JPH01238612A - Laser light source device - Google Patents

Abstract

PURPOSE:To substantially eliminate the influence of oscillations, impact and temp. fluctuations and to supply a stable beam by pouring an adhesive agent through injection ports and fixing a collimator lens and collimator lens barrel from plural directions thereby fixing the lens and lens barrel. CONSTITUTION:The collimator lens 1b and a semiconductor laser 1a are adjusted within the Y-Z plane and in the X direction which is the optical axis direction; thereafter, the instantant-set adhesive agent is injected through the injection port 1k of the collimator lens barrel 1d to adhere the lens and the lens barrel. Although the port 1k is connected to the adhesive grooves 1j in the collimator lens barrel 1d, the spreading of the adhesive agent is not sufficient in some cases on account of the viscosity of the adhesive agent, the depth of the grooves, etc. Two pieces of the injection ports 1k are, thereupon, provided and the adhesive agent 1l is injected from the two directions. The lens and lens barrel are then adhered from the two directions even if the spreading of the adhesive agent 1l is half round or below and, therefore, the quantity at which the collimator lens 1b is moved within the lens barrel 1d by the oscillations, fall and temp. fluctuations is extremely lessened.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a laser light source device used in an optical information recording/reproducing device such as an optical disc.

[Conventional technology]

Collimator lenses have conventionally been used to collimate a laser beam output from a semiconductor laser.

The semiconductor laser and the collimator lens are usually assembled into the same unit, which is called a collimator unit.

The adjustment principle of a conventionally used collimator unit will be explained with reference to FIG. Normally, adjustment is required to convert the diffused light of the semiconductor laser 1a into parallel light via the collimator lens 1b. The semiconductor laser 1a is shown on the coordinate axis YZZn.
The three-collimator lens 1b is adjusted in the coordinate axis X direction. Furthermore, FIG. 5 shows a cross-sectional view of a commonly used collimator unit. 1b is a collimator lens that converts laser light into parallel light, If is a coil spring that always presses collimator lens ib in the direction of the arrow shown in the figure, ld is a collimator lens barrel that holds coil spring 1f and collimator lens 1b, and holding ring 1e is a collimator lens. It is engaged with the lens barrel 1d with a screw. 1a is a semiconductor laser which is a light source;
lc is a laser spacer holding the semiconductor laser la, 1h is a screw (1) for connecting the laser spacer 10 to the collimator lens barrel 1d via a washer 1g, and 11 is a collimator lens lb and the semiconductor laser 1a. This is a screw (2) for engaging a collimator unit including a collimator unit with an optical head of an optical information recording/reproducing device.

The collimator lens 1b is subjected to a force in the direction of the arrow shown in the figure by a coil spring 1f housed in the collimator lens barrel 1d. Further, the holding ring 1e is engaged with a screw cut at the tip of the collimator lens barrel 1d, and receives the force of the coil spring 1f via the collimator lens 1b in the optical axis direction (X-axis) of the collimator lens lb. determining the position. Therefore, by rotating this presser ring 1e, the position of the collimator lens 1b is moved in the optical axis direction, the distance from the semiconductor laser 1a is adjusted, and the laser beam is converted into parallel light. Further, the laser spacer 10 holding the semiconductor laser 1a is adjusted in the YZ force directions shown in FIG. 4 between the laser spacer 10 and the collimator lens barrel 1d.

When the adjustment is completed, the collimator lens 1b and the collimator lens barrel 1d are bonded together. At this time, adhesive is injected into the adhesive groove IJ from the injection port 1k. As shown in FIG. 6, the adhesive dropped from the adhesive injection port 1k often did not extend around the inner diameter of the collimator lens barrel. If the adhesive 11 does not wrap around the entire circumference, especially if it is less than half the circumference, the adhesive 1β may cause the collimator lens 1b to connect with the collimator lens barrel 1d due to changes in temperature, vibration, or impact. This results in a tilt movement corresponding to the clearance of the lens 1b, causing a problem in that the beam moves on the sensor of the optical head.

[Summary of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to eliminate the drawbacks of the conventional devices described above, and to provide a laser light source device that is not susceptible to fluctuations in temperature, vibrations, shocks, etc., and can always supply a stable beam.

