JPS6240631A - Optical pickup - Google Patents

Abstract

PURPOSE:To attain ease of wiring, large rigidity, light weight and small size by using a resin as a raw material to form a pickup main body and forming incorporatedly a reinforcement member provided with conductor pattern and external connection part to the main body. CONSTITUTION:The pickup main body 21 is formed by using a resin as a raw material and the reinforcement member 22 is formed incorporatedly to the main body 21. Then, the conductor pattern 23c connected to a light source and an actuator or the like and the external connection part 22e connected to the conductor pattern 23c are provided to the reinforcement member 22. Thus, the wiring in the pickup main body 21 is much facilitated and disconnection of lead wire or the like is avoided. Since the rigidity of the main body 21 is guaranteed sufficiently, deformation at assembling is avoided and light weight small size are attained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an optical pickup that reads information recorded on the recording surface of a recording medium such as a compact disc or writes information onto the recording surface.

[Prior Art and Problems to be Solved by the Invention] Conventionally, information recorded on a recording medium such as a compact disc, a video disc, or an optical disc such as a data disc is read or information is written to this recording medium. Various writing optical pickups have been proposed.

FIG. 3 is a principle diagram showing the operation of an optical pickup of the type that detects a focus error signal by the critical angle method, and is equivalent to that disclosed in, for example, Japanese Patent Application Laid-Open No. 59-201240.

A light beam emitted from a light source 1 such as a semiconductor laser is made into a parallel light beam by a collimator lens 2, and then enters a polarizing prism 3, passes through the polarizing film 3a, and reaches a reflecting prism 4. The parallel light beam totally reflected in the right angle direction by the reflecting surface of the reflecting prism 4 passes through the 174-wave plate 5 and is converged by the objective lens 6, and is applied to the recording surface 10a of the recording medium 10 such as a compact disk with a diameter of about 1 female. Connect a light spot with 1g! Rir.

The objective lens 6 is supported within an actuator 11 including a magnet, a yoke, a coil, etc. so as to be movable two-dimensionally in the optical axis and in the radial direction of the recording medium 10 perpendicular to the optical axis. This actuator 11 performs focus servo and racking servo so that the light spot follows the center of the track of the recording medium 10 in a focused state.

Then, the reflected light of the light spot irradiated onto the recording medium 10 follows the same optical path as the outgoing path through the polarizing film 3a, but in the returning path, its polarization direction is perpendicular to the polarizing direction of the outgoing path due to the action of the 174 wavelength plate 5. Therefore, it is reflected in the 90° direction by the polarized light 11U3a, passes through the critical angle prism 7, and enters the photodetector 8.

This critical angle prism 7 has an optical surface that is such that the incident angle of the return light from the recording medium 10 with respect to the optical axis is approximately a critical angle, and by reflecting the return light on this optical surface, a photodetector 8 is detected. Avoiding the incident. Further, this photodetector 8 has a light receiving surface 8a which is divided into four parts in the radial direction and the tangential direction of the recording medium 10, and receives a data signal, a focus error signal, and a tracking error signal from the output of this light receiving surface 8a. I'm starting to get it.

The members 2 to 7 of the optical system configured in this way, the semiconductor laser 1, the photodetector 8, and the actuator 11 that holds the objective lens 6 are mounted in the pickup body 12 in the longitudinal direction as shown in FIG. 3 (perspective view). The cover 12 is stored along the
a1. : Covered. This pickup body 12 is provided with mounting surfaces 13a and 13b.
3a and 13b are fixed to a carriage (not shown) that reciprocates along the recording surface 10a of the recording medium 10 in a direction across the track.

The drive means for this carriage is, for example, disclosed in Japanese Patent Application Laid-Open No. 57-1999.
It is disclosed in Japanese Patent No. 173656.

By the way, the light source 1, photodetector 8, actuator 1
1 is provided with lead wires for power supply or signals, and each of the lead wires is connected to an external connection terminal such as a connector attached to one side of the pickup main body 12. They are each connected to the control device 211 of the main body of the device through the terminals.

