JPH0548446B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an optical fiber member comprising an optical fiber and a covering material surrounding at least a part of the outer circumference in the axial direction of the optical fiber, and a method for manufacturing the same.

Prior Art and its Problems Optical fibers made of, for example, quartz, multicomponent glass, synthetic resin, or the like are known. These are generally extremely thin and easily deform permanently when subjected to a force perpendicular to the fiber axis.
For example, those made of quartz or multi-component glass tend to break, and those made of synthetic resin tend to bend or break.

Therefore, in order to avoid permanent deformation (breakage, bending, etc.) during the distribution process or processing and handling of optical fibers, or to avoid hydrolysis and weakening due to moisture adhesion, optical fibers are generally coated with flexible synthetic resin (primary resin coating). coat).

However, when the optical fiber is actually used under conditions where it is frequently subjected to relatively large external forces, the synthetic resin coating described above is not strong enough to reliably prevent permanent deformation of the optical fiber. In addition, such synthetic resin coatings generally have a large clearance between them and the optical fiber, and since a slipping agent such as silicone is present in this clearance, the optical fiber is fixed when a large force is applied in the fiber axis direction. This will result in misalignment with the optical fiber.

Therefore, in order to protect the optical fiber from relatively large external forces or to fix the optical fiber against external forces, it has been conventional practice to encase the optical fiber with a ferrule. For example, an optical connector plug has the shape of an optical connector plug, and a ferrule is prepared that has a passage for inserting an optical fiber that is drilled with high precision in the center, and the optical fiber is inserted into the passage. Moreover, it is manufactured by fixing with adhesive. The optical fiber insertion passage is drilled with high precision to match the outer shape of the optical fiber as much as possible, but in order to insert the optical fiber, it is necessary to make the passage larger than the outer diameter of the optical fiber. As mentioned above, it is essential to use an adhesive to fix the optical fiber.

For this reason, conventional techniques for fixing optical fibers with ferrules have the drawbacks of not only complicating the process due to the use of adhesives, but also requiring a long time for the adhesive to solidify, and also resulting in poor product yields. It was hot.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide an optical fiber member in which the optical fiber is tightened by contacting a part of the inner circumferential surface of the enveloping material facing the outer circumferential surface of the optical fiber.

Another object of the present invention is to provide a method for manufacturing the optical fiber member of the present invention, which allows the optical fiber member of the present invention to be manufactured with extremely simple operations, in an extremely short period of time, and at a high yield.

Further objects and advantages of the present invention will become apparent from the description below.

According to the present invention, the above objects and advantages of the present invention are provided by a plastically deformable optical fiber comprising a hollow passage having a cross section larger than that of the optical fiber, and made of metal such as copper, zinc, lead, aluminum or synthetic resin. The optical fiber and the enveloping material are formed by passing an optical fiber through the enveloping material and applying stress from the outer periphery of the enveloping material in the meridian direction of the cross section of the optical fiber and in the direction parallel to the meridian. An optical fiber member comprising: a contact portion that faces the optical fiber in a meridian direction and directly tightens the optical fiber in a cross section perpendicular to the fiber axis of the optical fiber; A convergent part facing in both directions converges from the contact part, and a terminal end of the converging part is located closer to the optical fiber than the midpoint between the outer peripheral end of the optical fiber and the outer peripheral end of the enveloping material in the equator direction. This is achieved by an optical fiber member characterized in that the thickness of the enveloping material gradually increases from the contact portion to the convergence portion.

According to the present invention, the optical fiber member of the present invention includes a hollow passage having a cross section larger than the cross section of the optical fiber, and is made of a plastically deformable material such as a metal such as copper, zinc, lead, or aluminum or a synthetic resin. By inserting an optical fiber into the hollow passage of the encasing material and applying stress in the meridian direction of the cross section of the optical fiber and in the direction parallel to the meridian, the optical fiber is forming a contact part that directly tightens the optical fiber and a converging part that faces in both directions in the equator direction and converges from the contact part, facing each other in the meridian direction; The hollow space is located closer to the optical fiber than the midpoint between the outer peripheral end of the fiber and the outer peripheral end of the enveloping material, and the thickness of the enveloping material gradually increases from the contact part to the converging part. It can be manufactured by an optical fiber member manufacturing method characterized in that an optical fiber inserted into a passage is directly tightened with a covering material.

