JP2003217134A - Optical pickup device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical pickup device furnished with an optical axis adjusting mechanism having a simple structure to allow the adjustment of the optical axis position of a laser beam. <P>SOLUTION: A laser diode 1 is held on an optical base by using a holder 13. On this holder, the optical axis adjusting mechanism is furnished for adjusting the optical axis position of the laser beam emitted from a semiconductor laser. The optical axis adjusting mechanism may alternatively be constituted of e.g. a neck part 17 formed by applying notched grooves 16 on the holder. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical pickup device using a laser beam emitted from a semiconductor laser.

[0002]

2. Description of the Related Art Recently, an optical disk drive is often mounted on an electronic device such as a personal computer. CD-R (compact disc recordable), CD-R as one of the recording media usable for the optical disc drive
W (compact disc rewritable) is known. CD
-R is a recording medium on which additional recording can be repeated and is a CD-
RW is a rewritable recording medium, but a CD-ROM
It is also compatible with audio CDs (CD-DA). CD
-R, CD-RW requires a dedicated device and writing application to write to CD-R, CD-R
Reading from W can be performed with a normal CD-ROM drive. CD-R, CD-RW, CD-ROM, audio CD, DVD-ROM, DVD-R, DVD-R
The AM and the like are collectively referred to as an optical disc here.

An optical pickup device is used to record and reproduce data on such an optical disc. The optical pickup device includes an optical base movable in the radial direction of the optical disc, a semiconductor laser as a light emitting element held by the optical base, a light receiving element, and an optical system. The semiconductor laser is for generating a laser beam. The light receiving element is for detecting the reflected light from the optical disk. The optical system is for guiding the laser beam or the reflected light from the optical disk.

Holders are used to hold semiconductor lasers on an optical base. When assembling the optical pickup device, the holder is fixed to the optical base while holding the semiconductor laser.

[0005]

Since the degree of spread of the laser beam emitted from the semiconductor laser varies depending on the direction, the optical axis of the optical system fixed to the optical base and the optical axis of the laser beam emitted from the semiconductor laser are different from each other. It is necessary to adjust the optical axis position so that The position of the optical axis can be adjusted by adjusting the relative positional relationship between the optical base and the holder.

However, an optical axis adjusting mechanism having a complicated structure is required to adjust the relative positional relationship. Moreover, when the optical pickup device is assembled or after that, it is necessary to perform a fine operation on the optical axis adjusting mechanism,
Work is not easy.

Therefore, an object of the present invention is to provide an optical pickup device provided with an optical axis adjusting mechanism having a simple structure that enables adjustment of the optical axis position of a laser beam.

Another object of the present invention is to provide an optical pickup device capable of adjusting the optical axis position of a laser beam before assembling the optical pickup device.

[0009]

According to the present invention, an optical pickup device including an optical base (10), a semiconductor laser (1), and a holder (13) holding the semiconductor laser on the optical base. In the optical pickup device, the holder is provided with an optical axis adjusting mechanism (16, 17) for adjusting the optical axis position of the laser beam emitted from the semiconductor laser.

The holder has a holding portion (14) holding the semiconductor laser and a fixing portion (15) fixed to the optical base, and the optical axis adjusting mechanism holds the holding portion with respect to the fixing portion. Neck part (17) with tiltable parts
May have.

The neck portion may be a portion left between the pair of cut grooves (16) formed between the holding portion and the fixing portion.

An angle fixing means (19) for fixing the angle of the holding portion with respect to the fixing portion may be provided.

The angle fixing means may be an adhesive (19) that adheres the fixing portion and the holding portion to each other.

The reference numerals in the above parentheses are given for easy understanding and are merely examples, and the present invention is not limited to these.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An outline of an optical pickup device according to an embodiment of the present invention will be described with reference to FIG.

The illustrated optical pickup device can be used in an optical disk drive mounted in an electronic device such as a personal computer, and uses a laser diode 1 which is a semiconductor laser for generating a laser beam as a light emitting element. The laser beam emitted from the laser diode 1 is branched by the beam splitter 2, and a part of the laser beam is incident on the monitor device 3. The other part of the laser beam irradiates the optical disk 7 through the collimator lens 4, the rising mirror 5 and the objective lens 6. The monitor device 3 detects the intensity of the laser beam. The detected intensity is used to control the driving of the laser diode 1. In this way, data can be recorded on the optical disk 7 using the laser beam emitted from the laser diode 1.

The reflected light from the optical disk 7 enters a photodiode 8 as a light receiving element through the objective lens 6, the rising mirror 5, the collimating lens 4, the beam splitter 2, and the like. In this way, the optical disk 7 is produced by using the laser beam emitted from the laser diode 1.
You can play the data from.

The optical pickup device will be described in detail with reference to FIG. 2 in addition to FIG.

A beam splitter 2, a collimator lens 4, a rising mirror 5, which are arranged in the path of the laser beam,
Also, various optical elements such as the objective lens 6 are collectively referred to as an optical system here. The optical system, the laser diode 1, the monitor device 3, and the photodiode 8 are held by an optical base 10 which is a device housing. The optical base 10 is movably mounted on the optical disk drive using the guide hole 11.

Most of the optical base 10, in particular, the diode mounting portion 12 is made of a metal having a high thermal conductivity. The laser diode 1 is fixed to the diode mounting portion 12 by the holder 13.

The holder 13 will be described in detail with reference to FIGS. 3 and 4.

