JP6833465B2 - Optical connector structure - Google Patents

Description

The present invention relates to an optical connector structure.

In a device that transmits laser light, it is necessary to suppress heat generation due to the laser light from the viewpoint of device protection. For example, in Patent Document 1, at the tip of an optical fiber whose core is coated with inner and outer coating resins, a portion where the inner and outer coating resins are peeled off to expose the core and an outer coating resin are peeled off. By providing a portion where the inner coating resin is exposed and emitting laser light leaking from the core from the portion where the inner coating resin is exposed to the outside, it is possible to suppress heat generation of the inner and outer coating resins. It is disclosed.

International Publication No. 2013/153734

As shown in FIG. 13, in the optical connector structure C'configured at the tip of the optical fiber core wire 10'for laser light transmission, the optical fiber core wire 10'is inserted into the tubular optical connector 20'. The optical fiber core wire 10'can be mechanically fixed to the optical connector 20' by internally fitting the core wire fixing member 30'and crimping the tip portion thereof. Further, in such an optical connector structure C', when the clad mode light propagating through the clad 11b'without being incident on the core 11a' of the optical fiber 11' escapes to the jacket 12', the core wire fixing member 30 is used. It can be expected that the heat generation of the jacket 12'is suppressed by absorbing it with'and releasing it as heat to the outside through the optical connector 20'. However, since the thickness of the jacket 12'is usually thin, when the jacket 12'is crimped by the core wire fixing member 30', the core wire fixing member 30'is pushed into the jacket 12' and the inside of the jacket 12' is pushed. The optical path of the propagating clad mode light is blocked. As a result, a large amount of clad mode light that has lost its place is emitted in the vicinity of the core wire fixing portion, so that the nearby jacket 12'and the core wire fixing member 30'are rapidly heated to generate heat, which may cause damage. I am concerned.

An object of the present invention is to provide an optical connector structure capable of safely and efficiently removing clad mode light.

The present invention comprises an optical fiber core wire having an optical fiber including a core and a clad and a jacket covering the optical fiber, a tubular optical connector provided at an end of the optical fiber core wire, and the optical fiber. An optical connector structure including a tubular core wire fixing member for fixing the optical fiber core wire to the optical connector by inserting the core wire and internally fitting and crimping the optical connector. An overcoat layer that covers the optical fiber core wire is interposed between the optical fiber core wire and the core wire fixing member.

According to the present invention, an overcoat layer is interposed between the optical fiber core wire and the core wire fixing member, and the core wire is added by adding the thickness of the overcoat layer in addition to the thickness of the jacket. The optical path (cross-sectional area) of the clad mode light propagating in the jacket is secured even in the vicinity of the fixed portion, and the local emission of the clad mode light is suppressed. Further, by adding the thickness of the overcoat layer in addition to the thickness of the jacket, the clad mode light removed by the action of the overcoat layer is reflected by the core wire fixing member and returned to the optical fiber, and is clad again. It is possible to suppress the mode light. As a result, local heat generation at the core wire fixing portion can be suppressed, and clad mode light can be safely and efficiently removed.

It is a vertical sectional view of the optical connector structure which concerns on Embodiment 1. FIG. It is a vertical sectional view of the main part of the optical connector structure which concerns on Embodiment 1. FIG. It is a perspective view of the optical fiber core wire. It is 1st explanatory drawing of the method of forming an overcoat layer in Embodiment 1. It is a 2nd explanatory drawing of the method of forming an overcoat layer in Embodiment 1. It is a front view of the core wire fixing member. It is a side view of the core wire fixing member. FIG. 5A is a sectional view taken along line VC-VC in FIG. 5A. It is explanatory drawing which shows the method of fixing the optical fiber core wire to an optical connector. It is a vertical sectional view of the main part of the optical connector structure which concerns on Embodiment 2. FIG. It is a vertical sectional view of the main part of the optical connector structure which concerns on Embodiment 3. FIG. It is a vertical sectional view of the main part of the optical connector structure which concerns on Embodiment 4. FIG. It is 1st explanatory drawing of the method of forming an overcoat layer in Embodiment 4. It is a 2nd explanatory drawing of the method of forming an overcoat layer in Embodiment 4. It is a 3rd explanatory drawing of the method of forming an overcoat layer in Embodiment 4. It is a 4th explanatory drawing of the method of forming an overcoat layer in Embodiment 4. It is a vertical cross-sectional view of the main part of the optical connector structure which concerns on Embodiment 5. It is a vertical sectional view of the main part of the optical connector structure which concerns on Embodiment 6. It is a vertical sectional view of the main part of the optical connector structure which does not have an overcoat layer.