However, the wiring space for the lead wires inside the pickup body 12 is narrow, and during wiring work, the lead wires are connected to the optical systems 2 to 7.
There is a problem that the optical path of the wire may be blocked or the wire may be broken due to being pinched by the cover 128.

To deal with this, it would be better to secure a sufficient wiring space for the pickup main body 12, but this is difficult to realize because it goes against the recent trend toward smaller size and lighter weight.

Further, some of the recent pickup bodies 12 are molded from resin in order to reduce the size and weight. However, when the pickup body 12 is made of a resin molded product, the strength of the pickup body 12 decreases, and the pickup body 12 deforms during assembly, causing the optical path of the light source 1 and the optical axis of the optical system such as the objective lens 7 to There is a problem in that the optical characteristics are deteriorated due to misalignment.

[Purpose of the Invention] The present invention has been made in view of the above circumstances, and is capable of sufficiently guaranteeing the rigidity of the pickup body, realizing a reduction in size and weight, and furthermore, allowing the lead wire to be connected to the optical path of the optical system during wiring work. It is an object of the present invention to provide an optical pickup that improves workability without cutting off or breaking lead wires on both sides.

[Means for Solving the Problems 1] The optical pickup according to the present invention includes a light source in a pickup main body that moves along the recording surface of a recording medium, and a light beam from the light source that irradiates the recording surface. The pickup body is molded from a resin material, and includes an optical system that guides the reflected light from the pickup to a photodetector, and an actuator that corrects the optical system at least two-dimensionally with respect to the recording surface. A reinforcing member is integrally formed on the pickup body, and a conductive pattern connected to the light source, the photodetector, and the actuator 1] is connected to the reinforcing member, and a conductive string is connected to the conductive pattern. The opening provided with the external connection portion sufficiently ensures the strength of the pink-up main body, and minimizes the wiring area for the light source, photodetector, and actuator.

(Example] Hereinafter, the present invention will be described in detail with reference to the drawings.

1 and 2 relate to one embodiment of the present invention, with FIG. 1 being an exploded perspective view of an optical pickup, and FIG. 2 being a perspective view of a reinforcing member.

In these figures, reference numeral 21 is the pickup body, and this pickup body 21 has a ? The reinforcing member 22, which is formed in the shape of a shape, is formed by arranging. The reinforcing member 22 is a glass epoxy substrate, a ceramic substrate, or the like, and the mounting surfaces 22a are opposed to each other on both sides in the longitudinal direction.

A hole 22G is bored in one side of the semiconductor laser 220, and a hole 22G is formed in which a half-8-day laser 1, which is an example of a light source, is mounted, and a lead wire 1a extending from the semiconductor laser 1 is connected below the hole 22G by means such as flat wire bonding. A full ball 23a is provided. In addition, a through hole 23a is formed in the other mounting surface 22b to connect one side of the flexible substrate 24 by means such as solder or a crimp bottle. Further, a through ball 2 to which a lead wire (not shown) of the photodetector 8 is connected to approximately the center of the reinforcing member 22 by means such as soldering.
3a is formed, and next to it is a light receiving surface 8a of the photodetector 8.
A square hole 22d is bored to expose the.

Further, an external connection socket portion 22e having a predetermined width is formed protruding from one side of the reinforcing member 22 in the short side direction. A through hole 23b is formed in this external connection socket portion 22e. These through holes 23b are provided in a horizontal row, and each through hole 23a and each through ball 2
3b are individually electrically connected to each other via conductive patterns 23C formed on the surface of the reinforcing member 22 by means such as printing or adhesion.

Further, reference numeral 25 is a connector plug, and the pin 4 fitted into the through hole 23b is attached to the connector plug 25.
A connector plug 25a is provided, and a connector plug 25 is connected to the connector plug 25a.
Fasteners 25b are formed on both sides of the external connection socket portion 22c to be fixed by bending or other means.

