JPS63178203A - Terminal structure for optical connector ferrule - Google Patents

Abstract

PURPOSE:To easily and exactly execute the control of the optical connector ferrule length by fixing a pipe consisting of glass and ceramics, etc., into which an optical fiber has been inserted, into a metallic pipe in a state that its outer end has been extended from the metallic pipe, and cutting the end face of the pipe. CONSTITUTION:An optical fiber cable 2 from which an optical fiber 1 has been extended partially is fixed into a metallic pipe 3 by an adhesive agent, and in a pipe 4 consisting of glass or ceramics, etc., a small diameter hole 5 through which the pipe 4 is inserted is pierced and an extended part of the optical fiber 1 is inserted. The pipe 4 is fixed and fitted into the metallic pipe 3 in a state that its outer end (right end) has been projected from the metallic pipe 3. Subsequently, in a state that the pipe 4 has been projected from the metallic pipe 3, the pipe 4 is cut. In such a way, the length of an optical connector ferrule 6 is determined by cutting of the pipe 4, therefore, the length of the ferrule can be very easily and exactly controlled.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a terminal structure of an optical connector ferrule for coupling optical fibers.

[Conventional technology]

An optical connector consists of an optical connector ferrule (hereinafter referred to as ferrule) that holds and fixes an optical fiber in a predetermined position with high precision, and an alignment section that holds the ferrule against each other.

The conventional ferrule terminal structure has a metal part on the outer periphery,
Many had a pipe made of glass or ceramic placed inside. In this case, the outer peripheral metal part and the inner pipe were configured to be on the same plane. Further, in the case of a single pipe made of metal or ceramic having a small diameter hole slightly larger than the optical fiber, the end of the ferrule was formed by finishing the end surface smoothly.

[Problem that the invention seeks to solve]

The terminal structure of the conventional optical connector ferrule described above requires that the outer metal part and the inner glass or ceramic pipe be on the same plane, but when assembling the optical connector, the optical fiber is After the ferrule was inserted and fixed, the end face of the ferrule was polished to form the same flat surface as described above.

However, since the amount of adhesive that adheres to the ferrule end face when fixing the fiber to the ferrule is not constant, when controlling the ferrule length by polishing the ferrule end face,
It was necessary to manage the dimensions of each terminal, which was difficult and time-consuming. In addition, when polishing the end face of a ferrule, it is difficult to control the polishing because it is necessary to polish three different materials: metal, ceramic, glass, and fiber. There was a drawback that it was difficult to obtain a fiber with a good end face shape.

In addition, since the surface of the ferrule end face to be polished is relatively wide, polishing takes time even when using a ferrule made of a single material, and the proportion of coarse particles is high, resulting in scratches on the fiber end face. It's easy. the fiber end face,
If you try to form them on the same plane by cutting, if the inside is ceramic or glass and the outside is metal,
Alternatively, even if the ferrules are made of the same material, there is a problem in that the diameter of the end face of the ferrule is large, so cutting the ferrule takes time, and the blade used for cutting wears out, resulting in poor blade durability.

An object of the present invention is to provide an optical connector ferrule terminal structure that solves the above-mentioned problems by improving the terminal of the optical connector ferrule.

[Means for solving problems]

The terminal structure of the optical connector ferrule of the present invention has a small diameter hole in the center through which the optical fiber is inserted, and consists of a glass or ceramic pipe and a metal tube coaxially fitted around the outer circumference of the pipe. The optical connector ferrule is characterized in that the outer end of the pipe protrudes slightly from the end surface of the metal tube.

〔Example〕

Hereinafter, one embodiment of the present invention will be described based on the drawings.

FIG. 1 is a longitudinal sectional side view of the terminal of an optical connector ferrule showing one embodiment of the present invention. The optical fiber cable 2, which is partially extended from the optical fiber 1, is attached to a metal tube 3 with adhesive.
It is fixed inside. The pipe 4 made of glass, ceramic, or the like has a small diameter hole 5 through which the pipe 4 is inserted, into which the extending portion of the optical fiber 1 is inserted. The pipe 4 is tightly fitted into the metal tube 3 with its outer end (the right end in FIG. 1) protruding from the metal tube 3. In this way, the optical fiber cable 2 having the optical fiber 1, the metal tube 3, and the pipe 4 constitute the optical connector ferrule 6.

Figure 2 shows the terminal structure of an optical connector ferrule.
A device for cutting the pipe 4 using a grindstone so that the pipe 4 protrudes beyond the metal tube 3 is shown. The metal tube 3 of the optical connector ferrule 6 is fixed to a notch 8 of a jig 7. By bringing the pipe 4 into contact with the grinding wheel 11 rotating in the direction of the arrow around the shaft 9 and moving the jig 7 in the direction of the arrow, the pipe 4 is attached to the optical connector with the pipe 4 slightly protruding from the metal tube 3. The ferrule 6 is cut in a direction perpendicular to the ferrule 6.

In this way, the end face of the optical connector ferrule can be cut within a short period of time by simply cutting the pipe 4 made of glass or ceramic with it protruding from the metal tube 3. Even in the final polishing of the end face of the optical connector ferrule, it is possible to polish only the protruding pipe 4, reducing the polishing area, and polishing materials with similar physical properties such as glass ceramics, so it can be polished in a short time. It is possible to obtain an optical connector ferrule end face with very good surface accuracy.

In addition, by cutting the pipe 4 with a grinding wheel, it is possible to omit the rough polishing and grinding work that is normally performed in the formation of optical connector ferrules, shortening the work time and reducing wear on the grinding wheel. Ru.

Since the length of the optical connector ferrule 6 is determined by cutting the pipe 4, the length of the ferrule can be controlled extremely easily.
and accurate. For this reason, the variation in ferrule length and the pressing force when connecting ferrules was previously adjusted using springs inside the optical connector, but now it is possible to significantly reduce the play in the springs, etc. compared to conventional optical connectors. The mechanical parts of the machine are downsized and simplified.

〔Effect of the invention〕

As explained above, according to the present invention, a pipe made of glass, ceramic, etc. into which an optical fiber is inserted is fixed inside a metal tube with its outer end extending beyond the metal tube, and the end face of the pipe is cut. By doing so, the end face of the optical connector ferrule can be formed in a short time with good surface accuracy, and the length of the optical connector ferrule can be easily and accurately controlled.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional side view of the terminal structure of an optical connector ferrule showing an embodiment of the present invention, and FIG. 2 is a perspective view showing a pipe cutting device for the optical connector ferrule. 1... Optical fiber, 2... Optical fiber cable, 3... Metal tube, 4... Pipe, 5...
...Small diameter hole, 6...Optical connector ferrule, 11...
・Grinding whetstone. Applicant: NEC Corporation Representative

Claims (1)

[Claims] 1. An optical connector having a small-diameter hole in the center through which an optical fiber is inserted, a pipe made of glass or ceramic, and a metal tube tightly fitted coaxially around the outer circumference of the pipe. 1. A terminal structure of an optical connector ferrule, characterized in that, in the ferrule, an outer end of the pipe projects slightly beyond an end surface of the metal tube. 2. The terminal structure of an optical connector ferrule according to claim 1, wherein the end face of the optical connector ferrule is finished by cutting the pipe at a suitable position with a grinding wheel from a direction perpendicular to the ferrule. .