Hereinafter, embodiments will be described in detail with reference to the drawings.

(Embodiment 1)
1 and 2 show the optical connector structure C according to the first embodiment. The optical connector structure C according to the first embodiment is configured at, for example, an incident end and / or an emitted end of an optical fiber cable for laser light transmission in a laser processing machine or the like.

The optical connector structure C according to the first embodiment includes an optical fiber core wire 10, an optical connector 20 provided at an end thereof, and a core wire fixing member 30 interposed between them.

FIG. 3 shows an optical fiber core wire 10.

The optical fiber core wire 10 has an optical fiber 11 and a jacket 12 that covers the optical fiber 11. The outer diameter of the optical fiber core wire 10 is, for example, 1.3 mm.

The optical fiber 11 has a core 11a having a relatively high refractive index and a clad 11b having a relatively low refractive index covering the core 11a. In the optical fiber 11, for example, the core 11a is made of pure quartz glass, and the clad 11b is made of quartz glass doped with a dopant that lowers the refractive index such as fluorine. The outer diameter of the optical fiber 11 is, for example, 500 μm. The diameter of the core 11a is, for example, 100 μm. The numerical aperture (NA) of the core 11a is, for example, 0.20. The optical fiber 11 may have a support layer that further covers the outside of the clad 11b.

The jacket 12 is made of, for example, a light-transmitting resin. The jacket 12 may be composed of a single layer, or may be composed of two layers, an inner resin layer and an outer resin layer. Examples of the resin material forming the single-layer jacket 12 include an ultraviolet curable resin and a thermosetting resin. Examples of the resin material forming the inner resin layer of the two-layer jacket 12 include silicone resin. Examples of the resin material forming the outer resin layer of the two-layer jacket 12 include nylon resin and fluororesin (tetrafluoroethylene resin and the like). The thickness of the jacket 12 is, for example, 0.1 mm or more and 0.3 mm or less.

The optical fiber core wire 10 includes a fiber exposed portion 10a on the distal end side where the jacket 12 is peeled off and the optical fiber 11 is exposed, and a jacket covering portion 10b covered with a continuous jacket 12 on the rear side thereof. There is.

A mode stripper 13 is provided on the outer peripheral surface of the exposed optical fiber 11 in the fiber exposed portion 10a. Here, the mode stripper 13 means a processed shape for emitting light propagating in the clad 11b of the optical fiber 11 to the outside of the optical fiber 11. Specifically, the mode stripper 13 is formed by, for example, machining the outer peripheral surface of the optical fiber 11 by machining such as polishing or cutting, chemical etching, laser processing, or depositing and melting fine particles such as silica. It is composed of the formed rough surface.

The optical fiber core wire 10 is integrally provided with an overcoat layer 40 so as to cover the boundary portion between the fiber exposed portion 10a and the jacket covering portion 10b. Therefore, the portion of the optical fiber core wire 10 covered with the overcoat layer 40 includes a portion where the jacket 12 is peeled off and the optical fiber 11 is exposed. The coating length of the fiber exposed portion 10a by the overcoat layer 40 is shorter than the coating length of the jacket coating portion 10b. The overcoat layer 40 is formed of, for example, a resin material of a light-transmitting ultraviolet curable resin, a thermosetting resin, or a thermoplastic resin. As shown in FIG. 4A, such an overcoat layer 40 is formed in a mold 51 in which a cavity 51a in the shape of the overcoat layer 40 is formed, and the fiber exposed portion 10a and the jacket covering portion in the optical fiber core wire 10 are formed. The boundary portion with 10b is set, and as shown in FIG. 4B, it can be formed by injecting a liquid resin material 40'forming the overcoat layer 40 into the cavity 51a and curing it. Further, the overcoat layer 40 can also be formed by sequentially applying resin on the jacket 12 and hardening the jacket 12 without using the mold 51.

The optical connector 20 is formed in a tubular shape. The main body of the optical connector 20 is made of a metal such as stainless steel. Inside the optical connector 20, a fiber accommodating portion 21 formed of a cylindrical hole-like space formed so as to extend in the length direction is provided in the intermediate portion. An annular sealing member 22 is internally fitted at the tip of the fiber accommodating portion 21.

