JP2010286734A - Composite optical waveguide - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a composite optical waveguide that reliably transmits light by securely bonding the ends of the cores of an optical waveguide and the ends of optical fibers. <P>SOLUTION: The composite optical waveguide includes: an optical waveguide 2 that has cores 41a to 41f; and an optical fiber bundle 5 that has optical fibers 6a to 6f. The end faces 411 of the cores 41a, 41b, 41c, 41d, 41e, and 41f face the end faces 61 of the optical fibers 6a, 6b, 6c, 6d, 6e, and 6f, respectively. A sealing member 8 seals the end faces facing each other. Thus, the optical waveguide 2 and the optical fiber bundle 5 are bonded to transmit light between the optical waveguide 2 and optical fiber bundle 5. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an optical waveguide assembly in which an optical waveguide and an optical fiber are bonded.

  In recent years, optical communications that transport data using optical frequency carriers have become increasingly important. In such optical communication, there is a joined body in which an optical waveguide and an optical fiber are joined as a means for guiding signal propagation light from one point to another point (for example, see Patent Document 1).

  The joined body described in Patent Document 1 includes a substrate, an optical waveguide integrally formed on the substrate, and an optical fiber inserted into a groove formed on the substrate. And the optical fiber is being fixed with respect to the board | substrate with the adhesive agent in the state inserted in the groove | channel of the board | substrate.

  By the way, in the joined body described in Patent Document 1, the end face of the optical waveguide and the end face of the optical fiber are separated from each other with a minute gap, that is, face each other with a minute gap. For this reason, for example, when dust or dirt enters into the gap, these cause a hindrance to the transmission of light, and as a result, there is a problem that it becomes impossible to transmit light between the optical waveguide and the optical fiber. . For example, when an unintentional force acts near the end face of the optical fiber, the end face of the optical fiber is deformed, and light passing through the optical fiber is scattered (diffused) by the deformed end face, so that a sufficient amount of light is obtained. Light cannot be transmitted to the optical waveguide, that is, light transmission is insufficient between the optical waveguide and the optical fiber.

JP-A-10-282362

  An object of the present invention is to provide an optical waveguide joined body in which light can be reliably transmitted by reliably joining an end face of a core portion of an optical waveguide and an end face of an optical fiber.

Such an object is achieved by the present inventions (1) to (13) below.
(1) an optical waveguide having at least one core portion;
At least one optical fiber;
The end face of the core part and the end face of the optical fiber face each other, and the periphery of the faced part is sealed with a sealing material, thereby joining the optical waveguide and the optical fiber, An optical waveguide assembly characterized in that light can be transmitted between the optical waveguide and the optical fiber.

(2) In the facing part, a gap is partially formed between the end face of the core part and the end face of the optical fiber,
The optical waveguide assembly according to (1), wherein a part of the sealing material enters the gap.

  (3) The optical waveguide joined body according to (2), wherein the sealing material has a higher refractive index in a portion that enters the gap than a refractive index in other portions.

  (4) The joined optical waveguide according to (2) or (3), wherein a gap distance of the gap is 10 μm or less.

  (5) The optical waveguide assembly according to any one of (1) to (4), wherein a refractive index of the sealing material is a value between a refractive index of the optical fiber and a refractive index of the core portion.

  (6) The optical waveguide assembly according to any one of (1) to (5), wherein the sealing material is made of a resin material having photocurability or thermosetting.

  (7) The optical waveguide joined body according to any one of (1) to (6), wherein the optical fiber has a core portion made of a material different from a constituent material of the core portion of the optical waveguide.

  (8) When the areas of the end face of the core portion of the optical waveguide and the end face of the core portion of the optical fiber are compared, the area of the end face on the light incident side is larger than the area of the end face on the output side (7) The optical waveguide assembly according to (7).

  (9) The optical waveguide according to (7) or (8), wherein one end surface includes the other end surface of the end surface of the core portion of the optical waveguide and the end surface of the core portion of the optical fiber. Joined body.

(10) The optical waveguide is provided with a plurality of the core portions,
A plurality of the optical fibers are installed,
10. The optical waveguide joined body according to any one of (1) to (9), wherein one optical fiber is joined to each core part.

(11) A plurality of the optical fibers are installed,
The optical waveguide joined body according to any one of the above (1) to (10), wherein a plurality of the optical fibers are joined to one core part.

(12) The optical waveguide is provided with a plurality of the core portions,
The optical waveguide joined body according to any one of (1) to (10), wherein a plurality of the core portions are joined to one optical fiber.

(13) A plurality of the optical fibers are installed,
The optical waveguide joined body according to any one of (1) to (12), further including a holding member that bundles and holds the plurality of optical fibers.

  According to the present invention, the positional relationship between the core portion of the optical waveguide and the optical fiber is restricted by the sealing material, and the position restricted state is maintained. As a result, the end face of the core portion of the optical waveguide and the end face of the optical fiber are securely joined, and thus, from the optical waveguide to the optical fiber or in the opposite direction, that is, between the optical waveguide and the optical fiber. Light can be transmitted reliably.

  Further, in the contact portion, when a gap is partly formed between the end face of the core portion of the optical waveguide and the end face of the optical fiber, and a part of the sealing material enters the gap, the sealing is performed. The end face of the core portion of the optical waveguide and the end face of the optical fiber are more reliably bonded via the material. Thereby, light can be more reliably transmitted from the optical waveguide to the optical fiber or in the opposite direction.

