KR100561871B1 - Optical pickup - Google Patents

Abstract

An optical pickup apparatus is disclosed. The optical pickup apparatus according to the present invention has a plate-shaped optical bench in which a mount insertion hole is formed at one side, a heat sink coupled to the optical bench, and integrally formed at the heat sink, and having a predetermined height fitted into the mount insertion hole of the optical bench. And a light source mounted on an upper surface of the mount.

Description

Optical pickup apparatus

1 is a perspective view showing an optical pickup device according to an embodiment of the present invention.

FIG. 2 is a side view of the optical pickup device of FIG. 1. FIG.

3 is a perspective view illustrating the optical bench and the heat sink of FIG.

4 is an exploded perspective view of FIG. 3.

<Description of Symbols for Major Parts of Drawings>

10: Optical bench 11: Mount insertion hole

13: First light pass 15: Main photodetector

17: wiring 18: pad

19: monitor photodetector 20: heat sink

22: Mount 23: second light pass

25: light source 30: lens unit

40: mirror portion 40a: first mirror

40b: second mirror 50: optical path separator

100: information storage medium

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical pickup apparatus, and more particularly, to an optical pickup that can reduce the number of alignment and bonding processes for disposing a light source, and easily arranges a light source on a designed optical path. Relates to a device.

In general, optical pickup is employed in optical recording and reproducing apparatuses such as CDP, CD-ROM, DVDP, DVD-ROM, BD (Blue-ray Disk), and the like to record information on the optical disk in a non-contact manner while moving in the radial direction of the optical disk. / Or perform playback.

Recently, as optical recording and reproducing apparatuses are widely adopted in personal digital assistants (PDAs), portable MP3 players, portable CDPs, and the like, optical pickups capable of miniaturization, thinning, and high density information recording / reproducing are required.

Conventional optical pickup includes a light source, a submount (Simount), an optical bench (Si optical bench), a photo detector, a lens unit, and the like, and LD chip (Laser Diode chip) is mainly used as a light source.

The position of these optical components in the optical pickup device depends on the optical path being designed, and the alignment and bonding of the optical components on the optical path has a great influence on the precision and reproducibility of the manufactured optical pickup device. .

Conventionally, submounts have been used for the purpose of quickly dissipating heat generated from LD chips and for disposing LD chips in an optical path. To this end, the conventional optical pickup apparatus has a structure in which a submount is disposed on an optical bench and an LD chip is disposed on the submount.

In the structure of such an optical pickup device, two alignment processes and two bonding processes are required to arrange the light source on the designed optical path. Specifically, an alignment process and a bonding process required when arranging the submount on the optical bench, and an alignment process and bonding process required when the LD chip is disposed on the submount are required. Therefore, there is a problem that a lot of time is required in manufacturing the optical pickup device.

In addition, in the two alignment processes and the two bonding processes, there is a problem in that poor alignment of the LD chip is likely to occur during the manufacturing process of the optical pickup device, and a burden of the assembly tolerance due to the bonding process is large.

Due to the complexity of the manufacturing process, a decrease in productivity, poor alignment of the light source, and the like, limitations on the miniaturization of the optical pickup apparatus have been encountered, and improvements in the structure of the conventional optical pickup apparatus have been required.

The technical problem to be achieved by the present invention is to improve the above-described problems of the prior art, it is possible to reduce the number of alignment and bonding processes for the arrangement of the light source, It is easy to deploy, and to provide an optical pickup device more accurate and reproducible.

In addition, the problem of heat generation that occurs when the light source is disposed on the optical bench that does not have a high thermal conductivity in the related art is solved, to provide an optical pickup device that can effectively emit heat generated from the light source.

According to the present invention, a plate-shaped optical bench having a mount insertion hole formed on one side, a heat sink coupled to the optical bench, and integrally formed in the heat sink, for mounting a light source having a predetermined height fitted into the mount insertion hole of the optical bench An optical pickup apparatus having a mount and a light source mounted on an upper surface of the mount is provided.

Hereinafter, an optical pickup apparatus according to the present invention will be described in detail with reference to the accompanying drawings.

1 is a perspective view showing an optical pickup device according to an embodiment of the present invention, Figure 2 is a side view of the optical pickup device of FIG. 3 is a perspective view illustrating the optical bench and the heat sink of FIG. 1, and FIG. 4 is an exploded perspective view of FIG. 3.

2 to 4 together, the optical pickup device according to an embodiment of the present invention is coupled to the plate-shaped optical bench 10, the optical bench 10, the mount insertion hole 11 is formed on one side The heat sink 20, the mount 22 formed integrally with the heat sink 20 and fitted into the mount insertion hole 11 of the optical bench 10, and the light source 25 mounted on the top surface of the mount 22. Equipped with. The optical pickup apparatus further includes a lens unit 30, a mirror unit 40, and an optical path separating unit 50.

The optical bench 10 is provided with a first light passing hole 13 through which light from the light source 25 passes, and the heat sink 20 has a second light corresponding to the first light passing hole 13. The light passing hole 23 is provided.

The light emitted from the light source 25 passes through the first light through hole 13 provided in the optical bench 10 and the second light through hole 23 provided in the heat dissipation plate 20 to store the information storage medium 100. The light reflected from the information storage medium 100 may be incident to the first mirror 40a.

In addition, a main photodetector 15 and a monitor photodetector 19 are provided on one surface of the optical bench 10. The monitor photodetector 19 directly receives a portion of the light emitted from the light source 25 to generate a signal for monitoring the light amount of the light source 25.

