JPH05241045A - Optical module - Google Patents

Abstract

PURPOSE:To enable joining of sub-modules constituting optical modules, such as waveguide type optical circuit parts, semiconductor modules and photodetecting modules, to each other without allowing the infiltration of the slag generated at the time of welding between the end faces of the sub-modules. CONSTITUTION:Barrier walls 48, 50 are provided between welding surfaces 40 of a metallic block 18 of the waveguide type circuit parts 12 and a metallic block 24 of input fiber parts 14 and welding surfaces 42 of the metallic block 18 of the waveguide type circuit parts 12 and a metallic block 26 of output fiber parts 16 as well as optical connecting surfaces 44, 46 of the waveguide element 22 and fiber arrays 28, 30. These barrier walls 48, 50 consist of level differences formed between these surfaces. Then, the slag generated at the time of welding the parts to each other is shut off by the level differences and do not arrive at the optical connecting surfaces.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of an optical module such as a waveguide type optical circuit component, a semiconductor laser and a light receiving module, and more particularly to an optical module having an improved connection between submodules.

[0002]

2. Description of the Related Art When a waveguide type optical circuit component is mentioned as an example of an optical module, the waveguide type optical circuit component is, as shown in FIGS. 7 and 8, a waveguide circuit component 12 and this waveguide circuit component. Input / output fiber component 1 joined to both ends of 12
4 and 16, and these submodules are bonded in an aligned state. The waveguide road circuit component 12 comprises a chip-shaped waveguide element 22 adhered to a metal block 18 by a lid 20, and the input / output fiber components 14 and 16 are composed of the metal block 2.
Fiber array 2 bonded and fixed to 4 and 26, respectively
It consists of eight and thirty.

An end face of a part 12 which is a sub-module and 1
The end faces of 4 and 16 are flat-polished. These sub-modules are arranged so that the flat-polished end faces are butted against each other, and the core of the waveguide element 22 and the cores of the fiber arrays 28 and 30 are aligned with each other. As shown in FIG. 8, lasers emitted from a plurality of YAG laser heads 32, 34, 36, 38 are laterally applied to the welding surface of the sub-module to join the sub-modules.

[0004]

When welding the sub-modules of the waveguide type optical circuit component of this prior art with a YAG laser, there is a slight gap between the end face of the waveguide circuit component and the end face of the fiber array. If so, the slag generated at the time of welding penetrates between the both end surfaces to prevent light from being transmitted, so that there is a drawback that the transmission loss of the joint portion becomes large. On the other hand, it was extremely difficult to abut the end faces between the two parts without leaving a gap. Incidentally, this applies not only to the waveguide type optical circuit component but also to other optical modules such as a semiconductor laser and a light receiving module.

It is an object of the present invention to provide an optical module which avoids the above-mentioned drawbacks and allows sub-modules to be joined to each other without intrusion of slag generated during welding between the end faces of the sub-modules. It is in.

[0006]

In order to solve the above-mentioned problems, the present invention comprises a plurality of sub-modules each comprising a metal block and a sub-module body adhered and fixed in the metal block, and adjacent sub-modules. In an optical module in which the sub-module bodies are abutted against each other by adhesively fixing the metal blocks to each other and connected to each other, a barrier is provided between the welding surface of the metal block and the optical connection surface of the sub-module body. It is to provide an optical module. This barrier is either a step provided so that the welding surface of the metal block and the optical connection surface of the sub-module body are displaced, or is placed across both sub-modules between these welding surface and abutting surface. Can be achieved by a baffle.

[0007]

When a barrier is provided between the welding surface of the metal block and the optical connection surface of the sub-module body as described above, the slag generated when the welding surface of the metal block is irradiated with a YAG laser to perform welding is lighted. The sub-module can be connected without invading the optical connection surface for transmission by the transmission and without causing transmission loss.

[0008]

1 and 2 show an optical module according to the present invention. In the illustrated embodiment, the optical module is a waveguide type optical circuit. Although shown as component 10A, the invention is equally applicable to other optical circuit components, as will be described later.

The waveguide type optical circuit component 10A includes a waveguide circuit component (submodule) 12 and an input / output fiber component (submodule) 14 joined to both ends of the waveguide circuit component 12 as in the conventional case. 16 and these sub-modules are joined in an aligned state. The waveguide circuit component 12 is composed of a chip-shaped waveguide element 22 adhered to the metal block 18 by a lid 20, and the input / output fiber components 14 and 16 are the metal block 24.
Fiber arrays 28 and 3 which are respectively adhered and fixed to 26
It consists of zero.