Behind the fiber accommodating portion 21 inside the optical connector 20, a core wire fixing member accommodating portion 23 formed of a conical hole-shaped space whose inner diameter is gradually expanded is provided. On the tip side of the fiber accommodating portion 21 inside the optical connector 20, a block accommodating portion 24 formed of an opening space formed so as to be continuous with the optical connector 20 is provided. A quartz block 25 is housed in the block housing part 24.

5A to 5C show the core wire fixing member 30.

The core wire fixing member 30 is formed in a cylindrical shape having a conical outer shape. The core wire fixing member 30 is made of, for example, a metal such as phosphor bronze, brass, copper, aluminum, or stainless steel. A core wire insertion hole 31 is provided inside the core wire fixing member 30. A cross-shaped grind 32 is provided on the tip end side portion of the core wire fixing member 30 when viewed from the front. The inner wall of the core wire insertion hole 31 is configured with an uneven surface 31a in which grooves having a V-shaped cross section extending in the circumferential direction are continuously provided in the length direction corresponding to the portion where the slit 32 is provided. .. The surface of the core wire fixing member 30 may be plated with a metal having good thermal conductivity such as gold, silver, or platinum for the purpose of lowering the thermal resistance and improving the heat dissipation. The plating thickness is 0.1 μm or more and 100 μm or less, preferably 1 μm or more and 10 μm or less.

In the optical connector structure C according to the embodiment, the end portion of the optical fiber core wire 10 is inserted in order from the rear of the core wire fixing member 30 and the optical connector 20, and the optical fiber 11 of the fiber exposed portion 10a is a fiber accommodating portion. It is provided so as to extend the central axis position of 21, its tip is inserted into the sealing member 22, and its tip is fused and connected to the quartz block 25 housed in the block housing 24.

As shown in FIG. 6, in the core wire fixing member 30, the uneven surface 31a of the inner wall of the portion where the slit 32 is provided is positioned on the optical fiber core wire 10 where the overcoat layer 40 is provided. Then, they move in the optical connector 20 toward the tip side and are internally fitted in the core wire fixing member accommodating portion 23. The core wire fixing member 30 is internally fitted into the core wire fixing member accommodating portion 23 in this way to close and crimp the gap of the slit 32, and the uneven surface 31a bites into the overcoat layer 40 to grip the core wire fixing member 30. Thereby, the optical fiber core wire 10 is fixed to the optical connector 20. Further, this constitutes a structure in which an overcoat layer 40 covering the optical fiber core wire 10 is interposed between the optical fiber core wire 10 and the core wire fixing member 30.

In the optical connector structure C according to the first embodiment, the laser light from the light source is emitted from the optical connector 20 on the incident end side, and the reflected light from the irradiated object is emitted from the optical connector 20 on the emitted end side. , It also enters the clad 11b of the optical fiber 11 via the quartz block 25 and propagates as clad mode light. Most of this clad mode light is emitted to the outside of the optical fiber 11 by a mode stripper 13 provided on the outer peripheral surface of the optical fiber 11 of the fiber exposed portion 10a of the optical fiber core wire 10 and removed in the optical connector 20. Will be done.

The fiber accommodating portion 21 of the optical connector 20 forms a space surrounding the portion of the optical fiber 11 of the fiber exposed portion 10a where the mode stripper 13 is provided, but the removal light of the clad mode light emitted from the mode stripper 13 is , Propagate through the fiber accommodating portion 21, and the mode stripper 13 in the fiber accommodating portion 21 reaches the facing inner wall and is absorbed. From the viewpoint of increasing the absorption efficiency of the removed light, the inner wall of the fiber accommodating portion 21 is preferably formed into a rough surface by machining such as polishing or cutting, chemical etching, laser processing, or the like. The removed light absorbed by the optical connector 20 is converted into heat, a part of the light is cooled inside the optical connector 20, and the rest is converted into infrared rays and emitted to the outside of the optical connector 20.

On the other hand, the clad mode light propagated backward without being removed by the mode stripper 13 is emitted to the overcoat layer 40 from the interface of the overcoat layer 40 at the portion where the fiber exposed portion 10a covers the optical fiber 11. Will be removed.