The pipe provided with the optical fiber passage used in the method of the present invention is made of a plastically deformable material. The plastically deformable material deforms the optical fiber insertion passage of the pipe when stress is applied to opposing circumferential surfaces of the pipe using the method of the present invention, and tightens the optical fiber even when the stress is released. It is possible to maintain sufficient deformation to Preferred examples of such materials include copper, zinc, lead, aluminum, alloys containing these metals, metals such as brass, and suitable synthetic resins.

The pipe has at least one hollow passage for passing the optical fiber therethrough. The external shape of the pipe can be any shape, such as a round, elliptical, or square cross-sectional profile. The optical fiber insertion passage may have any cross-sectional shape as long as it has a space through which the optical fiber can be inserted or accommodated. The hollow passage can have, for example, a round, oval or square cross-sectional shape.

Preferably, the pipe has a round or oval cross-sectional profile and the hollow passage has a round or oval cross-sectional profile. The optical fiber passage or hollow passage preferably has a smooth inner surface and extends smoothly in its longitudinal direction toward both ends.

The wall thickness of a pipe having an optical fiber passageway varies depending on its material, etc., but when stress is applied to opposing circumferential surfaces of the pipe according to the method of the present invention, the passageway undergoes plastic deformation. Should be thick. Specifically, a pipe has an average wall thickness of approximately 0.1 to 2.5 mm (defined as the diameter when the area according to the outer circumference contour is a circle minus the diameter when the area according to the passage contour is a circle). ). The pipe can also have a hollow passage in a cross section perpendicular to its axial direction, for example, with an average diameter of about 0.2 to about 4.8 mm. Also, the pipe is approximately 1
Can have a length of ~100mm. The above-mentioned average diameter means the diameter when the area obtained by subtracting the area due to the passage contour from the area due to the outer peripheral contour is a circle.

In the method of the present invention, an optical fiber is first inserted into the hollow passage of the pipe as described above. According to the method of the invention, these passages can then be deformed to a size that allows for the insertion of optical fibers with sufficient clearance, thus preventing the accidental breakage of thin optical fibers during insertion of the optical fibers. can be prevented as much as possible.

Preferably, the average diameter of the hollow passages of the pipe is
Approximately the diameter of the optical fiber inserted through the passage
It has 1.001 to 60 times.

In the method of the present invention, stress is then applied to the pipe through which the optical fiber is inserted.

Stresses need to be applied to opposing circumferential surfaces of at least a portion of the pipe surrounding the optical fiber in a meridian direction of the cross-section of the optical fiber and in a manner parallel to the meridian. The meridian direction of the cross-section of the optical fiber is to be understood as an imaginary line passing through the center of the cross-section of the optical fiber. Therefore, the pipe extends exactly 180° of the pipe in the meridian direction passing through the center of the cross-section of the optical fiber and in a direction parallel to this.
A force of exactly the same magnitude and in a completely opposite direction is applied from the displaced circumferential surface. In the present invention, it is extremely important to apply stress as described above. That is, with respect to the pipe, in each of multiple directions (for example, two directions (for example, the meridian direction and the equator direction) passing through the center of the cross section of the optical fiber, from the circumferential surface of the pipe that is exactly 180 degrees away from the pipe, there are completely opposite directions of exactly the same size. If the force is applied, breakage of the optical fiber cannot be avoided. The reason for this is not clear, but it is probably because when stress is applied, a large force in the opposite direction perpendicular to the fiber axis acts on the optical fiber at different positions in the fiber axis direction.

According to the method of the present invention, when stress is applied as described above to a pipe with an optical fiber inserted into the passage, the passage, that is, the hollow passage deforms inward in the direction of the applied stress, and the optical fiber is inserted into the passage. This leads to tightening the optical fiber. The deformation of the passage must be performed at least until both inner surfaces of the optical fiber facing each other in the meridian direction come into contact with the outer surface of the optical fiber. This can be done until the inner surfaces of the two surfaces come into contact. The stress can be, for example, approximately 1 to 800 kg per unit area (mm ² ) of the peripheral surface that ultimately receives the load. The stress is preferably about 10 to 500 Kg/mm ² , more preferably about 50 to 500 Kg/mm 2
It is 300Kg/ ^mm2 .

