JPH05303030A - Optical parts fixing device - Google Patents

Abstract

PURPOSE:To prevent deterioration of adhesive strength even if an adhesion area is reduced by sticking one side of optical parts to an adhesion pedestal part by an adhesive agent, and only receiving the other side by a non-adhesion receiving pedestal part without sticking it. CONSTITUTION:In a pedestal 21 to which a triangular prism 20 is fixed, an adhesion pedestal part 21a for fixing a wall thickness part 20a of one side in the bottom face of the triangular prism 20 by an adhesive gent 22, and a non-adhesion receiving pedestal part 21b for supporting a wall thickness part 20b of the other side in the bottom face of the triangular prism 20 without interposing the adhesive agent are provided projectingly. Accordingly, since the triangular prism 20 is stuck in only the part whose wall thickness is thick, the adhesion area becomes small, and influence by hardening and shrinkage of the adhesive agent becomes small. Moreover, since the installation of the triangular prism 20 is not balanced with respect to the centroid, even if moment is generated at the time when external force is applied, no deformation is generated in the triangular prism 20 and it can be supported by the non-adhesion receiving pedestal part 21b, therefore, deterioration of adhesive strength can be prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to various optical devices, and more particularly to an optical component fixing device applied to an optical pickup of an optical information recording / reproducing device.

[0002]

2. Description of the Related Art Conventionally, in an optical device, in which an optical component constituting the device is fixed to a predetermined pedestal portion with an adhesive, the more precise the device is, the more it is affected by the curing shrinkage of the adhesive. The occurrence of distortion of optical parts becomes a big problem. In particular, in the optical pickup, since precise control on the micro order is required, various measures and inventions have been made to suppress the distortion of the above optical components.

FIG. 7 is an explanatory view of a schematic structure of a conventional optical pickup. 1 is a laser diode, 2 is a collimating lens for collimating light emitted from the laser diode 1, and 3 is a polarizing beam splitter. 4 is a deflector. Prism, 5
Is an objective lens, 6 is an optical disc, 7 is a focusing lens,
Reference numeral 9 is a split type light receiving element.

In FIG. 1, the laser beam emitted from the laser diode 1 is reflected by the polarizing beam splitter 3 toward the deflecting prism 4, and further reflected by the deflecting prism 4 toward the objective lens 5. The objective lens 5 converges the laser light and irradiates the optical disc 6 as a minute light spot of about 1 μm to write / read known information on the optical disc 6.

The reflected light from the optical disk 6 passes through the objective lens 5, is reflected by the deflection prism 4 in the direction of the polarization beam splitter 3, passes through the polarization beam splitter 3 and the focusing lens 7, and is reflected by a light branching means (not shown). It is branched to the split type light receiving elements 8 and 9. Then, in the respective split type light receiving elements 8 and 9, an RF signal, a tracking error signal, and a focusing error signal are detected as is known.

FIG. 8 is a perspective view showing a conventional fixed portion of the deflection prism 4, and FIG. 9 is a side view of the fixed portion of FIG. 8, in which a pedestal 10 provided in the optical pickup is provided with a thick side of the deflection prism 4. Only the bottom surface of 4a is adhered using the adhesive 11.

In the above-mentioned method of fixing the deflection prism,
If the entire bottom surface of the deflecting prism 4 is adhered, a large adhesive strength can be obtained, but since the thin side 4b of the deflecting prism 4 is likely to be distorted, the adhering surface should be small and the thick side 4a which is not easily distorted should be adhered. As a result, the occurrence of the distortion is suppressed and the deterioration of the optical characteristics is prevented.

[0008]

As described in the fixing method of the deflecting prism as described above, in the case where only one side of the optical component is bonded in order to reduce the bonding area, the optical component is symmetrical with respect to the center of gravity. Since it is not fixed to the optical axis, when an external force is applied, a moment that wraps around is generated in the portion (thin side 4b in FIG. 9) that is not in contact with the pedestal 10 of the optical component, and the adhesive force is reduced. There is.

An object of the present invention is to provide an optical component fixing device capable of preventing a decrease in adhesive strength even if the adhesive area is reduced.