The holder 13 is made of plastic or a metal material which is easily plastically deformed (eg, zinc),
It has a holding portion 14 for holding the laser diode 1 and a fixing portion 15 for fixing the laser diode 1 to the optical base 10. A pair of cut grooves 16 are formed symmetrically between the holding portion 14 and the fixed portion 15. Pair of notches 16
The portion left between the two is called a neck portion 17 here. The neck portion 17 has flexibility, and the holding portion 14 is tiltably connected to the fixed portion 15. The tilting angle range of the holding portion 14 is limited by the width of the cut groove 16.
The cut groove 16 and the neck portion 17 together serve as an optical axis adjusting mechanism.

Before fixing the holder 13 to the diode mounting portion 12, the laser diode 1 is fitted into the recess 18 of the holding portion 14 as shown by an arrow A1 in FIG. Mounted with. After mounting the laser diode 1, the holding portion 14 is attached to the fixing portion 15.
Is tilted to the left or right as necessary to adjust the direction of the laser diode 1, that is, the optical axis position of the laser beam. At this time, the holding portion 14 tilts with the neck portion 17 as a fulcrum.

After adjusting the optical axis position of the laser beam to a desired position, as shown in FIG. 4, an adhesive 19 is applied to the inside of the cut groove 16 or in the vicinity thereof to fix the holding portion 14 to the fixing portion 15. The adhesive 19 is used to bond and fix. This adhesion may be applied only to a part of the cut groove 16, but may be applied to both ends, or may be applied to the whole between both ends. In this way, the relative angle between the fixed portion 15 and the holding portion 14 is fixed. In this case, the adhesive 19 acts as an angle fixing means.

After fixing the holding portion 14 to the fixing portion 15, the fixing portion 15 of the holder 13 is firmly fitted and fixed to the diode mounting portion 12 of the optical base 10 in the same manner as in the conventional case. Since the optical axis position of the laser beam with respect to the fixed portion 15 is adjusted in advance, there is no need to adjust the optical axis position during or after assembling the optical pickup device. Therefore, productivity can be improved by reducing the number of assembly steps. Further, since the above-mentioned optical axis adjusting mechanism does not accompany the increase in the number of parts, it is possible to reduce the number of parts and the cost of the optical pickup device. Since no special mechanism or device for adjusting the optical axis position is required when assembling the optical pickup device, the optical pickup device can be downsized.

In the above description, the holder 13 is replaced with the diode mounting portion 1.
The case where the optical axis position is adjusted before being fixed to 2 is described, but after fitting the fixing portion 15 of the holder 13 to the diode mounting portion 12 as shown in FIG. Alternatively, the optical axis position may be adjusted by tilting the holding portion 14 of the holder 13 as shown by the arrow A2 (exaggerated in FIG. 5B). In that case, the fixing portion 15 may be fixed to the diode mounting portion 12 before the adjustment of the optical axis position, or may be fixed after the adjustment of the optical axis position.

Incidentally, the diode mounting portion 12 and the fixing portion 15
The fixing may be performed by using one or a plurality of fixing jigs made of leaf springs, which are separate components, or may be performed by using an adhesive.

[0028]

As described above, according to the present invention,
Provided is an optical pickup device having a simple structure capable of adjusting the optical axis position of a laser beam and having an optical axis adjusting mechanism capable of adjusting the optical axis position of a laser beam before assembling the device. be able to.

[Brief description of drawings]

FIG. 1 is an explanatory diagram for explaining an outline of an optical pickup device according to an embodiment of the present invention.

FIG. 2 is a perspective view specifically showing the optical pickup device of FIG.

3 is a perspective view showing a disassembled state of a laser diode and a holder used in the optical pickup device of FIG.

FIG. 4 is a perspective view showing a state after the laser diode and the holder of FIG. 3 are fixed to each other and the optical axis position is adjusted.

5A and 5B are views for explaining a case where an optical axis position is adjusted after mounting a laser diode on an optical base, FIG. 5A is a schematic plan view showing a state before adjustment, and FIG. It is a schematic plan view which shows the state of.

[Explanation of symbols]

1 laser diode 2 beam splitter 3 Monitor device 4 Collimating lens 5 Launch mirror 6 Objective lens 7 Optical disc 8 photodiodes 10 Optical base 11 Guide hole 12 Diode mounting part 13 Holder 14 Holder 15 Fixed part 16 notch 17 Neck 18 recess 19 adhesive

   ─────────────────────────────────────────────────── ─── Continued front page    F term (reference) 5D117 AA02 CC07 HH01 KK01 KK21                       KK23 KK25                 5D119 AA01 AA04 AA38 BA01 BB01                       BB02 BB04 FA35 FA37 NA04                 5D789 AA01 AA04 AA38 BA01 BB01                       BB02 BB04 FA35 FA37 NA04

Claims (5)

[Claims] 1. An optical pickup device including an optical base, a semiconductor laser, and a holder that holds the semiconductor laser on the optical base, wherein the holder is configured to set an optical axis position of a laser beam emitted from the semiconductor laser. An optical pickup device comprising an optical axis adjusting mechanism for adjusting. 2. The holder has a holding portion holding the semiconductor laser and a fixing portion fixed to the optical base, and the optical axis adjusting mechanism can tilt the holding portion with respect to the fixing portion. The optical pickup device according to claim 1, further comprising a neck portion coupled to the. 3. The optical pickup device according to claim 2, wherein the neck portion includes a portion left between the pair of cut grooves formed between the holding portion and the fixing portion. 4. The optical pickup device according to claim 2, further comprising an angle fixing unit that fixes an angle of the holding unit with respect to the fixing unit. 5. The optical pickup device according to claim 4, wherein the angle fixing means is an adhesive that bonds the fixing portion and the holding portion to each other.