On the other hand, the pickup main body 21 which is integrally formed with the reinforcing member 22 is made of resin itself or polycarbonate resin mixed with carbon fiber, glass fiber, etc.
It is molded from a high tensile If abrasive material such as polyphenylene sulfide, and the reinforcing member 22 is embedded in the bottom thereof. Also, both side surfaces 21a of the pickup main body 21.

21[) to remove the reinforcing portion 4422 from J1 surface 22a, 2
2F) is exposed and J5 is exposed, each side 21a, 21b
The semiconductor laser 1 and the flexible substrate 24 are directly attached to each other.

J. On one side of the pickup main body 21 in the short side direction, a part 22 of the external connection socket 1 of the reinforcing member 22 is provided.
h< is protruded, and this external connection socket part 22
Connector plug 25 attached to through hole 23b of e
The power supply and signal lines from the main body of the apparatus are respectively connected to the bin terminals 25a.

On the other hand, an actuator storage section 26 is formed on the right side of the pickup main body 21 in the figure. A prism mounting part 27 for fixing a reflecting prism 32 is provided on one side of the actuator storage part 26, and an opening formed in the center of the prism mounting part 27 connects the semiconductor laser 1 to the semiconductor laser 1 through an optical axis path (not shown). It is communicated.

Further, the actuator 11 is fixed to the actuator storage portion 26 by screws 30 inserted through a mounting hole 28 formed in the bottom surface thereof. Note that the mounting hole 28 is bored in the reinforcing member 22, and the conductive pattern 23C is inserted into the mounting hole 28. Needless to say, it is formed to avoid Further, a reinforcing member 22 may be provided at the bottom of the actuator storage portion 26 and the actuator 11 may be directly fixed to the reinforcing member 22. This eliminates the need to perform insulation treatment on the conductive pattern 23G last time.

Further, the objective lens 6 is supported by the actuator 11 so as to be movable in the tracking direction and the focusing direction. This objective lens 6 is attached to the prism mounting portion 2
7 and the recording surface 10a of the recording medium 10 (see FIG. 3), and is adapted to be corrected and controlled in the tracking direction and the focusing direction by a coil provided in the actuator 11. Further, the other side of the flexible substrate 24 is connected to this coil by means such as soldering. The pickup main body 21 is formed with a stepped portion 21c that guides the flexible substrate 24. Further, a cover (not shown) is attached to the actuator storage portion 26.

Said flap 4: Since the shiple board 24 is attached to the stepped portion 21c, it will not be pinched by this cover.

Further, optical system members 2 to 4 having substantially the same structure as that shown in FIG. 1 are housed in the optical axis passage.

Among them, the polarizing prism 3 is fixedly attached to three prism holding members, and is inserted into the optical axis passage through a hole 38a bored on one side of the pickup body 21, and is formed on the side of the pickup body 21. Three prism holding members are fixed to the prism mounting portion 38 with screws 40 and 40, thereby positioning them.

Further, the critical angle prism 7 fixed to the side surface of the polarizing prism 3 in the reflection direction is arranged at such a position that the light beam is directed toward the square hole 22d formed in the reinforcing member 22. Further, a similar square hole is bored in the bottom surface of the pickup body 21 corresponding to the square hole 22d, and the light-receiving surface 8a of the photodetector 8, which is divided into four parts, faces this square hole. This photodetector 8 is fixed to a mounting plate 46, and this mounting plate 46 is fixed to the bottom of the pickup main body 21 with screws 47, 47.

In such a configuration, since the pickup body 21 is reinforced by the reinforcing member 22, deformation due to external stress or temperature is reduced, and during assembly, there is sometimes a misalignment between the optical path of the semiconductor laser 1 and the optical axis of the optical system. It never occurs (1s,
Deterioration of optical properties can be prevented.