It is a longitudinal section showing a 1st embodiment of an optical waveguide zygote of the present invention. FIG. 2 is an enlarged detail view of a region [A] surrounded by a one-dot chain line in FIG. 1. FIG. 2 is an exploded perspective view of the joined optical waveguide shown in FIG. 1. It is a longitudinal cross-sectional view which shows 2nd Embodiment of the optical waveguide joined body of this invention. It is a disassembled perspective view which shows 3rd Embodiment of the optical waveguide joined body of this invention. It is a longitudinal cross-sectional view which shows 4th Embodiment of the optical waveguide joined body of this invention. It is a disassembled perspective view which shows 5th Embodiment of the optical waveguide conjugate | zygote of this invention. It is a disassembled perspective view which shows 6th Embodiment of the optical waveguide conjugate | zygote of this invention. It is a disassembled perspective view which shows 7th Embodiment of the optical waveguide joined body of this invention. It is an enlarged longitudinal cross-sectional view which shows the contact part vicinity of the optical-waveguide assembly (8th Embodiment) of this invention. It is a figure which shows the manufacturing method of the optical waveguide conjugate | zygote shown in FIG. 10 in order. It is a figure which shows the manufacturing method of the optical waveguide conjugate | zygote shown in FIG. 10 in order. It is a figure which shows the manufacturing method of the optical waveguide conjugate | zygote shown in FIG. 10 in order. It is a figure which shows the manufacturing method of the optical waveguide conjugate | zygote shown in FIG. 10 in order. It is a figure which shows the manufacturing method of the optical waveguide conjugate | zygote shown in FIG. 10 in order. It is a figure which shows the manufacturing method of the optical waveguide conjugate | zygote shown in FIG. 10 in order.

  The optical waveguide assembly of the present invention will be described below in detail based on preferred embodiments shown in the accompanying drawings.

<First Embodiment>
FIG. 1 is a longitudinal sectional view showing a first embodiment of an optical waveguide assembly of the present invention, FIG. 2 is an enlarged detailed view of a region [A] surrounded by an alternate long and short dash line in FIG. 1, and FIG. FIG. 2 is an exploded perspective view of the optical waveguide assembly shown in FIG. Hereinafter, for convenience of explanation, the right side in FIGS. 1 to 3 (the same applies to FIGS. 4 to 10) is referred to as “right”, and the left side is referred to as “left”.

  An optical waveguide assembly 1 shown in FIG. 1 includes a strip-shaped optical waveguide 2 and a strip-shaped optical fiber bundle 5, and these end faces are bonded to each other. The optical waveguide assembly 1 can transmit light L from the optical fiber bundle 5 to the optical waveguide 2. Hereinafter, the configuration of each unit will be described.

  The optical waveguide 2 is formed by laminating a cladding layer (first cladding layer (cladding portion)) 3a, a core layer 4, and a cladding layer (second cladding layer (cladding portion)) 3b in this order from the lower side in FIG. It will be.

  The core layer 4 includes core portions (waveguide channels) 41a, 41b, 41c, 41d, 41e, and 41f that are linear in a plan view, and side cladding portions (clad portions) 42a and 42b that are linear in a plan view. , 42c, 42d, 42e, 42f, and 42g are formed and are alternately arranged. Thus, the optical waveguide 2 is a multi-channel one having a plurality of core portions.

  Since the configuration of each of the core portions 41a to 41f is substantially the same, the core portion 41a will be representatively described below. Further, since the configurations of the side clad portions 42a to 42g are substantially the same, the side clad portion 42a will be representatively described below.

  The core portion 41a and the side clad portion 42a each have a square shape such as a square or a rectangle (rectangle). The width and height of the core portion 41a and the side clad portion 42a are not particularly limited, but are preferably about 1 to 200 μm, more preferably about 5 to 100 μm, and about 10 to 60 μm. Is more preferable.

  The optical waveguide 2 totally reflects light incident on the core portion 41a from the right side at the interface between the core portion 41a and the clad portions (the side clad portions 42a and 42b and the clad layers 3a and 3b) and propagates the light to the left side. be able to.

  The core portion 41a and the side cladding portion 42a have different light refractive indexes, and the difference in refractive index is not particularly limited, but is preferably 0.5% or more, and is 0.8% or more. Is more preferable. On the other hand, the upper limit value may not be set, but is preferably about 5.5%. If the difference in refractive index is less than the lower limit, the effect of transmitting light may be reduced, and even if the upper limit is exceeded, no further increase in light transmission efficiency can be expected.

The refractive index difference is expressed by the following equation, where A is the refractive index of the core portion 41a and B is the refractive index of the side cladding portion 42a.
Refractive index difference (%) = | A / B-1 | × 100

  The core portion 41a is made of a material having a higher refractive index than that of the side clad portion 42a, and is also made of a material having a higher refractive index than the cladding layers 3a and 3b.

  The constituent materials of the core portion 41a, the side clad portion 42a, and the clad layers 3a and 3b are not particularly limited as long as the above-described refractive index difference is generated, but in this embodiment, the core portion 41a and the side clad portion 42a. Are made of the same material, and the refractive index difference between the core portion 41a and the side cladding portion 42a is expressed by the difference in the chemical structure of each material.