The end face of the waveguide circuit component 12 and the end faces of the input / output fiber components 14 and 16 are flat-polished. These components 12, 14 and 16 are arranged so that the end faces polished as described above are butted against each other, and the waveguide element 2
After aligning the cores of No. 2 and the cores of the fiber arrays 28, 30 so as to match each other, as shown in FIG.
Laser beams emitted from a plurality of YAG laser heads 32, 34, 36 and 38 are laterally applied to the welding surfaces of the welding parts 4 and the components 12 and 16 and joined to each other.

The waveguide type optical circuit component 10A includes a welding surface 40 between the metal block 18 of the waveguide circuit component 12 and the metal block 24 of the input fiber component 14 and the waveguide circuit component 1.
A welding surface (welding surface) 42 of the metal block 18 of No. 2 and the metal block 26 of the output fiber component 16 and the waveguide element 22
And barriers 48 and 50 between the optical connection surfaces 44 and 46 of the fiber arrays 28 and 30, respectively.

In the embodiment of FIGS. 1 and 2, these barriers 48, 50 are welded surfaces 40, 42 and optical connection surfaces 44, 46.
And step s provided so that and are displaced in the light transmission direction,
Made of s'. This step difference of about 1 mm is sufficient. In the embodiment shown in FIGS. 1 and 2, this step protrudes from the optical connection surfaces 44A and 46A on the side of the waveguide circuit component 12 and dents the welding surfaces 40A and 42A. Although the optical connection surfaces 44B and 46B are dented and the connection surfaces 40B and 42B are projected, the projection and the dent may be reversed.

Thus, the metal blocks 18 and 24, 2
6 between the welding surfaces 40 and 42 of FIG. 6 and the optical connection surfaces 44 and 46 of the waveguide element 22 and the fiber arrays 28 and 30.
8 and 50, the slag generated when welding the welding surfaces 40 and 42 of the metal blocks 18, 24 and 26 by irradiating the YAG laser to the metal blocks 18, 24 and 26 may enter the optical connecting surfaces 44 and 46 through which light is transmitted. In addition, the waveguide circuit component 12 and the input / output fiber components 14 and 16 can be connected without transmission loss.

If the step size is ideally 1 mm for the waveguide circuit component 12, the input / output fiber component 1
4 and 16 are 1 mm with an error of several micrometers. This step is preferably as small as possible in order to perform accurate end face machining. On the other hand, if the penetration during welding is increased, the strength of the welded portion is increased, but slag is likely to enter, which is not preferable.

In the illustrated embodiment, the external dimensions of the waveguide circuit component 12 are preferably set larger than the external dimensions of the input / output fiber components 14 and 16. The reason for this is that when welding is performed after aligning the cores of these components so that they are aligned with each other, the external dimensions of the waveguide circuit component 12 and the input / output fiber components 14, 16 are the same. A step occurs on the abutting surface to be welded due to the core, and the direction of this step is not known until the centering is performed.Therefore, the welding condition is not constant and the position shift occurs during welding, which reduces the yield. Waveguide circuit component 12
Is set to be larger than the external dimensions of the input / output fiber components 14 and 16, the waveguide circuit component 12 is set to the input / output fiber components 14 and 1 even after the cores of these components are aligned.
Since it projects more than 6, the welding conditions are always almost constant and the yield is improved.

3 and 4 show a waveguide type circuit component 10A according to another embodiment of the present invention.
Has no step between the welding surfaces 40, 42 and the optical connecting surfaces 44, 46, the welding surfaces 40, 42 and the optical connecting surfaces 44, 46 are formed on the same plane, and the barriers 48, 50 are formed on the welding surfaces. Four
1 and 2 except that it consists of baffles 52, 54 arranged between the optical components 0, 42 and the optical connection surfaces 44, 46.
Is exactly the same as the embodiment of The baffles 52, 54 are arranged so as to be engaged with the engaging grooves 18a, 18b and 24a, 26a provided on the surfaces of the metal blocks 18 and 24 and 18 and 26 facing each other.

