrees.

The length of the spring member 10 is substantially the same as the length from the opening surface of the recess 11 to the depth thereof, and the width thereof is substantially the same as the distance between the two side surfaces 16 and 17 of the recess 11. And a spring portion 19 extending rearward from one side edge of the base portion 18 and having a rear end bent in a J-shape.

The spring portion 19 has a lower piece 19a protruding from the base 18, and a U-shaped spring piece 19b whose front end is folded forward and upward from the tip of the lower piece 19a and whose front end is further bent toward the lower piece 19a. The length of the lower piece 19a is slightly smaller than the front-rear width of the beam splitter 9, and
The length of 9b is formed about 1/3 of the lower piece 19a.

The distance between the bent portion 19c of the spring piece 19b and the lower piece 19a is determined by the distance between the two side surfaces 16 and 17 of the recess 11 when the spring member 10 is not subjected to external force. It is formed slightly larger than the interval obtained by subtracting the thickness of the splitter 9.

Thus, one end of the beam splitter 9 in the longitudinal direction is located in the recess 11, and then the lower surface of the beam splitter 9 and the lower surface 17 of the recess 11
The spring portion 19 of the spring member 10 is inserted from the front of the concave portion 11 between them.

The insertion of the spring member 19 into the concave portion 11 is performed by inserting the rear end of the spring portion 19 into the concave portion 11 from the front of the concave portion 11. On the lower surface 17 and the spring piece 1 of the spring portion 19
When the upper surface of the bent portion 19c of the beam 9b abuts on the lower surface of the beam splitter 9, the spring piece 19b is bent so as to reduce the interval between the lower piece 19a and the lower piece 19a. Further, the bent portion 19c of the spring piece 19b is elastically contacted with a substantially central portion of the lower surface of the beam splitter 9 in the front-rear direction.

As a result, the beam splitter 9 has the concave portion 1
1 is supported by the base member 2 so as to be pressed against the upper side surface 16.

Although only one spring portion 19 of the spring member 10 is provided, the present invention is not limited to this, and two spring portions 19 are provided at positions separated in the length direction.
One spring portion may be formed, and the beam splitter 9 may be pressed against the upper surface 16 of the concave portion 11 at two positions in the concave portion 11.

The upper side surface 16 of the recess 11 is formed so as to form an angle of 45 degrees with respect to both the optical axis of the laser diode 5 and the optical axis of the photodiode 7 as described above. Then, by pressing the beam splitter 9, the mounting state of the beam splitter 9 is regulated using the upper side surface 16 of the concave portion 11 as a reference surface.

Since one end of the beam splitter 9 in the longitudinal direction is supported by the spring member 10 on the base member 2, distortion occurs in the portion of the beam splitter 9 pressed by the spring member 10. No distortion occurs in portions other than the pressed portions, that is, portions where the laser beam is reflected or transmitted.

FIG. 3 shows a second embodiment of the support structure for a parallel plate type optical component according to the present invention.

The difference between the second embodiment and the first embodiment is that the means for supporting the beam splitter in the recess is made of an adhesive. The description of this embodiment will be made mainly on the differences from the above-described first embodiment, and the other portions will be described with reference to the first embodiment.
The same reference numerals are given to the same parts as those in the embodiment, and the description thereof will be omitted.

Reference numeral 20 denotes a crossing portion between the vertical hole 3 and the horizontal hole 4 of the base member 2, which is a recess formed in the lower left corner thereof. The recess 20 has a substantially U-shape when viewed from the side. It is formed so that its opening direction is at an angle of 45 degrees to both the optical axis of the laser diode 5 and the optical axis of the photodiode 7.

The recess 20 is formed such that the distance between two opposing side surfaces 21 and 22 forming the recess 20 is slightly larger than the plate thickness of the beam splitter 9, and from the opening surface of the recess 20 to the inner surface thereof. Is about 1/3 of the length of the beam splitter 9.

The beam splitter 9 is supported in the recess 20 by first injecting an adhesive 23 into the recess 20.
Next, one end of the beam splitter 9 is inserted into the recess 20, and the upper surface of the inserted end of the beam splitter 9 is pressed against the upper side surface 21 of the recess 20 and held.

Further, the upper side surface 21 of the concave portion 20 is formed so as to be oriented at an angle of 45 degrees with respect to both the optical axis of the laser diode 5 and the optical axis of the photodiode 7 as described above. By pressing the beam splitter 9 against this, the beam splitter 9 is
The mounting state is regulated using the upper side surface 21 as a reference surface.

In order to press the upper surface of the end of the inserted beam splitter 9 against the upper side surface 21 of the concave portion 20, for example, a thin plate member is inserted into a gap between the lower surface of the beam splitter 9 and the lower side surface 22 of the concave portion 20. It is good to insert.

Since the beam splitter 9 has one end in the longitudinal direction supported by the base member 2 via the adhesive 23, for example, the adhesive 23 undergoes a change such as shrinkage due to aging. Although distortion occurs at the bonded portion of the beam splitter 9, the portion other than the bonded portion, that is,
No distortion occurs in the portion where the laser beam is reflected or transmitted.