  Any material can be used as the constituent material of the core layer 4 as long as the material is substantially transparent to the light propagating through the core portion 41a. Specifically, acrylic resin, methacrylic resin can be used. In addition to various resin materials such as polycarbonate, polystyrene, epoxy resin, polyamide, polyimide, polybenzoxazole, polysilane, polysilazane, and cyclic olefin resins such as benzocyclobutene resin and norbornene resin, quartz glass, borosilicate A glass material such as acid glass can be used.

  Among these, in order to express a difference in refractive index due to a difference in chemical structure as in the present embodiment, the refractive index changes by irradiation with active energy rays such as ultraviolet rays and electron beams (or by further heating). Preferably it is a material.

  As such a material, for example, the chemical structure changes due to, for example, at least part of the bond being cut or bound or at least part of the functional group being desorbed and modified by irradiation with active energy rays or heating. Possible materials are listed.

  Specifically, silane-based resins such as polysilane (eg, polymethylphenylsilane), polysilazane (eg, perhydropolysilazane), and the resin serving as a base for materials with structural changes as described above include molecules on the molecular side. The following resins (1) to (6) having a functional group at the chain or terminal may be mentioned. (1) Addition (co) polymer of norbornene type monomer obtained by addition (co) polymerization of norbornene type monomer, (2) Addition copolymer of norbornene type monomer and ethylene or α-olefins, (3) An addition copolymer of a norbornene-type monomer and a non-conjugated diene and, if necessary, another monomer, (4) a ring-opening (co) polymer of a norbornene-type monomer, and, if necessary, the (co) polymer A hydrogenated resin, (5) a ring-opening copolymer of a norbornene monomer and ethylene or α-olefins, and a resin in which the (co) polymer is hydrogenated, if necessary, (6) a norbornene monomer Ring-opening copolymers with non-conjugated dienes or other monomers, and norbornene-based resins such as resins obtained by hydrogenating the (co) polymers if necessary, and other photo-curing reactive monomers An acrylic resin or an epoxy resin obtained by polymerizing a polymer.

  Of these, norbornene resins are particularly preferred. These norbornene-based polymers include, for example, ring-opening metathesis polymerization (ROMP), combination of ROMP and hydrogenation reaction, polymerization by radical or cation, polymerization using a cationic palladium polymerization initiator, and other polymerization initiators ( For example, it can be obtained by any known polymerization method such as polymerization using a polymerization initiator of nickel or another transition metal).

  Cladding layers 3a and 3b are disposed on both surfaces of the core layer 4, respectively. The clad layers 3 a and 3 b constitute clad portions located at the lower and upper portions of the core layer 4, respectively, and are in contact with the core layer 4. With such a configuration, each of the core portions 41a to 41f functions as a light guide path whose outer periphery is surrounded by the clad portion.

  Since the clad layers 3a and 3b have substantially the same configuration, the clad layer 3a will be described below representatively.

  The thickness of the clad layer 3a is preferably about 0.05 to 1.5 times the thickness of the core layer 4, more preferably about 0.1 to 1.25 times, specifically, The thickness is not particularly limited, but it is usually preferably about 1 to 200 μm, more preferably about 2 to 100 μm, and still more preferably about 10 to 60 μm. Thereby, the function as a clad layer is suitably exhibited while preventing the optical waveguide 2 from being unnecessarily enlarged (thickened). The thickness of the clad layer 3a and the thickness of the clad layer 3b are the same in the illustrated configuration, but are not limited thereto and may be different.

  Further, as the constituent material of the clad layer 3a, for example, the same material as the constituent material of the core layer 4 described above can be used, but a norbornene-based polymer is particularly preferable.

  In the present embodiment, it is possible to select and use different materials appropriately between the constituent material of the core layer 4 and the constituent material of the cladding layer 3a in consideration of the refractive index difference between the two. is there. Therefore, in order to ensure total reflection of light at the boundary between the core layer 4 and the clad layer 3a, a material may be selected so that a sufficient difference in refractive index is generated. Thereby, a sufficient refractive index difference is obtained in the thickness direction of the optical waveguide 2, and light can be prevented from leaking from the core portions 41a to 41f to the cladding layers 3a and 3b. As a result, attenuation of light propagating through the core parts 41a to 41f can be suppressed.

  From the viewpoint of suppressing light attenuation, it is preferable that the adhesion between the core layer 4 and the cladding layer 3a is high. Therefore, the constituent material of the cladding layer 3a may be any material as long as it satisfies the condition that the refractive index is lower than that of the constituent material of the core layer 4 and the adhesiveness to the constituent material of the core layer 4 is high. Good.

  For example, the norbornene-based polymer having a relatively low refractive index is preferably one containing a norbornene repeating unit having a substituent containing an epoxy structure at the terminal. Such a norbornene-based polymer has a particularly low refractive index and good adhesion.

  Further, the norbornene-based polymer preferably contains an alkylnorbornene repeating unit. Since the norbornene-based polymer containing the alkylnorbornene repeating unit has high flexibility, high flexibility (flexibility) can be imparted to the optical waveguide 2 by using such norbornene-based polymer.