The stress is applied to opposing peripheral surfaces of the pipe surrounding the optical fiber, in whole or in part in the axial direction. In other words, it is possible to apply stress to the opposing circumferential surfaces of the pipe all along the axial direction, deforming the opposing circumferential surfaces of the pipe throughout the entire axial direction, and also to apply stress to the opposing circumferential surfaces of the pipe. ,
It is also possible to apply stress only to a portion in the axial direction, for example, the central portion in the axial direction, and to deform the opposing circumferential surfaces of the pipe only in a portion in the axial direction, such as the central portion.

According to the latter method of deforming only the axial center of the pipe, the optical fiber can be positioned approximately at the center of the undeformed end of the pipe (the center of the passage in the axial cross section). In addition, according to the latter method, which applies stress only to a part of the pipe in the axial direction, it is possible to apply stress to the pipe intermittently. An undeformed portion can be provided to alleviate the strain. If the pipe is relatively long, it is desirable to apply stress intermittently as described above.

Further, the stress applied to the opposing circumferential surfaces of at least a portion of the pipe can be applied simultaneously or sequentially along the axial direction of the pipe.

In other words, the stress is applied to the stress-receiving area of the pipe and the pressing surface of the device that applies the stress, either simultaneously over the entire axial direction of the pipe or gradually along the axial direction of the pipe, for example, starting from the center of the pipe. It can be applied to opposing circumferential surfaces of the pipe by contacting the pipe beginning and progressing toward the ends.

The stress applied to at least some opposing circumferential surfaces of at least some opposing circumferential surfaces of the pipe is
It is preferable to control so that the stress applied to the center of the circumferential surface along the axial direction of the pipe is applied earlier than the stress applied to both ends of the circumferential surface. By controlling in this way, the axial strain that occurs in the pipe when it is deformed can be released from the center toward the ends, preventing the optical fiber from breaking, and the method of the present invention can be carried out advantageously. can do. In addition, in the method of the present invention, after or before tightening the optical fiber by applying stress, the optical fiber slightly protruding from one end of the enveloping material is heated and melted, and the optical fiber is exposed to light at the end. It is also possible to form a convex curved surface made of the fiber material, such as a convex lens shape, a convex ellipse shape, a convex spherical shape, etc. This convex curved surface is a curved surface in the same way that the liquid creates various convex curved surfaces at the tip of the capillary. By forming a convex curved surface, the end of the optical fiber can be polished without polishing.
This provides the advantage of effectively transmitting and receiving light through the end of the optical fiber.

The above-mentioned method of the present invention provides a covering material, that is, a pipe having an optical fiber insertion passage that covers at least a part of the outer circumferential surface of the optical fiber along the fiber axis of the optical fiber. 2, including at least one pressing surface movable in any direction parallel to this, capable of applying stress to opposing circumferential surfaces of at least a portion of the enveloping material; This can be easily carried out by using a pressing member having two pressing surfaces.

The pressing member has two pressing surfaces as described above. At least one of the two pressing surfaces is movable toward each other.

The two pressing surfaces are movable relatively to each other on a common virtual axis, and furthermore, when pressing opposing circumferential surfaces of the pipe, the opposing circumferential surfaces have exactly the same size. It has a surface shape that causes stress in the opposite direction. For example, two pressing surfaces each having a flat surface shape substantially perpendicular to the virtual axis as described above, or two having a thin groove along the axial direction of the pipe in the flat surface shape. These pressing surfaces can be employed as the pressing surfaces of the pressing member. According to research conducted by the present inventor, a particularly preferable pressing surface is such that the central part of the surface of the optical fiber that finally comes into contact with the enveloping material in the fiber axial direction applies stress to the encasing material earlier than the end part. It was revealed that the structure was configured so that it could be added. Such a pressing surface is gently curved so that, for example, the center portion of the surface that will eventually come into contact with the wrapping material swells more than the end portions in the direction of contact with the wrapping material.

Thus, according to the present invention, as described above,
An optical fiber member consisting of at least one optical fiber and a covering material surrounding at least a part of the outer periphery in the axial direction of the optical fiber, the covering material in a cross section perpendicular to the fiber axis of the optical fiber. The optical fiber is tightened with both inner surfaces facing the optical fiber in the meridian direction, and at least one of the inner surfaces of the enveloping material has at least a minute gap with the outer peripheral surface of the optical fiber in the equatorial direction. It will be appreciated that there is provided an optical fiber member of the present invention characterized in that it comprises:

