JPH07140361A - Module for optical transmission and lens holder rest used therein - Google Patents

Abstract

PURPOSE:To eliminate deviation in an X-axis direction and rotation by providing the lower part of the lens holder rest with an extension part for laser beam welding and subjecting this part to laser beam welding from a z-axis direction. CONSTITUTION:Six elements; a semiconductor laser element, a ball lens 13, an optical fiber to be optically coupled to the semiconductor laser element by a second lens, a stem 101 holding the semiconductor laser element and the first lens 13 and a thermoelectric cooling element mounted with this stem 101 are included in the module for optical transmission of a package type from one end of which the optical fiber can be taken outside. The surface side, in contact with the stem 101, of the lens holder rest 11 for fixing the lens holder 12 mounted with the ball lens 13 to the stem 101 is provided with the extension part 11a for fixing which extends outward.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical transmission module and a lens holder receiver used therein.

[0002]

2. Description of the Related Art In optical communication, an optical module in which an optical waveguide element such as a light source, a receiver, an optical amplifier and an optical fiber as an information medium are optically coupled is used. In such a module, it is important that the optical waveguide and the optical fiber are efficiently coupled and that the coupling is formed so as not to change with time.

There are various methods conventionally used for coupling the optical waveguide element and the optical fiber. An example thereof is shown in FIG. In the conventional technique as shown in FIG. 4, the output light of the semiconductor laser 105 is made incident on the optical fiber 109 by two-lens coupling. In FIG. 4, a stem 101 includes a semiconductor laser 105, a ball lens holder 102, a holder receiver 103, a thermistor 111, and a photodetector 10.
Fix 6 respectively. Further, 104 is a ball lens which is a first lens, 107 is a light beam axis, 110 is a through hole for passing the laser beam collimated by the first lens 104, and 108 is a second lens for focusing on an optical fiber. It is a lens.

With such a configuration, the entire module is housed in a module. At this time, in the above-described configuration, there are the following methods for aligning the ball lens 104 for converting the semiconductor laser light into a parallel beam on the optical axis 107 and fixing it to the stem 101. Description will be made with reference to FIG.

1. The semiconductor laser device 105 is mounted on the stem 10.
Fixed to 1. 2. The semiconductor laser element 105 is electrically connected to an external electrode (not shown). 3. The laser element 105 emits laser light. 4. Ball lens holder 102 and holder receiver 103
Are integrated and finely moved using a manipulator (not shown). 5. The parallelism of the laser light by the ball lens 104 is measured. 6. Laser welding of holder holder 103 to stem 101 1
12 (other side not shown in FIG. 5, but laser welded as well). 7. Ball lens holder 10 using a manipulator
The laser welding 113 is performed again by adjusting the z-axis direction of 2.

Through the above steps, the semiconductor laser 10
5 and the first lens 104 are optically coupled under the optimum condition and fixed to the stem 101.

[0007]

However, in the above-mentioned conventional example, the lens holder receiver 103 is laser-welded 11
At the time of 2, the lower part of the lens holder receiver 103 is simultaneously laser-welded from both side surfaces in the x-axis direction shown in FIG.
At that time, the welding head is in a completely symmetrical position (across the y-axis)
If not present, the heat shock of the laser welding light is biased, and the lens holder receiver 10 is placed in either of the x-axis directions.
3 has a defect that the lens holder receiver 103 is displaced in the xy plane or is rotated.

[0008]

According to the present invention, a protrusion for laser welding is provided in the lower portion of a lens holder receiver, and laser welding is performed from the z-axis direction to eliminate displacement and rotation in the x-axis direction. It is intended for.

That is, according to the optical transmission module of the present invention, an optical fiber optically coupled to the semiconductor laser element by the semiconductor laser element, the ball lens and the second lens which are the first lens. And a stem for holding the semiconductor laser element and the first lens, and an electronic cooling element on which the stem is mounted.
In a package type optical transmission module capable of taking out the optical fiber from the end to the outside, the lens holder holding the ball lens is fixed to the stem. It is characterized in that it has an overhanging part for fixing.

Further, the lens holder receiver of the present invention for fixing a lens holder holding a ball lens forming a part of an optical module in which an optical waveguide element and an optical fiber as an information medium are optically coupled to a stem. In the above, in the above aspect, there is provided a projecting portion for fixing, which projects outwardly, on the surface side in contact with the stem.