The above object of the present invention is characterized in that a collimator lens facing a laser light source is held by a lens mount, and the lens mount is provided with a plurality of injection ports through which adhesive is poured in order to fix the collimator lens to the lens mount. This can be achieved using a laser light source device.

〔Example〕

FIG. 1 shows a cross-sectional view of a collimator unit that is an embodiment of the present invention. Collimator lens 1b and semiconductor laser l
As for the adjustment of a, the adjustment within the 72 plane shown in Fig. 4,
Adjustments are made in the X direction, which is the optical axis direction. A specific method for this adjustment is the configuration shown in FIG. 5 (description will be given as a conventional example).

After completing the adjustment, use adhesive, especially instant adhesive (viscosity is 3~5c).
(approx. p) is injected from the injection port 1k. This injection port 1 is connected to the adhesive groove IJ in the collimator lens barrel 1d, but the adhesive's viscosity, groove depth, and surface condition of the inner diameter of the collimator lens barrel and the inner diameter of the collimator lens barrel may vary. The surroundings will be different. Adhesive l that goes around the adhesive groove 1j! As shown in FIG. 2, two injection ports 1k are provided to inject from two directions. This allows the adhesive li! Even if the circumference of the collimator lens 1b is less than half a circle, the adhesive 11 is injected from two directions, especially from the 180° direction, and the collimator lens 1b is bonded.
However, the eclipse moving within the collimator lens barrel 1d has become very small.

Furthermore, as shown in FIG. 3, four injection ports 1k are provided,
Adhesive 1k is injected from four directions. Alternatively, four injection ports 1k may be provided to inject the adhesive 11 from two directions (particularly from the 180° direction), and the other two injection ports 1 may be used as an escape for the air in the adhesive groove IJ. . What has been explained above is for two or four injection ports 1, but it is also possible to use three or four or more injection ports. It is highly effective if the injection points are also in two directions, especially in the 180° direction.

〔Effect of the invention〕

As explained above, by bonding the collimator lens and collimator lens barrel from multiple directions, changes in the angle of parallel light emitted from the collimator unit due to vibrations, drops, and temperature changes are reduced, allowing optical information recording and reproduction. When used in an optical head of a device, the reliability of focus and tracking control is improved, as well as the reliability of data.

Furthermore, when used in an optical scanning device such as an LBP, it is possible to provide a highly precisely shaped beam onto a scanned medium.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing a collimator unit according to an embodiment of the present invention, and FIG. 2 is a schematic diagram showing the collimator unit shown in FIG.
A' sectional view, FIG. 3 is a sectional view of a collimator unit according to another embodiment of the present invention, FIG. 4 is a principle diagram of collimator adjustment, FIG. 5 is a schematic diagram showing a conventional collimator unit, and FIG. 6 is a sectional view of a collimator unit according to another embodiment of the invention. It is a BB' sectional view of the fifth illustrated collimator unit. la・・・・・・・・・・・・・・・・・・・・・
...... Semiconductor laser 1b ・
・・・・・・・・・－・・ ・・・・・・・・・・・・・・・
・・・・ Collimator lens 1c ・・・・・・・・
・・・・・・・・・・・・・・・ Racer spacer-1d ・・・・・・ ・・・・・・・・・ Collimator lens barrel 1e・・・・・・・・・・・・・・・・・・
・・・・・・・・・・・・・・・・・・・・・・・・
・・Presser ring 1f・・・・・・・・・・・・・・・・・
・・・・・・・・・・・・・・・・・・・・・・・・ Coil spring 1g・・・・・・・・・・・・・・・・・・・・・
・・・・・・・・・・・・・・・・・・Washer lh・・・・・・・・・・・・・・・・・・・
・・・・・・・・・・・・・・・・・・Screw (1
)11・・・・・・・・・・・・・・・・・・・・・
・・・・・・・・・・・・・・・・・・・・・・・・
・Screw (2) IJ・・・・・・・・・・・・・・・
・・・・・・・・・・・・・・・・・・・・・・・・
・・・・・・・・・Adhesive groove 1k・・・・・・・・・・・・
・・・・・・・・・・・・・・・・・・・・・・・・
・・・・・・・・・・・・ Inlet/system/water

Claims (1)

[Claims] (1) A laser light source device characterized in that a collimator lens facing the laser light source is held by a lens mount, and the lens mount is provided with a plurality of injection ports through which adhesive is poured in order to fix the collimator lens to the lens mount. .