Further, there is no need to route wiring for the semiconductor laser 1, actuator 11, and photodetector 8, and assembly work can be performed efficiently.

In the illustrated embodiment, the external connection socket portion 22e formed on the reinforcing member 22 protrudes outward from the pickup body 21, but a recess is formed on one side of the pickup body 21, and the above-mentioned External connection socket part 22
If e is housed, there will be no protruding parts from the periphery of the pickup body 21, which not only makes handling easier, but also allows the pickup body 21 to be stored compactly.

[Effect of the Invention 1] As explained above, according to the present invention, a light source is provided on the pickup main body that moves along the recording surface of the recording medium, and a light beam from the light source is irradiated onto the recording surface and the light beam from the recording surface is emitted from the recording surface. An optical system that guides the reflected light to a photodetector and an actuator that corrects the optical system at least two-dimensionally with respect to the recording surface are built in. In addition, since the reinforcing member is integrally formed on the pickup body, it is possible to reduce the weight of aluminum and ensure sufficient rigidity, preventing the pickup body from deforming during assembly, and improving optical characteristics. Deterioration can be prevented.

In addition, this reinforcing member is provided with a conductive pattern connected to the light source, photodetector, and actuator, and an external connection part that is electrically connected to the conductive pattern, eliminating the need for wiring inside the pickup body, which was previously required. This prevents the lead wire from blocking the optical path of the optical system during wiring work, or from being pinched by a cover or the like and causing the lead wire to break.

Furthermore, the wiring for the light source, photodetector, and actuator is minimized, greatly improving assembly work efficiency.

Moreover, it is no longer necessary to provide a space for wiring in the pickup body, and miniaturization can be achieved.

[Brief Description of the Drawings] Figures 1 and 2 relate to an embodiment of the present invention, in which Figure 1 is an exploded perspective view of an optical pickup, Figure 2 is a perspective view of a reinforcing member, and Figure 3 is an optical pickup. Principle diagram showing the operation of pick-ab, 4th
The figure is a perspective view of a conventional big tube body. DESCRIPTION OF SYMBOLS 1... Light source, 2-7... Optical system, 8... Photodetector, O... Recording medium, 10a... Recording surface, 11...
Actuator, 21...Pickup body, 22...
・Reinforcing material, 23c... Electrocardiogram pattern, 22e... External connection agent Patent attorney Susumu Ito Continued from page 1 of Figure 1 Relocated by Isoyou Ordinary location Hatagaya Co., Ltd., Shibuya-ku, Tokyo Inventor Osamu Takabayashi - Hatagaya, Shibuya-ku, Tokyo. No. 2, 2-4, 2011 Olympus Optical Industries, Ltd. No. 2, 2-4, 2013 Olympus Optical Industries procedures? 11 Positive VjJH (Voluntary) January 231, 1985 2. Name of the invention Optical pickup 3. Relationship to the case of those who evade amendment Patent applicant Representative Satoshi Shimoyama Department 4, Agent Address: 160 1. Invention The detailed explanation column has been corrected as follows. 1) Corrected "Figure 33" on page 4, line 10 to "Figure 1, Figure 4." 2) Corrected "Objective lens 7" to "Objective lens 6" on page 5, line 19. 31m 8 U 16th line (7) r23aJ to f23b
J, l"23bJ to "23 a j I; Erotic correction. 2. Corrected "member number 3" in Figure 1 of the drawing as shown in the attached sheet.

Claims (1)

[Claims] A pickup body that moves along the recording surface of a recording medium includes a light source, an optical system that irradiates the recording surface with a light beam from the light source and guides reflected light from the recording surface to a photodetector, and this optical system. In the optical pickup having a built-in actuator for at least two-dimensionally correcting the recording surface, the pickup body is molded from a resin material, and a reinforcing member is integrally formed on the pickup body, The optical pickup further comprises a conductive pattern connected to the light source, the photodetector, and the actuator, and an external connection part electrically connected to the conductive pattern on the reinforcing member.