JP2014109655A - Ferrule, optical wiring component and electronic device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a ferrule that enables an optical waveguide to be securely fixed, and to provide an optical wiring component and an electronic device that have the ferrule provided and are excellent in reliability.SOLUTION: An optical wiring component 10 has an optical waveguide 1 and a ferrule 5. The ferrule 5 has a through-hole 50 that is formed by penetrating from one end through the other end, and has a tip part of the optical waveguide 1 inserted into the through-hole 50. A lower surface 101 of the optical waveguide 1 is fixed to a lower surface 5001 of the through-hole 50 via an adhesive layer 55. On the lower surface 5001 of the through-hole 50, a concave part 5001a is formed that opens to both of the lower surface 5001 and a tip end surface 58 of the ferrule 5. Since an adhesive for the adhesive layer 55 is capable of entering into the concave part 5001a, the adhesive layer results in being widely exposed in the tip surface 58 of the ferrule 5, and thus, a light irradiation area in the adhesive is secured.

Description

  The present invention relates to a ferrule, an optical wiring component, and an electronic device.

  An optical communication technique for transferring data using an optical carrier wave has been developed. In recent years, optical waveguides and optical fibers have been widely used as means for guiding the optical carrier wave from one point to another point. Among these, the optical waveguide has a linear core portion and a clad portion provided so as to cover the periphery thereof. The core part is made of a material that is substantially transparent to the light of the optical carrier wave, and the cladding part is made of a material having a refractive index lower than that of the core part.

  In the optical waveguide, light introduced from one end of the core portion is conveyed to the other end while being reflected at the boundary with the cladding portion. A light emitting element such as a semiconductor laser is disposed on the incident side of the optical waveguide, and a light receiving element such as a photodiode is disposed on the emission side. Light incident from the light emitting element propagates through the optical waveguide, is received by the light receiving element, and performs communication based on the flickering pattern of the received light or its intensity pattern.

  By the way, an optical waveguide generally performs short-distance optical communication, whereas an optical fiber is used for long-distance optical communication. Therefore, by connecting these, it becomes possible to connect the local network and the backbone network.

  For the connection between the optical waveguide and the optical fiber, for example, a configuration in which the end face of the optical waveguide and the end face of the optical fiber are held in contact with each other is employed (see, for example, Patent Document 1). For this holding, a coupling mechanism that can be fitted to each other is used. Specifically, the first ferrule that holds the end of the optical waveguide and the second ferrule that holds the end of the optical fiber are coupled by fitting the alignment pin and the fitting hole.

  Here, the optical waveguide described in Patent Document 1 has a band shape, and the lower surface is bonded onto the substrate. The first ferrule has an optical wiring receiving groove, and the first ferrule is fixed on the substrate in a state where the optical waveguide is received in the optical wiring receiving groove. Thus, the end portion of the optical waveguide is in a state where the upper surface and both side surfaces are covered with the first ferrule and the lower surface is covered with the substrate. In addition, an adhesive is filled in the gap between the optical waveguide and the optical wiring housing groove, and the optical waveguide and the first ferrule are fixed.

JP 2011-75688 A

  As the adhesive filled in the gap between the optical waveguide and the optical wiring receiving groove, a photo-curable adhesive is generally used. The photocurable adhesive undergoes a curing reaction upon irradiation with light, and develops adhesiveness accordingly. However, since the gap between the optical waveguide and the optical wiring housing groove is extremely thin, even if light is applied to the filled adhesive, the light does not reach every corner of the adhesive. For this reason, the adhesive is not sufficiently cured, and there is a problem that the optical waveguide and the first ferrule cannot be fixed securely.

  An object of the present invention is to provide a ferrule that can securely fix an optical waveguide, and a highly reliable optical wiring component and an electronic apparatus including the ferrule.

Such an object is achieved by the present inventions (1) to (8) below.
(1) A ferrule including a storage portion that is provided from a base end to a front end and can store a part of an optical waveguide,
The storage portion includes a recess provided in a part of a surface facing the optical waveguide when the optical waveguide is stored, and is open on both the surface and the front end surface of the ferrule. Ferrule.

  (2) The ferrule according to (1), wherein the storage portion is a through hole that is provided from a proximal end to a distal end and into which the optical waveguide can be inserted.

  (3) The ferrule according to (1), wherein the storage portion is a groove that is provided from a proximal end to a distal end and can store the optical waveguide.

  (4) In the above (1) to (3), the shape of the concave portion when viewed from above is an elongated shape having a long axis in a direction parallel to a direction connecting the base end and the tip end. The ferrule according to any one of the above.

  (5) The ferrule according to any one of (1) to (4), wherein the concave portion is also opened to a base end side of the ferrule.

(6) The storage unit is configured to store a part of a strip-shaped optical waveguide,
The ferrule according to any one of (1) to (5), wherein a surface of the storage portion facing the optical waveguide is configured to face a main surface of the strip-shaped optical waveguide.

(7) An optical wiring component comprising: the ferrule according to any one of (1) to (6) above; and an optical waveguide stored in the storage unit.
(8) An electronic apparatus comprising the optical wiring component according to (7).

According to the present invention, a ferrule capable of reliably fixing an optical waveguide is obtained.
Moreover, according to this invention, a reliable optical wiring component and electronic device provided with the said ferrule are obtained.