In addition, the clad mode light is removed from the interface between the optical fiber 11 and the jacket 12 through the jacket at the portion where the overcoat layer 40 covers the jacket 12 of the jacket covering portion 10b. The removal light of the clad mode light is emitted to the overcoat layer 40 from the interface between the jacket 12 and the overcoat layer 40.

At this time, from the viewpoint of efficiently emitting the removed light from the jacket 12 to the overcoat layer 40, the refractive index of the overcoat layer 40 is preferably the same as or higher than the refractive index of the jacket 12. Specifically, for example, when the jacket 12 is made of nylon resin (refractive index 1.53), the overcoat layer 40 is made of epoxy resin (refractive index 1.57), polycarbonate (refractive index 1.59), or the like. It may be formed with. When the jacket 12 is made of a fluororesin (refractive index 1.35), the overcoat layer 40 is formed of a fluororesin (refractive index 1.35), a silicone resin (refractive index 1.43), and polycarbonate. It may be formed of methyl methacrylate resin (refractive index 1.49), acrylic resin (refractive index 1.50), epoxy resin (refractive index 1.57), polycarbonate (refractive index 1.59), or the like.

On the other hand, the refractive index of the overcoat layer 40 may be lower than the refractive index of the jacket 12. Specifically, for example, when the jacket 12 is made of nylon resin (refractive index 1.53), the overcoat layer 40 is made of a fluororesin (refractive index 1.35) or a silicone resin (refractive index 1.43). ), Polymethyl methacrylate resin (refractive index 1.49), acrylic resin (refractive index 1.50) and the like. In this case, by confining and propagating the removal light of the clad mode light that has passed from the optical fiber 11 to the jacket 12 inside the jacket 12, the removal light can be gradually extinguished along the length direction of the jacket 12. .. Further, at this time, since the core wire fixing member 30 is not pushed into the jacket 12, the optical path of the clad mode light is not blocked in the jacket 12, thereby suppressing the rapid emission of the clad mode light. It is possible to suppress local heat generation near the core wire fixing portion.

The removal light of the clad mode light emitted to the overcoat layer 40 reaches the uneven surface 31a of the core wire fixing member 30 in contact with the overcoat layer 40. The removed light that reaches the uneven surface 31a of the core wire fixing member 30 is absorbed by the core wire fixing member 30 and converted into heat, which is conducted into the optical connector 20 through mechanical contact, and a part of the light is emitted. It is cooled inside the connector 20, and the rest is converted to infrared rays and emitted to the outside of the optical connector 20. From the viewpoint of enhancing the heat dissipation, the length L1 of the uneven surface 31a of the core wire fixing member 30 is preferably 3 mm or more and 100 mm or less, and more preferably 10 mm or more and 30 mm or less. The thickness T1 of the portion of the core wire fixing member 30 where the uneven surface 31a is provided is preferably 0.3 mm or more and 30 mm or less, and more preferably 1 mm or more and 10 mm or less. The overcoat layer 40 to which the removal light of the clad mode light is incident may generate heat, but from the viewpoint of improving the thermal conductivity and the heat dissipation to the core wire fixing member 30, the overcoat layer 40 For example, gold, aluminum, copper, metal powder of an alloy containing these metals, and thermally conductive ceramic powder such as silicon nitride and boron nitride may be dispersed and contained therein.

By the way, some of the removed light that has reached the uneven surface 31a of the core wire fixing member 30 is reflected on the uneven surface 31a without being absorbed by the core wire fixing member 30. Then, when the reflected light of the removed light returns to the optical fiber 11 again, it becomes clad mode light. However, since the uneven surface 31a of the core wire fixing member 30 has a structure in which grooves having a V-shaped cross section extending in the circumferential direction are continuously provided in the length direction, the effect of improving the gripping force on the overcoat layer 40 and the overcoating are achieved. In addition to the effect of improving heat dissipation by increasing the contact area with the layer 40, it is possible to obtain the effect of effectively suppressing the removal light from being reflected and returning to the optical fiber 11 because the removal light enters the groove. it can. The same effect can be obtained even when the groove shape of the uneven surface 31a is a trapezoidal shape, a U-shaped cross section, or a U-shaped cross section, but from the viewpoint of high effect, the V-shaped cross section and the cross-section table can be obtained. The shape is preferable. Further, since the uneven surface 31a comes into contact with the overcoat layer 40, the tip of the convex portion does not reach the jacket 12 and even the optical fiber 11, and therefore the groove depth D of the uneven surface 31a is set relatively deep. be able to. The groove depth D of the uneven surface 31a is preferably 0.05 mm or more and 5 mm or less, more preferably 0.3 mm or more and 1 mm or less, from the viewpoint of suppressing the reflection of the removed light and returning to the optical fiber 11. Further, from the same viewpoint, it is preferable that the surface of the uneven surface 31a is roughened.