[0010]

In order to solve the above problems, the present invention provides an optical component fixing device for fixing an optical component to a pedestal using an adhesive, wherein the pedestal has one side on one surface of the optical component. And a non-adhesive receiving pedestal for receiving the other side of the one surface of the optical component.

Further, the present invention is characterized in that at least one of the bonding pedestal portion and the non-bonding pedestal portion is provided with a contact surface portion for positioning an optical component.

Further, a space portion is provided at a boundary portion between the contact surface portion and the bonding pedestal portion or the non-bonding pedestal portion.

[0013]

According to the above means, only one side of the one surface of the optical component is bonded to the bonding pedestal portion with an adhesive, and the other side of the one surface of the optical component is not bonded and is received by the non-bonding receiving pedestal portion. By doing so, the adhesion area on the pedestal is small, the influence of curing shrinkage of the adhesive can be suppressed, and the deformation due to external force other than the adhesion part can be prevented by the non-adhesion receiving pedestal part, so It is possible to prevent a decrease in adhesive strength without deteriorating the wavefront aberration of the component.

Positioning and fixing of the optical component with respect to the pedestal can be performed easily and surely by bringing the optical component into contact with the contact surface portion.

Further, the ridge of the optical component is located in the space provided at the corner which is the boundary between the abutting surface and the pedestal, which results in variation in processing between the corner and the ridge. Irrespective of the above, the optical component can be installed on the contact surface portion and the pedestal without difficulty and accurately, and the adhesive agent excessive for adhesion can be released to the space portion, and the adverse effect of the excess adhesive agent can be prevented. Can be prevented.

[0016]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a perspective view of a first embodiment of the present invention, and FIG.
2 is a side view of the first embodiment of FIG. 1, showing a triangular prism 20 which is a deflecting prism as one type of optical component,
The pedestal 21 to which the triangular prism 20 is fixed has a triangular prism.
An adhesive base 21a for fixing the thick portion 20a on one side of the bottom surface of 20 with an adhesive 22 and a thin portion 20b on the other side of the bottom surface of the triangular prism 20 for non-adhesive reception. A pedestal portion 21b is provided so as to project.

In the above-described first embodiment, only the thick wall portion 20a which is hard to be affected by the curing shrinkage of the adhesive 22 is bonded to the bonding pedestal portion 20a, and only the thick wall portion 20a on one side of the triangular prism 20 is bonded. In order to eliminate the imbalance of support due to adhesive fixing, the thin portion 20b on the other side is not attached to the pedestal 2
Received in 1b.

Therefore, since the triangular prism 20 is adhered only to the thick portion, the adhering area becomes small and the influence of the curing shrinkage of the adhesive becomes small. Moreover, since the installation of the triangular prism 20 is not balanced with respect to the center of gravity, even if a moment occurs when an external force is applied, the triangular prism 20 can be supported by the non-adhesive pedestal portion 21b without being deformed. The deterioration of the adhesive strength can be prevented without deteriorating the distortion of the wavefront of the triangular prism 20.

Further, the difference between the materials of the triangular prism 20 and the pedestal 21 (for example, the coefficient of thermal expansion of glass as the material of the triangular prism: 7 × 10 ⁶ / deg., The coefficient of thermal expansion of aluminum as the material of the pedestal: The stress caused by the change in environmental temperature based on 24 × 10 ~ ⁶ / deg.) Is caused by the thin portion 20b of the triangular prism 20.
Since the non-bonded pedestal portion 21b and the non-bonded pedestal portion 21b can freely move with respect to each other, they are relaxed.

FIG. 3 is a perspective view of the second embodiment of the present invention, and FIG.
FIG. 4 is a side view of the second embodiment of FIG. 3, and the difference of the second embodiment from the first embodiment is that the pedestal 21a of the pedestal 21 has side edges of the pedestal 21a and the non-adhesive pedestal 21b. The construction is such that standing walls 25 and 26, which are contact surfaces, respectively, are provided in a protruding manner.

The standing walls 25 and 26 are provided so as to be accurately positioned with respect to the pedestal 21, and the side portions of the triangular prism 20 are brought into contact with the standing walls 25 and 26, respectively, so that the triangular prism 20
Can be easily positioned.