It is a perspective view which shows 1st Embodiment of the optical wiring component of this invention. It is the sectional view on the AA line of FIG. 1, and the sectional view on the BB line. It is a perspective view which shows 1st Embodiment of the ferrule of this invention. It is the sectional view on the AA line and BB line of FIG. It is the perspective view which expanded and illustrated only the optical waveguide which the optical wiring component of FIG. 1 contains. It is a figure which shows 2nd Embodiment of the ferrule of this invention, Comprising: Sectional drawing of 2nd Embodiment equivalent to AA sectional drawing of FIG. 2 and 2nd equivalent to BB sectional drawing of FIG. It is sectional drawing of embodiment. It is a modification of the ferrule shown in FIG. It is a figure which shows 3rd Embodiment of the ferrule of this invention, Comprising: Sectional drawing of 3rd Embodiment corresponded in AA sectional drawing of FIG. 2 and 3rd equivalent to BB sectional drawing of FIG. It is sectional drawing of embodiment. It is a modification of the ferrule shown in FIG.

  Hereinafter, the ferrule, optical wiring component, and electronic device of the present invention will be described in detail based on preferred embodiments shown in the accompanying drawings.

<Optical wiring parts>
<< First Embodiment >>
First, a first embodiment of the optical wiring component of the present invention and a first embodiment of the ferrule of the present invention included therein will be described.

  FIG. 1 is a perspective view showing a first embodiment of an optical wiring component of the present invention, FIG. 2 is a cross-sectional view taken along lines AA and BB in FIG. 1, and FIG. 4 is a cross-sectional view taken along line AA and BB in FIG. 3, and FIG. 5 is an enlarged view of only the optical waveguide included in the optical wiring component in FIG. FIG. In the following description, the upper side in FIGS. 2, 4 and 5 is referred to as “upper” and the lower side is referred to as “lower”.

  An optical wiring component 10 shown in FIG. 1 has an optical waveguide 1 and a ferrule 5 provided at an end of the optical waveguide 1.

  The optical waveguide 1 shown in FIG. 1 is in the form of a strip having a long cross-sectional shape with a thickness smaller than the width. In the optical waveguide 1, an optical signal can be transmitted between one end and the other end in the longitudinal direction. In each drawing of the present application, only the vicinity of one end of the optical waveguide 1 is illustrated, and the other portions are not illustrated, but the configuration near the other end may be the same as that near one end. it can. In the present specification, one end portion of the optical waveguide 1 in each drawing is also referred to as a “tip portion”, and an end face at one end is also referred to as a “tip surface”.

  As shown in FIG. 5, such an optical waveguide 1 includes a laminate in which a clad layer 11, a core layer 13, and a clad layer 12 are laminated in this order from below. Further, the core layer 13 shown in FIG. 5 is formed with two long core portions 14 provided in parallel and side clad portions 15 adjacent to the side surfaces of the core portions 14.

  A ferrule 5 is provided at the tip of the optical waveguide 1 shown in FIG. 1 so as to cover the tip. That is, the ferrule 5 has a through hole (storage portion) 50 in which the optical waveguide 1 can be stored, and the tip of the optical waveguide 1 is inserted into the through hole 50. The ferrule 5 is configured so that one end surface thereof is aligned with the front end surface of the optical waveguide 1. In this specification, one end of the ferrule 5 in each drawing is referred to as a “tip”, an end face of one end is referred to as a “tip face”, and the other end of the ferrule 5 serving as an insertion port of the optical waveguide 1 is referred to as a “base end”. The end surface at the other end is referred to as a “base end surface”. The through hole 50 is formed to penetrate from the base end to the tip end of the ferrule 5.

  In the optical wiring component 10, the lower surface 101 which is one main surface of the front end portion of the optical waveguide 1 is the surface facing the lower surface 101 of the optical waveguide 1 among the inner wall surfaces of the through holes 50 via the adhesive layer 55. It is fixed to a certain lower surface 5001. On the other hand, the upper surface 102 which is the other main surface of the distal end portion of the optical waveguide 1 is separated from the upper surface 5002 of the through hole 50, and both side surfaces 103 and 103 of the distal end portion of the optical waveguide 1 are also formed in the through hole. 50 side surfaces 5003 and 5003 are separated from each other.

  Here, even in the conventional optical wiring component, the optical waveguide and the ferrule are bonded through the adhesive layer as described above, and generally a photo-curable adhesive is used. However, since the gap between the optical waveguide and the ferrule is very thin, even after the optical waveguide is inserted into the through-hole of the ferrule and light is applied to the adhesive from the tip side of the ferrule, light is emitted to every corner of the adhesive. Has not arrived. For this reason, the adhesive is not sufficiently cured, and the optical waveguide and the ferrule cannot be reliably fixed.

  In view of this problem, the present inventor has intensively studied a ferrule structure capable of improving the curability of the photocurable adhesive without significantly complicating the ferrule structure. In addition, the above-described problem can be effectively solved by providing a recess that opens on both the surface and the front end surface of the ferrule in a part of the surface facing the optical waveguide in the housing portion that houses the optical waveguide of the ferrule. The present invention has been found and the present invention has been completed.

  That is, in the through hole 50 of the ferrule 5 shown in FIG. 1, the lower surface 5001 is formed with a recess 5001a in which the lower surface 5001 is recessed. As shown in FIGS. 3 and 4, the recess 5001 a is configured to open to the front end surface 58 of the ferrule 5 and the lower surface 5001 of the through hole 50. Moreover, the recessed part 5001a is extended | stretched to the base end side of the ferrule 5, and is comprised so that it may open | release also to the base end side.

  By forming such a recess 5001a on the lower surface 5001 of the through hole 50, a part of the uncured material of the adhesive layer 55 enters the recess 5001a as shown in FIG. As a result, the uncured material of the adhesive layer 55 is widely exposed on the front end surface of the ferrule 5 by the amount that has entered the recess 5001a. The exposed portion of the uncured product of the adhesive layer 55 can receive a large amount of light when the uncured product is irradiated with light and cured. In addition, a photocurable adhesive usually reacts with an initiator contained by exposure to generate radicals and cations, and a polymerization reaction, that is, a curing reaction proceeds. In addition, since the reaction of the initiator occurs in a chain, the curing reaction can be rapidly caused as the light irradiation area increases.

