JPS5946615A - Connection part of coated optical fiber - Google Patents

Abstract

PURPOSE:To make various characteristics of non-connection parts and a connection part uniform, by connecting end parts of optical fibers at intervals and forming an intermediate part for the connection part consisting of nonfluid gelling materials or fluid materials on outside circumferences of these end parts and forming a reinforcing resin layer for the connection part on the outside circumference of this intermediate layer. CONSTITUTION:A coat layer 8 for the connection part is applied and hardened on optical fibers 1 which are connected in the exposed state. The coat layer 8 consists of the same curable resin as coat layers 2 or a curable resin similar to that of layers 2. Freely matchable forming molds 9 and 10 are attached to the connection part, and a filler is charged to the space between molds 9 and 10 and the coat layer 8. The filler consists of the same materials as intermediate layers 3 or materials similar to those of layers 3 and has fluidity at the charging time. The filler is charged into the space of molds 9 and 10 through an injector 13 and gels by heating with an electric heater. An intermediate layer 14 for the connection part is formed in this manner and consists of nonfluid gelling materials. Next, a reinforcing resin layer 15 for the connection part is formed on the layer 14.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides an intermediate layer consisting of a Jl-flowable gel-like substance.
The present invention relates to a connection portion of a coated optical fiber having a coating of 111.

1 to 5 have been proposed as coated optical fibers (optical fiber cores) having a layered structure.

To explain these groove formations below, in the coated optical fiber shown in Fig. 1, (1) is a quartz-based optical fiber consisting of a core and a cladding, and (2) is a groove formed on the optical fiber (1). The first coat layer (primary), (3) is the intermediate layer formed on the coat layer (2) and is made of a gel-like material of J1 flow 11, and (4) is the intermediate layer (3) formed on the coat layer (2). )
This is the h+i strong resin 11 for the protective coating formed.

2) IE (21 is made of, for example, a silicone/based thermosetting resin (silicone rubber, silicone resin, modified silicone, etc.).

In this case, the coating layer (2) has not only a primary function but also a buffer function. f, The primary coat layer and the sofa coat rib may be formed as two layers.

When the primary coat layer F1+111 and the sofa coat Ir* above it are formed, they are both made of the same type of resin such as silicone, but except for this, the buffer coat layer 1 is It should be harder than the primary coat layer.

On the other hand, the intermediate layer (3) made of a gel-like substance with a fluid flow rate of 41 is based on the JIS standard (K6aox) (-j2 is 0, A
The scale degree according to STM-DI321 is 80 or higher.

The silicone-based resin composition forming this intermediate layer (3) is heated or exposed to light (usually not exposed to light).
Although it is liquid at 0'l, it crosslinks and becomes a gel (low crosslinking degree) when an appropriate amount of curing energy is applied by heating or light irradiation.

Specifically, the intermediate layer (3) is composed of a polyorganosiloxane containing an unsaturated group, a polyorganosiloxane having a 5i-II group k'N, a catalyst for the monthly reaction, and 1 to 300% of a filler. It is said that

Further, as the reinforcing resin layer (4), thermosetting resins and thermoplastic resins with high mechanical properties are used. Examples of specific soybeans for each of the above include plastic resins.The outer diameter of the optical fiber fil is 125 μm,
The outer diameter of the coating layer (2) is 350 to 400 μm, and the outer diameter of the intermediate layer (
The outer diameter of 3) is 08-09, and the outer diameter of the reinforcing surface fat layer (4) is 0.9-1.2 m+n.

In the coated optical fiber shown in Figure 1, the coating layer (2) prevents surface scratches from occurring on the optical fiber (1) and further prevents residual strain from occurring on the optical fiber (2) due to external force. In addition, the reinforcing resin 9' old 4) is 11IIJ
In addition to these effects, the intermediate layer (3) exhibits various mechanical properties including tensile properties.
) also produces the following effects.

In other words, the middle layer (3) is JIS standard (K 6301)
The hardness according to ASTM-D 1321 is 80 or more, and the hardness is 80 or more according to ASTM-D 1321, so the layer (3) has a liquid or liquid-like appearance. Despite the lack of fluidity, the optical fiber [11] is allowed to move in the radial direction within the l+li strong resin layer (4).