As described above, the optical fiber member of the present invention includes:
The optical fiber is characterized by its cross-sectional structure perpendicular to the fiber axis. That is, in the optical fiber member of the present invention, in the above-mentioned cross section, both inner surfaces of the enveloping material facing the optical fiber in the meridian direction of the optical fiber are in close contact with the optical fiber and tightened, and At least one of the inner surfaces of the enveloping material has at least a minute gap with the outer circumferential surface of the optical fiber (in a direction perpendicular to the meridian direction and passing through the center of the optical fiber). In other words, the cross section of the optical fiber member of the present invention includes both surfaces that are in close contact with the optical fiber in a direction passing through the center of the optical fiber, and a surface that is not in contact with the optical fiber in a direction that intersects this direction. An enveloping material having a diameter is present together with the optical fiber.

The number, size, and shape of the gaps existing in the equator direction vary depending on the material and type of the wrapping material, the shape of the passage in the wrapping material, or the degree of deformation of the passage. For example, the optical fiber member of the present invention can have two gaps at opposing positions in the equator direction, and the shapes can be substantially similar. Further, the gap on one side is about 0.001 to about 150 times, preferably about 0.001 to about 75 times, more preferably about 0.1 times the cross-sectional area of the optical fiber.
It can have a cross-sectional area of ~10 times.

The optical fiber member of the present invention has a covering material having various external shapes that reflect the surface structure depending on the structure of the pressing surface of the crimping tool used in manufacturing the optical fiber member. For example, the inner surface clamping the optical fiber and the opposing outer surfaces may both be substantially flat along at least a portion of the optical fiber axis, or both may be substantially flat along the optical fiber axis; For example, it is a surface consisting of two extending substantially flat surfaces and a convex surface extending in the optical fiber axis direction located between the two flat surfaces.

The enveloping material may also tighten the optical fiber along the entire length of the encapsulant along the optical fiber axis, or may tighten the optical fiber in the center of the encasing along the axis of the optical fiber. The optical fiber may be released from tightening at both ends of the wrapping material.

The enveloping material has a length of, for example, about 1 to 100 mm in the axial direction of the optical fiber, and tightens the optical fiber over a length of, for example, at least about 1 to 50 mm in the axial direction of the optical fiber.

Further, in the optical fiber member of the present invention, the distance between the opposite end edges in the equatorial direction can be, for example, about 0.25 to about 5 mm in a cross section perpendicular to the fiber axis.

In the present invention, the optical fiber is, for example, quartz,
It is a multi-component glass or a synthetic polymer, and can be used without being limited by the material. Optical fibers made of multi-component glass are disclosed, for example, in Japanese Patent Publication No. 51-29524, Japanese Patent Application Laid-open No. 3352-1982, Japanese Patent Application Laid-open No. 3354-1983, or Japanese Patent Application Laid-open No. 60240-1989. Optical fibers made of synthetic polymers are disclosed, for example, in Japanese Patent Application Laid-Open No. 103504/1983.

In the present invention, it is preferable to use an optical fiber that is composed of a core and a cladding and whose cross section perpendicular to the fiber axis is substantially circular, and the outer diameter of the cross section is, for example, about 50 to 1000 μm, preferably about 100 μm. It can be ~600μ.

The optical fiber member of the present invention has a covering material on at least one end of the optical fiber, and the optical fiber has a convex curved surface at at least one end having the covering material. be able to. Such a convex curved surface is effective for efficiently irradiating and receiving light due to the convex lens effect.

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to the accompanying drawings in which specific embodiments are illustrated.

FIG. 1 shows an example of a pipe having an optical fiber passage for use in the method of the present invention. FIG. 1 shows a pipe 1 having a round cross-section and having one hollow passage 2 having a round cross-section. From this example, other examples of pipes used in the method of the present invention will be easily understood in conjunction with the above description.

FIG. 2a shows a state in which the optical fiber 3 is inserted into the hollow passage 2 of the pipe 1 shown in FIG. It can be seen that the hollow passage 2 has a space between the outer peripheral surface of the optical fiber 3 and the inner surface of the hollow passage 2. FIG. 2b is a schematic illustration of how stress is applied to the pipe 1 in the state shown in FIG. 2a. Also, the second c.
2d and 2e both illustrate axial cross sections of the optical fiber member of the present invention. Second
The method of the present invention will be specifically explained using figures a, 2b, 2c, 2d and 2e.