  On the other hand, since the recess 5001a is also open to the lower surface 5001 of the through-hole 50, the reaction of the initiator spreads quickly to the entire lower surface 5001. Thereby, the curing reaction proceeds on the entire lower surface 5001 with the exposed portion as the center, and the curing can be completed in a shorter time to every corner of the adhesive layer 55. As a result, a highly reliable optical wiring component 10 in which the optical waveguide 1 and the ferrule 5 are securely fixed can be obtained.

  Moreover, the hardening reaction of an adhesive agent can be further accelerated | stimulated because the recessed part 5001a is also opened also at the base end side. That is, when light is irradiated not only from the distal end side but also from the proximal end side of the concave portion 5001a, the light can enter from both the longitudinal directions of the concave portion 5001a, so that the curing reaction can be further promoted.

  Further, by providing the concave portion 5001a, a part of the adhesive layer 55 enters the concave portion 5001a, so that an anchor effect is generated between the adhesive layer 55 and the ferrule 5. As a result, the adhesive force between the optical waveguide 1 and the ferrule 5 can be further enhanced as compared with the case where the concave portion 5001a is not provided.

Hereinafter, each part of the optical wiring component 10 will be further described in detail.
(Optical waveguide)
The optical waveguide 1 is a long member having a band shape in plan view, and transmits an optical signal from one end to the other end.

  The two core portions 14 shown in FIG. 5 are surrounded by the clad portion (the side clad portion 15 and the clad layers 11 and 12), and light can be confined and propagated in the core portion 14.

  Although the refractive index of the core part 14 should just be larger than the refractive index of a clad part, it is preferable that the difference is 0.3% or more, and it is more preferable that it is 0.5% or more. On the other hand, the upper limit value is not particularly set, but is preferably about 5.5%. If the difference in refractive index is less than the lower limit value, the effect of propagating light may be reduced. On the other hand, if the difference in refractive index exceeds the upper limit value, further improvement in light transmission efficiency cannot be expected.

The refractive index difference is expressed by the following equation when the refractive index of the core portion 14 is A and the refractive index of the cladding portion is B.
Refractive index difference (%) = | A / B-1 | × 100

  Further, the refractive index distribution in the width direction in the cross section of the core portion 14 may be any shape distribution. This refractive index distribution may be a so-called step index (SI) type distribution in which the refractive index changes discontinuously, or a so-called graded index (GI) type distribution in which the refractive index changes continuously. May be. If the SI type distribution is used, it is easy to form a refractive index distribution. If the GI type distribution is used, the probability that the signal light is collected in a region having a high refractive index is increased, so that transmission efficiency is improved.

  Further, the core portion 14 may be linear or curved in plan view. Furthermore, the core part 14 may branch or cross | intersect on the way.

  The cross-sectional shape of the core portion 14 is not particularly limited, and may be a circle such as a perfect circle, an ellipse, or an oval, or a polygon such as a triangle, a quadrangle, a pentagon, or a hexagon. By being (rectangular), there is an advantage that the core portion 14 can be easily formed.

  The width and height of the core portion 14 (thickness of the core layer 13) are not particularly limited, but are preferably about 1 to 200 μm, more preferably about 5 to 100 μm, and more preferably 10 to 70 μm. More preferably, it is about. Thereby, it is possible to increase the density of the core portion 14 while suppressing a decrease in the transmission efficiency of the optical waveguide 1.

  On the other hand, as shown in FIG. 5, when a plurality of core portions 14 are arranged in parallel, the width of the side cladding portion 15 located between the core portions 14 is preferably about 5 to 250 μm, and preferably 10 to 200 μm. More preferably, it is about 10 to 120 μm. Thereby, it is possible to increase the density of the core portion 14 while preventing the optical signals from being mixed (crosstalk) between the core portions 14.

  The constituent material (main material) of the core layer 13 as described above is, for example, acrylic resin, methacrylic resin, polycarbonate, polystyrene, cyclic ether resin such as epoxy resin or oxetane resin, polyamide, polyimide, poly Benzoxazole, polysilane, polysilazane, silicone resin, fluorine resin, polyurethane, polyolefin resin, polybutadiene, polyisoprene, polychloroprene, polyester such as PET and PBT, polyethylene succinate, polysulfone, polyether, benzocyclo In addition to various resin materials such as cyclic olefin resins such as butene resin and norbornene resin, glass materials such as quartz glass and borosilicate glass can be used. Note that the resin material may be a composite material in which materials having different compositions are combined.

  The average thickness of the cladding layers 11 and 12 is preferably about 0.05 to 1.5 times the average thickness of the core layer 13, and more preferably about 0.1 to 1.25 times. Specifically, the average thickness of the cladding layers 11 and 12 is preferably about 1 to 200 μm, more preferably about 3 to 100 μm, and further preferably about 5 to 60 μm. Thereby, the function as a clad part is ensured while preventing the optical waveguide 1 from becoming thicker than necessary.

  Further, as the constituent material of the cladding layers 11 and 12, for example, the same material as the constituent material of the core layer 13 described above can be used, and in particular, (meth) acrylic resin, epoxy resin, silicone resin, It is preferably at least one selected from the group consisting of polyimide resins, fluorine resins, and polyolefin resins, and (meth) acrylic resins or epoxy resins are more preferable.

  The refractive index distribution in the thickness direction of the cross section of the optical waveguide 1 is not particularly limited, and examples thereof include SI type and GI type distributions.

  Although the width | variety of the optical waveguide 1 is not specifically limited, It is preferable that it is about 2-100 mm, and it is more preferable that it is about 5-50 mm.

  Moreover, the number of the core parts 14 formed in the optical waveguide 1 is not particularly limited, but is preferably about 1 to 100. When the number of core portions 14 is large, the optical waveguide 1 may be multilayered as necessary. Specifically, the optical waveguide 1 shown in FIG. 5 can be multilayered by alternately stacking core layers and cladding layers.