Therefore, even if the reinforcing resin layer (4) expands and contracts due to a change in l function or tension (+11 ton), the stretching force does not act on the original fiber (1), and therefore, this kind of 1ll
This means that no transmission loss occurs due to compression, and furthermore, when the optical fiber (1) is made into a cable, it can move in the cross-sectional direction of the cable, so even if the cable is stretched, the optical fiber (1) will not be distorted, and the so-called The mouth area can be expected to have greater tolerance for elongation.

On the other hand, the intermediate 1+/J+31 is in the form of a non-flowing gel, so it is not extremely soft. Therefore, in normal times, the intermediate 1+/J+31 captures the original fiber Prevent it from moving unnecessarily.

Moreover, this intermediate layer (3) prevents the optical fiber (1) from breaking (even a small stress of V degree causes it to break, and the optical fiber m
e in the radial direction within the same layer (3) (this allows for movement, so n]
It protects the optical fiber (1) by exerting a laxative effect that the coating layer (2) described above does not have, and because it is easily destroyed, the reinforcing resin layer (41) can be easily damaged. The wiping process using chemicals is also simple.

In addition, since the intermediate layer (3) is non-fluid as described above, it will not flow out from the coated end to the outside during connection, and therefore, when connecting coated optical fibers to each other,
It is easy to handle, and of course there is no possibility of high water pressure when laying on the seabed or leakage to the outside during overhead laying.

To explain the coated optical fibers shown in FIGS. 2 and 3, in the case of these coated optical fibers, the layer structure between the coating layer (2) and the reinforcing resin layer (4) is as described in IJ No. 1. It is different from the one shown.

In other words, in FIGS. 2 and 3, not only the intermediate layer (3) but also the hard layer (5
) are also formed.

In this case, the intermediate layer (3) is made of a non-flowable gel-like substance as described above, and is
~ J is 0, ASTM-D I 321 workmanship is 80 or more, but hard 1tri (51 is made of a harder material than the intermediate layer (3), and the layer (5)
The Young's modulus of is IK ri/c1i 2.

Furthermore, there is a clear difference between the one in Figure 2 and the one in Figure 3.

1. In Figure 2, the intermediate layer (3) and the hard layer (5) are made of the same resin composition, and the intermediate layer (3) is gelled and the hard layer (5) is hardened. Therefore, predetermined physical properties are imparted to both layers i31 (51).

In contrast, in Fig. 3, the intermediate layer (3) and the Ijp quality Il'
The intermediate layer (3) is made of the above-mentioned non-flowable gel-like substance, and the hard layer (5) is made of a coat lff1 (2).
It is made of resin used in 1 etc.

To illustrate the specific size of each layer in Figures 2 and 3, the outer diameter of each part except for the middle layer (3) and the hard layer (5) is the same as in Figure 1, and the outer diameter of the middle layer (3) is the same as in Figure 1. Is the outer diameter 800μ?
The thickness of the 71% abrasive layer (5) is 501 tm.

The thinned optical fibers shown in FIGS. 2 and 3 can also provide the same effects as those shown in FIG. 1, and can also be expected to have a plating effect.

As mentioned above, the intermediate layer (3) made of a gel-like substance has low mechanical properties and is easily broken if used alone, so it is directly reinforced to the intermediate layer (3) through extrusion molding means. When trying to form the resin layer (4), a part of the layer (3) comes into contact with the extruder's sobble, etc., and falls off.
This may cause a blockage in the extrusion molding machine, but as mentioned above, the strong hard material h+j t51 is placed in the middle 1m (
When the outer periphery of 31 is filled, the intermediate layer (3) is protected through this, and layer breakage and falling off during the extrusion molding is prevented.

Therefore, during continuous extrusion molding of the reinforcing resin layer (4), there is no possibility that the extrusion molding will be slightly broken, the inside will not be broken, or it will be blocked by fallen residue, and continuous extrusion molding can be performed for a long time, resulting in a high-quality coating. Optical fibers can be manufactured.

For the coated optical fiber 7 shown in FIG. 4, C1t5uJ
4. In this case, a lubricating layer (6) is formed on the outer periphery of the intermediate layer (3) instead of the hard layer (5) in FIGS. 2 and 3 described above. As this viscous layer (6), a liquid or sherry-like material is suitably employed, and a specific example of this is silicone oil.

The size of each layer in Figure 4 is intermediate J+'ff.
The outer diameter of 1 (3) is 800 μm, and the thickness of the mucous membrane layer (6) is 5
The size of the other portions is the same as that of FIG. 1.