In addition to this, according to the optical connector structure C according to the first embodiment, the overcoat layer 40 is interposed between the optical fiber core wire 10 and the core wire fixing member 30, and the thickness of the jacket 12 is increased. In addition, by adding the thickness of the overcoat layer 40, the optical path (cross-sectional area) of the clad mode light propagating in the jacket 12 is secured even in the vicinity of the core wire fixing portion, and the local emission of the clad mode light is suppressed. Will be done. Further, by adding the thickness of the overcoat layer 40 in addition to the thickness of the jacket 12, the clad mode light removed by the action of the overcoat layer 40 is reflected by the core wire fixing member 30, and the optical fiber 11 It is possible to suppress the return to the clad mode light again. As a result, local heat generation at the core wire fixing portion can be suppressed, and clad mode light can be safely and efficiently removed.

The thickness T2 of the overcoat layer 40 from the outer peripheral surface of the jacket 12 is preferably 0.5 times or more and 50 times or less the thickness of the jacket 12 from the viewpoint of suppressing the reflection of the removed light and returning to the optical fiber 11. , More preferably 1 time or more and 10 times or less. The length L2 of the overcoat layer 40 is preferably 1 mm or more and 100 mm or less, more preferably 5 mm or more and 15 mm or less, from the viewpoint of effectively obtaining the effect of suppressing the reflection of the removed light and returning to the optical fiber 11. The length L2 of the overcoat layer 40 is preferably the same as or longer than the length L1 of the uneven surface 31a of the core wire fixing member 30.

Inorganic materials such as silica, alumina, and sapphire, which are scatterers, may be dispersed and contained in the overcoat layer 40 from the viewpoint of preventing the removed light from being scattered and returning to the optical fiber 11.

Furthermore, according to the optical connector structure C according to the first embodiment, the outer diameter of the overcoat layer 40 can be freely set according to the inner diameter of the tip portion of the core wire fixing member 30, so that the optical fiber core can be freely set. It is not necessary to prepare a core wire fixing member 30 having an inner diameter that matches the outer diameter of the wire 10, or conversely, it is not necessary to prepare an optical fiber core wire 10 having an outer diameter that matches the inner diameter of the core wire fixing member 30. When the outer diameter of the optical fiber core wire 10 and the inner diameter of the core wire fixing member 30 do not match, excessive stress acts on the jacket 12 of the optical fiber core wire, or the core wire fixing member 30 of the optical fiber core wire 10 is subjected to excessive stress. It does not become insufficiently fixed. Further, by setting the outer diameter of the overcoat layer 40, the stress acting on the optical fiber core wire 10 from the core wire fixing member 30 can be adjusted, so that an excessive stress acts on the optical fiber core wire 10 and the laser is used. The propagation characteristics of the light are not impaired and therefore high quality laser light can be obtained.

(Embodiment 2)
FIG. 7 shows the optical connector structure C according to the second embodiment. The part having the same name as that of the first embodiment is indicated by the same reference numeral as that of the first embodiment.

In the optical connector structure C according to the second embodiment, the portion of the optical fiber core wire 10 covered with the overcoat layer 40 includes a portion where the jacket 12 is peeled off and the optical fiber 11 is exposed, and is formed on the outer peripheral surface of the portion. A mode stripper 14 is provided. According to the optical connector structure C according to the second embodiment, the clad mode light is efficiently emitted from the mode stripper 14 to the overcoat layer 40, so that the clad mode light can be removed more effectively. The mode stripper 14 is formed by, for example, machining the outer peripheral surface of the optical fiber 11 by machining such as polishing or cutting, chemical etching, laser processing, or depositing and melting fine particles such as silica. Consists of faces.

Other configurations and effects are the same as in the first embodiment.

(Embodiment 3)
FIG. 8 shows the optical connector structure C according to the third embodiment. The part having the same name as that of the first embodiment is indicated by the same reference numeral as that of the first embodiment.