The pipe 1 (Fig. 2a), in which the optical fiber 3 is inserted into the hollow passage 2, receives forces F and F' of exactly the same magnitude and in opposite directions in the meridian direction passing through the center of the optical fiber 3 (Fig. 2b). ). When stresses F and F' sufficient to plastically deform the pipe 1 are applied, the pipe 1 begins to deform, and the inner surface 21 of the passage 2 and the outer circumferential surface 31 of the optical fiber 3 as shown in FIG.
The two contact each other in the meridian direction of the optical fiber 3, and if the stress is continued, the second
The deformation progresses further as shown in Fig. d and Fig. 2e, and the gap formed in the equator direction between the inner surface 21 of the passage 2 and the outer circumferential surface 31 of the optical fiber 3 becomes smaller than the state shown in Fig. 2c. becomes even smaller. The conditions illustrated in FIGS. 2c, 2d, and 2e are the conditions in which stresses F and F' are applied by two substantially flat pressing surfaces (not shown), and the deformed The meridional outer surface of the pipe 1 is substantially flat.

FIG. 3a shows, for the pipe 1 in the state shown in FIG. 1, substantially flat planes P ₁ , P ₁ ' and curved surfaces P 2 , P ₁ ' extending along the axial direction of the pipe at the center thereof.
The state in which the pressing surfaces having grooves having P ₂ ' are in contact is shown as a schematic explanatory diagram. In this case, the stress F (same for F') is the stress f 1 , f 2 in the direction parallel to the meridian direction of the optical fiber from the contact area t ₁ , t ₂ between the pressing surface and the pipe ₁ , _respectively .
It will be appreciated that first added to pipe 1 as .

From the state shown in FIG. 3a, the two pressing surfaces P ₁ ,
When P ₁ ′ moves closer, pipe 1
begins to deform, and the inner surface 21 of the passageway 2 and the outer surface 31 of the optical fiber 3 come into contact in the meridian direction of the optical fiber 3, as shown in FIG. 2c, and finally, as shown in FIG. 3b. As shown, a small gap is left in the equator direction and the pressing surface P ₁ (P ₁ ′)
and an optical fiber member having an outer surface in the meridian direction having a flat surface 11 extending in the axial direction and a convex portion 12 reflecting the surface structure of P ₂ (P ₂ ').

Although the grooves on the pressing surface in FIG. 3a have a semicircular cross section in the direction perpendicular to the axial direction, the grooves may have other shapes such as a shallow semicircle, a U-shape, or a polygonal shape such as a triangle. . The groove width (width of the open portion) perpendicular to the axial direction is preferably larger than the diameter of the optical fiber.

FIG. 4a schematically shows a state in which the pressing surfaces P ₁ and P ₁ ', which are gently convex in the axial direction of the pipe 1, are in contact with the pipe 1 at the axial center of the pipe 1. has been done. When the pressing surfaces P ₁ , P ₁ ' approach further from the state shown in FIG. 4a, the pressing surfaces P ₁ ,
Due to P ₁ ', the pipe 1 and the passage 2 begin to deform from the center in the axial direction, and the deformation gradually progresses toward the ends.

It will be understood that according to the embodiments of FIGS. 4a and 4b, the pressure applied to the center of the circumferential surface of the pipe along the axial direction of the pipe is applied faster than the stress applied to both ends of the circumferential surface. . Such stress can also be applied by using a pipe as shown in FIG. 6, in which the outer diameter of the central portion is larger than the outer diameter of both ends.

FIG. 6 shows an example of a crimping tool for a covering member that can be used when manufacturing the optical fiber member of the present invention.

In FIG. 6, reference numerals 72 and 72' denote a pair of handles, which are mutually pivotally connected to levers 73 and 73' by pins 81 and 81', respectively. Lever 7 connected by pins 81, 81'
3, 73' and the handles 72, 72' form a pair of arms. The handles 72, 72' are pivotably connected to each other by a pin 80, and the levers 73, 73' are connected to a lever support 74 by pins 82, 82'. lever 73,
73' can be pivoted about pins 82 and 82', respectively. The levers 73, 73' do not use the lever support 74, but are provided with connecting portions 84, 84', respectively, as shown in FIG. They can also be pivotably coupled.

Thus, the arm 71 consisting of the lever 73 and the handle 72 and the lever 73' and the handle 7
It will be understood that the arms 71' consisting of the arms 71' and 2' form a pair of arms that are pivotally connected to each other.