  Examples of the alkyl group that the alkylnorbornene repeating unit has include a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a nonyl group, and a decyl group, and a hexyl group is particularly preferable. These alkyl groups may be either linear or branched.

  By including the repeating unit of hexyl norbornene, it is possible to prevent the refractive index of the entire norbornene-based polymer from increasing. A norbornene-based polymer having a repeating unit of hexyl norbornene is preferable because it has excellent transmittance with respect to light in the wavelength region as described above (particularly in the wavelength region near 850 nm).

  The constituent materials of the clad layers 3a and 3b and the side clad portions 42a to 42g may be the same (same type) or different materials, but these preferably have approximate refractive indexes. .

  Such an optical waveguide 2 is slightly different depending on the optical characteristics of the materials of the core portions 41a to 41f and is not particularly limited. For example, the optical waveguide 2 is preferably used in data communication using light L in a wavelength region of about 600 to 1550 nm. Is done.

  The optical fiber bundle 5 includes linear optical fibers 6a, 6b, 6c, 6d, 6e, 6f arranged in a row, and a holding member 7 that bundles and holds these optical fibers 6a to 6f. It consists of As shown in FIGS. 1 and 3, in the optical waveguide assembly 1, the end surface 411 of the core portion 41a and the end surface 61 of the optical fiber 6a face each other at a very short distance (surface contact), and similarly, the core The end face 411 of the part 41b and the end face 61 of the optical fiber 6b face each other, the end face 411 of the core part 41c and the end face 61 of the optical fiber 6c face each other, and the end face 411 of the core part 41d and the end face 61 of the optical fiber 6d face each other. The end face 411 of the core part 41e and the end face 61 of the optical fiber 6e face each other, and the end face 411 of the core part 41f and the end face 61 of the optical fiber 6f face each other. That is, in the optical waveguide assembly 1, the core portion and the optical fiber are in a 1: 1 correspondence. Thereby, all the core parts 41a-41f and the optical fibers 6a-6f which the optical waveguide assembly 1 has can be used. Further, since the core portion and the optical fiber shown in FIG. 3 correspond to each other in a 1: 1 ratio, leakage of the signal light at the coupling portion, attenuation of the signal light intensity associated therewith, and leaked light is transmitted to other core portions and light. There is also an advantage that noise generation and signal quality deterioration due to mixing (stray light) in the fiber can be avoided.

  Since the configurations of the optical fibers 6a to 6f are substantially the same, the optical fiber 6a will be described below representatively.

  The optical fiber 6a has a core part 60 serving as a core and a clad part (not shown) covering the outer periphery thereof, and the end surface 61 of the core part 60 has a shape (cross-sectional shape) as shown in FIG. It is a circle. And the magnitude | size of the end surface 411 (area) of the core part 41a is larger than the magnitude | size (area) of the end surface 61 of this optical fiber 6a (core part 60). That is, the end surface 411 of the core part 41a includes the end surface 61 of the optical fiber 6a (core part 60). Thereby, when the light L that has passed through the optical fiber 6a is emitted from the end face 61 and enters the end face 411 having a size larger than that of the end face 61, all of the light L can surely enter the end face 411. it can. Further, for example, even when the central axis of the optical fiber 6a and the central axis of the core portion 41a are slightly shifted, the entire end surface 61 of the optical fiber 6a and the entire end surface 411 of the core portion 41a are reliably opposed to each other. To do. Thereby, the light L that has passed through the optical fiber 6a can surely enter the core portion 41a.

  In addition, as a constituent material of the core part 60, materials different from the core layer 4 (core part 41a), for example, inorganic materials, such as a silica glass and quartz glass, are mentioned. Further, the constituent material of the cladding part covering the outer periphery of the core part 60 is not particularly limited as long as it is a material having a refractive index lower than that of the core part. For example, in addition to silica glass and quartz glass, germanium oxide as necessary In addition to inorganic materials such as silica glass doped with various additives such as fluorine, fluorine compounds, etc., organic materials such as silicone, organic-inorganic hybrid silicone materials, and various fluorine-based polymers can be used.

  The holding member 7 is provided in the middle of the optical fibers 6a to 6f, and holds the portion collectively. The holding member 7 regulates the positional relationship between the optical fibers 6a to 6f. Therefore, when joining the optical fibers 6a to 6f and the core portions 41a to 41f of the optical waveguide 2, the joining work can be easily performed. it can.

  As shown in FIG. 3, the holding member 7 has a band plate shape. The optical fibers 6 a to 6 f are arranged along the width direction of the holding member 7, and the middle of each of the optical fibers 6 a to 6 f is embedded (covered) in the holding member 7. Since each of the optical fibers 6 a to 6 f is embedded in the holding member 7 in this way, the left end (near the end surface 61) is exposed from the holding member 7.

  The constituent material of the holding member 7 is not particularly limited. For example, natural rubber, isoprene rubber, butadiene rubber, styrene-butadiene rubber, nitrile rubber, chloroprene rubber, butyl rubber, acrylic rubber, ethylene-propylene rubber, hydrin rubber, Various rubber materials (especially those vulcanized) such as urethane rubber, silicone rubber, fluoro rubber, styrene, polyolefin, polyvinyl chloride, polyurethane, polyester, polyamide, polybutadiene, trans polyisoprene Various thermoplastic elastomers such as those based on fluorocarbons, fluororubbers, and chlorinated polyethylenes can be used, and one or more of these can be used in combination.

