JP2597011Y2 - Fixing structure of semiconductor laser module unit - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fixing structure of a semiconductor laser module unit for coupling outgoing light of a semiconductor laser to an optical fiber, and more particularly to a DIL (Dual In Line) type and a butterfly type of the semiconductor laser module unit. The present invention relates to a fixing structure of a semiconductor laser module unit fixed to a metal case such as a package.

[0002]

2. Description of the Related Art Generally, there are two types of semiconductor laser modules (hereinafter referred to as LD modules), which are key devices in an optical communication apparatus, in terms of structure.
One type is a type called a coaxial type, and L
D, an optical fiber, a condensing lens, etc. are fixed in a cylindrical member, and the other type is a rectangular case called a DIL package or a butterfly package, etc. in a rectangular case such as an LD, an optical fiber, a lens, etc. This is a type on which system components are mounted.

The latter type is used when a thermo module for controlling the temperature of the LD is built in, but is also used in the case of a non-cooled type module because of easy mounting on a printed circuit board. Often.

When an LD module is placed in a rectangular case such as a DIL package, the LD, lens,
There are a structure in which components such as an optical fiber terminal are arranged, and a structure in which a small module is assembled outside the case and the small module is mounted on the case.

A structure in which components are directly arranged in a case can realize a module with a small number of components and a small size and excellent heat radiation characteristics of the LD, but on the other hand, a component such as an LD, a lens and an optical fiber terminal can be mounted in a narrow case. There was a problem that the optical axis had to be adjusted and fixed with high accuracy, and the manufacturing cost was high.

On the other hand, in a structure in which a small module is mounted on a case, there is no need to adjust and fix the optical axis in a narrow case. It has a characteristic that the system is stable, and can use common components with the coaxial type. Therefore, it is generally adopted more than a structure in which components are directly arranged in a case.

FIG. 3 is a cross-sectional view showing a conventional structure for mounting the above-described small module in a case.

The components such as the LD, lens, and optical fiber terminal are assembled in advance to constitute the optical system unit 11, and the optical fiber terminal side 11a of the optical system unit 11 is thinner than the main body side. The optical fiber cable 12 is connected to the terminal side 11a.

A block 13 is fixed to the lower part of the optical system unit 11 by soldering or the like, and the optical system unit 11 is opened on the metal case 14 by soldering the block 13 to the metal case 14. Is fixed at a position where the optical fiber terminal side 11a protrudes from the hole 14a.

Further, a cover 15 for protecting the optical fiber terminal side 11a of the optical system unit 11 protruding from the metal case 13 is provided on a side surface of the metal case 13, and the cover 15 is provided with the optical fiber cable 12 therein. A hole 15a to be inserted is formed.

[0011]

In the conventional LD module, the optical system unit 11 and the block 13 and the block 13 and the metal case 14 are fixed by soldering, and it is necessary to apply plating to the soldered portion. In addition, there are disadvantages in that the cost of parts is increased and that the heating and cooling work for soldering is troublesome. Further, there is a possibility that an external force applied to the optical system unit 11 via the optical fiber 12 may be generated, and a soldered portion of the optical system unit 11 may be displaced or lose the fixing force due to thermal stress due to a temperature cycle. And the strength may be insufficient.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a fixing structure of a semiconductor laser module unit having sufficient strength so that the LD laser module unit is fixed without soldering and the unit is not shifted due to thermal stress.

[0013]

The fixing structure of the semiconductor laser module unit according to the present invention is provided near the optical fiber side end of the housing of the semiconductor laser module unit.
Along the same axis as the optical axis of this optical fiber.
And a larger diameter than the male thread
Of this plane as the central axis and a plane perpendicular between the body-side
The above-mentioned half, in which a stepped portion having a vertical and cylindrical shape having a predetermined radius is provided, and only a male screw portion of the semiconductor laser module unit protrudes outside on one side plate of the metal case.
A hole with a diameter slightly smaller than the diameter is provided, a fixing nut for screwing into a male screw of the semiconductor laser module unit housing is prepared, and a male screw and a fixing nut of the semiconductor laser module unit housing protruding from the metal case are provided. And fixing the semiconductor laser module unit to the metal case by sandwiching the side plate of the metal case between the flat surface of the step portion of the semiconductor laser module unit and the end face of the fixing nut , and the end face of the fixing nut. Opposite
A hole for inserting an optical fiber is
It is characterized in that that.

Further, it is preferable that the threaded portion between the male screw and the fixing nut of the housing of the semiconductor laser module unit is bonded with an adhesive.

[0015]

Based on the above-described structure, the fixing structure of the semiconductor laser module unit according to the present invention is such that only the male screw portion of the housing of the semiconductor laser module unit provided in the metal case projects outside the hole. The male screw of the housing is arranged so as to protrude from the hole of one side plate of the metal case, and the male screw of the semiconductor laser module unit protruding from the metal case and the fixing nut are screwed together,
The semiconductor laser module unit is fixed to the metal case by sandwiching the side plate of the metal case between the step portion of the semiconductor laser module unit and the fixing nut.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings.

(1) Embodiment of the Invention According to Claim 1 FIG. 1 is a sectional view of an embodiment of the invention according to claim 1.

Parts such as an LD, a lens, and an optical fiber terminal are assembled in advance to form an optical system unit 11. The optical fiber terminal side 11a of the optical system unit 11 is thinner than the main body side. A male screw 11b is engraved on the housing on the terminal side 11a, and an optical fiber cable 12 is connected to the optical fiber terminal side 11a.