The coated optical fiber shown in Fig. 4 has the same effect as the one shown in Fig. 1, and also has a lubricating mucosal layer (6), so it is possible to extrude the reinforcing layer 9 (4). When forming in stages, the outer peripheral surface of the MLL interlayer 3 (and the inside of the extrusion molding machine (
It greatly reduces the friction between the nipple and the nipple and allows the intermediate layer (3) in the extrusion molding machine to run smoothly.

Therefore, when forming the I+LI strong resin layer (4) by the above method, the intermediate layer (3) will not rub against the inside of the extrusion molding machine, and a part of it will not fall and block the inside of the machine, and it will last for a long time. A stable extrusion operation can be maintained.

Of course, this dry layer (6) is membranous and extremely i'! Since it is thin, it does not show fluidity even if it is liquid or sherry-like, and the intermediate IT/1t31 and reinforcing resin layer (4
) exerts a high degree of interfacial tension and self-prevents it from flowing outside.

To explain the coated optical fiber shown in FIG. 5, in the case of this coated optical fiber, the optical fiber t1. An intermediate layer (3) made of the above-mentioned non-flowable gel-like substance is formed on the outer diameter of the chain intermediate layer (3).
) on top of the outer diameter 1.2 nun 1Ili strong tree finger Jrj
(41 is formed.

In the case of this Fig. 5, the intermediate J[rj (31 is the effect of court j (2), that is, the buffer effect q) in addition to the effects described in i1j, and therefore the court I1
．． '1 (2) is omitted.

In addition, in the source fiber shown in Fig. 5, the intermediate layer (
3) and the hli strong resin layer (4), the above-mentioned hard #'
j (51 or old 6) is interposed.

The coated optical fibers shown in FIGS. 1 to 5 described above are equipped with a special intermediate 1ffi [31].
However, these coated optical fibers are usually set to a length (for example, 11 degrees) in consideration of the continuous production capacity of the manufacturing equipment, ease of handling of the product, etc.

-Brim When an optical cable is manufactured by gathering the above-mentioned coated optical fibers by means of a twisting means or the like, a cable having a length of about 70 km is made, for example, for 11σ bottom installation (particularly seamless).

Therefore, when manufacturing the above-mentioned optical cable, the coated optical fibers are connected at a length of 1 to the length of the desired point. At the time of connection, each layer on the outer periphery of the optical fiber is connected at the end of the coated optical fiber, as in the conventional method. If the outer periphery of the connection part is hard coated with paulownia material, which is different from each layer of the coated optical fiber, after connecting the optical fibers, the above-mentioned intermediate Ji'
The effects of i Ic are reduced at the connection f.

The present invention aims to provide a connection section for coated optical fibers that does not cause such problems, and the structure thereof will be explained below with reference to the illustrated embodiments.

FIGS. 6(1) to (V) show connection 1 of the coated optical fiber described in FIG. ! (7) A and (71) 3 in the figure are coated optical fibers, respectively.

! s 6 In Figure (1), two wave 41 optical fibers (7
)A and (7)B, the optical fiber tl+ +1) is exposed by means of cutting the skin and trimmed to a predetermined length; in this case, the coating layer t21 t
The remaining length of 2+ is intermediate layer +31 +31, reinforcing resin layer +4
1 (It is larger than that of 41.

The optical fibers exposed in the above (11fil have their ends abutted against each other and are fused by heating means such as discharge heating or laser heating) are spliced to form the state shown in FIG. 6 (It)066 In Figure (Il), a connecting portion cable (18) is applied onto the optical fiber (1) tl) which is connected in an exposed state by a sprue means or an application means using an applicator. , the same layer (8) is cured by heat or light.

This coating layer (8) for the connection part is
It is made of the same or similar material as +21, specifically, it is made of a silicone-based curable resin.

Further, both ends of the connecting part coat (8) are overlapped on the outer periphery of the end of each coat layer +21 for strength reasons, and these three are integrated.

In addition, the JIS standard (K630
When the hardness according to 1) is 40, the coating layer for the connection part (
The hardness of the layer (8) is also set to be the same, and the outer diameter of the layer (8) (excluding both ends) is the coat layer +21 (2
350-400μ to almost match +? It is set to about n.