FIG. 5 is a perspective view of a third embodiment of the present invention, and FIG.
5 is a side view of the third embodiment of FIG. 5, and the difference of the third embodiment from the second embodiment is that the pedestal 21a for bonding and the non-bonded pedestal 21b of the pedestal 21 and the standing walls 25, 26 are different. It is configured such that gaps 30 and 31 that are space portions are provided at the corners that are the boundary portions between and.

Usually, the ridge portion E of the triangular prism 20, or the pedestal portion 21a for adhesion and the non-adhesion pedestal portion 21b and the standing wall 25,
There is a minute curved surface in the corner portion that is the boundary with 26, but if there is a difference in the state of both curved surfaces due to differences in processing accuracy, etc., the triangular prism 20 is fixed to the pedestal portion 21a, 2
When the 1b and the standing walls 25 and 26 are brought into contact with each other, the ridge portion E is distorted and the wavefront accuracy is deteriorated.

In the above third embodiment, the pedestal portion 21a for bonding is used.
Since the ridges E of the triangular prism 20 are located in the gaps 30 and 31 provided at the boundary between the non-bonded pedestal portion 21b and the standing walls 25 and 26, they do not abut each other at this portion.
It is possible to set the triangular prism 20 at a predetermined position without generating an unreasonable force when fixing and without deteriorating the wavefront aberration.

Further, in the bonding pedestal portion 21a, the extra adhesive 22 at the time of bonding will enter into the gap 30, so that it can be prevented from wrapping around between the standing wall 25 and the triangular prism 20, resulting in excess bonding. Prevent the adverse effects of the agent.

The shapes and the number of the pedestals 21a and 21b, the standing walls 25 and 26, and the gaps 30 and 31 are not limited to those in the above embodiment, and may be set appropriately according to the specifications.

[0028]

As described above, according to the present invention,
By fixing or supporting one side of the optical component with the adhesive pedestal and the other side with the non-adhesive pedestal, the adhesive area of the optical component can be reduced and the effect of curing shrinkage of the adhesive can be suppressed. Since it is possible to prevent deformation due to external force, it is possible to prevent deterioration of the adhesive strength without deteriorating the wavefront aberration of the optical component even when fixing with an adhesive, and to apply the pedestal of each pedestal part. The optical part can be easily and surely positioned and installed on the surface part, and the ridge part of the optical part is located in the space part of the boundary part between the contact surface part and the pedestal part. Provided is an optical component fixing device which can prevent an adhesive force from being reduced even if a bonding area is reduced, such as adding an optical component accurately without adding a space, and utilizing a space portion as a relief portion for an excess adhesive. This Can.

[Brief description of drawings]

FIG. 1 is a perspective view of a first embodiment of an optical component fixing device of the present invention.

2 is a side view of the first embodiment of FIG. 1. FIG.

FIG. 3 is a perspective view of a second embodiment of the present invention.

FIG. 4 is a side view of the second embodiment of FIG.

FIG. 5 is a perspective view of a third embodiment of the present invention.

6 is a side view of the third embodiment of FIG.

FIG. 7 is an explanatory diagram of a schematic configuration of a conventional optical pickup.

FIG. 8 is a perspective view showing a conventional optical component fixing portion.

9 is a side view of the fixed part of FIG. 8. FIG.

[Explanation of symbols] 20 ... Triangular prism (optical component), 21 ... Pedestal, 21a ... Adhesive pedestal portion, 21b ... Non-adhesive pedestal portion, 22 ... Adhesive,
25, 26 ... Standing wall (contact surface part), 30, 31 ... Gap (space part).

Claims (3)

[Claims] 1. An optical component fixing device for fixing an optical component to a pedestal using an adhesive, wherein an adhesive pedestal portion for fixing one side of one surface of the optical component to the pedestal with an adhesive is provided. An optical component fixing device comprising a non-adhesive pedestal portion that receives the other side of one surface. 2. The optical component fixing device according to claim 1, wherein at least one of the bonding pedestal portion and the non-bonding pedestal portion is provided with a contact surface portion for positioning an optical component. 3. The optical component fixing device according to claim 2, wherein a space portion is provided at a boundary portion between the contact surface portion and the bonding pedestal portion or the non-bonding pedestal portion.