One end of the lever 73, 73', that is, the arm 71,
A pressing member 75 is rotatably connected to one end of 71' by pins 83 and 83', respectively.

The pressing member 75 includes base parts 90, 90', base parts 90,
90' and pressing surfaces 92, 9, respectively.
It consists of pressing actuating parts 91, 91' having 2' and a guide member 93. The guide member 93 guides the pipe through which the optical fiber is inserted into the pressing surfaces 92, 92'.
It has an opening 94 for feeding between the two. The guide member 93 is, for example, a cylinder, and the pressure actuating parts 91, 91' are, for example, pistons that can slide in the channel of the cylinder in the direction of its longitudinal axis.
Cylinder 93 is connected to piston 91 in sliding relationship with either piston 91 or 91'.
and 91' relative movement only on a common axis, and piston 91 or 91'.
It is also possible to provide such a movement of the piston in a fixed relationship to either one of the pistons 1' and slidable relative to the other.

An enlarged perspective view of the opening of FIG. 6 is shown in FIG. According to FIG. 8, the pressing surfaces 92 and 92' have grooves 95 and 95', respectively, and a pipe having an optical fiber inserted therein can be positioned between the pressing surfaces 92 and 92' in the through opening 94. It will be understood that this is extremely easy.

The crimping tool shown in FIG.
The handles 72, 72' are operated by positioning the pipe with the optical fiber inserted therebetween, and then bringing the handles 72, 72' closer to each other, for example by grasping them by hand. The mutual approach of the handles 72, 72' causes a pivot about the pin 80, which pivots through the pins 81, 81' to the levers 73, 7.
3', the levers 73, 73' pivot around the pins 82, 82', respectively, and the pivoting is transmitted to the pressing member 75 through the pins 83, 83' to move the pressing surfaces 92, 92' closer to each other. Let's go. Thus,
The pipe into which the optical fiber is inserted, which is located between the pressing surfaces 92 and 92', is pressed by the pressing surface in either the meridian direction or a direction parallel to this in a cross section perpendicular to the fiber axis of the optical fiber, An optical fiber member of the present invention is provided.

According to the crimping tool of the present invention having pressing surfaces 92, 92' having grooves 95, 95' shown in FIG.
It is understood that an optical fiber member of the present invention having the cross-sectional shape shown in FIG. 3b can be obtained.

The optical fiber member of the present invention has an extremely simple structure and securely fixes the optical fiber by tightening it with a covering material. The optical fiber member of the present invention reliably protects the easily-breakable optical fiber from stress applied in the fiber axis direction and the direction perpendicular to the fiber axis, thereby greatly expanding the application of optical fibers to various fields of use.

For example, FIG. 9 shows an example in which the optical fiber member of the present invention is incorporated into an optical connector plug.

The optical connector plug 50 includes a molded ferrule 51 and a holder 52 that constitute the plug. The ferrule 51 has a stepped cylindrical shape, and is provided with a wide diameter hole 51a that fits into the holder 52 and a narrow diameter hole 51b through which the optical fiber member of the present invention is inserted. A hole 54 through which the optical fiber 3 can be inserted is provided. The optical fiber member of the present invention, which is composed of an optical fiber 3 and a wrapping material 1, has a small diameter hole 51b in a portion A where the optical fiber is tightened with the wrapping material.
fitted inside.

A portion of the optical fiber 3 slightly protruding from one end of the enveloping material 1 is inserted into a hole 54 in the tip 53 of the ferrule 51.

The holder 52 has a substantially cylindrical shape, and the optical fiber cable 33 (optical fiber 3
(covered with a flexible coating 34) through which a wide diameter hole 52a is inserted, and a small diameter hole 52b into which the end 10a of the wrapping material is fitted and fixed.
The narrow hole 52b has a stepped structure, and the end 10a of the covering material is fixed by the step 52c.

To assemble the optical connector plug 50 shown in FIG. 52
a to the cable 33, insert a covering material into the optical fiber 3 from the distal end side, that is, a pipe provided with a passage through which the optical fiber is inserted, and then attach the holder 52.
The enveloping material is brought into contact with the step 52c of the small diameter hole 52b, and then the length A portion of the enveloping material 1 is crimped by the method of the present invention to tighten the enveloping material and the optical fiber together. Then, the collar 55, washer 56, and cushion 57 are attached to the holder 52, and the ferrule 51 is inserted until its wide diameter hole 51a is firmly fitted into the holder 52 and its narrow diameter hole 51b is firmly fitted into the wrapping material 1. Finally, the tip of the optical fiber slightly protruded from the nozzle 54 is polished to make the tip of the optical fiber a mirror surface.