  The optical waveguide 1 shown in FIG. 5 includes a support film 2 as the lowermost layer and a cover film 3 as the uppermost layer.

  Examples of the constituent material of the support film 2 and the cover film 3 include various resin materials such as polyethylene terephthalate (PET), polyolefin such as polyethylene and polypropylene, polyimide, and polyamide.

  Moreover, although the average thickness of the support film 2 and the cover film 3 is not specifically limited, It is preferable that it is about 5-500 micrometers, and it is more preferable that it is about 10-400 micrometers. Thereby, since the support film 2 and the cover film 3 will have moderate rigidity, while supporting the core layer 13 reliably, the core layer 13 can be reliably protected from external force and an external environment.

  Note that the gap between the clad layer 11 and the support film 2 and the gap between the clad layer 12 and the cover film 3 are each via a member such as an adhesive, an adhesive, an adhesive sheet, and an adhesive sheet, or by thermocompression bonding. It is glued.

(Ferrule)
The ferrule 5 is provided at the tip of the optical waveguide 1 and can optically connect the optical waveguide 1 to other optical components. The ferrule 5 may include a part conforming to various connector standards. Examples of such connector standards include a miniature MT connector, an MT connector defined in JIS C 5981, a 16MT connector, and a two-dimensional array type. MT connector, MPO connector, MPX connector, etc. are mentioned.

  As shown in FIGS. 1 and 2, two guide holes 511 are opened on the distal end surface 58 of the ferrule 5 according to the present embodiment. The guide hole 511 is formed so as to penetrate from the proximal end surface of the ferrule 5 to the distal end surface 58. When connecting other optical components to the optical wiring component 10, guide pins provided on the other optical component side are inserted into these guide holes 511. Thereby, while aligning the ferrule 5 and another optical component, both can be fixed. That is, the guide hole 511 is used as a connection mechanism for connecting the optical waveguide 1 to other optical components.

  Note that the guide hole 511 may not be opened on the proximal end side as long as the guide hole 511 is opened on the distal end surface 58.

  Moreover, it may replace with the said connection mechanism and may be made to connect using the latching structure using the latching by a nail | claw, an adhesive agent, etc.

  In the lower surface 5001 of the through hole 50 shown in FIG. 1, three recesses 5001 a extend from the distal end surface 58 of the ferrule 5 to the proximal end side.

  The shape of each recess 5001a is an elongated shape having a major axis in the direction connecting the distal end and the proximal end of the ferrule 5, that is, in the direction parallel to the longitudinal direction of the optical waveguide 1, when the lower surface 5001 is viewed in plan. For this reason, when light is irradiated to the uncured material of the adhesive layer 55 that has entered the recess 5001a, the light can be efficiently delivered to the base end side of the ferrule 5 through the recess 5001a. That is, the concave portion 5001a serves as a light guide, and a portion that cannot be directly exposed can be indirectly exposed. Thereby, not only the chain of the curing reaction in the photocurable adhesive but also the progress of the light can be used to further accelerate the curing reaction.

  The number of the recesses 5001a formed on the lower surface 5001 is appropriately set according to, for example, the size of the optical waveguide 1 or the ferrule 5, the curability of the adhesive necessary for assembling the optical wiring component 10, the shape of the lower surface 5001, etc. Although not limited, Preferably it is about 1-30 pieces, More preferably, it is about 2-20 pieces. As a result, the adhesive can be reliably cured in a short time while securing a certain amount of a flat region of the lower surface 5001 and maintaining the positional accuracy of the optical waveguide 1 fixed to the lower surface 5001. Moreover, since it is a number of this level, since the shape of the ferrule 5 is not remarkably complicated, it is preferable also from the viewpoint of ease of manufacturing the ferrule 5.

  Although the area ratio which the recessed part 5001a occupies in the lower surface 5001 is not specifically limited, It is preferable that it is about 0.5 to 50%, and it is more preferable that it is about 1 to 40%. By setting the area ratio within the above range, by securing a certain amount of the flat region of the lower surface 5001, the positional accuracy of the optical waveguide 1 fixed to the lower surface 5001, and by securing a certain amount of the area of the recess 5001a. Adhesion reliability can be made highly compatible. That is, when the area ratio is below the lower limit, the ratio of the recesses 5001a is relatively small, and the adhesive may not be sufficiently cured. On the other hand, when the area ratio exceeds the upper limit value, the ratio of the recesses 5001a becomes relatively large, and the region for determining the position of the optical waveguide 1 becomes small. Therefore, the positional accuracy of the optical waveguide 1 after fixing decreases, that is, There is a risk that positional deviation from the design increases.

  In addition, the planar view shape of the recessed part 5001a is not limited to a linear shape as shown in FIG. 3, For example, it may branch on the way or may cross | intersect. Further, the width of the concave portion 5001a may gradually increase or decrease gradually from the distal end surface 58 toward the proximal end side.

  Further, the ferrule 5 is provided with, for example, a recess that is open on the lower surface 5001 but not open on the tip surface 58 other than the recess that is open on both the lower surface 5001 and the tip surface 58, such as the recess 5001a. May be. By providing such a recess, the above-described anchor effect can be further enhanced.

  On the other hand, the shape of the cross section perpendicular to the major axis of the recess 5001a is not limited to a substantially semicircular shape as shown in FIG. 3, for example, a polygon such as a triangle, a quadrangle, a pentagon, a trapezoid, a half star, A hook shape or the like may be used. In addition, the cross-sectional shape of the recess 5001a may change in the middle from the distal end surface 58 toward the proximal end side.