In the optical connector structure C according to the third embodiment, the entire portion of the optical fiber core wire 10 covered with the overcoat layer 40 is included in the jacket-covered portion 10b covered with the jacket 12. According to the optical connector structure C according to the third embodiment, since the entire portion covered with the overcoat layer 40 is the jacket coating portion 10b, the overcoat layer 40 undergoes a dimensional change due to a temperature change or the like. However, since the jacket 12 is effectively elastically deformed and can absorb the deformation in any part, it is due to the presence of a structurally discontinuous surface (the interface between the coating tip of the jacket 12 and the overcoat layer 40) in the overcoat layer 40. It is possible to suppress the generation of local internal stress. Further, particularly in this structure, by setting the refractive index of the overcoat layer 40 to be lower than the refractive index of the jacket 12, the light for removing the clad mode light that has passed from the optical fiber 11 to the jacket 12 without leaking light to the outside. Can be confined inside the jacket 12, which is effective when the removal light is gradually extinguished in the length direction of the jacket 12.

Other configurations and effects are the same as in the first embodiment.

(Embodiment 4)
FIG. 9 shows the optical connector structure C according to the fourth embodiment. The part having the same name as that of the first embodiment is indicated by the same reference numeral as that of the first embodiment.

In the optical connector structure C according to the fourth embodiment, the overcoat layer 40 is provided with an inner coat layer 41 provided so as to contact and cover the optical fiber core wire 10, and an outer coat layer 42 provided on the outer side thereof. They are provided coaxially and are made of different materials. According to the optical connector structure C according to the fourth embodiment, for example, the outer coat layer 42 has a higher absorption performance and / or the scattering performance of the laser light than the inner coat layer 41. If the material of the above is selected, the removal light of the clad mode light emitted and removed by the overcoat layer 40 can be absorbed and scattered by the outer coat layer 42 to make it difficult to return to the optical fiber 11. Further, if those materials are selected so that the refractive index of the outer coat layer 42 is relatively higher than that of the inner coat layer 41, the light guiding from the inner coat layer 41 to the outer coat layer 42 becomes easier. In addition, it is possible to make it difficult to return to the optical fiber 11 from the outer coat layer 42. The absorption performance and scattering performance of the material forming the overcoat layer 40 can generally be measured by a spectrophotometer or a scattering coefficient measuring device using various light sources such as a laser.

The overcoat layer 40 of the optical connector structure C according to the fourth embodiment is, for example, as shown in FIG. 10A, an optical fiber core wire is formed in a first mold 61 in which a cavity 61a in the shape of an inner coat layer 41 is formed. The boundary portion between the exposed fiber portion 10a and the jacket covering portion 10b in No. 10 is set, and as shown in FIG. 10B, the resin material 41'forming the inner coat layer 41 is injected into the cavity 61a and cured, and then the drawing is shown. As shown in 10C, the optical fiber core wire 10 on which the inner coat layer 41 is formed is set in the second mold 62 in which the cavity 62a in the shape of the overcoat layer 40 is formed, and as shown in FIG. 10D, the optical fiber core wire 10 is set. It can be formed by injecting the resin material 42'that forms the outer coat layer 42 into the cavity 62a and curing it. Further, the overcoat layer 40 can also be formed by sequentially applying a resin on the jacket 12 and hardening the jacket 12 without using the dies 61 and 62.

Note that FIG. 9 shows a configuration in which the inner coat layer 41 covers both the fiber exposed portion 10a and the jacket covering portion 10b, but the present invention is not particularly limited, and the inner coat layer 41 is the fiber exposed portion. The outer coat layer 42 may cover only the fiber exposed portion 10a and the jacket covering portion 10b. Further, in addition to the configuration of the fourth embodiment, the configuration of the second embodiment or the third embodiment may be provided.

Other configurations and effects are the same as in the first embodiment.

(Embodiment 5)
FIG. 11 shows the optical connector structure C according to the fifth embodiment. The part having the same name as that of the first embodiment is shown by using the same reference numeral as that of the first embodiment.

