JPH06186501A - Manufacture of semiconductor laser module - Google Patents

Abstract

PURPOSE:To stabilize the light output of a semiconductor laser module and laser oscillation characteristic by grinding a ferrule end face obliquely after fixing the ferrule on a lens mount in the semiconductor laser module used as the light source of optical communication. CONSTITUTION:The ferrule 29 fixed on an optical fiber 210 in advance is inserted to the lens barrel part of the lens mount 25 on which a lens 22 is fixed in advance, and it is fixed by soldering or welding. After that, the end face of the ferrule 29 is ground obliquely in a certain specific direction for a lens optical axis 23. Thence, a semiconductor laser 21, an optical isolator 24, a photodiode 26 for monitor, and a thermistor 28 are fixed on the lens mount 25. The lens mount 25 is fixed by soldering on a temperature control element 27 fixed by soldering on the bottom of a package 212 in advance. Finally, a gap between the optical fiber 210 and the package 212 is fixed with air tight sealing resin 211, and furthermore, a cover is attached on the package 212 by seam welding, which seals the package from the outside air.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a semiconductor laser module used as a light source for optical communication.

[0002]

2. Description of the Related Art When a semiconductor laser is used as a light source for optical communication, for example, the semiconductor laser is modularized in order to easily take out the laser light output, and the laser output light can be easily obtained from an optical fiber called a pigtail. .

A conventional semiconductor laser module will be described below. FIG. 3 shows the structure of a conventional semiconductor laser module. In FIG. 3, 31 is a semiconductor laser, 32 is light emitted from the semiconductor laser 31, 33 is a lens, 34 is an optical isolator, 35 is a lens mount, and 3 is a lens mount.
6 is a monitor photodiode, 37 is a temperature control element,
38 is a thermistor, 39 is a ferrule, 310 is a ferrule holder, 311 is an optical fiber, 312 is a package, and 313 is sapphire glass.

Here, the end face of the ferrule 39 is the output light 3
2 is obliquely polished to prevent it from being reflected by the end surface and returning to the semiconductor laser 31. When the semiconductor laser 31 emits light, the emitted light 32 is collected by the lens 33,
The light passes through the optical isolator 34, enters the end face of the ferrule 39, and is output from the optical fiber 311. The optical components on the lens mount 35 are kept at a constant temperature by the temperature control element 37.

[0005]

In the conventional semiconductor laser module configured as described above, the position of the pre-diagonally polished ferrule is adjusted so as to increase the coupling efficiency while the semiconductor laser emits light. Weld fixed to the ferrule retainer, and weld the ferrule retainer to the package. As a result, the polishing surface direction and the laser emission optical axis are not always fixed with good reproducibility at the ideal angle position where the coupling efficiency is highest.
When the ambient temperature changes, the ferrule fixing part slightly moves with respect to the laser emission optical axis due to thermal expansion or contraction of the package, and as a result, the incident angle of the laser emission light on the polished surface changes, and the coupling efficiency is increased. However, there is a problem in that the reflected light on the polished surface may return to the semiconductor laser as it is and may greatly affect the oscillation characteristics.

In view of the above, the present invention does not require adjustment of the direction of the ferrule polished surface during assembly, and the ferrule polished surface is always constant with respect to the laser emission optical axis even when the environmental temperature changes. An object of the present invention is to provide a semiconductor laser module having a certain structure.

[0007]

In order to achieve this object, a semiconductor laser module of the present invention comprises a semiconductor laser, at least one lens for converging the emitted light of the semiconductor laser, an optical isolator, and a lens mount. , And an optical fiber for optical output having a ferrule on the incident side, the semiconductor laser, the lens, the optical isolator and the ferrule of the optical fiber are fixed on the lens mount, the ferrule on the lens mount. This is a method for manufacturing a semiconductor laser module that is fixed and then obliquely polished.

[0008]

According to the present invention, due to the above-mentioned structure, it is not necessary to adjust the direction of the ferrule polishing surface at the time of assembly, and the angle formed between the ferrule polishing surface and the semiconductor laser emission optical axis is always constant even when the environmental temperature changes. In addition, it is possible to obtain stable laser oscillation characteristics by stabilizing the optical output and preventing return light.

[0009]

【Example】

(Embodiment 1) An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram of a semiconductor laser module according to the first embodiment of the present invention. First
In the figure, 11 is a semiconductor laser, 12 is light emitted from the semiconductor laser 11, 13 is a lens, 14 is an optical isolator, 15 is a lens mount, 16 is a monitor photodiode, 17 is a temperature control element, 18 is a thermistor, 19
Is a ferrule, 110 is an optical fiber, 111 is a hermetically sealing resin, and 112 is a package. Here, the end surface of the ferrule 19 is fixed to the lens mount 15 and then obliquely polished. The optical fiber 110 is the package 1
The gap with 12 is sealed with an airtight sealing resin 111.