  As shown in FIG. 2, in the contact portion 11 between the end surface 411 of the core portion 41 a of the optical waveguide 2 and the end surface 61 of the optical fiber 6 a, a gap 111 is partially formed between these end surfaces 411 and 61. . A part of the sealing material 8 described later enters the gap 111.

  Note that the gap distance d of the gap 111 is not particularly limited, and is preferably 10 μm or less, for example, and more preferably 0.01 to 2 μm. If the gap distance d is less than the lower limit value, voids are likely to remain in the gap 111, which may cause irregular reflection at the joint surface (end surface 411, end surface 61). In addition to light leakage at 111, management of the gap distance d during manufacture becomes difficult.

  The gap 111 may also be formed in another contact portion 11 (for example, between the end surface 411 of the core portion 41b and the end surface 61 of the optical fiber 6b) different from the contact portion 11 shown in FIG.

  As shown in FIGS. 1 and 2, in the optical waveguide assembly 1, each gap 111 and the vicinity thereof are sealed (covered) with a sealing material 8. That is, in the optical waveguide assembly 1, the sealing material 8 is provided across the right end portion of the optical waveguide 2 and the left end portion of the optical fiber bundle 5. As a result, the positional relationship (gap distance d) between the core portions 41a to 41f of the optical waveguide 2 and the optical fibers 6a to 6f is regulated, and the positional regulation state is maintained. Thereby, each core part 41a-41f and each optical fiber 6a-6f are reliably joined, Therefore Light L can be reliably transmitted to the optical waveguide 2 from the optical fiber bundle 5. FIG.

  The sealing material 8 is made of a resin material, and the material is an ultraviolet curable type, a visible light curable type, or an electron beam curable type such as a silicone type, an epoxy type, an acrylic type, a cyanoacrylate type, and a polyurethane type. A mold material can be suitably used. In addition, a thermosetting material can also be suitably used as long as it is a material with little volume change due to curing and volume change due to heat. Of these materials, ultraviolet curable and visible light curable materials having photocurability are particularly preferable. Thereby, the sealing material 8 can be easily applied to each gap 111 in a liquid state, and the applied sealing material 8 can be easily cured. That is, the optical waveguide assembly 1 can be easily manufactured.

  As shown in FIG. 2, a part of the sealing material 8 enters the gap 111. Thereby, in the contact part 11, the end surface 411 of the core part 41a of the optical waveguide 2 and the end surface 61 of the optical fiber 6a are more reliably joined via the sealing material 8. Thereby, the light L can be more reliably transmitted from the optical fiber bundle 5 to the optical waveguide 2.

  In addition, it is preferable that the refractive index of the sealing material 8 takes the intermediate value of the refractive index of optical fiber 6a-6f and the refractive index of core part 41a-41f. Thereby, compared with the case where air exists in the gap 111, the light emitted from the optical fibers 6a to 6f side is also emitted from the core portions 41a to 41f side when the light is incident on the core portions 41a to 41f. Even when light enters the optical fibers 6a to 6f, since the spread of the light emitted from the end face is suppressed, there is an advantage that the coupling loss at the contact portion 11 is improved (reduced).

Moreover, such an optical waveguide joined body 1 is manufactured as follows, for example.
First, the end surface 411 of each core part 41a-41f of the optical waveguide 2 and the end surface 61 of each optical fiber 6a-6f are mutually contacted.

  Next, in this state, a liquid sealing material 8 (ultraviolet curable type) is applied to each contact portion by, for example, a spray method. Thereby, each contact part is sealed with the liquid sealing material 8, respectively.

Next, the applied liquid sealing material 8 is irradiated with ultraviolet rays. Thereby, the sealing material 8 is hardened.
The optical waveguide assembly 1 can be manufactured by such a manufacturing method.

<Second Embodiment>
FIG. 4 is a longitudinal sectional view showing a second embodiment of the joined optical waveguide of the present invention.

  Hereinafter, a second embodiment of the optical waveguide joined body of the present invention will be described with reference to this figure. However, the description will focus on differences from the above-described embodiment, and the description of the same matters will be omitted.

  This embodiment is the same as the first embodiment except that the size relationship between the end face size of the core portion and the end face size of the optical fiber is different.

  In the optical waveguide assembly 1 </ b> A shown in FIG. 4, the size of the end surface 411 of each of the core portions 41 a to 41 f of the optical waveguide 2 is smaller than the size of the end surface 61 of each of the optical fibers 6 a to 6 f of the optical fiber bundle 5. The core portion 41a and the optical fiber 6a, the core portion 41b and the optical fiber 6b, the core portion 41c and the optical fiber 6c, the core portion 41d and the optical fiber 6d, the core portion 41e and the optical fiber 6e, and the core portion 41f and the light that are bonded to each other. In the fiber 6f, since the size relationship between the end faces 411 and 61 is the same, the core portion 41a and the optical fiber 6a will be described below representatively.

