JPH0654824B2 - Array type semiconductor laser device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a light source device using a semiconductor laser, and more particularly to an array type laser device.

(Prior Art) Since a semiconductor laser is small, it is widely used as a light source for an optical disk device or the like instead of a gas laser. Further, in recent years, an array type semiconductor laser provided with a plurality of light sources capable of being independently driven has been developed. By using such a laser, it is possible to obtain better characteristics than the conventional device, and for example, the data transfer speed is increased in the optical disk device.

In an array type semiconductor laser, it is practically important not only to drive each light emitting source independently but also to monitor the output of the light emitting source independently. It is conceivable to form an image of the light emission output through a lens system and monitor the output of each light emission source at the image formation point, but this system requires an optical system, resulting in an increase in size of the light source.

FIG. 5 is a perspective view showing a conventional monitor type array type semiconductor laser device. The light-receiving surface 6 is formed in advance on the heat sink substrate 1, and the array type semiconductor laser 2 is installed as shown in the figure. The output from each light emitting source 7 is received by each light receiving surface and the output is monitored. FIG. 6 is a side view showing another conventional monitor type array type semiconductor laser device. In this method, an array-type detector 3 having a plurality of light-receiving surfaces 6 is installed in proximity to the back surface of the array-type semiconductor laser 2 provided on the heat sink substrate 1.

(Problems to be Solved by the Invention) In the example of FIG. 5, since the light receiving surface 6 is provided on the heat sink substrate 1, a metal or the like used as an adhesive when the array type semiconductor laser 2 is bonded to the heat sink substrate 1 is used. It is necessary to take care so that the light does not overflow on the light receiving surface 6. Further, when the laser electrode 5 for independently driving each laser is provided on the heat sink substrate 1, the width of the extracted electrode is limited so as not to overlap the light receiving surface 6. Since a semiconductor laser usually requires a current of several tens to 100 mA or more, if the electrode is thin, it will be affected by the electrode resistance value.

Further, in the example of FIG. 6, the light receiving surface 6 is parallel to the laser emitting end surface.
Is provided, the reflected light from the light-receiving surface 6 returns to the laser, making the output level and noise characteristics unstable.

The object of the present invention does not cause the above problems. To obtain an array type semiconductor laser device with a monitor function.

(Means for Solving Problems) An array type semiconductor laser device of the present invention includes a heat sink substrate, an array type semiconductor laser having a plurality of light emitting sources,
The array type semiconductor laser has a light emitting source and an array type detector having independent light receiving surfaces at substantially equal intervals, and the array type semiconductor laser is installed on an upper surface of the heat sink substrate. One side of the array type semiconductor laser The array-type detector is arranged so that the light receiving surface and the upper surface of the heat sink substrate face each other with a predetermined gap close to the end face, and the light emitting position of the semiconductor laser exists within the predetermined gap. Is installed.

(Operation) FIG. 2 is a side view showing a basic configuration example of the present invention. The array-type detector 3 is installed so that the light-receiving surface 6 faces downward and is spaced apart from the heat sink substrate 1. The height of the light receiving surface 6 is
It may be above the light emission source 7 of the array type semiconductor laser 2. Part of the light emitted from the end face of the laser is absorbed by the light receiving surface 6, and the rest is reflected by the lower surface of the detector 3 on the upper surface of the heat sink substrate 1. With the arrangement according to the present invention, since the reflected light does not return to the light emitting source, the output can be monitored without making the laser output unstable. As shown in FIG. 3, the light receiving surface 6 and the upper surface of the heat sink substrate 1 do not have to be parallel to each other, but may be at an angle at which emitted light does not return to the light emitting source.

FIG. 4 is a plan view showing the position of the light receiving surface 6 with respect to the laser emission light in the array type semiconductor laser device of FIG. By providing the light receiving surface at a position where the emitted lights from the respective light emitting sources do not overlap, the emitted lights can be independently received.
Although this figure shows an example of four arrays, the present invention does not limit the number of arrays. Even if the arrays are evenly spaced, each emitted light can be independently received in principle in the same manner.

(Embodiment) FIG. 1 is a perspective view showing an embodiment of the present invention. In this embodiment, an array type semiconductor laser 2 and an array type detector 3 are provided on a heat sink substrate 1 via a spacer 4. Since the laser electrode 5 can be provided below the light receiving surface of the detector 3, it is possible to secure a sufficient width. The bonding position to the electrode 5 should be as lateral as possible to avoid scattered light.

The structure for holding the detector 3 is not limited to the implementation.
For example, the surface of the detector 3 may be previously provided with irregularities to serve as spacers. Further, a spacer having a light blocking effect may be provided between the light receiving surfaces to further reduce crosstalk from adjacent light emitting sources.

The electrodes of the detector 3 may be configured to be guided onto the heat sink substrate 1 via the spacer.

(Effects of the Invention) According to the present invention, it is possible to obtain an array type semiconductor laser device that can be independently monitored without affecting the laser characteristics.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of the present invention, and FIGS.
FIG. 5 is a diagram for explaining the configuration of the present invention, and FIGS. 5 and 6 are diagrams showing a conventional example. 1 ... Heat sink substrate, 2 ... Array type semiconductor laser, 3 ... Array type detector, 4 ... Spacer, 5 ...
... laser electrode, 6 ... light receiving surface, 7 ... light emitting source.

Claims (1)

[Claims] 1. A heat sink comprising: a heat sink substrate; an array type semiconductor laser having a plurality of light emitting sources; and an array type detector having an independent light receiving surface at substantially the same intervals as the light emitting sources of the array type semiconductor laser. The array type semiconductor laser is installed on the upper surface of the substrate, and the light receiving surface and the upper surface of the heat sink substrate face each other with a predetermined distance in close proximity to one end surface of the array type semiconductor laser, and An array type semiconductor laser device, wherein the array type detector is installed so that a light emitting position of the semiconductor laser exists within the predetermined interval.