More specifically, it is characterized in that the fixing protrusions are protruded on both sides of the surface contacting the stem. It is characterized by using an iron / chromium alloy as the material.

Further, according to the optical communication network of the present invention, a plurality of terminals are arranged on the optical network, and the optical transmission module is incorporated in the plurality of terminals.

[0013]

Embodiments of the present invention will be described below with reference to FIG. FIG. 1A is a top view of this embodiment, and FIG.
FIG. 4 is a front view of this embodiment. 11 is a holder holder with an overhang 11a, 12 is a ball lens holder, and 13 is a first
A ball lens, which is a lens, 14 is a ray axis, and 15 is a first
It is a through hole for passing the laser light collimated by the lens 13.

Next, a method of fixing the ball lens holder receiver 11 when this embodiment is used will be described with reference to FIGS. 1. Fix the semiconductor laser device 105 to the stem 101. 2. Electrically connect to external electrodes (not shown). 3. Laser light is emitted from the semiconductor laser device 105. 4. The ball lens holder 12 and the holder receiver 11 are integrated into a stem 10 using a manipulator (not shown).
Finely move on 1. 5. The parallelism of the laser beam by the ball lens 13 is measured. 6, the holder receiver 11 is attached to the stem 101 by the laser welding head 18 which is set in the z-axis direction.
6 (see FIG. 3). 7. The z-axis direction of the ball lens holder 12 is finely adjusted using a manipulator (not shown), and laser welding 17 is performed again.
Do.

As described above, the lens holder receiver 11 is provided with the projecting portion 11a, and the projecting portion 11a is fixed by laser welding in the z-axis direction. It is now possible to prevent rotation in the xy plane. Also, the laser power during welding can be reduced as compared with the case of welding from the lateral side as in the conventional example.

In the above embodiment, the overhanging portion 11 for fixing is used.
Although a is projected on both sides (with respect to the x-axis direction) on the side in contact with the stem 101, the invention is not limited to this. If you have.

[0017]

The effects obtained by the present invention having the structure described above are as follows. (1) The position of the welding head does not need to be strictly symmetrical. (2) The alignment time of the welding head is shortened. (3) A tool for precise position adjustment is unnecessary. As a result, workability is improved, welding yield is improved, and assembly accuracy is improved.

[Brief description of drawings]

FIG. 1 is a diagram in which the present invention is implemented, (a) is a top view, and (b) is a side view.

FIG. 2 is a side view when the entire stems are combined.

FIG. 3 is a perspective view when the present invention is applied to a stem.

FIG. 4 is a side view showing a conventional example.

FIG. 5 is a perspective view showing a conventional example.

[Explanation of symbols]

 11: Lens holder receiver with overhang 11a: Overhang 12: First lens holder 13: Ball lens that is the first lens 14: Ray axis 15: Through hole 16: Laser welded portion of holder receiver 17: Lens holder and holder Weld part of the receiver. 18: Welding head 101: Stem 105: Semiconductor laser 106: Photodetector 108: Second lens 109: Optical fiber 111: Thermistor

Claims (7)

[Claims] 1. A semiconductor laser device, an optical fiber optically coupled to the semiconductor laser device by a ball lens, which is a first lens, and a second lens, and the semiconductor laser device and the first lens. The ball lens is held in a package type optical transmission module which includes the above six elements of a stem and an electronic cooling element on which the stem is mounted and which can take out the optical fiber from one end to the outside. An optical transmission module having a lens holder receiver, characterized in that an outwardly projecting fixing protrusion is provided on the surface of the lens holder receiver that fixes the lens holder to the stem in contact with the stem. . 2. The projecting portion for fixing is projecting on both sides of a surface side which comes into contact with the stem.
The described module for optical transmission. 3. The lens holder-iron as a material of the receiving member
A module for optical transmission according to claim 1, wherein a chromium alloy is used. 4. A lens holder receiver for fixing to a stem a lens holder holding a ball lens forming a part of an optical module in which an optical waveguide element and an optical fiber as an information medium are optically coupled. A lens holder-receptor characterized in that it has an outwardly projecting fixing protrusion on the surface that comes into contact with the lens holder. 5. The projecting portion for fixing is projecting on both sides of the surface side in contact with the stem.
The described lens holder-receiver. 6. The lens holder-receiver according to claim 4, wherein an iron / chromium alloy is used as a material. 7. An optical communication network in which a plurality of terminals are arranged on an optical network, and the optical transmission module according to claim 1 is incorporated in the plurality of terminals.