  In addition, when the front end surface 58 of the ferrule 5 is seen in a plan view, as shown in FIG. 4A, the surfaces may be discontinuously connected at the connecting portion between the recess 5001 a and the lower surface 5001. It is preferable that they are connected continuously (smoothly). Thereby, since a discontinuous surface cannot be formed on the lower surface of the adhesive layer 55, it is possible to avoid stress from being easily concentrated on the adhesive layer 55 due to the shape action.

  Further, the depth of the recess 5001a is not particularly limited, but the maximum depth in the normal direction from the lower surface 5001 is preferably about 2 to 500 μm, and more preferably about 5 to 400 μm. By setting the depth of the concave portion 5001a within the above range, it is possible to increase the exposure area of the adhesive and the anchor effect, and to suppress an increase in thermal expansion due to the volume of the adhesive layer 55 becoming too large. it can. That is, if the depth of the concave portion 5001a is less than the lower limit, depending on the size of the optical waveguide 1 or the ferrule 5, the adhesive may not be sufficiently cured, while the depth of the concave portion 5001a is When the upper limit is exceeded, depending on the size of the optical waveguide 1 and the ferrule 5, the volume of the adhesive layer 55 becomes too large and the amount of thermal expansion increases. For example, the adhesive interface with the optical waveguide 1 is peeled off or the optical waveguide 1 is moved. There is a risk of causing problems such as stress concentration.

  Moreover, although both side surfaces 103 and 103 among the front-end | tip parts of the optical waveguide 1 may be being fixed to or contact | abutted to the side surfaces 5003 and 5003 of the through-hole 50, as shown to Fig.2 (a). The side surfaces 5003 and 5003 may be separated from each other. As a result, for example, even when a volume change occurs in the optical waveguide 1 due to a temperature change or a humidity change, the change can be absorbed by the gap, and unnecessary stress concentration is generated in the optical waveguide 1. Can be relaxed. As a result, it is possible to suppress the transmission efficiency from being reduced due to the stress concentration or the occurrence of separation between the optical waveguide 1 and the ferrule 5.

  Further, the top surface 102 of the distal end portion of the optical waveguide 1 may be fixed to or in contact with the top surface 5002 of the through hole 50, but is separated from the top surface 5002 as shown in FIG. Also good. Thereby, the above-described stress concentration can be further alleviated.

  The separation distance L1 (see FIG. 2) between the side surface 103 of the optical waveguide 1 and the side surface 5003 of the through hole 50 is appropriately set according to the size of the optical waveguide 1 or the ferrule 5, and is not particularly limited. The thickness is about 1000 μm, more preferably about 10 to 750 μm, still more preferably about 15 to 500 μm, and particularly preferably about 25 to 350 μm. By setting the separation distance L1 within the above range, it is possible to sufficiently suppress the decrease in transmission efficiency and the occurrence of peeling of the adhesive interface even in an environment where the temperature change and humidity change are large, and the optical wiring component 10 is significantly increased in size. Can be avoided.

  Note that a region that is locally deviated from the range of the separation distance may be included between the side surface 103 of the optical waveguide 1 and the side surface 5003 of the through hole 50. In that case, the area ratio of this region is preferably 30% or less.

  On the other hand, by performing mold release treatment on the side surface 103 of the optical waveguide 1 or the side surface 5003 of the through hole 50, the lubricity (slidability) between the optical waveguide 1 and the through hole 50 can be improved. Thereby, even if the separation distance L1 is further reduced, the above-described effects can be obtained. Specifically, by performing mold release treatment on at least one of the side surface 103 of the optical waveguide 1 and the side surface 5003 of the through hole 50, the range of the separation distance L1 is preferably 0.001 to 1000 μm, more preferably 0. .1 to 500 μm, more preferably 1 to 200 μm. Thereby, while being able to relieve | stress concentration more reliably, the design freedom degree of the optical wiring component 10 can be raised.

  Examples of the release treatment include a treatment for applying or forming a release agent on the surface to be treated, a surface modification treatment such as a plasma treatment, and the like. Examples of the release agent include fluorine release agents, silicon release agents, polyethylene release agents, polypropylene release agents, paraffin release agents, montan release agents, carnauba release agents. An agent etc. are mentioned, The thing containing 1 type of these, or a 2 or more types of mixture is used.

  Further, the separation distance L2 (see FIG. 2) between the upper surface 102 of the optical waveguide 1 and the upper surface 5002 of the through-hole 50 is appropriately set according to the size of the optical waveguide 1 and the ferrule 5, and is not particularly limited. The thickness is about 10 to 2000 μm, more preferably about 15 to 1000 μm, still more preferably about 100 to 1000 μm, and particularly preferably about 300 to 800 μm. By setting the separation distance L2 within the above range, it is possible to sufficiently suppress a decrease in transmission efficiency and occurrence of peeling even in an environment where a temperature change and a humidity change are large, and to avoid a significant increase in the size of the optical wiring component 10. it can.

  It should be noted that a region that is locally deviated from the range of the separation distance may be included between the upper surface 102 of the optical waveguide 1 and the upper surface 5002 of the through hole 50. In that case, the area ratio of this region is preferably 30% or less.

  Further, it is preferable that the thickness of the adhesive layer 55 is approximately equal to the separation distance L2. As a result, the optical waveguide 1 can be accurately and reliably fixed to the ferrule 5.

  The separation distance L2 may be smaller, equal or larger than the separation distance L1, but is preferably about 30 to 300% of the separation distance L1, and is about 50 to 200%. More preferred. Thereby, the optical waveguide 1 can be more accurately and reliably fixed to the phenol 5.