In the optical connector structure C according to the fifth embodiment, the overcoat layer 40 constitutes a front end side coat layer 43 provided so as to form a front end side portion divided into two in the front and rear, and a rear side portion behind the front end side coat layer 43. It has a rear side coat layer 44 provided in the above, and they are made of different materials. Normally, the power of the removal light of the clad mode light is relatively higher on the front end side than on the rear side, but according to the optical connector structure C according to the fifth embodiment, for example, the absorption performance of the laser light. And / or if those materials are selected so that the scattering performance of the rear coat layer 44 is higher than that of the front coat layer 43, the tip having a high power of the removed light is opposite to the power distribution of the removed light. The side coat layer 43 absorbs / scatters the removed light less, while the rear side coat layer 44, which has a low power of the removed light, absorbs / scatters the removed light more, thereby averaging the absorption / scattering of the removed light. It is possible to suppress local heat generation that is biased toward the tip side. Further, by selecting the material so that the refractive index of the rear side coat layer 44 is higher than that of the front end side coat layer 43, it is possible to suppress the emission of the removed light biased to the tip side, and the same effect is obtained. Can be obtained.

The overcoat layer 40 of the optical connector structure C according to the fifth embodiment can be formed by separately molding the front side coat layer 43 and the rear side coat layer 44 as in the case of the fourth embodiment.

In FIG. 11, the boundary between the front end side coat layer 43 and the rear side coat layer 44 is provided at a position corresponding to the jacket covering portion 10b, but the present invention is not particularly limited to this, and the front end side coat is not particularly limited. The boundary between the layer 43 and the rear side coat layer 44 may be provided at a position corresponding to the fiber exposed portion 10a, and the boundary between the front end side coat layer 43 and the rear side coat layer 44 may be the fiber exposed portion. The configuration may be such that the boundary between the 10a and the jacket covering portion 10b is matched. Further, in addition to the configuration of the fifth embodiment, the configuration of the second embodiment or the third embodiment may be provided.

Other configurations and effects are the same as in the first embodiment.

(Embodiment 6)
FIG. 12 shows the optical connector structure C according to the sixth embodiment. The parts having the same names as those of the first and fifth embodiments are indicated by the same reference numerals as those of the first and fifth embodiments.

In the optical connector structure C according to the sixth embodiment, the overcoat layer 40 constitutes the front end side coat layer 43 provided so as to form the front end side portion divided into three in the front and rear, and the rear side portion behind the tip side coat layer 43. It has a rear coat layer 44 provided in the above and an intermediate coat layer 45 provided so as to form an intermediate portion between them, and they are formed of different materials. As in the case of the fifth embodiment, according to the optical connector structure C according to the sixth embodiment, for example, the absorption performance and / or the scattering performance of the laser light is higher than that of the front end side coat layer 43 in the rear side coat layer 44. If these materials are selected so that the intermediate coat layer 45 is between the front end side coat layer 43 and the rear side coat layer 44, the removal light is absorbed, contrary to the power distribution of the removal light. Scattering increases in the order of the tip side coat layer 43, the intermediate coat layer 45, and the rear side coat layer 44, thereby averaging the absorption and scattering of the removed light and suppressing the local heat generation biased to the tip side. Can be done. Further, those materials are selected so that the refractive index of the rear side coat layer 44 is higher than that of the front end side coat layer 43 and the intermediate coat layer 45 is between the front end side coat layer 43 and the rear side coat layer 44. However, the same effect can be obtained.

The overcoat layer 40 of the optical connector structure C according to the sixth embodiment is formed by separately molding the front side coat layer 43, the rear side coat layer 44, and the intermediate coat layer 45 as in the case of the fourth embodiment. be able to.

In FIG. 12, the boundary between the tip side coat layer 43 and the intermediate coat layer 45 is provided at a position corresponding to the fiber exposed portion 10a, but the present invention is not particularly limited to this, and the tip side coat layer is not particularly limited. The boundary between the 43 and the intermediate coat layer 45 may be provided at a position corresponding to the jacket covering portion 10b, and the boundary between the tip side coat layer 43 and the intermediate coat layer 45 may be provided between the fiber exposed portion 10a and the jacket. The configuration may be matched to the boundary with the covering portion 10b. In FIG. 12, the boundary between the intermediate coat layer 45 and the rear side coat layer 44 is provided at a position corresponding to the jacket covering portion 10b, but the present invention is not particularly limited to this, and the intermediate coat layer 45 and the rear side are not particularly limited to this. The boundary with the side coat layer 44 may be provided at a position corresponding to the fiber exposed portion 10a, and the boundary between the intermediate coat layer 45 and the rear side coat layer 44 may be provided between the fiber exposed portion 10a and the jacket covering portion. The configuration may be matched to the boundary with 10b. Further, in addition to the configuration of the sixth embodiment, the configuration of the second embodiment or the third embodiment may be provided.