In another embodiment of the optical connector plug using the optical fiber member of the present invention, the optical connector plug 5
The tip of the 0 can also be made as shown in FIG. 10, for example.

In the embodiment of FIG. 10, in the optical fiber member of the present invention, the tip of the optical fiber 3 has a spherical shape 3a.
It is processed into. The tip of the optical fiber 3 can be easily processed into a spherical shape by melting the tip of the optical fiber. Such processing is extremely easy when the optical fiber is made of multi-component glass. The optical fiber member of the present invention having a spherical tip has a great effect of converging light emitted from the tip due to the lens action of the convex surface, and is useful for minimizing optical signal loss.

Effects According to the present invention, it is possible to effectively prevent the optical fiber from breaking when forming the optical fiber member.

Furthermore, the present invention has the effect that the force for fixing the optical fiber can be maintained constant over a long period of time since the enveloping material is largely plastically deformed.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of an example of a pipe used in the present invention. FIG. 2a is a schematic cross-sectional view showing a state in which an optical fiber is inserted into the hollow passage of the pipe shown in FIG. 1. FIG. 2b is a schematic explanatory diagram for explaining how stress is applied to the pipe in the state shown in FIG. 2a. Figures 2c, 2d, and 2
Figure e is a schematic cross-sectional view of an example of the optical fiber member of the present invention. FIG. 3a is a schematic explanatory view of a different aspect from FIG. 2b for explaining how stress is applied by a pressing surface having grooves to the pipe in the state of FIG. 2a. FIG. 3b is a schematic cross-sectional view of the optical fiber member of the present invention obtained by the method shown in FIG. 3a. FIG. 4a is a schematic view showing a state in which the pressing surface, which is gently convex in the axial direction of the pipe, is in contact with the pipe. FIG. 4b is a schematic explanatory diagram for explaining a state in which the pressing surfaces further approach each other from the state shown in FIG. 4a, deforming the pipe and its passage. FIG. 5 is a schematic side view of an example of a pipe used in the present invention. FIG. 6 is a plan view showing an example of a crimping tool that can be used in manufacturing the optical fiber member of the present invention. FIG. 7 is a schematic view showing another way of connecting the arms of the crimping tool. 8 is an enlarged perspective view of the opening of the crimping tool of FIG. 6. FIG. FIG. 9 is a sectional view of an example of an optical connector plug assembled using the optical fiber member of the present invention. FIG. 10 is a sectional view of the tip of an optical connector plug using the optical fiber member of the present invention in which the tip of the optical fiber is processed into a spherical shape. DESCRIPTION OF SYMBOLS 1... Pipe, 2... Hollow passage, 3... Optical fiber, 21... Inner surface of passage, 31... Outer peripheral surface of optical fiber.

Claims (1)