The main photodetector 15 receives the light reflected from the information storage medium 100 to receive an information reproduction signal (RF signal) and an error signal (eg, a focus error signal, a tracking error signal and / or a signal used for servo driving). Tilt error signal) is detected.

The lens unit 30 focuses the light incident from the light source 25 to form a light spot on the information storage medium 100. The lens unit may include at least one of a refractive lens, a diffractive lens, and a green lens.

The mirror unit 40 is provided at one side of the optical bench 10 to reflect the light from the light source 25 to the first light passing hole 13 and the second light passing hole 23 to store an information storage medium. The main photodetector (1) provided at the first mirror (40a) and incident on the other side of the optical bench (10) and reflected from the information storage medium (100) and transmitted from the first mirror (40a) 15, the second mirror 40b is incident.

The optical path separation unit 50 separates a path of light emitted from the light source 25 and incident on the information storage medium 100 and a path of light reflected from the information storage medium 100. For example, the optical path separator 50 may include a diffractive optical element, that is, a hologram optical element (HOE) or a diffractive optical element (DOE).

Therefore, the optical path separating unit 50 transmits the light directed to the information storage medium 100 in a straight line and diffracts the light reflected from the information storage medium 100 to separate the light path. Specifically, the light reflected from the information storage medium 100 and diffracted by the optical path separation unit 50 proceeds obliquely with respect to light traveling toward the information storage medium 100, and finally the main light. The detector 15 receives light.

3 and 4 together, the heat dissipation plate 20 provided with the light source 25 mounting mount 22 is coupled to the plate-shaped optical bench 10 having the mount insertion hole 11 formed on one side thereof, The light source 25 is mounted on the upper surface of the mount 22.

Therefore, the light source 25 mounted on the mount 22 is spaced apart from the bottom surface of the optical bench 10 by a predetermined distance, so that the light source 25 can be easily disposed on the designed light path.

In addition, the heat sink 20 is made of one body with the mount 22 by a molding, injection, etching or lithography process, the heat sink 20 is made of a thermally conductive material.

The optical pickup apparatus according to the present invention adopts a structure in which an optical bench having a mount insertion hole formed therein and a heat sink provided with a light source mounting mount fitted to the mount insertion hole are combined to self-align the mount on the optical bench. Made it possible.

Therefore, in the optical pickup apparatus of the present invention, since the mount is auto aligned on the optical bench, the alignment process of the mount is not required on the optical bench, and the light source can be easily disposed on the designed optical path. .

In the conventional optical pickup apparatus, a submount is disposed on an optical bench and an LD chip is disposed on the submount, so that two alignment processes and two bonding processes are performed to arrange the light source on the designed optical path. There was a problem that it is required, but the optical pickup device according to the present invention has improved such problems efficiently.

The optical pickup device according to the present invention is manufactured by one alignment process and bonding process between the optical bench and the light source to which the heat sink is coupled to arrange the light source on the designed optical path, and the manufacturing process is simplified. Can be.

Therefore, a more precise and reproducible optical pickup device can be manufactured, while the manufacturing cost can be reduced. In addition, since the light source is easily disposed on the designed optical path, the burden of the assembly tolerance due to the alignment process and the bonding process can be reduced, and the optical pickup apparatus can be manufactured with precision and reproducibility.

The heat sink is made of a mount and one body by a molding, injection, etching or lithography process, and since the heat sink is made of a thermally conductive material, it effectively releases heat generated from the light source.

A wiring 17 and a pad 18 are provided on one surface of the silicon optical bench (SiOB) to electrically connect the main photodetector 15 and the monitor photodetector 19 to an external circuit.

While many details are set forth in the foregoing description, they should be construed as illustrative of preferred embodiments, rather than to limit the scope of the invention. The scope of the invention should not be defined by the described embodiments, but should be determined by the technical spirit described in the claims.

The optical pickup device according to the present invention is manufactured by one alignment process and bonding process between the optical bench and the light source to which the heat sink is coupled to arrange the light source on the designed optical path, and the manufacturing process is simplified. Can be.

Therefore, the burden of assembly tolerances according to the alignment process and the bonding process can be reduced, and a more precise and reproducible optical pickup device can be manufactured, while manufacturing costs can be reduced.

 In addition, since heat generated in the light source can be effectively released through the heat sink, deterioration of the light source can be prevented and the life of the light source can be extended.

Claims (8)

A plate-shaped optical bench having a mount insertion hole formed at one side thereof; A heat sink coupled to the optical bench; A mount having a predetermined height formed integrally with the heat sink and fitted into a mount insertion hole of the optical bench; And And a light source mounted on an upper surface of the mount. The method of claim 1, The heat sink formed integrally with the mount is an optical pickup device, characterized in that manufactured in a single unit by a molding process. The method of claim 1, And the heat sink formed integrally with the mount is fabricated as a single piece by a lithography process. The method of claim 1, And a first light passing hole through which the light from the light source passes through the optical bench. The method of claim 4, wherein And a second light through hole corresponding to the first light through hole in the heat sink. The method of claim 5, And a monitor photodetector for directly receiving a portion of the light emitted from the main photodetector and the light source on one surface of the optical bench. The method of claim 6, A first mirror provided at one side of the optical bench to reflect light from the light source to the first and second light passing holes and incident to the information storage medium, and provided at the other side of the optical bench and reflected from the information storage medium; And a second mirror for incident the reflected light transmitted from the first mirror to the main photodetector. The method of claim 1, And an optical path separation unit configured to separate a path of the light emitted from the light source to the information storage medium and a path of the light reflected from the information storage medium on one side of the optical bench.

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