Other configurations and effects are the same as in the first embodiment.

The present invention is useful in the technical field of optical connector structures.

C, C'Optical fiber core wire 10, 10'Optical fiber core wire 10a Fiber exposed part 10b Jacket covering part 11, 11' Optical fiber 11a, 11a' Core 11b, 11b' Clad 12, 12' Jacket 13, 14 Mode stripper 20 , 20'Optical connector 21 Fiber accommodation part 22 Sealing member 23 Core wire fixing member Storage part 24 Block housing part 25 Quartz block 30 Core wire fixing member 31 Core wire insertion hole 31a Concavo-convex surface 32 Slip 40 Overcoat layer 40', 41', 42' Resin material 41 Inner coat layer 42 Outer coat layer 43 Tip side coat layer 44 Rear side coat layer 45 Intermediate coat layer 51, 61, 62 Molds 51a, 61a, 62a Cavities

Claims (8)

An optical fiber core wire having an optical fiber containing a core and a clad and a jacket covering the optical fiber,
A tubular optical connector provided at the end of the optical fiber core wire,
A tubular core wire fixing member for fixing the optical fiber core wire to the optical connector by inserting the optical fiber core wire into the optical connector and caulking the optical fiber core wire.
It is an optical connector structure equipped with
In the optical connector, the optical fiber core wire has a fiber exposed portion on the distal end side where the jacket is peeled off and the optical fiber is exposed, and a jacket covering portion covered with the jacket continuous with the fiber exposed portion. And are composed of
An optical connector in which an overcoat layer covering the optical fiber core wire including a boundary portion between the fiber exposed portion and the jacket covering portion is interposed between the optical fiber core wire and the core wire fixing member. Construction. An optical fiber core wire having an optical fiber containing a core and a clad and a jacket covering the optical fiber,
A tubular optical connector provided at the end of the optical fiber core wire,
A tubular core wire fixing member for fixing the optical fiber core wire to the optical connector by inserting the optical fiber core wire into the optical connector and caulking the optical fiber core wire.
It is an optical connector structure equipped with
In the optical connector, the optical fiber core wire has a fiber exposed portion on the distal end side where the jacket is peeled off and the optical fiber is exposed, and a jacket covering portion covered with the jacket continuous with the fiber exposed portion. And are composed of
An optical connector structure in which an overcoat layer including the fiber exposed portion and the jacket covering portion and covering the optical fiber core wire is interposed between the optical fiber core wire and the core wire fixing member. An optical fiber core wire having an optical fiber containing a core and a clad and a jacket covering the optical fiber,
A tubular optical connector provided at the end of the optical fiber core wire,
A tubular core wire fixing member for fixing the optical fiber core wire to the optical connector by inserting the optical fiber core wire into the optical connector and caulking the optical fiber core wire.
It is an optical connector structure equipped with
In the optical connector, the optical fiber core wire has a fiber exposed portion on the distal end side where the jacket is peeled off and the optical fiber is exposed, and a jacket covering portion covered with the jacket continuous with the fiber exposed portion. And are composed of
An optical connector structure in which an overcoat layer covering a part of the tip of the jacket covering portion of the optical fiber core wire is interposed between the optical fiber core wire and the core wire fixing member. In the optical connector structure according to claim 3,
An optical connector structure in which the entire portion of the optical fiber core wire covered with the overcoat layer is the jacket-coated portion. In the optical connector structure according to any one of claims 1 to 4.
An optical connector structure in which a mode stripper is provided on the outer peripheral surface of the exposed fiber portion. In the optical connector structure according to any one of claims 1 to 5,
An optical connector structure in which the overcoat layer has an inner coat layer and an outer coat layer provided outside the inner coat layer and having a light absorption performance, a scattering performance, or a refractive index higher than that of the inner coat layer. In the optical connector structure according to any one of claims 1 to 5,
Light having the tip side coat layer and a rear side coat layer provided behind the tip side coat layer and having higher light absorption performance, scattering performance, or refractive index than the tip side coat layer. Connector structure. In the optical connector structure according to claim 7,
The overcoat layer is provided between the front end side coat layer and the rear side coat layer, and the light absorption performance, the scattering performance, or the refractive index is an intermediate coat between the front end side coat layer and the rear side coat layer. Optical connector structure with additional layers.

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