  In addition, the lubricity (slidability) between the optical waveguide 1 and the through hole 50 is improved by performing the above-described mold release treatment on the upper surface 102 of the optical waveguide 1 or the upper surface 5002 of the through hole 50. Can do. Thereby, even if the separation distance L2 is further narrowed, the above-described effects can be obtained. Specifically, by performing mold release treatment on at least one of the upper surface 102 of the optical waveguide 1 and the upper surface 5002 of the through-hole 50, the range of the separation distance L2 is preferably 0.001 to 1000 μm, more preferably 0. .1 to 500 μm, more preferably 1 to 200 μm. Thereby, while being able to relieve | stress concentration more reliably, the design freedom degree of the optical wiring component 10 can be raised.

  Moreover, although the cross-sectional shape of the through-hole 50 of the ferrule 5 may be constant from the base end to the front end, it may change midway.

  The ferrule 5 according to the present embodiment is configured such that the height of the through hole 50 gradually increases toward the base end side of the ferrule 5 as shown in FIG. Specifically, a part of the bottom surface 5001 of the through hole 50 on the base end side is curved so that the downward inclination gradually increases toward the base end. That is, a part of the base end side of the lower surface 5001 is a curved surface 5001b, and the curvature gradually increases toward the base end. In addition, a part of the upper surface 5002 on the base end side is curved so that the upward inclination gradually increases toward the base end. That is, a part of the base end side of the upper surface 5002 is a curved surface 5002b, and the curvature gradually increases toward the base end.

  When the through-hole 50 has such a configuration, as shown in FIG. 2B, when the optical waveguide 1 is inserted into the through-hole 50, the distance between the optical waveguide 1 and the lower surface 5001; In addition, the distance between the optical waveguide 1 and the upper surface 5002 gradually increases toward the base end. Due to such a gap, the optical waveguide 1 can be curved along the lower surface 5001 and the upper surface 5002 when an external force pulling upward or downward in FIG. 2B is applied to the optical waveguide 1. . As a result, the optical waveguide 1 is gently curved along the curved surface 5001b and the curved surface 5002b, and abrupt bending is suppressed. As a result, it is possible to prevent the occurrence of problems such as a decrease in transmission efficiency and disconnection due to a sharp bend.

  Further, the optical waveguide 1 can move relatively freely according to the external force until the optical waveguide 1 receiving the external force comes into contact with the curved surfaces 5001b and 5002b. During this time, an external force can be passed, so that the optical waveguide 1 can be prevented from coming out of the through hole 50.

  The length L3 of the curved surface 5001b in the lower surface 5001 and the length L3 of the curved surface 5002b in the upper surface 5002 are preferably about 5 to 50% of the total length L4 of the ferrule 5, and are about 10 to 40%. More preferably. By setting the ratio of L3 to L4 within the above range, reliable fixation of the optical waveguide 1 to the ferrule 5 and durability against the external force of the optical wiring component 10 can be made highly compatible. That is, if L3 / L4 is less than the lower limit value, the tolerance for the external force of the optical wiring component 10 may be reduced. On the other hand, if L3 / L4 exceeds the upper limit value, the fixing force is reduced and strong force is reduced. There is a risk that the lock may be released when pulled with the.

  As a constituent material of the ferrule 5, for example, phenol resin, epoxy resin, olefin resin, urea resin, melamine resin, various resin materials such as unsaturated polyester resin, stainless steel, aluminum alloy, etc. Various metal materials etc. are mentioned.

(Adhesive layer)
Examples of the constituent material of the adhesive layer 55 include a cured product of an adhesive and a cured product of a bonding sheet.

  Among these, as adhesives, for example, epoxy adhesives, acrylic adhesives, urethane adhesives, silicone adhesives, olefin adhesives, various hot melt adhesives (polyesters, modified olefins), etc. Can be mentioned.

  On the other hand, as a constituent material of the bonding sheet, for example, bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol AD type epoxy resin, bisphenol type epoxy resin such as bisphenol S type epoxy resin, phenol novolac type epoxy resin, cresol In addition to novolak epoxy resins such as novolac epoxy resins, aromatic epoxy resins such as trisphenolmethane triglycidyl ether, various epoxy resins such as naphthalene epoxy resins and dicyclopentadiene epoxy resins, polyimide, polyamideimide Such imide resins, silicone resins, phenol resins, urea resins and the like can be used, and one or more of these can be used in combination.

  In addition to the above thermosetting resin, the constituent material of the bonding sheet is acrylonitrile-butadiene rubber (NBR), reactive terminal carboxyl group NBR (CTBN), styrene-butadiene rubber (SBR), polybutadiene, acrylic rubber, etc. These rubber components may include thermoplastic resins such as vinyl acetate resin, polyvinyl alcohol resin, polyvinyl acetal resin, acrylic resin, polyacrylonitrile resin, vinyl urethane resin, polyester resin, and polyamide resin. The content of these rubber components and the thermoplastic resin is preferably about 10 to 200 parts by mass, more preferably about 20 to 150 parts by mass with respect to 100 parts by mass of the thermosetting resin.

  Although the tensile elastic modulus (Young's modulus) of the adhesive layer 55 is slightly different depending on the size of the optical waveguide 1, etc., it is preferably about 100 to 20000 MPa, more preferably about 300 to 15000 MPa, and even more preferably 500 to The pressure is about 12500 MPa, and particularly preferably about 1000 to 10,000 MPa. By setting the tensile elastic modulus of the adhesive layer 55 within the above range, the optical waveguide 1 can be more securely fixed to the ferrule 5 and the stress concentration in the optical waveguide 1 can be more reliably relaxed to reduce transmission loss. The increase can be suppressed.

  In addition, the tensile elasticity modulus of the contact bonding layer 55 is measured based on the method prescribed | regulated to JISK7127, and measurement temperature shall be 25 degreeC.

  Moreover, it is preferable that the glass transition temperature of the contact bonding layer 55 is about 30-180 degreeC, and it is more preferable that it is about 35-140 degreeC. By setting the glass transition temperature of the adhesive layer 55 within the above range, the heat resistance of the optical wiring component 10 can be further increased.