A hole 14a for projecting the optical fiber terminal side 11a of the optical system unit 11 out of the case is formed in one side plate of the metal case 14, and the hole 14a is formed in the optical fiber terminal side of the optical system unit 11. By screwing the fixing nut 16 screwed into the male screw from the outside of the case and the male screw 11b with the 11a protruding out of the case, the step portion 11c on the main body side of the optical system unit 11 and the fixing nut 16 are screwed. The optical system unit 11 is fixed to the metal case 14 with the metal case 14 interposed therebetween.

The fixing nut 16 has a hole through which the optical fiber cable 12 is inserted.

Next, the operation of this embodiment will be described.

Optical fiber terminal side 1 of optical system unit 11
A male screw 11b is engraved on 1a, and a hole 14a is formed in the metal case 14 so that only the male screw 11b of the housing on the optical fiber terminal side 11a of the optical system unit 11 projects outside the case. Then, only the male screw 11b is disposed at a position protruding outside the case, and the male screw 11b protruding from the metal case 14 is provided.
b and the fixing nut 16 are screwed together, and the side plate of the metal case 14 is sandwiched between the step portion 11c and the fixing nut 16 to fix the optical system unit 11 to the metal case 14.

(2) Embodiment of the Invention According to Claim 2 FIG. 2 is a sectional view of an embodiment of the invention according to claim 2. The same parts as those described above are denoted by the same reference numerals and description thereof will be omitted.

A feature of the invention according to claim 2 is that, when the male screw 11b and the fixing nut 16 are screwed together, an adhesive is applied to the screwed portion A, and the male screw 1 is formed by the adhesive force of the adhesive.
1b and the fixing nut 16 are prevented from coming off. Also, after the terminals 17 of the LD and the monitor PD are fixed to the terminals 18 in the case by soldering with the wiring printed circuit board 19 and wired, the cover 20 is attached to the metal case 14 by seam welding.

As a result, since the optical system unit 11 and the metal case 14 are mechanically fixed, a force is applied to the optical system unit 11 and the wiring portion inside the metal case 14 to make it difficult, and the reliability is secured. I have. Then, the heat generated by the LD is sufficiently radiated from the optical system unit 11 to the outside through the contact portion with the case 14.

Although the thermal resistance is higher than that of the conventional example, it has been confirmed that there is no problem in reliability even at a high temperature operation of 85 ° C. due to the improvement of the performance of the LD element. It has been found that when the state is about 65 degrees, the heat radiation characteristics never cause a serious problem in reliability.

[0027]

As described above , according to the present invention , a step having a diameter slightly larger than the size of the hole in one side plate of the metal case.
The male screw of the housing of the semiconductor laser module unit having the difference portion is screwed with the fixing nut, and is parallel to the end face of the nut at the step portion of the semiconductor laser module unit.
Strength of the semiconductor laser module unit in a metal case by sandwiching the side plate of the metal case between a surface and the end face
It was configured to be fixed firmly . For this reason, line the soldering
Cormorants necessary without heating, plating the labor and soldered portions of the cooling working can be omitted labor, Ru can reduce the cost. Further, it is possible to prevent the semiconductor laser module unit from coming off or losing the fixing force due to thermal stress . Also, fix the fixing nut
Hole for inserting an optical fiber in the center of the end opposite to the end face
The fixing nut is attached to the laser diode
Just tighten to the external thread of the Joule unit for installation.
It can be easily terminated.

Further, since the male screw and the fixing nut of the housing of the semiconductor laser module unit are bonded with an adhesive, the male screw and the fixing nut are prevented from coming off, and the male screw and the fixing nut are easily opened. Can be prevented.

[Brief description of the drawings]

FIG. 1 is a sectional view of a semiconductor laser module unit according to the present invention.

FIG. 2 is a cross-sectional view of the semiconductor laser module unit of the present invention.

FIG. 3 is a sectional view of a conventional semiconductor laser module unit.

[Explanation of symbols]

 Reference Signs List 11 optical system unit 11a optical fiber terminal side 11b male screw 11c stepped portion 14 metal case 14a hole 16 fixing nut

Claims (2)

(57) [Scope of request for utility model registration] 1. A fixing structure of a semiconductor laser module unit in which a semiconductor laser module unit in which a semiconductor laser and an optical fiber are optically coupled is mounted on a metal case, wherein an end of the housing of the semiconductor laser module unit on the optical fiber side. Near the optical axis of this optical fiber along its outer circumference
The center axis vertical between the externally threaded portion and the main body of a diameter larger than that while engraved male screw around axis in the same direction
A straight plane and a cylindrical shape perpendicular to this plane and of a given radius
And a hole having a diameter slightly smaller than the radius where only the male screw portion of the semiconductor laser module unit protrudes outside is provided on one side plate of the metal case, and the male screw of the housing of the semiconductor laser module unit is screwed. Prepare a fixing nut to be fitted, screw the male screw of the semiconductor laser module unit case projected from the metal case and the fixing nut, and
The semiconductor laser module unit is fixed to the metal case by sandwiching the side plate of the metal case between the flat surface and the end face of the fixing nut , and the fixing nut
A hole for inserting an optical fiber in the center of the end opposite to the end face
Fixing structure of a semiconductor laser module unit, characterized in that There are bored. 2. The fixing structure for a semiconductor laser module unit according to claim 1, wherein a threaded portion of the male screw and the fixing nut of the housing of the semiconductor laser module unit is bonded with an adhesive.