JPS5911881B2 - Optical fiber manufacturing method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an optical fiber manufacturing method, particularly a continuous and integrated manufacturing method for fiber, and relates to a plastic clad fiber using glass as the core and +15 chip having a lower refractive index than the core as the cladding. be.

Conventionally, plastic clad fibers have been produced by drawing a glass rod as a core using some kind of heat source, and applying a drawing process and tandem or batch processing to coat the fiber with a plug-0 stick clad to form a fiber.

However, in the above-mentioned method, the core material is supplied by a glass rod, so that only a finite fiber length can be manufactured, which is limited by the glass rod and the size of the wire to be drawn. Therefore, productivity 25 has been reduced, and this has been one of the factors preventing the supply of cheaper optical fibers. The present invention focuses on the above points, and in order to produce a plastic clad fiber, the core glass rod is made, its diameter 30 is reduced to a size that can be drawn, and the core glass rod is continuously manufactured. The present invention provides a manufacturing method characterized by continuously performing wire drawing and coating with a plastic cladding.

Hereinafter, the present invention will be explained with reference to the drawings.

The drawings show specific embodiments of the present invention, in which quartz is used as the glass. When using quartz as the plastic core, silicone resin or fluorine-based resin is preferable from the viewpoint of refractive index. Reference numeral 1 denotes a burner for producing quartz by flame hydrolysis, to which H2, 02, and 02 as fuel are supplied with SiCl4, SiH4, etc. as a carrier gas.

Moreover, the burner 1 is designed to rotate in order to uniformly grow the SiO obtained as 3. 2 is a device for shaping the outer diameter of the resulting SiO2 X-shaped body so that it has a uniform diameter, and is moved as the burner moves.

3 is the SiO2 glass with a nearly uniform diameter obtained above.
It is a shape body.

4 is a sintering furnace for vitrifying the glass-shaped body 3, and is set at a certain optimum temperature depending on the growth rate, diameter, etc. of the glass-shaped body 3;

5 is a furnace for drawing down the quartz glass rod thus obtained to a diameter suitable for wire drawing.

6 is a tension device for performing the withdrawal, and
This is a device for feeding quartz rods 7 to a drawing furnace 8.

9 is a fiber corresponding to the drawn core.

Reference numeral 10 denotes a coating section for coating the core with a plastic cladding, which is baked in a furnace 11 and wound onto a reel 12.

Through the above series of steps, a plastic-clad optical fiber having quartz as the core and plastic as the cladding is obtained. As an example of an optical fiber prototyped by the method of the present invention, a core diameter of 150 μm, a cladding layer of 100 μm,
A fiber with a core length of 10 mm and a core length of 10 mm was obtained.

(However, if manufacturing continues, in principle, infinite lengths can be manufactured.) The transmission loss is 3 to 5 dB/&! It was confirmed that the product could be manufactured stably.

In the above embodiment, a method using flame hydrolysis using an oxyhydrogen flame burner was described in the case of producing glass or glass sume, but the present invention provides a method for producing glass or glass sume by In addition to these oxyhydrogen flame burners, it is also possible to use a device that does not rely on flame hydrolysis, for example, using a plasma heat source, resistance heating, or the like as a heat source.

As for the components of the deposited glass, silica-based glass is desirable because it is easy to obtain a fiber with low loss, but glass containing additives such as GeO2 and P2O5 may also be used. Further, it may be a glass having a refractive index distribution. Alternatively, it may be a glass in which a portion with a low refractive index (a part of the cladding) is formed in advance on the deposition surface. In addition, in the example, an example was described in which a glass rod or a plastic clad fiber is made from glass in one step, but for example, a glass rod is made continuously, and this is coated with plastic while being yarn-proofed in a separate step. Good too.

That is, the process of continuously producing glass rods and the process of producing plastic clad fibers from glass rods may be separated. As mentioned above, since the present invention carries out an integrated process from glass refining to fiber production, (a) it can be made into a long fiber, improving productivity, (b) it can provide a low-cost fiber, and c) it can provide a low-loss fiber. It has the advantage of being able to supply

[Brief explanation of drawings]

The drawing shows an embodiment of the method for manufacturing an optical fiber according to the present invention. 1... Burner, 2... Molding device, 3.
...Glass X-shaped body, 4...Sintering furnace,
5... Drawing furnace, 6... Tension device,
7...Glass rod, 8...Wire drawing furnace, 9.
... Fiber core, 10 ... Application part, 1
1... Baking furnace, 12... Reel.

Claims (1)

[Claims] 1. A glass body or glass glass is deposited at one end,
The deposited glass or glass cylinder is heated at a location away from the deposition surface to reduce the diameter or sinter and reduce the diameter, and further heated at a location away from the diameter reduction section. 1. A method for manufacturing an optical fiber, which comprises drawing a fiber core to form a fiber core, and coating the fiber core with plastic in the same subsequent step. 2. The method for manufacturing an optical fiber according to claim 1, characterized in that a glass or glass cylinder obtained by rotating a glass or glass synthesis device is used.