After that, as shown in Fig. 6 (1v), both the destination optical fiber +
A pair of molding molds +910o) that can be freely matched are installed over the mutually opposing ends of the molding molds +91H1 and the outer periphery of the connection portion coating layer (8). A predetermined filler is injected into the container.

This filler is made of paulownia material (silicone type) which is the same as or similar to the intermediate layer (3) described in No. 11, and has fluidity at the time of injection.

One side (9) of the above mold +91 QO) has an injection hole 0D.
and an exhaust hole Q21, and the filling material is injected into the mold t91 (101) through the injector 03 attached to the injection hole Gll, and the filling material is injected into the mold t91 (101).
It is gelled by heating from an electric heater (not shown) buried or externally mounted.

The thing formed in this way is shown in Fig. 6 (intermediate
Q Il4), and the intermediate layer - for the connection part is the intermediate layer +3
1 Same as +31 or both layers +31 +31
It is a non-flowing gel-like substance similar to

In addition, the intermediate layer O for this connection part is intermediate 1v4i +31
Like +31, it is sticky, so these champion (3) (3) circles are glued together.

Of course, the outer diameter of the intermediate layer for the connection part is 1mm (
It almost matches the outer diameter of 31(3), specifically 08
~0.9 am.

Incidentally, when forming the joint layer for the connecting portion through the mold +91 (10), a mold release agent is applied to the inner side of the mold as necessary.

In FIG. 6(V), after forming the intermediate layer for the connecting portion, the mold +9) (10) is removed, and the h1j strong resinous disease 051 for the connecting portion is formed on the same layer U.

This Nli strong resin layer α5) for the connection part is formed through a normal injection molding step, etc. Both ends of J (151) are bent over the beaded portion of the reinforcing resin layer (4) (4) for strength considerations.

The reinforcing resin layer 051 for the connection part is a reinforcing resin layer (41+41 is thermoplastic, a thermoplastic one is adopted to match this), and an i+li strong resin layer (41 (same as 4+ is thermosetting) Thermosetting is also used for layer a9.

Of course, the lunar quality of the above layer α9 is the reinforcing resin layer (4+ +41
The outer diameter of the same layer η05) should be approximated to the outer diameter of these reinforcing resin layers (4) (4) (approximately 1.2 mm).

Figures 6 (1) to (V) show the connection method for the coated optical fiber in Figure 1 and its connection part ((4 configuration is shown as an example, but the method shown in Figure 7 can be used to connect 611J). Equivalent connections can be constructed.

In Figure 7, in Figure 6 (IV),
) to (4) dimensions have been completed, and therefore, in this state, only the connecting portion coating layer is formed in dimensions (8).

In FIG. 7 (IV), the tube α5)' which should become one reinforcing resin layer for the connection part has both tip optical fibers (7)A,
(7) It is applied in advance between the ends of B.

This tube 05)' is made of the same or similar material as the reinforcing resin 9+41 +41, such as thermoplastic resin or thermosetting resin, and is 1iiJ to which the optical fiber Ht+l is fusion-spliced. (7) A, (7
) B, and after the coating layer (8) for the connection part is formed, the tube (15)' is coated with the ends of both plates as shown in Fig. 7 (1v). Optical fiber +71A, (71T3 ends).

In addition, Tube Q! If the tube (15+
' can be set as described above even after connecting the optical fiber filF1.1.

1, tube 05 set by any of the above methods
1' is bonded at both ends to each end of the reinforcing resin layer i41 (41), and if there is a split portion, the round portion is also sealed and bonded.

The tube (151') has an injection hole and a JJI hole (
J'/J, and in FIG.
The same filling material as in step 1) is poured into the sh', and the filling material is heated from the tube (151' by means of external heating means) to form a non-flowable gel-like substance as shown in Figure 7 (V). becomes.

Reinforcement resin for connection part 1 yen 05
) and filling. is specified in 11J (the intermediate position for the connection part of θ2).

The size of the two layers 151 thus formed is the same as above.

The connecting portions of the coated optical fibers shown in FIGS. 2 to 5 are shown in FIGS. 8 to 11.

1. In FIG. 8, which shows the connection part of the coated optical fiber described in FIG. , a hard layer u81 for the connection portion is formed.

