JPS6036565B2 - Positioning jig for permanent optical fiber connection - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a pick-up tool that can position two optical fibers with high coaxiality when permanently connecting the ends of two optical fibers by fusing them together.

When using optical fiber as a long-distance transmission line, current technology can only manufacture optical fibers of limited length.
A method is adopted in which multiple optical fibers are connected.

There are two ways to connect optical fibers: one is a connector that can be separated at will even after connection, and the other is a permanent connection (splicing) that cannot be separated after connection.
It can be classified into two methods: In general, connectors have reflection loss at the end of the optical fiber, so
It is known that the connection loss is greater than that due to permanent connection, and this is used appropriately depending on the usage conditions. By the way, when permanently connecting optical fibers, it is important to keep in mind that the two optical fibers cannot be separated after they are connected, so the two optical fibers must be connected with extremely high coaxiality (0 degrees). position,
It is necessary to prevent an increase in connection loss by reducing the axial deviation and angular deviation of the core portion.

Therefore, in the past, the two optical fibers 2 and 3 were coaxially positioned using a positioning jig 1 as shown in FIGS. 1 to 3, for example. This is an application of the V block, and Fig. 1 shows the upper surface of this positioning sling tool 1 and the second
The figure shows the external appearance with the optical fibers 2 and 3 positioned, and FIG. 3 shows a cross section taken along the line mm in FIG. 1. This positioning jig 1 has two planes 4.5 that intersect with each other.
A first block 6 is formed in which one optical fiber 2 is routed, and planes 4 and 5 that are the same as the two planes of this first block 6 are formed and the other optical fiber 3 is The main part consists of a second block 7 where the teacher is taught, and these first block 6 and second block 7 are separated by a certain distance, and the two optical fibers 2 and 3 are fused here by arc discharge etc. A working groove 8 for connection is formed. Further, on one plane 4 of the first block 6 and the second flock 7, there is provided a vacuum drawing device for positioning the two optical fibers 2 and 3 coaxially on the two planes 4 and 5, respectively. A suction rod 9 is cut along the intersection line 1 of the two planes 4 and 5, and a suction pipe 11 connected to a vacuum pump (not shown) is conveyed through the suction groove 9 in the first block 6 and the second block. It protrudes from block 7. Since the second planes 4 and 5 are smooth mirror surfaces with excellent flatness, each optical fiber 2 and 3 is connected to the first plane. The optical fibers 2 and 3 are automatically positioned coaxially by applying a vacuum to the rack 6 and the second block 7 and drawing a vacuum. Note that the optical fibers 2 and 3 are connected to the first block 6.
As a means for positioning and fixing to the second block 7, in addition to the above-mentioned vacuum method, for example, Japanese Patent Application Laid-Open No.
As shown in Japanese Patent No. 17039, a method using a presser plate is also known. Nowadays, it is thought that it will be relatively easy to obtain optical fibers with low loss of less than 1 dB/millimeter in the near future, and there is an urgent need to suppress the connection loss of optical fibers as much as possible. Various studies have been conducted on this topic.

However, since the diameter of the core portion of a typical optical fiber is only about several tens of micrometers, the difficulty of coaxial positioning can be easily understood. For example, in the conventional positioning tool 1 described above, two optical fibers 2 and 3
Before placing the two planes 4 and 5 on the first block 6 and second block 7, respectively, observe the two planes 4 and 5 with a microscope. However, the size of the foreign object is 10
If it is less than micrometers, it becomes extremely difficult to remove it, and the optical fibers 2 and 3 and the two flat surfaces 4 and 5
There was a prisoner who was caught between the neck and the neck. It has been found that in such a case, the degree of coaxiality between the two optical fibers 2 and 3 is significantly reduced, and a solution to this problem has not yet been found. From this point of view, the present invention aims to provide a pick-up tool that can position an optical fiber with high coaxiality without being affected by the presence of foreign matter.
This is intended to reduce the connection loss of the optical fiber. The configuration of the positioning device for permanent connection of optical fibers of the present invention that achieves this object is such that two planes intersect with each other are formed, and a first block on which one optical fiber is placed, and the second block. a second block in which the same plane is formed as the two optical fibers, and on which the other optical fiber permanently connected to the one optical fiber is stacked, are arranged at a certain distance apart, and the two optical fibers are An optical fiber fixing means is provided which is attached to the two planes of the first block and the second block to coaxially position them, and is further attached to each of the two planes and connects these two planes and the two planes. A countless number of micro holes are formed on each of the two planes to accommodate microscopic foreign objects that are present at the contact portions of the book with the optical fibers by the longitudinal squeezing action of these two optical fibers. It is something.