[Claims] 1. An optical fiber is provided with a hollow passage having a cross section larger than the cross section of the optical fiber, and is made of metal such as copper, zinc, lead, aluminum, or synthetic resin and is plastically deformable. An optical fiber member consisting of an optical fiber and an enveloping material, which is formed by passing the optical fiber through the encasing material and applying stress from the outer periphery of the encasing material in the meridian direction of the cross section of the optical fiber and in the direction parallel to the meridian. In a cross section perpendicular to the fiber axis of the optical fiber, the enveloping material includes: a contact portion that directly tightens the optical fiber, facing each other in the meridian direction of the optical fiber; a converging part that converges, the terminal end of the converging part is located closer to the optical fiber than the midpoint between the outer peripheral end of the optical fiber and the outer peripheral end of the enveloping material in the equator direction, and the thickness of the enveloping material An optical fiber member characterized in that: is configured to gradually increase from the contact portion to the convergence portion. 2. The optical fiber member according to claim 1, wherein the two gaps have substantially similar shapes in a cross section perpendicular to the fiber axis of the optical fiber. 3. The optical fiber member according to claim 1, wherein the one gap has a cross-sectional area of about 0.001 to about 150 times the cross-sectional area of the optical fiber in a cross section perpendicular to the fiber axis of the optical fiber. 4. According to claim 1, the encasing material has two substantially flat outer circumferential surfaces facing each other along the axial direction of the optical fiber in at least a portion of the axial direction of the optical fiber. optical fiber components. 5 The above-mentioned enveloping material has two outer circumferential surfaces facing each other along the optical fiber axial direction in at least a part of the optical fiber axial direction, and each outer circumferential surface extends in the optical fiber axial direction. 2. An optical fiber member as claimed in claim 1, comprising two substantially flat planes and a convex surface located therebetween extending in the direction of the optical fiber axis. 6. The encasing material tightens the optical fiber along the optical fiber axis at the center of the encasing material and releases the optical fiber from the tension at both ends of the encasing material. The optical fiber member according to item 1. 7. The optical fiber member according to claim 1, wherein the enveloping material has a length of about 1 to about 100 mm in the axial direction of the optical fiber. 8. The optical fiber member according to claim 1, wherein the enveloping material tightens the optical fiber over a length of at least about 1 to about 50 mm in the axial direction of the optical fiber. 9. The optical fiber member according to claim 1, wherein the encasing material has a distance between opposing edges in the equatorial direction of about 0.25 to about 5 mm in a cross section perpendicular to the fiber axis of the optical fiber. 10. The optical fiber member according to claim 1, wherein the optical fiber has a substantially circular cross section in a direction perpendicular to the fiber axis. 11. The optical fiber member according to claim 1, wherein the optical fiber has an outer diameter of about 50 to about 1000 microns in a cross section perpendicular to the fiber axis. 12. The optical fiber member according to claim 1, wherein the material of the optical fiber is quartz or multi-component glass. 13. Claim No. 1, wherein the optical fiber has the above-mentioned enveloping material on at least one end thereof, and the optical fiber has a convex curved surface at at least one end having the above-mentioned enveloping material. The optical fiber member according to item 1. 14. The optical fiber member according to claim 1, wherein the optical fiber is a single optical fiber consisting of a core and a cladding. 15 The optical fiber is inserted into the hollow passage of the enveloping material, which is provided with a hollow passage having a cross section larger than the cross section of the optical fiber, and is made of a plastically deformable material such as a metal such as copper, zinc, lead, or aluminum or a synthetic resin. , directly tightening the optical fibers in a cross-section perpendicular to the fiber axis of the optical fibers, opposite each other in the meridian direction, by applying stress to the cross-sections of the optical fibers in the meridian direction and in directions parallel to the meridian; forming a contact portion and a convergence portion that converges from the contact portion in both directions in the equator direction, and the end of the convergence portion is located between the outer peripheral end of the optical fiber and the outer peripheral end of the wrapping material in the equator direction; The optical fiber inserted into the hollow passage is placed on the side of the optical fiber from the point, and the thickness of the enveloping material gradually increases from the contact part toward the convergence part, so that the optical fiber inserted into the hollow passage is surrounded by the enveloping material. A method for producing an optical fiber member characterized by direct tightening. 16 The stress applied to at least some opposing circumferential surfaces of the enveloping material is such that the stress applied to the center of the circumferential surface along the axial direction of the enveloping material is applied to both ends of the circumferential surface. 16. The method according to claim 15, wherein the method is controlled so that the stress is applied faster than the applied stress. 17. The method of claim 15, wherein the enveloping material has a substantially circular hollow passage in a cross section perpendicular to its axial direction. 18. The method of claim 15, wherein the enveloping material has, in a cross section perpendicular to its axial direction, a hollow passage having an average diameter of about 0.2 to about 4.8 mm and an average wall thickness of about 0.1 to 2.5 mm. . 19. The method of claim 15, wherein the passageway of the wrapping material extends smoothly in its longitudinal direction. 20. The method of claim 15, wherein the wrapping material has a length of about 1 to 100 mm. 21 The average diameter of the hollow passages of the wrapping material is approximately the diameter of the optical fibers inserted through those passages.
16. The method according to claim 15, which is 1.001 to 60 times. 22 Claims that include inserting an optical fiber into the passageway of the covering material and applying a stress of about 1 to 800 Kg/mm ² to the opposing circumferential surfaces of the covering material that will ultimately receive the load. The method according to paragraph 15. 23. The method according to claim 15, wherein stress is applied to opposing circumferential surfaces of the wrapping material by pressing surfaces having a surface shape different from that of the circumferential surfaces. 24. The method according to claim 15, wherein either before or after tightening, the optical fiber is heated and melted to form a convex curved surface at one end of the enveloping material.