Also in this embodiment, the slag generated when the welding surfaces 40 and 42 are welded is prevented from reaching the optical connection surfaces 44 and 46 by the baffles 52 and 54, so that they pass through the optical connection surfaces 44 and 46. There is no transmission loss of the generated light.

5 and 6 show an example in which the present invention is applied to a semiconductor laser module 10B instead of a waveguide type circuit component. The semiconductor laser module 10B includes a laser chip component 60, a lens component 62, and an output fiber component 64. The laser chip component 60 is composed of a metal block 66 and a laser chip 68 mounted in the metal block 66. Lens parts 62
Is composed of a metal block 70 and a lens 72 mounted in the metal block 70. Further, the output fiber component 64 is composed of a metal block 74 and an optical fiber 76 which is adhered and fixed in the metal block 74. Between the welding surfaces 78, 80 of these parts 60 and 62 and 62 and 64 and the optical connection surfaces 82 and 84, a barrier 8 is provided.
6, 88 are provided.

In the illustrated embodiment, the barriers 86, 88 are ring-shaped baffles 90, similar to the embodiments of FIGS.
The baffle plates 90 and 92 are provided with engaging grooves 66a and 70a provided on the opposite surfaces of the metal blocks 66 and 70, and engaging grooves 70b provided on the metal blocks 70 and 74, respectively. It is arranged so as to straddle 74a. These parts 60, 62, 64 are
After the core is aligned, the welding surfaces 78 and 80 are welded and fixed by the laser emitted from the YAG laser heads 94, 96 and 98 arranged at equal intervals in the circumferential direction.

In this embodiment, parts 60, 62 and 62
And the slag generated when welding 64 to the baffle plate 90,
Since 92 prevents the optical connection surfaces 82 and 84 from reaching the optical connection surfaces 82, transmission loss of light passing through the optical connection surfaces 82 and 84 does not occur.

[0021]

As described above, according to the present invention, since a barrier is provided between the welding surface of the metal block and the optical connection surface of the sub-module body as described above, the welding surface of the metal block is irradiated with YAG laser. The slag generated at the time of welding does not enter the optical connection surface where light is transmitted, and there is a merit that the sub-module can be connected without transmission loss.

[Brief description of drawings]

FIG. 1 is a perspective view of an embodiment of a waveguide type optical circuit component to which the present invention is applied, before welding the components to each other.

FIG. 2 is a horizontal sectional view of the waveguide type optical circuit component of FIG. 1 in a welded state.

FIG. 3 is a perspective view of another embodiment of the waveguide type optical circuit component to which the present invention is applied before the components are welded to each other.

FIG. 4 is a horizontal sectional view of the waveguide type optical circuit component of FIG. 3 in a welded state.

FIG. 5 is a horizontal cross-sectional view of a semiconductor laser module according to an embodiment of the present invention in a welded state.

6 is a front view of the semiconductor laser module of FIG.

FIG. 7 is a perspective view of a waveguide type optical circuit component according to a conventional technique before welding the components to each other.

FIG. 8 is a perspective view of the waveguide type optical circuit component of FIG. 7 in a welded state.

[Explanation of symbols]

 10A Waveguide type optical circuit component 10B Semiconductor laser module 12 Waveguide circuit component 14 Input fiber component 16 Output fiber component 18 Metal block 20 Lid 22 Waveguide element 24 Metal block 26 Metal block 28 Fiber array 30 Fiber array 32 Laser head 34 Laser Head 36 Laser head 38 Laser head 40 Welding surface 42 Welding surface 44 Optical connection surface 46 Optical connection surface 48 Barrier 50 Barrier S Step S'Step 52 Baffle plate 54 Baffle plate 60 Laser chip component 62 Lens component 64 Output fiber component 66 Metal block 68 Laser Chip 70 Metal Block 72 Lens 74 Metal Block 76 Optical Fiber 78 Welding Surface 80 Welding Surface 82 Optical Connection Surface 84 Optical Connection Surface 86 Barrier 88 Barrier 90 Baffle Plate 92 Baffle Plate

Claims (1)

[Claims] 1. A plurality of sub-modules comprising a metal block and a sub-module body fixedly adhered to the inside of the metal block. Adjacent sub-modules are adhered and fixed to each other by the metal blocks, and the sub-module bodies are mutually opposed. In the optical modules connected together, a barrier is provided between the welding surface of the metal block and the optical connection surface of the sub-module body.