Hereinafter, an embodiment of the positioning jig for permanent connection of optical fibers according to the present invention will be described in detail with reference to FIG. 4. The appearance and general structure of this embodiment are shown in FIGS. Since it can be the same as the conventional one, only the parts that are different from this conventional one will be explained here, and for other parts that are the same as the conventional one, the same as the conventional one is shown in Figures 1 to 3. It is only indicated by the same symbol as .

Note that FIG. 4 corresponds to a sectional view of this embodiment similar to FIG. 3. In the present invention, 10 particles that are difficult to remove and adhere to the two flat surfaces 4 and 5 of the first block 6 and the second block, respectively, are used.
It is sufficient to form innumerable micropores on these two planes 4 and 5 that can accommodate foreign matter such as dirt and dust of about micrometers or less, and in this embodiment, innumerable closed cells (microscopic The first block 6 and the second block 7 are entirely composed of porous metal or porous ceramic having pores 13.

Even in this case, each of the two planes 4 and 5 needs to be machined to the highest level of flatness, so that countless microscopic holes are drilled on the mirror surface. In addition, when the optical fiber fixing means is configured by a method using vacuum suction as in this embodiment,
Although it is impossible to construct the first block 6 and the second block 7 entirely from porous metal or porous ceramic made of deep air bubbles, this is because the flow of air to the suction pipe 11 from sources other than the suction pipe 9 is impossible. This occurs and the optical fiber 2
, 3 on the two planes 4 and 5, respectively. However, it is possible to construct the positioning pick 1 by pasting these thin plates on each of the planes 4 and 5, and it is also possible to fix the optical fiber with a holding plate as shown in Japanese Patent Application Laid-Open No. 1703-1983. If such means are constructed, these open-celled ones can be used without any problems, and the suction grooves 9, suction pipes 11, etc. are completely unnecessary. In addition, microscopic holes 4 of about 5 to 10 micrometers may be formed on each of the two planes 4 and 5 which have been mirror-finished by chemical corrosion. As above, the first block 6
By forming closed cells 13 capable of containing foreign matter on each of the two flat surfaces 4 and 5 of the second block 7, the two optical fibers and these two Even if a foreign object is present in the rear part 12 where the optical fibers 2 and 3 come into contact with the two planes 4 and 5, the optical fibers 2 and 3 should be By squeezing several times in the direction parallel to the line 10), foreign matter present in the saddle portion 12 is scraped off into the closed cell 13, and the optical fibers 2, 3 are tightly applied to the entire two planes 4, 5. It becomes possible to make it twill.

Therefore, the two optical fibers 2 and 3 can be positioned with extremely high precision, thereby making it possible to further reduce connection loss between the optical fibers 2 and 3. As described above, according to the positioning jig for permanent connection of optical fibers of the present invention, numerous micro holes are formed on the two planes of the first block and the second block, which the optical fibers contact, respectively, so that the optical fibers can be easily pressed. By the operation, microscopic foreign objects are scraped into these countless microscopic holes, and as a result, the optical fiber can be positioned with extremely high precision, and as a result, it is possible to further reduce the connection loss of the optical fiber.

[Brief explanation of the drawing]

Figure 1 is a plan view of the optical fiber positioning tool for permanent connection of the slave, Figure 2 is its external view, and Figure 3 is m in Figure 1.
FIG. 4 is a sectional view similar to FIG. 3, showing an embodiment of the positioning tool according to the present invention. 1 is a positioning pick, 2 and 3 are optical fibers, 4 and 5 are planes for positioning, 6 is a first block, 7 is a second block,
8 is a working groove for connection; 9 is a suction groove; 11 is a suction tube; 12 is a contact portion between the optical fiber and the two flat surfaces; 13 is a closed cell. Boar 1 Illustration 2 Illustration 3 Sei 4 Illustration

Claims (1)

[Claims] 1. Two planes intersecting each other are formed, and a first block on which one of the optical fibers is placed, and a plane that is the same as the two planes, and a permanent connection with the one optical fiber is formed here. A second block on which the other optical fiber is mounted is arranged at a certain distance, and the two optical fibers are brought into contact with the two planes of the first block and the second block, respectively. An optical fiber fixing means for coaxially positioning the optical fibers is provided, and minute foreign matter adhering to each of the two planes and intervening at the abutting portions of these two planes and the two optical fibers is removed from the two planes. 1. A positioning jig for permanently connecting optical fibers, characterized in that countless microscopic holes are formed on the two planes to accommodate the optical fibers by squeezing the optical fibers in the longitudinal direction.