JPH0473841B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to an optical fiber connecting tool for connecting optical fibers to each other or connecting optical fibers to a light source/receiver through a lens body.

Prior Art Optical fiber connectors that make connections through lens bodies have the advantage of allowing the connectors to be used without contacting each other, and that the light-receiving surface of non-fibers can be substantially enlarged. are being considered.

FIG. 2 shows a non-fiber connector already proposed by the applicant in Japanese Patent Application No. 58-188839.
The optical fiber cord 2, one end of which is held in the optical fiber connector 1, has a
Kevlar 3 as reinforcing fiber, optical fiber core wire 4,
and the bare optical fiber 5 are exposed. The optical fiber bare wire 5 and the optical fiber core wire 4 are inserted into an optical fiber sleeve 6, and are fixed to the sleeve 6 with the end surface of the optical fiber bare wire 5 and the end surface of the sleeve 6 flush with each other. The optical fiber core wire crimping pipe 7 is crimped.

The small diameter portion 6a of the sleeve 6 is inserted into a lens sleeve 12 into which a cylindrical gradient index lens 11 is inserted and fixed, and in this state, the sleeves 12 and 6 are connected to a substantially cylindrical guide 13. inserted inside.

The bare optical fiber 5 is inserted into the axial center of the small diameter portion 6a, and the outer diameter of the small diameter portion 6a is approximately equal to the inner diameter of the sleeve 12. Therefore, simply by inserting the small diameter portion 6a into the sleeve 12, the bare optical fiber 5 is arranged coaxially with the lens 11. In order to prevent connection loss between the bare optical fiber 5 and the lens 11, matching oil is applied to the tip end surface of the small diameter portion 6a. Further, in order to smoothly insert this small diameter portion 6a into the sleeve 12, the above-mentioned oil is also applied to the outer peripheral surface of the small diameter portion 6a. A through hole 12a is formed in the wall surface of the sleeve 12 to vent air and oil during this insertion.

A compression coil spring 1 is attached to the large diameter portion 6b of the sleeve 6.
4 is inserted externally, and a substantially cylindrical protection pipe 15 is screwed into the guide 13. Therefore, the spring 14 is compressed by screwing the pipe 15, and the flange portion 6c of the sleeve 6 is compressed by the spring 14.
The sleeve 6 is elastically pressed toward the lens 11 by the repulsive force. Due to this pressing, the end surfaces of the small diameter portion 6a and the bare optical fiber 5 are brought into close contact with the end surface of the lens 11, and further,
The flange portion 12b of the sleeve 12 is in contact with the inward flange portion 13a of the guide 13.

A substantially cylindrical holder 16 is fixed to the inclined end surface 15a of the protection pipe 15 by screwing or undercutting. Also, pipe 15
Kevlar 3 coated with adhesive is guided to the interface between the holder 16 and the holder 16 . For this purpose, Kevlar 3
When the adhesive applied to the optical fiber cord 2 hardens, the tensile force when the optical fiber cord 2 is stretched is transmitted to the pipe 15 and the holder 16 via the Kevlar 3.
Since it is not transmitted to the optical fiber core wire 4, the optical fiber core wire 4 is protected from the tensile force load. Note that a cap nut 17 is inserted into the guide 13.

Therefore, if the gradient index lens 11 has a length that is an odd number multiple of 1/4 pitch of the meandering period of light,
As shown in FIG. 2, by inserting a pair of sleeves 12 into a common guide 18 and screwing them together with a cap nut 17, the optical fibers are optically connected without contacting each other.

In addition, if the gradient index lens 11 has a length that is an integral multiple of 1/2 pitch of the meandering period of the light, the light source or receiver to which the condensing lens is attached can be connected to the optical fiber without contact. can be optically connected. According to the optical fiber connector 1 as described above, the optical fiber which is the first holding member holds the bare optical fiber 5 and the fiber core wire 4 with the end face of the bare optical fiber 5 exposed. sleeve 6
is elastically pressed by a compression coil spring 14.

Therefore, the end face of the bare optical fiber 5 is surely in close contact with the end face of the gradient index lens 11, which is the lens body held in the lens sleeve 12, which is the second holding member, immediately after assembly. . Therefore, the optical fiber connector 1 can transmit optical signals immediately after assembly without waiting for the adhesive to harden, as is the case when the sleeve 6 and sleeve 12 are fixed with epoxy resin, for example.

Problems to be Solved by the Invention However, the pressing force of the spring 14 does not necessarily act only in the axial direction of the sleeve 6, but also has a component in a direction perpendicular to the axis. For this reason, if the sleeve 18 is a split sleeve with a split in the axial direction and the tightening force of the cap nut 17 is not so large, the sleeve 18 will
The sleeves 12 and 18 are expanded in the radial direction, causing an angular misalignment between the sleeves 12 and 18. Therefore, with such an optical fiber connector 1, highly efficient connections cannot necessarily be made.

SUMMARY OF THE INVENTION In view of these problems, it is an object of the present invention to provide an optical fiber connector that can transmit optical signals immediately after assembly and can perform highly efficient connections.

Means for Solving the Problems In the optical fiber connector according to the present invention, a first holding member holding an optical fiber and a second holding member holding a lens body are connected to each other by soldering. Fixed.

Operation By soldering the first and second holding members, these holding members are immediately fixed to each other, and there is no need to apply an external force to these holding members for fixing.

Embodiment An embodiment of the present invention will be described below with reference to FIG.

As shown in FIG. 1, in the optical fiber connector 21 of this embodiment, the compression coil spring 14 is not used, but instead the flange portion 6c of the optical fiber sleeve 6 and the flange portion of the lens sleeve 12 are used. 12b is fixed by solder 22, and the protective pipe 15 is long enough to form a gap of 1 to 2 mm between the end surface of the protective pipe 15 and the flange portion 6c. It may have substantially the same configuration as the optical fiber connector 1 shown in FIG.

According to such an optical fiber connector 21, since the protective pipe 15 is long, the bare optical fiber 5 and the optical fiber core wire 4 are more reliably protected, but the end face of the pipe 15 and the flange portion 6c of the sleeve 6 are Since a gap of 1 to 2 mm is formed between them, no external force is applied to the sleeve 6 by screwing the pipe 15 into the guide 13.

Effects of the Invention As described above, the optical fiber connector according to the present invention has the first holding member holding the optical fiber and the second holding member holding the lens body fixed to each other by soldering. I am trying to do this, so
Optical signals can be transmitted immediately after assembly, and there is no need to apply external force for the above-mentioned fixation, so even when the above-mentioned holding member is inserted into a split sleeve, there is no angular misalignment between this split sleeve and the holding member. This allows highly efficient connections to be made.

[Brief explanation of drawings]

FIG. 1 is a schematic side sectional view showing one embodiment of an optical fiber connector according to the present invention, and FIG. 2 is a schematic side sectional view showing an already proposed optical fiber connector. In addition, in the symbols used in the drawings, 2...optical fiber cord, 4...optical fiber core wire, 5...
Optical fiber bare wire, 6...Sleeve for optical fiber,
11... Gradient index lens, 12... Lens sleeve, 21... Optical fiber connector, 22...
It's solder.

Claims (1)

[Claims] 1. A first holding member that holds the optical fiber with one end surface of the optical fiber exposed, and a first holding member that holds a lens body and that is in close contact with the one end surface of the optical fiber. and a second holding member fixed to the first holding member by soldering.