  Due to the magnitude relationship as described above, when the light L that has passed through the core portion 41 a is emitted from the end face 411 and is incident on the end face 61 that is larger in size than the end face 411, all of the light L is reliably transmitted to the end face 61. Can be incident. Further, for example, even when the central axis of the optical core portion 41a and the central axis of the fiber 6a are slightly shifted, the entire end surface 411 of the core portion 41a and the entire end surface 61 of the optical fiber 6a are reliably opposed to each other. To do. Thereby, the light L that has passed through the core portion 41a can surely enter the optical fiber 6a.

<Third Embodiment>
FIG. 5 is an exploded perspective view showing a third embodiment of the joined optical waveguide of the present invention.

  Hereinafter, the third embodiment of the optical waveguide joined body of the present invention will be described with reference to this figure. However, the description will focus on differences from the above-described embodiment, and the description of the same matters will be omitted.

  This embodiment is the same as the first embodiment except that the number of optical fibers bonded to one core part is different.

  In the optical waveguide assembly 1B shown in FIG. 5, the optical fiber bundle 5B includes six sets of optical fibers 6g, 6h, and 6i, each grouped by three. Each set of optical fibers 6g to 6i is joined to each core portion 41a to 41f of the optical waveguide 2, respectively. That is, in the optical waveguide assembly 1B, the core portion and the optical fiber correspond to each other at 1: 3. Since the optical fibers 6g to 6i in each group have the same configuration, the optical fibers 6g to 6i bonded to the core portion 41a will be representatively described below.

  In the optical fiber bundle 5B, the optical fibers 6g to 6i are arranged in a state where the outer peripheral surfaces are in contact with each other. Further, the end faces 61 of the optical fibers 6g to 6i are each smaller in size than the end face 411 of the core portion 41a. Further, the sum of the sizes of the three end surfaces 61 is also smaller than the size of the end surface 411 of the core portion 41a. That is, the three end surfaces 61 are collectively included in the end surface 411 of the core portion 41a.

  With such a configuration, for example, even when one of the optical fibers 6g to 6i cannot be used, light can be transmitted through the remaining other optical fibers. Further, when the signal propagation intensity is reduced due to the optical fiber breakage, the signal intensity on the exit side does not become zero, so there is also an advantage that the broken part can be estimated from the degree of the strength reduction. In addition, since different signal light and different wavelength light can be input for each optical fiber, there is an advantage that a device for multiplexing signals can be more easily manufactured.

<Fourth embodiment>
FIG. 6 is a longitudinal sectional view showing a fourth embodiment of the joined optical waveguide of the present invention.

  Hereinafter, a fourth embodiment of the optical waveguide joined body of the present invention will be described with reference to this figure. However, the difference from the above-described embodiment will be mainly described, and the description of the same matters will be omitted.

  The present embodiment is the same as the first embodiment except that the number of core portions bonded to one optical fiber is different.

  In the optical waveguide joined body 1C shown in FIG. 6, the three core portions 41a to 41c of the optical waveguide 2 are joined to one optical fiber 6j (the same applies to the core portions 41d to 41f). That is, in the optical waveguide assembly 1B, the core portion and the optical fiber correspond to each other at 3: 1.

  The end surfaces 411 of the core portions 41a to 41c are each smaller in size than the end surface 61 of the optical fiber 6j. Further, the sum of the sizes of the three end surfaces 411 is also smaller than the size of the end surface 61 of the optical fiber 6j. That is, the three end faces 411 are collectively included in the end face 61 of the optical fiber 6j.

  With such a configuration, for example, even when one of the core portions 41a to 41c cannot be used, light can be transmitted by the remaining other core portions.

<Fifth Embodiment>
FIG. 7 is an exploded perspective view showing a fifth embodiment of the joined optical waveguide of the present invention.

  Hereinafter, a fifth embodiment of the optical waveguide joined body of the present invention will be described with reference to this figure. However, the difference from the above-described embodiment will be mainly described, and description of similar matters will be omitted.

  This embodiment is the same as the fourth embodiment except that the number of core portions bonded to one optical fiber is different.

  An optical waveguide assembly 1D shown in FIG. 7 includes an optical waveguide 2D having two core portions 41a and 41b, and one optical fiber 6k. In the optical waveguide joined body 1D, the core portions 41a and 41b and the optical fiber 6k are joined. That is, in the optical waveguide assembly 1D, the core portion and the optical fiber correspond to each other at 2: 1.

  The end surfaces 411 of the core portions 41a and 41b are smaller in size than the end surface 61 of the optical fiber 6k. Further, the sum of the sizes of the two end faces 411 is also smaller than the size of the end face 61 of the optical fiber 6k. That is, the two end faces 411 are collectively included in the end face 61 of the optical fiber 6k.

  With such a configuration, for example, even when one of the core portions 41a and 41b cannot be used, light can be transmitted by the other core portion. Also, it can be used for signal multiplexing as described above, or for observation to monitor the return light from the surface when, for example, a photodiode is connected to the tip of the optical fiber. There is also an advantage that it can be used as an auxiliary optical path.

<Sixth Embodiment>
FIG. 8 is an exploded perspective view showing a sixth embodiment of the joined optical waveguide of the present invention.

  Hereinafter, the sixth embodiment of the optical waveguide joined body according to the present invention will be described with reference to this figure. However, the difference from the above-described embodiment will be mainly described, and the description of the same matters will be omitted.

  This embodiment is the same as the fourth embodiment except that the number of core portions bonded to one optical fiber is different.

