JP2573247Y2 - Optical semiconductor module - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical semiconductor module in which a micro optical element of an optical module used for an optical communication system, an optical measurement system, or the like is fixed.

[0002]

2. Description of the Related Art First, as an example of an optical module, a semiconductor laser module (hereinafter, referred to as an optical semiconductor module) in an optical semiconductor module will be described.
LD module). The LD module is an assembly in which an optical fiber mounting portion such as a semiconductor laser (hereinafter abbreviated as LD), a focusing lens system, and a receptacle-type housing are integrated. Conventionally, a receptacle type or pigtail type LD module has been known. The receptacle-type LD module has an optical fiber that can be freely attached and detached, and the pigtail-type LD module has an optical fiber attached and fixed. The light emitted from the LD incorporated in the module is efficiently coupled to the optical fiber. It is to let.

[0003] As an example of an LD module, FIG. 4 shows a front view of a half of a receptacle type LD module cut in the axial direction. The receptacle type LD module has a connector coupling sub-assembly 101 and a laser cylinder sub-assembly 102.
Are formed integrally by laser welding 103 with their optical axes aligned. The connector coupling sub-assembly 101
1 is provided with a ferrule insertion hole 112, and a ferrule 115 holding an optical fiber end is inserted into the ferrule insertion hole 112.
When the laser beam emitted from the light emitting chip 122 of the LD 128 is positioned at the end face 113 and passed through the focusing lens 126 such as a GRIN lens or a rod lens, the beam focusing point 114 having the minimum beam diameter and the optical fiber are inserted. Optically coupled.

As a preparatory step, first, as shown in FIG. 5, in a laser cylinder sub-assembly 102, a retainer 123 is provided on a step portion 129 of a cylinder 121 via a spacer 124.
The laser beam emitted from the light emitting chip 122 of the LD 128 attached by screwing is passed through a converging lens 126 whose outer periphery is metallized and fixed to the cylindrical body 121 by solder 145 injected from a small hole 127. the distance L ₁ from the abutment surface 131 to the focal point which is focused Te measured by such as a beam spot size measuring machine. Next, connect the connector subassembly.
The distance L ₂ (see FIG. 6) from the distal end face 132 of the housing 111 of the 101 to the beam focusing point 114 is equal to
A spacer having a different thickness every 0.005 mm and the spacer 124
To find the best spacer.

In a pair of connector coupling subassembly 101 and laser cylinder subassembly 102 such that L ₁ = L ₂ , sliding alignment is performed on contact surface 131 and distal end surface 132, and YAG is positioned at the maximum coupling power. Laser beam spot welding 103 is performed by using a laser or the like, and finally, solder 125 is poured from a small hole 133 on the base end side of the cylinder 121 to completely fix the LD 128 to the cylinder 121 to complete the process.

[0006]

The focusing lens 126 is metallized on the outer periphery of the focusing lens 126 with gold or the like as a metal which has good solderability and is free from rust and corrosion. However, this involves a high-temperature heating step such as a cleaning step or a vacuum evaporation step, which is one of the causes of deteriorating the optical characteristics such as the refractive index of the focusing lens 126. This is a factor in the cost of the module.

[0007]

In view of the above circumstances, the present invention has been made in consideration of the above-mentioned circumstances. Heating is performed at about 100 ° C., which does not cause fluctuation, and is fixed to the cylindrical body 221 by a polymerization reaction by removing water.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to FIGS. The present invention has exactly the same structure as the LD module described as a conventional technique in FIGS. The unmetallized focusing lens 226 at the center of the small outer diameter portion 414 of the cylindrical body 221
0.05mm compared to the diameter of the inside diameter part 411-412
Inner diameter portion 411- having a large band-shaped hollow portion 415-416
A focusing lens 226 is fitted to 412 and the inorganic adhesive 311 is injected from a small hole 413 communicating from the small outer diameter portion 414 to the shaft 417-417 of the cylindrical body 221 and communicating with the band-shaped hollow portion 415-416. Focus the inorganic adhesive 311 while rotating the lens 226
The space between the outer periphery of 226, the inner diameter 411-412 of the small outer diameter portion 414, and the band-shaped hollow portion 415-416 is filled with a jig (not shown) so that the focusing lens 226 does not move in the axial direction. In the state, it air-drys for 2-3 hours. 120
C. × 2 hours of heating (in this case, there is no change in the refractive index of the focusing lens 226), moisture in the inorganic adhesive 311 is removed, and a polymerization reaction occurs, and the focusing lens 226 becomes a cylindrical body 22.
1 is fixed to the inner diameter portion 411-412 and the band-shaped hollow portion 415-416. The inorganic adhesive used here is a silicate or phosphate-based binder that solidifies and cures by a polymerization reaction due to natural drying and moisture removal by low-temperature heating. The surface tension on the material is reduced to facilitate application).