[0045]

As is apparent from the above description, the support structure for a parallel plate type optical component according to the present invention has a base member and a parallel plate type optical component ,
A smooth reference surface is formed in the recess, and one side of the optical component is connected to one plane by a spring inserted into the recess.
While pressing against the reference surface of the base
In the state of being adhered to the reference surface of the base member, or
It is characterized by being supported on the base member by both a spring and an adhesive . Further, the optical pickup device of the present invention includes a light source that emits a laser beam, a condensing unit that irradiates the laser beam emitted from the light source toward a recording medium, and and arranged optical components parallel plate has, and a base member formed a smooth reference surface in the recess, the optical component to one flat surface of one end portion, the recess
Is pressed against the reference surface of the base member by the spring inserted
In contact with the reference surface of the base member
With the base part attached or with both spring and adhesive
It is characterized by being supported by a material .

Therefore, according to the support structure of the parallel plate type optical component of the present invention, since the support portion of the parallel plate type optical component to the base member by the spring or the adhesive is only one end, the support portion is provided. Is generated only in the supporting portion, and no distortion occurs in other portions, that is, portions where light is reflected or transmitted, and therefore, high precision as an optical component can be achieved. it can. Further, according to the optical pickup device of the present invention, since the support portion of the parallel plate type optical component to the base member by the spring or the adhesive is only one end, the distortion generated to support the support portion is small. Distortion does not occur in other portions, that is, portions where light is reflected or transmitted, generated only in the support portion, and therefore, an optical pickup device with high optical accuracy can be provided.

In the above embodiment, the description has been given of the case where the support structure of the parallel plate type optical component of the present invention is applied to the support structure of the beam splitter of the optical pickup device. However, the present invention is not limited to this. The present invention can be applied to a support structure for an optical component.

The specific shapes and structures shown in each of the above embodiments are only examples of the structure for supporting the parallel plate type optical component of the present invention and the implementation of the optical pickup device using the same . They should not be construed as limiting the technical scope of the present invention.

[Brief description of the drawings]

FIG. 1 is a sectional view of a main part of a first embodiment in which a support structure of a parallel plate type optical component according to the present invention is applied to a support structure of a beam splitter of an optical pickup device together with FIG.

FIG. 2 is an exploded perspective view showing a main part in an enlarged manner.

FIG. 3 is an enlarged sectional view of a main part showing a second embodiment in which the support structure of the parallel plate type optical component of the present invention is applied to the support structure of a beam splitter of an optical pickup device.

FIG. 4 is a cross-sectional view showing an example of a conventional support structure for a parallel plate optical component together with FIG.

FIG. 5 is an exploded perspective view showing a main part in an enlarged manner.

[Explanation of symbols]

2 Base member 5 Light source (laser diode) 9 Parallel plate type optical component 10 Spring member 11 Recess 13 Condensing means (objective lens) 16 Reference surface 20 Recess 21 Reference surface 23 Adhesive

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) G02B 7/182 G11B 7/135

Claims (6)

(57) [Claims] 1. A base member and an optical component having a parallel plate shape, wherein a smooth reference surface is formed in a concave portion of the base member , and one side of one end of the optical component is formed in the concave portion.
A support structure for a parallel plate type optical component, which is supported by being pressed against the reference surface of the base member by a spring inserted into the base member . 2. An optical component having a parallel plate shape with a base member.
And a smooth reference surface is formed in the recess of the base member
The above-mentioned optical component has one end portion having an adhesive surface.
In the state of being adhered to the reference surface of the base member by
A support structure for a parallel-plate optical component, characterized in that the support structure is supported on a flat plate. 3. An optical component having a parallel plate shape with a base member.
And a smooth reference surface is formed in the recess of the base member
The above-mentioned optical component has one end portion having an adhesive surface.
Is bonded to the reference surface of the base member by the
Pressure is applied to the reference surface of the base member by a spring inserted
A support structure for a parallel plate optical component, wherein the support structure is supported in a state of being in contact with the optical component. 4. A light source for emitting laser light, a condensing means for irradiating the recording medium with the laser light emitted from the light source, and a parallel light source arranged in a path between the light source and the light condensing means. an optical component a plate, and a base member a smooth reference surface is formed in the recess, the optical component one flat surface of one end thereof, the inner recess
An optical pickup device supported by the base member while being pressed against the reference surface of the base member by a spring inserted into the optical pickup device. 5. A light source for emitting a laser beam, and
Condenser that irradiates the emitted laser beam toward the recording medium
A step, disposed in the path between the light source and the light collecting means
Parallel plate type with optical components and a smooth reference surface in the recess
The optical component is provided with one flat surface at one end thereof by an adhesive.
The base part is adhered to the reference surface of the base member.
An optical pickup device supported by a material . 6. A light source for emitting a laser beam, and
Condenser that irradiates the emitted laser beam toward the recording medium
A step, disposed in the path between the light source and the light collecting means
Parallel plate type with optical components and a smooth reference surface in the recess
The optical component is provided with one flat surface at one end thereof by an adhesive.
And bonded to the reference surface of the base member and the recess.
Pressure is applied to the reference surface of the base member by a spring inserted
An optical pickup device supported by a base member in a state of being in contact therewith.