The connection parts shown in Fig. 8 are each shown in Fig. 6 (1) to (V) above.
1 or by combining the steps in FIG. 6 (1) to (1) and FIG. 7 (Chrysanthemum (V)). When forming the connecting intermediate 1+'i H made of material, the mold +
91H1 or by heating and hardening only the front bow portion of the same layer t and 14J from the outside of the tube u5)'.

In this case, the surface layer of the intermediate layer for connecting portions becomes the above-mentioned hard layer for connecting portions, but the remaining portion remains in a gelled state.

In FIG. 9, which shows the connection portion of the coated optical fiber described in FIG. 3, a hard layer for the connection portion is also provided.

In Fig. 8 of Mil's book, a part (surface layer part) of the intermediate layer for the connection part is shown.
However, in FIG. 9, a silicone-based liquid resin is applied onto the intermediate layer tll for the connection portion, and by curing it, the connection portion is formed. A hard layer (181) is formed.

The hard layer for the connection part shown in FIG. 9 is obtained by forming the intermediate layer 41 for the connection part in FIG. 6(IV), and then forming the reinforcing resin 1105 for the connection part as shown in FIG. 6(V). It would be sufficient to form it between the sites.

In Fig. 1O showing the connection part of the coated optical fiber described in Fig. 4, the intermediate layer for the connection part and the reinforcing part for the connection part 1
5) A mucous membrane layer Q for the connecting portion is formed between the connecting portion and the connecting portion.

Figure 6 (IV) (V)
During the process (here, it is formed by applying a predetermined silicone thread coating onto the intermediate layer U for the connecting portion).

Note that (2) and (8) are connected at the connection parts not shown in Figures 2 to 5.
), (3) and O-tsu, (4) and Q5), (5) and Q-1, and (6) layer 19 are each made of the same or similar paulownia wood. The mutual outer diameters are also the same or almost equal. In FIGS. 8 to 10, the coating layer for the connection part,
The hard layer 0.8+ for the connection part and the coating layer 4 for the connection part are omitted, and the thickness of the intermediate layer 04) for the connection part made of II fluid gel material can be increased accordingly. be.

Of course, in this case, the intermediate connecting part 11u (14) can be formed by the molding method shown in Fig. 6, or by the molding method via the tube shown in Fig. 7. This is the connection part between coated optical fibers, and in this connection part, the fusion-spliced optical fiber +11 [+1 and the connection part intermediate 1+
/JIJ4) is formed.

This intermediate layer for the connection part has the same or similar moon phase as the intermediate layer [31+31, and the connection part in FIG.
Figure 6 (1) (n) QVI (V) or Figure 6 (
1) (It), Figure 7 (IV) It is created by going through steps -1- of (V).

FIG. 12 shows an example in which an intermediate layer U' for a connection part made of a fluid substance is formed in place of the intermediate layer A< for a connection part made of a non-flowable gel-like substance described above. In the figure, in the connection part of the coated optical fiber shown in Fig. 1, there is a connection part in the shape of a rib, a hollow, etc. between the core I layer for the connection part (8) and the reinforcing resin layer for the connection part 05). An intermediate layer u=I)' is interposed.

The austere part in Fig. 12 is created by going through the steps in Fig. 6 (1) (It) (phantom) and -L in Fig. 7 (1~''), and in the process in Fig. 7 (IV), tube (15)
A fluid substance (for example, modified silicone oil) is injected into the inside through an injector 03).

Of course, in FIGS. 2 to 5 (also at the mutual connection of the coated optical fibers shown in FIG.
, 14J (181 standard), the connected original fiber [11 (an intermediary theory Q-tl' for the connection part may be interposed between 11 and the reinforcing resin layer (15) for the connection part). In these cases, the steps shown in FIG. 6 (1) (II) (I) and FIG. An intermediate layer made of a non-flowing gel-like substance is interposed between the coated optical fibers and the hli strong resin layer provided on the outer periphery of the coated optical fibers.The optical fibers extend from each terminal of a pair of coated optical fibers to a predetermined length. The exposed ends of these optical fibers are brought into contact with each other and fusion spliced, and an intermediate layer for a connection portion made of a non-flowable gel-like substance or a flowable substance is formed on the outer periphery. It is characterized in that a reinforcing resin layer for a connecting portion is formed on the outer periphery of the intermediate layer for a connecting portion.