The operation of the semiconductor laser module of this embodiment constructed as above will be described below. When the semiconductor laser 11 emits light, the semiconductor laser 1
The outgoing light 12 from 1 is collected by the lens 13, passes through the optical isolator 14, and enters the optical fiber 110 from the end face of the ferrule 19. At this time, if the environmental temperature changes, the package 112 deforms due to thermal expansion or thermal contraction, but since the optical system on the lens mount 15 is kept at a constant temperature by the temperature control element 17, no optical axis shift occurs. . Therefore, the polishing direction of the end surface of the ferrule 19 is always constant with respect to the optical axis of the emitted light 12.

As described above, according to this embodiment, since the end surface of the ferrule is fixed to the lens mount and then obliquely polished, the polished surface always forms an ideal angle with respect to the laser emission optical axis, and the assembled surface is assembled. At times, it becomes unnecessary to adjust the direction of the polished surface of the ferrule. The angle between the polished surface of the ferrule and the optical axis of the semiconductor laser emission is always constant even when the environmental temperature changes, stabilizing the optical output, and further, the polishing effect of preventing return light to the laser is sufficient. It is possible to obtain stable and stable laser oscillation characteristics.

(Embodiment 2) An embodiment of the present invention will be described below with reference to the drawings.

FIG. 2 is a block diagram of a semiconductor laser module according to the second embodiment of the present invention. In FIG. 2, 21 is a semiconductor laser, 22 is a lens, 23 is a lens optical axis, 24 is an optical isolator, 25 is a lens mount, 26 is a monitor photodiode, 27 is a temperature control element, 28 is a thermistor, 29 is a ferrule, 210 Is an optical fiber, 211 is an airtight sealing resin, and 212 is a package.

The manufacturing method of the semiconductor laser module of this embodiment having the above-described structure will be described below.

The optical fiber 210 is preliminarily attached to the cylindrical portion of the lens mount 25 to which the lens 22 is fixed in advance.
The ferrule 29 fixed to is inserted and fixed by soldering or welding. After that, attach the end face of the ferrule 29 to the lens optical axis 2.
3 is obliquely polished in a specific direction. Next, the semiconductor laser 21, the optical isolator 24, the monitor photodiode 26, and the thermistor 28 are attached to the lens mount 25.
Fix on top. Then, the lens mount 25 is solder-fixed on the temperature control element 26 which is solder-fixed to the bottom of the package 211 in advance. Finally, the gap between the optical fiber and the package is fixed with an airtight sealing resin 211, and a lid is attached to the package 29 by seam welding to seal the package 29 against the outside air.

As described above, according to this embodiment, since the end surface of the ferrule is fixed to the lens mount and then obliquely polished, the polished surface always forms an ideal angle with respect to the laser emission optical axis, and the assembly is performed. At times, it becomes unnecessary to adjust the direction of the polished surface of the ferrule. The angle between the polished surface of the ferrule and the optical axis of the semiconductor laser emission is always constant even when the environmental temperature changes, stabilizing the optical output, and further, the polishing effect of preventing return light to the laser is sufficient. It is possible to obtain stable and stable laser oscillation characteristics.

[0018]

As described above, according to the present invention,
It is not necessary to adjust the direction of the ferrule polishing surface during assembly, and the angle between the ferrule polishing surface and the semiconductor laser emission optical axis can be kept constant even when the environmental temperature changes, and the optical output of the semiconductor laser Stabilization and stabilization of laser oscillation characteristics can be achieved, and its practical effect is great.

[Brief description of drawings]

FIG. 1 is a structural diagram of a semiconductor laser module according to a first embodiment of the present invention.

FIG. 2 is a diagram showing a method of manufacturing a semiconductor laser module according to a second embodiment of the present invention.

FIG. 3 is a structural diagram of a conventional semiconductor laser module.

[Explanation of symbols]

 11 Semiconductor Laser 12 Light Emitted from Semiconductor Laser 12 13 Lens 14 Optical Isolator 15 Lens Mount 16 Monitor Photodiode 17 Temperature Control Element 18 Thermistor 19 Ferrule 21 Semiconductor Laser 22 Lens 23 Lens Optical Axis 24 Optical Isolator 25 Lens Mount 26 Monitor Photodiode 27 Temperature control element 28 Thermistor 29 Ferrule 31 Semiconductor laser 32 Light emitted from semiconductor laser 32 33 Lens 34 Optical isolator 35 Lens mount 36 Monitor photodiode 37 Temperature control element 38 Thermistor 39 Ferrule 110 Optical fiber 111 Airtight sealing resin 112 Package 210 Optical Fiber 211 Airtight Sealing Resin 212 Package 310 Ferrule Holder 311 Optical Fiber 3 12 packages 313 sapphire glass

Claims (1)

[Claims] 1. A semiconductor laser, at least one lens for condensing light emitted from the semiconductor laser, an optical isolator, a lens mount, and an optical fiber for optical output having a ferrule on the incident side. A method for manufacturing a semiconductor laser module, wherein a laser, the lens, the optical isolator, and a ferrule of the optical fiber are fixed on the lens mount, and the ferrule is fixed on the lens mount and then obliquely polished. .