In this state, an external force of 1 to 2 kg is applied to the focusing lens 22.
The shaft is completely fixed even on one end of the shaft.
There is no movement in the direction, and an airtightness of 1 × 10 ⁻⁸ Atm.cc/sec or less can be maintained. Also, -50 ℃ (30 ') ← → + 90 ℃ (3
0 ') Thermal shock test Air tightness is maintained for 300 cycles, and there is no displacement of the focusing lens 226. The shaft-hole fitting adhesion is very effective as described above, but the inorganic adhesive 311 is not applied from the non-fitting portion 418 of the focusing lens 226 protruding forward and backward from the inner diameter portion 411-412 of the small diameter portion 414. Since fine particles of the aggregate component of the reaction may fall, the focusing lens 226
The front and rear ends of the inorganic adhesive 311 three parts of the outer surface of the injection part 312,
If the epoxy resin is applied to 314 and 315 and solidified, the falling of the fine particles can be completely prevented.

[0010]

As is apparent from the above description, according to the present invention, a bar-shaped focusing lens which has not been metallized can be made strong and airtight by an inorganic adhesive by a relatively low temperature treatment and withstands external force. It is possible to provide an optical semiconductor module which can be fixed to withstand thermal shock, can use an inexpensive rod-shaped focusing lens which does not require metallization, and can provide an economical effect.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional front view of a half of an optical semiconductor module according to an embodiment of the present invention.

FIG. 2 is a front view of a half of a cylindrical body 221 which is a component of the optical semiconductor module according to the embodiment of the present invention, which is longitudinally sectioned.

FIG. 3 is a front view of a half section of a cylindrical lens 221 which is a component of an optical semiconductor module according to an embodiment of the present invention, in which a focusing lens 226 not metallized is fixed with an inorganic adhesive 311;

FIG. 4 is a front view of a half of a conventional optical semiconductor module in a longitudinal section.

FIG. 5 is a front view in which a half of a cylindrical sub-assembly 102 of a conventional optical semiconductor module is longitudinally sectioned.

FIG. 6 is a front view of a half of a connector coupling sub-assembly 101 of a conventional optical semiconductor module in a longitudinal section.

[Description of Signs] 101: Connector coupling sub assembly 102, 202: Cylindrical sub assembly 128: Semiconductor laser 126, 226: Focusing lens 311: Inorganic adhesive 312, 314, 315: Epoxy adhesive 221: Cylindrical body 414: Small diameter portion 411 , 412… Inner diameter part 415, 416… Strip-shaped hollow part 413… Small hole 125, 145… Solder

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-61-138904 (JP, A) JP-A-62-187309 (JP, A) JP-A-62-212609 (JP, A) JP-A 61-138609 162011 (JP, A) Fully open sho 61-85812 (JP, U) Fully open sho 63-57605 (JP, U) Fully open sho 62-96607 (JP, U) (58) Fields investigated (Int. ⁶ , DB name) G02B 6/42 G02B 6/32 G02B 6/36 G02B 7/02 H01S 3/18

Claims (2)

(57) [Scope of request for utility model registration] 1. An optical semiconductor module in which a converging lens is fitted to a small outer diameter portion of a cylindrical body having an optical element joined to one end, and a center of an inner diameter portion of the small outer diameter portion to which the converging lens is fitted. Engraving a band-shaped hollow part in the part, drilling a small hole communicating with the band-shaped hollow part and the outside in the small outer diameter part, and setting a curable inorganic adhesive by polymerization reaction from the small hole in the band-shaped hollow part An optical semiconductor module, wherein a focusing lens is fixed to a cylindrical body by filling. 2. The optical semiconductor module according to claim 1, wherein an epoxy resin is applied to an outer peripheral portion of the converging lens projecting from the inner diameter portion and an outer surface of the inorganic adhesive filled in the small hole.