Therefore, in the case of the present invention, the characteristics of the unconnected part of the coated optical fiber and its connected part can be made equal or almost uniform, and as a result, the JI iγ1 vibration 1tA Nigel-like v/J quality can be This means that the same effect as a seamless core wire can be obtained in the coated optical fiber, which is considered to be dangerous, and a seamless optical cable can be realized.

[Brief explanation of the drawing]

Figures 1 to 5 are cross-sectional views of various coated optical fibers;
Figures (1) to (vl are longitudinal cross-sectional views showing the connecting portion of the coated optical fiber according to the present invention together with the connecting process, and Figure 7 θ
1') (V) is a vertical cross-sectional view showing the other side of the same as above, and FIGS. 8 to 12 are vertical cross-sectional views showing various embodiments of the coated optical fiber connection portion according to the present invention. fil...Optical fiber (2)...Coat layer (3)...Intermediate layer (4)...Reinforcement resin layer (5)...Hard layer ( 6)...Mucosa layer +71 A, +71 B...Coated optical fiber (8)...Foot eyebrow Q for connection part...Intermediate disease for connection part (non-i+iE Flowability) u M... Intermediate Al for connection part (Fluidity) 05)...
・・・tili strong resin layer for connection part a8e """ Hard layer for connection part Usu°°°°°Decoria rib for connection part Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. Figure 7 Hani

Claims (1)

[Scope of Claims] (1) A pair of coated optical fibers with an intermediate layer made of a non-flowing gel-like substance interposed between the optical fiber and a hli strong resin layer provided on the outer periphery thereof. Optical fibers are exposed for a predetermined length from each end, and the ends of these optical fibers are butted against IL11.
．． As the outer periphery of the connecting portion is made of a non-flowing gel-like substance or i:lif, an intermediate layer for the connecting portion is formed, and the intermediate layer for the connecting portion is The connection portion of the coated optical fiber has a reinforcing fat layer for the connection 311 formed on the outer periphery. (2) The intermediate layer of the coated optical fiber is a coating layer directly above the optical fiber, and a reinforcing resin on the outer periphery of the coating layer. between the layers (this is interposed, and the intermediate jV1 for the connection part is fused,
The reinforcing resin layer for the connecting portion is formed next to the coating layer for the connecting portion provided immediately above the end of the optical fiber in the connected state. range of the connection part of the coated optical fiber described in item 1. (3) The middle part of the coated optical fiber has a coating layer directly above the optical fiber and a layer directly below the reinforcing resin layer (therefore, more than the above-mentioned intermediate layer). The intermediate layer for the connection part is the 9-fiber end straight L of the fused MPa continuation-shaped JL (the coat for the connection part J+'r edge L provided here). This is formed, and the 1+li strong finger layer for the connection part is directly above the intermediate part 9 for the connection part (with the hard layer for the connection part provided here). The connection part 0 of the coated optical fiber described in Range 1 (4) The !; The end part is on the end part of the +IIJ4 material layer (this 11'!), and the end part of the hli strong resin layer for the connection part is on the end part of the reinforcing blfJ resin layer.Claim 3 W mentioned in section
t-covered optical fiber connection section. (5) The intermediate layer of the optical fiber to be shunted is interposed between the coating layer directly above the optical fiber and the mucous membrane layer immediately below the reinforcing resin layer, and the intermediate layer for the connection portion is IA! I! The bonded optical state is formed on the edge of the coating layer for the connection portion provided directly above the end of the fiber, and the strong resin layer for the connection portion is formed on the side of the coating layer for the connection portion provided directly above the intermediate layer for the connection portion. A connecting portion of a coated optical fiber according to claim 1, wherein the connecting portion is formed at the end of a mucous membrane. (6) The end of the coating layer for the connection part is the end of the coating layer.
2 (this is the end of the hli strong resin 1 finger ha r1 for the connection part; 4B is +1 on the end of the reinforcement II resin layer) or the connection part of the coated optical fiber according to item 5 (7) The intermediate layer and the connection part intermediate +l'j are essentially the same --i or The connection portion of the coated optical fiber according to any one of the ranges 1, 2, and 3. The connection portion of the coated optical fiber according to any of Claims 1 to 6. (9) The coating layer and the coating layer for the connection portion are mutually (same or similar). 00) The hard layer and the hard layer for the connecting portion are made of the same or similar material as in Patent A17. Claim 5: Connection of coated optical fibers according to claim 3 or 4.
Coated optical fiber connection section.