  The glass transition temperature of the adhesive layer 55 can be measured by a dynamic viscoelasticity measurement method (DMA method).

  In the present embodiment, the side surfaces 103 and 103 of the optical waveguide 1 and the side surfaces 5003 and 5003 of the through hole 50 are separated from each other, but the adhesive layer 55 is also formed of the through hole 50 as shown in FIG. It is preferable that the side surfaces 5003 and 5003 are separated from each other. Thereby, it can suppress more reliably that local stress concentration generate | occur | produces in the optical waveguide 1. FIG. The separation distance in this case is set similarly to the separation distance L1.

<< Second Embodiment >>
Next, a second embodiment of the optical wiring component of the present invention and a second embodiment of the ferrule of the present invention will be described.

  6 is a view showing a second embodiment of the ferrule of the present invention, which is a cross-sectional view of the second embodiment corresponding to a cross-sectional view taken along line AA of FIG. 2 and a cross-sectional view taken along line BB of FIG. A corresponding sectional view of the second embodiment, FIG. 7, is a modified example of the ferrule shown in FIG.

Hereinafter, although 2nd Embodiment is described, it demonstrates centering around difference with 1st Embodiment, The description is abbreviate | omitted about the same matter. 6 and 7, the same components as those in the first embodiment are denoted by the same reference numerals as those described above, and detailed description thereof is omitted.
The second embodiment is the same as the first embodiment except that the configuration of the recess 5001a is different.

  In the ferrule 5 shown in FIG. 6, the concave portion 5001 a is not opened to the proximal end side, and is formed to stop halfway through the through hole 50.

  Also in such a ferrule 5, since the recessed part 5001a is open | released to both the lower surface 5001 of the through-hole 50, and the front end surface 58 of the ferrule 5, the optical wiring component 10 provided with this ferrule 5 and this ferrule 5 is The same operations and effects as the first embodiment are achieved.

  Moreover, in the ferrule 5 which concerns on this embodiment, the hardening reaction of an adhesive agent can be advanced sequentially from a front end side to a base end side. For this reason, as compared with the case where the curing reaction starts all at once in the entire adhesive, distortion is less likely to occur at the adhesive interface between the optical waveguide 1 and the adhesive layer 55. As a result, unintended deformation of the optical waveguide 1 can be suppressed.

  Moreover, the rectangular shape as shown to Fig.7 (a) may be sufficient as the cross-sectional shape of the recessed part 5001a.

  In the ferrule 5 shown in FIG. 7, only one recess 5001a having a rectangular cross-sectional shape is formed. The concave portion 5001a is formed by recessing substantially the center of the width of the lower surface 5001 of the through hole 50 downward, and is open to both the lower surface 5001 and the front end surface 58 as described above. Further, the recess 5001 a is not opened to the base end side, and is formed partway through the through hole 50.

  The width of the concave portion 5001a (the width of the opening of the front end surface 58) W (the total of the widths in the case of a plurality of widths) W is appropriately set according to the rigidity of the optical waveguide 1 or the like. It is preferably about -80%, more preferably about 10-60%. Thereby, particularly good curability can be obtained.

«Third embodiment»
Next, a third embodiment of the optical wiring component of the present invention and a third embodiment of the ferrule of the present invention will be described.

  FIG. 8 is a view showing a third embodiment of the ferrule of the present invention, and is a cross-sectional view of the third embodiment corresponding to the cross-sectional view taken along line AA of FIG. 2 and a cross-sectional view taken along line BB of FIG. A corresponding sectional view of the third embodiment, FIG. 9, is a modification of the ferrule shown in FIG.

Hereinafter, the third embodiment will be described, but the description will focus on the differences from the first and second embodiments, and description of similar matters will be omitted. In FIG. 8, the same components as those in the first embodiment are denoted by the same reference numerals as those described above, and detailed description thereof is omitted.
The third embodiment is the same as the first embodiment except that the configuration of the ferrule 5 is different.

  A ferrule 5 shown in FIG. 8 includes a groove (storage portion) 501 that is formed from the tip to the base end instead of the through hole 50 and can store the optical waveguide 1, and the optical waveguide 1 is accommodated in the groove 501. The tip is stored. The front end surface 58 of the ferrule 5 is configured to be aligned with the front end surface of the optical waveguide 1. The distal end portion of the optical waveguide 1 is fixed to the bottom surface 5011 of the groove 501 via an adhesive layer.

  A recess 5011a similar to the recess 5001a according to the first embodiment is formed on the bottom surface 5011 of the groove 501. This concave portion 5011a is also open to both the front end surface 58 of the ferrule 5 and the bottom surface 5011 of the groove 501 similarly to the concave portion 5001a. For this reason, this ferrule 5 and the optical wiring component 10 provided with this ferrule 5 show the effect | action and effect similar to 1st Embodiment.

  Further, since the optical waveguide 1 is fixed by being accommodated in the groove 501, the fixing work, that is, the assembling work of the optical wiring component 10 is facilitated as compared with the case where the optical waveguide 1 is accommodated and fixed in the through hole 50. .

  Note that the groove 501 may be filled with a sealing material as necessary. At this time, it is preferable that the sealing material does not enter the gaps between the side surfaces 103 and 103 at the front end of the optical waveguide 1 and the side surfaces 5012 and 5012 of the groove 501. For example, in the case of a curable encapsulant, it can be prevented from entering a small gap by optimizing the fluidity of the encapsulant before curing, so that it may be used. Alternatively, a procedure may be taken in which a spacer is inserted so as to fill this gap, the sealing material is filled in the groove 501 in this state, and the spacer is removed after the sealing material is cured.

  Alternatively, the through-hole 50 may be substantially formed by closing the open portion of the groove 501 and the optical waveguide 1 may be accommodated therein.

