JPS6229942Y2 - - Google Patents

Description

[Detailed description of the invention] This invention is designed to be used as a standard prototype when measuring the transmission characteristics of optical fibers for communications.
Relating to standard fiber optic devices.

The transmission characteristics of optical fibers are measured by individual measuring instruments, but if there are variations in the individual measuring instruments themselves, it becomes impossible to compare the data obtained with other measuring instruments. Therefore, it is necessary to eliminate variations between individual measuring instruments. As described above, there is a need for a standard optical fiber device that serves as a standard, which is used for calibration between various measuring instruments and for calibrating measuring instruments when a new measuring instrument is developed.

The purpose of this invention is to provide a standard optical fiber device that does not change over time and can withstand use as a standard prototype.

An embodiment of the present invention will be described below with reference to the drawings. In FIGS. 1 and 2, an optical fiber wire 1 of approximately 2000 to 3000 meters long, which is made by first coating a silica glass fiber with a silicone resin, is wound around a bobbin 2, and this bobbin 2 is made of polyurethane foam or the like. It is wrapped in a cushioning material 3 and sealed in a container 4. The bobbin 2 is made of a material with minimal linear expansion, preferably quartz or carbon steel. Both ends of this optical fiber strand 1 are fusion spliced to an optical fiber core 5 which is covered and protected with a nylon sheath. FIGS. 6 and 6 show this fused portion. This optical fiber core wire 5 is drawn out through the sealing partition 7, and is wound around a plastic bobbin 8 by several meters to several tens of meters. A lid 9 is attached to the container 4 and can be opened and closed with a hinge.
The optical fiber core 5 can be taken out by opening the lid 9.

In this way, most of the length of the optical fiber is made up of the strands 1 having only the primary coating, so that it is not affected by thermal expansion, deterioration, etc. of the coating material. Moreover, since the bobbin 2 is made of a material with a small coefficient of thermal expansion, expansion and contraction of the bobbin 2 due to temperature changes and the like is prevented from causing microbends and changing the transmission characteristics. Moreover, since the core wire 5 with a protective coating is connected to both terminals, it is easy to handle. Since the wire 1 is housed in the sealed container 4, the negative influence of dust can be avoided.

As explained above, according to the present invention, a standard optical fiber device that does not change over time can be realized.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal cross-sectional view of one embodiment of the present invention, and FIG. 2 is a side view as seen from the right side of FIG. 1...Optical fiber wire, 2...Bobbin, 3...
Cushioning material, 4... Container, 5... Optical fiber core, 6
...Fusion part, 7...Sealing partition, 8...Plastic bobbin, 9...Lid.

Claims (1)

[Scope of utility model registration request] A bobbin with a small coefficient of thermal expansion, a predetermined length of optical fiber wire wound around the bobbin and coated only with a primary coating, and the bobbin and the above-mentioned optical fiber wire wound around the bobbin are enclosed. a sealed container,
A standard optical fiber device comprising a protective coated drawing-out optical fiber core wire connected to each terminal of the optical fiber wire and drawn out from the container to the outside.