  In the optical waveguide assembly 1E shown in FIG. 8, in the optical waveguide 2E, two core layers 4a and 4b are disposed between the cladding layer 3a and the cladding layer 3b.

  The core layer (first core layer) 4a and the core layer (second core layer) 4b are respectively formed with core portions 41g and 41h and side clad portions 42h, 42i and 42j, which are alternately arranged. It has been done. Further, a clad layer (third clad layer (clad portion)) 3c having the same configuration as that of the clad layers 3a and 3b is interposed between the core layer 4a and the core layer 4b.

  As described above, the optical waveguide 2E is a multi-channel optical waveguide having four core portions arranged in a “field” shape when viewed from one end side (in front view).

  In the optical waveguide assembly 1E, the core portions 41g and 41h of the core layer 4a and the core portions 41g and 41h of the core layer 4b are bonded to one optical fiber 6k. That is, in the optical waveguide assembly 1E, the core portion and the optical fiber correspond to each other at 4: 1.

  The end surfaces 411 of the core portions 41a and 41b are smaller in size than the end surface 61 of the optical fiber 6k. Further, the sum of the sizes of the end surfaces 411 of the core portions 41a and 41b of the core layer 4a and the end surfaces 411 of the core portions 41a and 41b of the core layer 4b is also smaller than the size of the end surface 61 of the optical fiber 6k. That is, the four end faces 411 are collectively included in the end face 61 of the optical fiber 6k.

<Seventh embodiment>
FIG. 9 is an exploded perspective view showing a seventh embodiment of the joined optical waveguide of the present invention.

Hereinafter, the seventh embodiment of the optical waveguide joined body of the present invention will be described with reference to this figure, but the description will focus on differences from the above-described embodiment, and the description of the same matters will be omitted.
This embodiment is the same as the sixth embodiment except that the number of optical fibers is different.

  In the optical waveguide assembly 1F shown in FIG. 9, the optical fiber bundle 5F has four optical fibers 6L, 6m, 6n, and 6p. Moreover, these optical fibers 6L-6p are arrange | positioned in the shape of a "field" when it is seen from one end side (in front view), ie, correspond to the core parts 41g and 41h of the optical waveguide 2E. Are arranged as follows. Thereby, the optical fiber 6L is bonded to the core portion 41g of the core layer 4a, the optical fiber 6m is bonded to the core portion 41h of the core layer 4a, and the optical fiber 6n is bonded to the core portion 41g of the core layer 4b. The optical fiber 6p is joined to the core portion 41h of the core layer 4b. That is, in the optical waveguide assembly 1E, the core portion and the optical fiber correspond to each other at 1: 1. In addition, the size of the end face 61 of each of the optical fibers 6L to 6p is larger than the size of the end face 411 of the core portions 41g and 41h, respectively.

<Eighth Embodiment>
FIG. 10 is an enlarged longitudinal sectional view showing the vicinity of the contact portion of the optical waveguide assembly (eighth embodiment) according to the present invention, and FIGS. 11 to 16 show the manufacturing method of the optical waveguide assembly shown in FIG. FIG. In the following, for convenience of explanation, the upper side in FIGS. 11 to 16 is referred to as “upper” or “upper”, and the lower side is referred to as “lower” or “lower”.

  Hereinafter, an optical waveguide joined body according to an eighth embodiment of the present invention will be described with reference to these drawings. However, differences from the above-described embodiment will be mainly described, and description of similar matters will be omitted.

  This embodiment is the same as the first embodiment except that the configuration of the contact portion (sealing material) is different.

  In the optical waveguide assembly 1G shown in FIG. 10, in the vicinity of each contact portion 11, a portion that enters the gap 111 of the sealing material 8 </ b> G (hereinafter referred to as “first portion 81”) and a first portion 81. Other portions (hereinafter referred to as “second portion 82”) have different refractive indexes. Specifically, the refractive index of the first portion 81 is higher than the refractive index of the second portion 82, and is an intermediate value between the refractive indexes of the core portion 41a and the optical fiber 6a. Yes. Thereby, since leakage of light from the first portion 81 is suppressed to some extent, when the light emitted from the optical fiber 6 a passes through the first portion 81, a part of the light is second portion 82. Is prevented from being scattered toward the surface, and thus reliably enters the core portion 41a.

  As the resin material constituting the first portion 81, the materials mentioned in the description of the sealing material 8 of the first embodiment can be used. In addition, the resin material constituting the second portion 82 is not particularly limited, and for example, there is no need to be cured depending on the application other than a photocurable adhesive or a thermosetting adhesive having a relatively low refractive index. Examples thereof include gel-like filling and silicon oil.

  Next, a method for manufacturing the optical waveguide assembly 1G will be described with reference to FIGS.

  First, the optical fiber bundle 5 is prepared. Then, as shown in FIG. 11, the vicinity of the end face 61 of each of the optical fibers 6a to 6f of the optical fiber bundle 5 is impregnated in a water tank containing a liquid resin material 811 constituting the first portion 81 (dipping). To do).

  Next, as shown in FIG. 12, the optical fiber bundle 5 is pulled up. Thereby, the liquid ball 812 of the resin material 811 is formed in the end surface 61 of each optical fiber 6a-6f, respectively.