  The ferrule 5 shown in FIG. 9 includes a main body 51 having a groove 501 formed from the front end to the base end, and a lid 52 provided so as to close the open portion of the groove 501 while being fitted in the groove 501. It is configured. FIG. 9 illustrates a state before the lid body 52 is accommodated in the groove 501, that is, a disassembled state of the ferrule 5. In addition, in the groove 501 illustrated in FIG. 9, two surfaces standing upward from the bottom surface 5011 are referred to as side surfaces 5012. When the lid body 52 is accommodated in the groove 501, the through hole 50 is substantially formed. That is, the lower surface of the through-hole 50 is constituted by the bottom surface 5011 of the groove 501, both side surfaces are constituted by the side surfaces 5012 of the groove 501, and the upper surface is constituted by the lower surface 521 of the lid body 52. The tip portion of the optical waveguide 1 is inserted into the through hole 50, and the both are fixed to form the optical wiring component 10. Note that closing the opening of the groove 501 with the lid 52 means placing the lid 52 so as to close the opening, thereby making the groove 501 a substantial “hole”. At this time, the side surface of the lid 52 may be in contact with the side surface 5012 of the groove 501 or may be fixed.

  On the other hand, the lower surface 521 of the lid 52 may be fixed to the upper surface 102 of the optical waveguide 1. At this time, the side surface of the lid body 52 is preferably separated from the side surface 5012 of the groove 501. Thereby, the lid body 52 is not directly fixed to the main body 51 but indirectly fixed via the optical waveguide 1. As a result, the lid 52 can move in the same manner as the optical waveguide 1 while fulfilling the function of protecting the optical waveguide 1. In other words, it can move independently of the main body 51. As a result, the ferrule 5 can reliably protect the optical waveguide 1 without causing stress concentration on the optical waveguide 1.

  Note that the separation distance between the side surface of the lid body 52 and the side surface 5012 of the groove 501 can be set similarly to the separation distance L1 described above. Further, by setting the distance between the side surface of the lid body 52 and the side surface 5012 of the groove 501 in this way, it is possible to expose the adhesive through this gap. Therefore, the curing reaction of the adhesive can be further accelerated.

<Electronic equipment>
As described above, the optical wiring component of the present invention as described above can suppress a decrease in transmission efficiency in the optical waveguide even when connected to other optical components. Therefore, by providing the optical wiring component of the present invention, a highly reliable electronic device (electronic device of the present invention) capable of performing high-quality optical communication is obtained.

  Examples of the electronic device including the optical wiring component of the present invention include electronic devices such as a mobile phone, a game machine, a router device, a WDM device, a personal computer, a television, and a home server. In any of these electronic devices, it is necessary to transmit a large amount of data at high speed between an arithmetic device such as an LSI and a storage device such as a RAM. Therefore, by providing such an electronic device with the optical wiring component of the present invention, problems such as noise and signal degradation peculiar to electric wiring can be eliminated, and a dramatic improvement in performance can be expected.

  In addition, the amount of heat generated in the optical waveguide portion is greatly reduced compared to electrical wiring. For this reason, the electric power required for cooling can be reduced and the power consumption of the whole electronic device can be reduced.

  As mentioned above, although the ferrule of this invention, the optical wiring component, and the electronic device were demonstrated based on embodiment of illustration, this invention is not limited to these.

  For example, the ferrule according to each of the above-described embodiments may be attached to one end of the optical waveguide, while a different ferrule or connector may be attached to the other end, and the light receiving / emitting element is mounted in the optical path conversion unit. It may be. Further, no ferrule or the like may be attached to the other end.

  Further, depending on the shape of the optical waveguide, the surface on which the recess is formed may be a surface other than the lower surface of the through hole, for example, a side surface or an upper surface. You may make it form. When the optical waveguide has a main surface and a side surface, if a recess is formed on the inner wall surface of the through-hole facing the main surface of the optical waveguide, reliable fixing and acceleration of the curing reaction can be achieved. In particular, both can be achieved.

DESCRIPTION OF SYMBOLS 1 Optical waveguide 101 Lower surface 102 Upper surface 103 Side surface 10 Optical wiring component 11, 12 Clad layer 13 Core layer 14 Core part 15 Side surface cladding part 2 Support film 3 Cover film 5 Ferrule 50 Through-hole 5001 Lower surface 5001a Concave part 5001b Curved surface 5002 Upper surface 5002b Curved Surface 5003 Side surface 501 Groove 5011 Bottom surface 5011a Recessed portion 5012 Side surface 51 Main body 511 Guide hole 52 Cover body 521 Bottom surface 55 Adhesive layer 58 Tip surface

Claims (8)

A ferrule provided with a storage portion that is provided from the base end to the front end and can store a part of the optical waveguide,
The storage portion includes a recess provided in a part of a surface facing the optical waveguide when the optical waveguide is stored, and is open on both the surface and the front end surface of the ferrule. Ferrule.   The ferrule according to claim 1, wherein the storage portion is a through hole that is provided from a proximal end to a distal end and into which the optical waveguide can be inserted.   The ferrule according to claim 1, wherein the storage portion is a groove that is provided from a proximal end to a distal end and can store the optical waveguide.   The said recessed part has comprised the elongate shape which has a long axis in the direction parallel to the direction which connects a base end and a front-end | tip when the said surface is planarly viewed. Ferrule.   The ferrule according to any one of claims 1 to 4, wherein the concave portion is further opened to a base end side of the ferrule. The storage unit is configured to store a part of a strip-shaped optical waveguide,
The ferrule according to any one of claims 1 to 5, wherein a surface of the housing portion facing the optical waveguide is configured to face a main surface of the strip-shaped optical waveguide.   An optical wiring component comprising: the ferrule according to any one of claims 1 to 6; and an optical waveguide housed in the housing portion.   An electronic apparatus comprising the optical wiring component according to claim 7.

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