  Next, the optical waveguide 2 is prepared. And as shown in FIG. 13, the liquid ball 812 formed in the end surface 61 of each optical fiber 6a-6f is made to contact each core part 41a-41f of the optical waveguide 2, respectively.

  Next, as shown in FIG. 14, the gap distance d is adjusted between the optical waveguide 2 connected via the liquid ball 812 and the optical fiber bundle 5. Thereafter, ultraviolet rays are irradiated toward each liquid ball 812. As a result, the liquid ball 812 is cured in a state where the gap distance d is regulated, and the hardened liquid ball 812 becomes the first portion 81.

Next, as shown in FIG. 15, a liquid resin material 821 constituting the second portion 82 is applied to each contact portion 11 by the spray 30 (spray method). Thereafter, the liquid resin material 821 is irradiated with ultraviolet rays. Thereby, as shown in FIG. 16, the liquid resin material 821 is cured, the cured resin material 821 becomes the second portion 82, and each contact portion is sealed with the sealing material 8G.
The optical waveguide assembly 1G can be manufactured by such a manufacturing method.

  The optical waveguide assembly of the present invention has been described above with respect to the illustrated embodiment. However, the present invention is not limited to this, and each part constituting the optical waveguide assembly may be any element that can exhibit the same function. It can be replaced with the configuration of Moreover, arbitrary components may be added.

  Moreover, the optical waveguide assembly of the present invention may be a combination of any two or more configurations (features) of the above embodiments.

  Further, in the optical waveguide of the optical waveguide joined body, there may be a core portion that is not used, that is, a core portion to which the optical fiber is not joined.

  In the optical fiber bundle of the optical waveguide joined body, there may be an optical fiber that is not used, that is, an optical fiber in which the core portion of the optical waveguide is not joined.

  The optical waveguide joined body may be one in which one core portion and one optical fiber are arranged.

  Moreover, the sealing material is not limited to being composed of a photocuring resin material, and may be composed of a thermosetting resin material, for example.

1, 1A, 1B, 1C, 1D, 1E, 1F, 1G Optical waveguide assembly 11 Contact portion 111 Gap 2, 2D, 2E Optical waveguide 30
3a Cladding layer (first cladding layer (cladding portion))
3b cladding layer (second cladding layer (cladding portion))
3c cladding layer (third cladding layer (cladding portion))
4 Core layer 4a Core layer (first core layer)
4b Core layer (second core layer)
41a, 41b, 41c, 41d, 41e, 41f, 41g, 41h Core part (waveguide channel)
411 End face 42a, 42b, 42c, 42d, 42e, 42f, 42g, 42h, 42i, 42j Side clad part (cladding part)
5, 5B, 5F Optical fiber bundles 6a, 6b, 6c, 6d, 6e, 6f, 6g, 6h, 6i, 6j, 6k, 6L, 6m, 6n, 6p Optical fiber 60 Core portion 61 End face 7 Holding member 8, 8G Sealing material 81 First part 811 Resin material 812 Liquid ball 82 Second part 821 Resin material 20 Water tank 30 Spray d Gap distance L Light

Claims (13)

An optical waveguide having at least one core portion;
At least one optical fiber;
The end face of the core part and the end face of the optical fiber face each other, and the periphery of the faced part is sealed with a sealing material, thereby joining the optical waveguide and the optical fiber, An optical waveguide assembly characterized in that light can be transmitted between the optical waveguide and the optical fiber. In the facing part, a gap is partially formed between the end face of the core part and the end face of the optical fiber,
The optical waveguide assembly according to claim 1, wherein a part of the sealing material enters the gap.   The optical waveguide joined body according to claim 2, wherein the sealing material has a refractive index of a portion entering the gap higher than a refractive index of the other portion.   The optical waveguide assembly according to claim 2 or 3, wherein a gap distance of the gap is 10 µm or less.   5. The optical waveguide joined body according to claim 1, wherein a refractive index of the sealing material is a value between a refractive index of the optical fiber and a refractive index of the core portion.   The optical waveguide assembly according to claim 1, wherein the sealing material is made of a resin material having photocurability or thermosetting.   The optical waveguide assembly according to any one of claims 1 to 6, wherein the optical fiber has a core portion made of a material different from a constituent material of the core portion of the optical waveguide.   The area of the end surface on the light incident side is larger than the area of the end surface on the output side when comparing the areas of the end surface of the core portion of the optical waveguide and the end surface of the core portion of the optical fiber. The optical waveguide joined body described.   The optical waveguide joined body according to claim 7 or 8, wherein one end surface includes the other end surface of the end surface of the core portion of the optical waveguide and the end surface of the core portion of the optical fiber. The optical waveguide is provided with a plurality of the core portions,
A plurality of the optical fibers are installed,
The optical waveguide joined body according to any one of claims 1 to 9, wherein one optical fiber is joined to each core portion. A plurality of the optical fibers are installed,
The optical waveguide joined body according to any one of claims 1 to 10, wherein a plurality of the optical fibers are joined to one core portion. A plurality of the core portions are installed in the optical waveguide,
The optical waveguide joined body according to claim 1, wherein a plurality of the core portions are joined to one optical fiber. A plurality of the optical fibers are installed,
The optical waveguide assembly according to any one of claims 1 to 12, further comprising a holding member that holds the plurality of optical fibers in a bundle.

Images